Perry McCarty

All Publications

• Pilot-scale temperate-climate treatment of domestic wastewater with a staged anaerobic fluidized membrane bioreactor (SAF-MBR) BIORESOURCE TECHNOLOGY Shin, C., McCarty, P. L., Kim, J., Bae, J. 2014; 159: 95-103

  Abstract

  A pilot-scale staged anaerobic fluidized membrane bioreactor (SAF-MBR) was operated continuously for 485 days, without chemical cleaning of membranes, treating primary-settled domestic wastewater with wastewater temperature between 8 and 30°C and total hydraulic retention time (HRT) between 4.6 and 6.8h. Average chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) removals averaged 81% and 85%, respectively, during the first winter at 8-15°C before full acclimation had occurred. However, subsequently when fully acclimated, summer and winter COD removals of 94% and 90% and BOD5 removals of 98% and 90%, respectively, were obtained with average effluent COD never higher than 23 mg/L nor BOD5 higher than 9 mg/L. Operational energy requirement of 0.23 kW h/m(3) could be met with primary and secondary methane production, and could be reduced further through hydraulic change. Biosolids production in all seasons averaged 0.051 g volatile suspended solids per g COD removed.

  View details for DOI 10.1016/j.biortech.2014.02.060

  View details for Web of Science ID 000335393500014

• Effect of temperature on the treatment of domestic wastewater with a staged anaerobic fluidized membrane bioreactor WATER SCIENCE AND TECHNOLOGY Yoo, R. H., Kim, J. H., McCarty, P. L., Bae, J. H. 2014; 69 (6): 1145-1150

  Abstract

  A laboratory staged anaerobic fluidized membrane bioreactor (SAF-MBR) system was applied to the treatment of primary clarifier effluent from a domestic wastewater treatment plant with temperature decreasing from 25 to 10 °C. At all temperatures and with a total hydraulic retention time of 2.3 h, overall chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) removals were 89% and 94% or higher, with permeate COD and BOD5 of 30 and 7 mg/L or lower, respectively. No noticeable negative effects of low temperature on organic removal were found, although a slight increase to 3 mg/L in volatile fatty acids concentrations in the effluent was observed. Biosolids production was 0.01-0.03 kg volatile suspended solids/kg COD, which is far less than that with aerobic processes. Although the rate of trans-membrane pressure at the membrane flux of 9 L/m(2)/h increased as temperature decreased, the SAF-MBR was operated for longer than 200 d before chemical cleaning was needed. Electrical energy potential from combustion of the total methane production (gaseous and dissolved) was more than that required for system operation.

  View details for DOI 10.2166/wst.2013.793

  View details for Web of Science ID 000334505800003

• Efficient single-stage autotrophic nitrogen removal with dilute wastewater through oxygen supply control BIORESOURCE TECHNOLOGY Kwak, W., McCarty, P. L., Bae, J., Huang, Y., Lee, P. 2012; 123: 400-405

  Abstract

  Autotrophic nitrogen removal via ammonia oxidizing (AOB) and anaerobic ammonium oxidizing (anammox) bacteria was evaluated for treatment of a dilute 50mg/L ammonia-containing solution in a single-stage nitrogen-removal filter at 25°C. Important was an external oxygenation system that permitted close control and measurement of oxygen supply, a difficulty with the generally used diffused air systems. Hydraulic retention time (HRT) was reduced in steps from 15 to 1h. At 1h HRT, total nitrogen (TN) removals varied between 73% and 94%, the maximum being obtained with a benchmark oxygenation ratio of 0.75mol O(2)/mol ammonia fed. At higher ratios, nitrate was formed causing TN removal efficiency to decrease. With lower ratios, TN and ammonia removals decreased in proportion to the decrease in BOR. When operating at or below the BOR, nitrate formation equaled no more than 2% of the ammonia removed, a value much less than has previously been reported.

  View details for DOI 10.1016/j.biortech.2012.07.076

  View details for Web of Science ID 000310401100059

  View details for PubMedID 22940348

• Lower operational limits to volatile fatty acid degradation with dilute wastewaters in an anaerobic fluidized bed reactor BIORESOURCE TECHNOLOGY Shin, C., Bae, J., McCarty, P. L. 2012; 109: 13-20

  Abstract

  A general concern that anaerobic treatment of dilute wastewaters is limited by the inability of methanogenic and related syntrophic organisms to reduce substrate concentrations adequately was evaluated using a 35 °C granular activated carbon-containing laboratory-scale fluidized bed reactor fed an acetate-propionate equal chemical oxygen demand (COD) mixture synthetic wastewater. Contrary to general expectations, effluent acetate and propionate concentrations remained near or below their detection limits of 0.4 mg COD/L with influent COD of 200mg/L, 17 min hydraulic retention time, and organic loading as high as 17 kg COD/m(3)d, or with influent COD values ranging from 45 to 2010 mg COD/L and organic loadings of 4.2-4.5 kg COD/m(3)d. The effluent acetate concentrations in these well-fed systems were at or much below reported threshold limits for starving non-fed cultures, suggesting that a better understanding of threshold values and factors affecting treatment efficiency with anaerobic treatment of dilute wastewaters is needed.

  View details for DOI 10.1016/j.biortech.2012.01.014

  View details for Web of Science ID 000301810500003

  View details for PubMedID 22285295

• Domestic Wastewater Treatment as a Net Energy Producer-Can This be Achieved? ENVIRONMENTAL SCIENCE & TECHNOLOGY McCarty, P. L., Bae, J., Kim, J. 2011; 45 (17): 7100-7106

  Abstract

  In seeking greater sustainability in water resources management, wastewater is now being considered more as a resource than as a waste-a resource for water, for plant nutrients, and for energy. Energy, the primary focus of this article, can be obtained from wastewater's organic as well as from its thermal content. Also, using wastewater's nitrogen and P nutrients for plant fertilization, rather than wasting them, helps offset the high energy cost of producing synthetic fertilizers. Microbial fuel cells offer potential for direct biological conversion of wastewater's organic materials into electricity, although significant improvements are needed for this process to be competitive with anaerobic biological conversion of wastewater organics into biogas, a renewable fuel used in electricity generation. Newer membrane processes coupled with complete anaerobic treatment of wastewater offer the potential for wastewater treatment to become a net generator of energy, rather than the large energy consumer that it is today.

  View details for DOI 10.1021/es2014264

  View details for Web of Science ID 000294373400002

  View details for PubMedID 21749111

• Anaerobic Fluidized Bed Membrane Bioreactor for Wastewater Treatment ENVIRONMENTAL SCIENCE & TECHNOLOGY Kim, J., Kim, K., Ye, H., Lee, E., Shin, C., McCarty, P. L., Bae, J. 2011; 45 (2): 576-581

  Abstract

  Anaerobic membrane bioreactors have potential for energy-efficient treatment of domestic and other wastewaters, membrane fouling being a major hurdle to application. It was found that fouling can be controlled if membranes are placed directly in contact with the granular activated carbon (GAC) in an anaerobic fluidized bed bioreactor (AFMBR) used here for post-treatment of effluent from another anaerobic reactor treating dilute wastewater. A 120-d continuous-feed evaluation was conducted using this two-stage anaerobic treatment system operated at 35 °C and fed a synthetic wastewater with chemical oxygen demand (COD) averaging 513 mg/L. The first-stage was a similar fluidized-bed bioreactor without membranes (AFBR), operated at 2.0-2.8 h hydraulic retention time (HRT), and was followed by the above AFMBR, operating at 2.2 h HRT. Successful membrane cleaning was practiced twice. After the second cleaning and membrane flux set at 10 L/m(2)/h, transmembrane pressure increased linearly from 0.075 to only 0.1 bar during the final 40 d of operation. COD removals were 88% and 87% in the respective reactors and 99% overall, with permeate COD of 7 ± 4 mg/L. Total energy required for fluidization for both reactors combined was 0.058 kWh/m(3), which could be satisfied by using only 30% of the gaseous methane energy produced. That of the AFMBR alone was 0.028 kWh/m(3), which is significantly less than reported for other submerged membrane bioreactors with gas sparging for fouling control.

  View details for DOI 10.1021/es1027103

  View details for Web of Science ID 000286090500038

  View details for PubMedID 21158433

• Comparative evaluation of chloroethene dechlorination to ethene by Dehalococcoides-like microorganisms ENVIRONMENTAL SCIENCE & TECHNOLOGY Cupples, A. M., Spormann, A. M., McCarty, P. L. 2004; 38 (18): 4768-4774

  Abstract

  Reductive dehalogenation of tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (DCE), and vinyl chloride (VC) was examined in four cultures containing Dehalococcoides-like microorganisms. Dechlorination and growth kinetics were compared using a Monod growth-rate model for multiple electron acceptor usage with competition. Included were the Victoria mixed culture containing Dehalococcoides species strain VS (from Victoria, TX), the mixed culture KB-1/VC (from southern Ontario), the Pinellas mixed culture (from Pinellas, FL), and D. ethenogenes strain 195. All cultures, with the exception of D. ethenogenes strain 195, grew with VC as catabolic electron acceptor. A dilution method was developed that allows a valid comparison to be made of dehalogenating kinetics between different mixed cultures. Using this procedure, maximum growth rates on VC were found to be similar for strain VS and KB-1/VC (0.42-0.49 +/- 0.02 d(-1)) but slower for the Pinellas culture (0.28 +/- 0.01 d(-1)). The 16S rRNA gene sequences were determined to ensure that no cross contamination between cultures had occurred. Following enrichment of the VC dechlorinating microorganisms on VC, the cultures were amended with DCE, TCE, or PCE. The three mixed cultures failed to dechlorinate PCE or did so very slowly. However, the dilution technique indicated that all experienced growth on TCE and DCE as well as on VC. Maximum growth rates on DCE alone were quite similar (0.43-0.46 d(-1)), while the Pinellas culture grew faster on TCE alone (0.49 d(-1)) than did the other two mixed cultures (0.33-0.35 d(-1)). Half-velocity and inhibition constants for growth on TCE were also determined for the three mixed cultures; both constants were found to be essentially equal and the same for the different cultures, varying between only 8.6 and 10.5 microM. The ability of the strain VS, KB-1/VC, and Pinellas cultures to utilize TCE rapidly with conversion to ethene is quite different from that of any other reported microorganism. It was separately confirmed with more traditional cell-counting techniques that strain VS coupled TCE, as well as DCE and VC, utilization with growth. This is the first report of an organism obtaining energy for growth through every step in the reduction of TCE to ethene. Also, as suggested by the dilution technique, the dehalogenating organisms in the KB-1/VC and Pinellas cultures appear to obtain growth from TCE utilization as well. Such ability to grow while dehalogenating TCE to ethene will be an important advantage for their use in bioaugmentation.

  View details for DOI 10.1021/es049965z

  View details for Web of Science ID 000223938500016

  View details for PubMedID 15487786

• Anaerobic fluidized membrane bioreactor polishing of baffled reactor effluent during treatment of dilute wastewater JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY Lee, R., McCarty, P. L., Bae, J., Kim, J. 2015; 90 (3): 391-397

  View details for DOI 10.1002/jctb.4596

  View details for Web of Science ID 000349465800005

• Superior Removal of Disinfection Byproduct Precursors and Pharmaceuticals from Wastewater in a Staged Anaerobic Fluidized Membrane Bioreactor Compared to Activated Sludge ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS McCurry, D. L., Bear, S. E., Bae, J., Sedlak, D. L., McCarty, P. L., Mitch, W. A. 2014; 1 (11): 459-464

  View details for DOI 10.1021/ez500279a

  View details for Web of Science ID 000350831700005

• The effect of fluidized media characteristics on membrane fouling and energy consumption in anaerobic fluidized membrane bioreactors SEPARATION AND PURIFICATION TECHNOLOGY Aslam, M., McCarty, P. L., Bae, J., Kim, J. 2014; 132: 10-15

  View details for DOI 10.1016/j.seppur.2014.04.049

  View details for Web of Science ID 000340300600002

• Anaerobic treatment of low-strength wastewater: A comparison between single and staged anaerobic fluidized bed membrane bioreactors BIORESOURCE TECHNOLOGY Bae, J., Shin, C., Lee, E., Kim, J., McCarty, P. L. 2014; 165: 75-80

  Abstract

  Performance of a single anaerobic fluidized membrane bioreactor (AFMBR) was compared with that of a staged anaerobic fluidized membrane bioreactor system (SAF-MBR) that consisted of an anaerobic fluidized bed bioreactor (AFBR) followed by an AFMBR. Both systems were fed with an equal COD mixture (200mg/L) of acetate and propionate at 25°C. COD removals of 93-96% were obtained by both systems, independent of the hydraulic retention times (HRT) of 2-4h. Over more than 200d of continuous operation, trans-membrane pressure (TMP) in both systems was less than 0.2bar without significant membrane fouling as a result of the scouring of membrane surfaces by the moving granular activated carbon particles. Results of bulk liquid suspended solids, extracellular polymeric substances (EPS), and soluble microbial products (SMP) analyses also revealed no significant differences between the two systems, indicating the single AFMBR is an effective alternative to the SAF-MBR system.

  View details for DOI 10.1016/j.biortech.2014.02.065

  View details for Web of Science ID 000338710700013

  View details for PubMedID 24630367

• The effect of SRT on nitrate formation during autotrophic nitrogen removal of anaerobically treated wastewater WATER SCIENCE AND TECHNOLOGY Lee, P., Kwak, W., Bae, J., McCarty, P. L. 2013; 68 (8): 1751-1756

  Abstract

  Autotrophic nitrogen removal, coupling nitritation (ammonium to nitrite) with anaerobic ammonium oxidation (anammox), offers a promising nitrogen-removal alternative, especially for post-treatment of anaerobically-treated wastewater. However, previous reports suggest that less than 90% total nitrogen removal should be expected with this process alone because over 10% of the ammonium removed will be converted to nitrate. This is caused because nitrite conversion to nitrate is required for reduction of carbon dioxide to cell carbon. However, recent research results suggest that more limited nitrate formation of only a few per cent sometimes occurs. It was hypothesized such lower nitrate yields may result from use of long solids retention times (SRT) where net biological yields are low, and providing that the ratio of oxygen added to influent ammonium concentrations is maintained at or below 0.75 mol/mol. Overall reaction equations were developed for each process and combined to evaluate the potential effect of SRT on process stoichiometry. The results support the use of a long SRT to reduce net cell yield, which in turn results in a small percentage conversion to nitrate during ammonium removal and high total nitrogen removals in the range of 90 to 94%.

  View details for DOI 10.2166/wst.2013.368

  View details for Web of Science ID 000327140500010

  View details for PubMedID 24185056

• Two-stage anaerobic fluidized-bed membrane bioreactor treatment of settled domestic wastewater WATER SCIENCE AND TECHNOLOGY Bae, J., Yoo, R., Lee, E., McCarty, P. L. 2013; 68 (2): 394-399

  Abstract

  A two-stage anaerobic fluidized-bed membrane bioreactor (SAF-MBR) system was applied for the treatment of primary-settled domestic wastewater that was further pre-treated by either 10 μm filtration or 1 mm screening. While the different pre-treatment options resulted in different influent qualities, the effluent qualities were quite similar. In both cases at a total hydraulic retention time of 2.3 h and 25 °C, chemical oxygen demand and biochemical oxygen demand (BOD5) removals were 84-91% and 92-94%, with effluent concentrations lower than 25 and 7 mg/L, respectively. With a membrane flux of 6-12 L/m(2)/h, trans-membrane pressure remained below 0.2 bar during 310 d of continuous operation without need for membrane chemical cleaning or backwashing. Biosolids production was estimated to be 0.028-0.049 g volatile suspended solids/g BOD5, which is far less than that with comparable aerobic processes. Electrical energy production from combined heat and power utilization of the total methane produced (gaseous and dissolved) was estimated to be more than sufficient for total system operation.

  View details for DOI 10.2166/wst.2013.191

  View details for Web of Science ID 000322886600018

  View details for PubMedID 23863433

• Anaerobic treatment of municipal wastewater with a staged anaerobic fluidized membrane bioreactor (SAF-MBR) system BIORESOURCE TECHNOLOGY Yoo, R., Kim, J., McCarty, P. L., Bae, J. 2012; 120: 133-139

  Abstract

  A laboratory-scale staged anaerobic fluidized membrane bioreactor (SAF-MBR) system was used to treat a municipal wastewater primary-clarifier effluent. It was operated continuously for 192 days at 6-11 L/m(2)/h flux and trans-membrane pressure generally of 0.1 bar or less with no fouling control except the scouring effect of the fluidized granular activated carbon on membrane surfaces. With a total hydraulic retention time of 2.3h at 25°C, the average effluent chemical oxygen demand and biochemical oxygen demand concentrations of 25 and 7 mg/L yielded corresponding removals of 84% and 92%, respectively. Also, near complete removal of suspended solids was obtained. Biosolids production, representing 5% of the COD removed, equaled 0.049 g VSS/g BOD(5) removed, far less than the case with comparable aerobic processes. The electrical energy required for the operation of the SAF-MBR system, 0.047 kW h/m(3), could be more than satisfied by using the methane produced.

  View details for DOI 10.1016/j.biortech.2012.06.028

  View details for Web of Science ID 000308056000020

  View details for PubMedID 22784964

• Effects of influent DO/COD ratio on the performance of an anaerobic fluidized bed reactor fed low-strength synthetic wastewater BIORESOURCE TECHNOLOGY Shin, C., Lee, E., McCarty, P. L., Bae, J. 2011; 102 (21): 9860-9865

  Abstract

  The effect of influent DO/COD (dissolved oxygen/chemical oxygen demand) ratio on the performance of an anaerobic fluidized bed reactor (AFBR) containing GAC was studied. A high influent DO concentration was found to have adverse impacts on organic removal efficiency, methane production, and effluent suspended solids (SS) concentration. These problems resulted with a DO/COD ratio of 0.12, but not at a lower ratio of 0.05. At first organic removal appeared satisfactory at the higher DO/COD ratio at a hydraulic retention time of 0.30 h, but soon a rapid growth of oxygen-consuming zoogloeal-like organisms resulted, eventually causing high effluent SS concentrations. The influent DO also had an inhibitory effect, resulting in a long recovery time for adequate methanogenic activity to return after influent DO removal began. With the growing interest in anaerobic treatment of low COD wastewaters, the increased possibility of similar adverse DO effects occurring needs consideration.

  View details for DOI 10.1016/j.biortech.2011.07.109

  View details for Web of Science ID 000296124200005

  View details for PubMedID 21906938

• Model to Couple Anaerobic Process Kinetics with Biological Growth Equilibrium Thermodynamics ENVIRONMENTAL SCIENCE & TECHNOLOGY McCarty, P. L., Bae, J. 2011; 45 (16): 6838-6844

  Abstract

  Monod kinetics indicates a substrate concentration limit (S(min)) at biological growth equilibrium where growth is just balanced by decay. A relationship between S(min) and the Gibbs free energy available at growth equilibrium (?G(E)) was introduced into the Monod model and applied directly to chemostat cultures. Results from four anaerobic mixed-culture chemostat studies yielded ?G(E) of -17.7 ± 2.2 kJ/mol acetate converted to methane. ?G(E) for propionate syntrophs in propionate-fed cultures was -8.0 ± 3.1 kJ/mol propionate, compared with that of -3.0 ± 0.9 kJ/mol H(2) for the hydrogenotrophs present. With ethanol present, however, ?G(E) for the hydrogenotrophs became more favorable, -6.1 ± 1.6 kJ/mol H(2), while ?G(E) for propionate became positive even though propionate was consumed, suggesting an alternative interspecies electron transport route. The results suggest that S(min), normally considered a function of an organism's intrinsic rate characteristics, is also a function of solution characteristics, and this is likely the case for the substrate affinity coefficient, K, as well. A comparison between ?G(E) and S(min) and reported threshold thermodynamic and concentration limits, leads to the conclusion that ?G(E) and S(min) represent lower and upper bounds, respectively, on such values. This study indicates that knowledge gained from pure-culture studies applies well to more complex natural anaerobic systems.

  View details for DOI 10.1021/es2009055

  View details for Web of Science ID 000293758400017

  View details for PubMedID 21740015

• Bioaugmentation with butane-utilizing microorganisms to promote in situ cometabolic treatment of 1,1,1-trichloroethane and 1,1-dichloroethene JOURNAL OF CONTAMINANT HYDROLOGY Semprini, L., Dolan, M. E., Hopkins, G. D., McCarty, P. L. 2009; 103 (3-4): 157-167

  Abstract

  A field study was performed to evaluate the potential for in-situ aerobic cometabolism of 1,1,1-trichloroethane (1,1,1-TCA) through bioaugmentation with a butane enrichment culture containing predominantly two Rhodococcus sp. strains named 179BP and 183BP that could cometabolize 1,1,1-TCA and 1,1-dicholoroethene (1,1-DCE). Batch tests indicated that 1,1-DCE was more rapidly transformed than 1,1,1-TCA by both strains with 183BP being the most effective organism. This second in a series of bioaugmentation field studies was conducted in the saturated zone at the Moffett Field In Situ Test Facility in California. In the previous test, bioaugmentation with an enrichment culture containing the 183BP strain achieved short term in situ treatment of 1,1-DCE, 1,1,1-TCA, and 1,1-dichloroethane (1,1-DCA). However, transformation activity towards 1,1,1-TCA was lost over the course of the study. The goal of this second study was to determine if more effective and long-term treatment of 1,1,1-TCA could be achieved through bioaugmentation with a highly enriched culture containing 179BP and 183BP strains. Upon bioaugmentation and continuous addition of butane and dissolved oxygen and or hydrogen peroxide as sources of dissolved oxygen, about 70% removal of 1,1,1-TCA was initially achieved. 1,1-DCE that was present as a trace contaminant was also effectively removed (approximately 80%). No removal of 1,1,1-TCA resulted in a control test leg that was not bioaugmented, although butane and oxygen consumption by the indigenous populations was similar to that in the bioaugmented test leg. However, with prolonged treatment, removal of 1,1,1-TCA in the bioaugmented leg decreased to about 50 to 60%. Hydrogen pexoxide (H2O2) injection increased dissolved oxygen concentration, thus permitting more butane addition into the test zone, but more effective 1,1,1-TCA treatment did not result. The results showed bioaugmentation with the enrichment cultures was effective in enhancing the cometabolic treatment of 1,1,1-TCA and low concentrations of 1,1-DCE over the entire period of the 50-day test. Compared to the first season of testing, cometabolic treatment of 1,1,1-TCA was not lost. The better performance achieved in the second season of testing may be attributed to less 1,1-DCE transformation product toxicity, more effective addition of butane, and bioaugmentation with the highly enriched dual culture.

  View details for DOI 10.1016/j.jconhyd.2008.10.005

  View details for Web of Science ID 000263009100008

  View details for PubMedID 19022526

• Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater McCarty, P. L., Chu, M., Kitanidis, P. K. ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER. 2007: 276-282

  View details for DOI 10.1016/j.ejsobi.2007.03.004

  View details for Web of Science ID 000251684000003

• Bioaugmentation of butane-utilizing microorganisms for the in situ cometabolic treatment of 1,1-dichloroethene, 1,1-dichloroethane, and 1,1,1-trichloroethane EUROPEAN JOURNAL OF SOIL BIOLOGY Semprini, L., Dolan, M. E., Mathias, M. A., Hopkins, G. D., McCarty, P. L. 2007; 43 (5-6): 322-327

  View details for DOI 10.1016/j.ejsobi.2007.03.006

  View details for Web of Science ID 000251684000008

• Comparison between acetate and hydrogen as electron donors and implications for the reductive dehalogenation of PCE and TCE JOURNAL OF CONTAMINANT HYDROLOGY Lee, I., Bae, J., McCarty, P. L. 2007; 94 (1-2): 76-85

  Abstract

  Bioremediation by reductive dehalogenation of groundwater contaminated with tetrachloroethene (PCE) or trichloroethene (TCE) is generally carried out through the addition of a fermentable electron donor such as lactate, benzoate, carbohydrates or vegetable oil. These fermentable donors are converted by fermenting organisms into acetate and hydrogen, either of which might be used by dehalogenating microorganisms. Comparisons were made between H2 and acetate on the rate and extent of reductive dehalogenation of PCE. PCE dehalogenation with H2 alone was complete to ethene, but with acetate alone it generally proceeded only about half as fast and only to cis-1,2-dichloroethene (cDCE). Additionally, acetate was not used as an electron donor in the presence of H2. These findings suggest the fermentable electron donor requirement for PCE dehalogenation to ethene can be reduced up to 50% by separating PCE dehalogenation into two stages, the first of which uses acetate for the conversion of PCE to cDCE, and the second uses H2 for the conversion of cDCE to ethene. This can be implemented with a recycle system in which the fermentable substrate is added down-gradient, where the hydrogen being produced by fermentation effects cDCE conversion into ethene. The acetate produced is recycled up-gradient to achieve PCE conversion into cDCE. With the lower electron donor usage required, potential problems of aquifer clogging, excess methane production, and high groundwater chemical oxygen demand (COD) can be greatly reduced.

  View details for DOI 10.1016/j.jconhyd.2007.05.003

  View details for Web of Science ID 000250767600005

  View details for PubMedID 17610987

• Dependence of lumped mass transfer coefficient on scale and reactions kinetics for biologically enhanced NAPL dissolution ADVANCES IN WATER RESOURCES Chu, M., Kitanidis, P. K., McCarty, P. L. 2007; 30 (6-7): 1618-1629

  View details for DOI 10.1016/j.advwatres.2006.06.016

  View details for Web of Science ID 000246902300017

• Thermodynamic electron equivalents model for bacterial yield prediction: Modifications and comparative evaluations BIOTECHNOLOGY AND BIOENGINEERING McCarty, P. L. 2007; 97 (2): 377-388

  Abstract

  Modifications are made to an earlier thermodynamic model (TEEM1) for prediction of maximum microbial yields from aerobic and anaerobic as well as heterotrophic and autotrophic growth. The revised model (TEEM2) corrects for lower yields found with aerobic oxidations of organic compounds where an oxygenase is involved and with growth on single-carbon (C1) compounds. TEEM1 and TEEM2 are based on energy release and consumption as determined from the reduction potential or Gibbs free energy of (1/2)-reaction reduction equations together with losses of energy during energy transfer. Energy transfer efficiency is a key parameter needed to make predictions with TEEM2, and was determined through evaluations with extensive data sets on aerobic heterotrophic yield available in the literature. For compounds following normal catabolic pathways, the best-fit value for energy transfer efficiency was 0.37, which permitted accurate predictions of growth with a precision of 15%-20% as determined by standard deviation. Using the same energy transfer efficiency, a similar precision, but somewhat less accuracy was found for organic compounds where oxidation involves an oxygenase (estimates 8% too high) and for C1 compounds (estimates 17% too high). In spite of the somewhat lower accuracy, the TEEM2 modifications resulted in improved predictions over TEEM1 and the comparison models.

  View details for DOI 10.1002/bit.21250

  View details for Web of Science ID 000246434700017

  View details for PubMedID 17089390

• Laboratory, field, and modeling studies of bioaugmentation of butane-utilizing microorganisms for the in situ cometabolic treatment of 1,1-dichloroethene, 1,1-dichloroethane, and 1,1,1-trichloroethane ADVANCES IN WATER RESOURCES Semprini, L., Dolan, M. E., Mathias, M. A., Hopkins, G. D., McCarty, P. L. 2007; 30 (6-7): 1528-1546

  View details for DOI 10.1016/j.advwatres.2006.05.017

  View details for Web of Science ID 000246902300010

• Field evaluation of in situ source reduction of trichloroethylene in groundwater using bioenhanced in-well vapor stripping ENVIRONMENTAL SCIENCE & TECHNOLOGY Goltz, M. N., Gandhi, R. K., Gorelick, S. M., Hopkins, G. D., Smith, L. H., Timmins, B. H., McCarty, P. L. 2005; 39 (22): 8963-8970

  Abstract

  Two technologies in combination, cometabolic bioremediation and in-well vapor stripping, were applied to reduce trichloroethylene (TCE) concentrations in groundwater at a contaminant source area without the need to pump contaminated groundwater to the surface for treatment. The vapor-stripping well reduced source TCE concentrations (as high as 6-9 mg/L) by over 95%. Effluent from the well then flowed to two bioremediation wells, where additional reductions of approximately 60% were achieved. TCE removal was extensively monitored (for research and not regulatory purposes) using an automated system that collected samples about every 45 min at 55 locations over an area of approximately 50 x 60 m2. During 4.5 months of system operation, total TCE mass removal was 8.1 kg, 7.1 kg of which resulted from in-well vapor stripping and 1.0 kg from biotreatment. The system reduced the average TCE concentration of about 3000 microg/L in the source-zone groundwater to about 250 microg/L in water leaving the treatment zone, effecting greater than 92% TCE removal. A 6 month rebound study after system operation ceased found TCE concentrations then increased significantly in the treatment zone due to diffusion from the fractured rock below and perhaps other processes, with mass increases of about 1.5 kg in the lower aquifer and 0.3 kg in the upper aquifer.

  View details for DOI 10.1021/es050628f

  View details for Web of Science ID 000233297100061

  View details for PubMedID 16323801

• Medical bioremediation: Prospects for the application of microbial catabolic diversity to aging and several major age-related diseases AGEING RESEARCH REVIEWS de Grey, A. D., Alvarez, P. J., BRADY, R. O., Cuervo, A. M., Jerome, W. G., McCarty, P. L., Nixon, R. A., Rittmann, B. E., Sparrow, J. R. 2005; 4 (3): 315-338

  Abstract

  Several major diseases of old age, including atherosclerosis, macular degeneration and neurodegenerative diseases are associated with the intracellular accumulation of substances that impair cellular function and viability. Moreover, the accumulation of lipofuscin, a substance that may have similarly deleterious effects, is one of the most universal markers of aging in postmitotic cells. Reversing this accumulation may thus be valuable, but has proven challenging, doubtless because substances resistant to cellular catabolism are inherently hard to degrade. We suggest a radically new approach: augmenting humans' natural catabolic machinery with microbial enzymes. Many recalcitrant organic molecules are naturally degraded in the soil. Since the soil in certain environments - graveyards, for example - is enriched in human remains but does not accumulate these substances, it presumably harbours microbes that degrade them. The enzymes responsible could be identified and engineered to metabolise these substances in vivo. Here, we survey a range of such substances, their putative roles in age-related diseases and the possible benefits of their removal. We discuss how microbes capable of degrading them can be isolated, characterised and their relevant enzymes engineered for this purpose and ways to avoid potential side-effects.

  View details for DOI 10.1016/j.arr.2005.03.008

  View details for Web of Science ID 000232100700001

  View details for PubMedID 16040282

• Modeling microbial reactions at the plume fringe subject to transverse mixing in porous media: When can the rates of microbial reaction be assumed to be instantaneous? WATER RESOURCES RESEARCH Chu, M., Kitanidis, P. K., McCarty, P. L. 2005; 41 (6)

  View details for DOI 10.1029/2004WR003495

  View details for Web of Science ID 000229832500001

• Numerical model for biological fluidized-bed reactor treatment of perchlorate-contaminated groundwater ENVIRONMENTAL SCIENCE & TECHNOLOGY McCarty, P. L., Meyer, T. E. 2005; 39 (3): 850-858

  Abstract

  Biological fluidized-bed reactor (BFBR) treatment with 1.3 mm granular activated carbon as support medium is being used for removal of 2.6 mg/L perchlorate from contaminated groundwater in California. The California drinking-water action level of 4 microg/L for perchlorate requires 99.9% perchlorate removal. Sufficient ethanol, the electron donor, is added to remove oxygen and nitrate as well as perchlorate, as all three serve as electron acceptors, but with biological preference for oxygen and nitrate. A numerical BFBR model based upon basic physical, chemical, and biological processes including reaction stoichiometry, biofilm kinetics, and sequential electron acceptor usage was developed and evaluated with the full-scale treatment results. A key fitting parameter was bacterial detachment rate, which impacts reaction stoichiometry. For best model fit this was found to vary between 0.062 and 0.31 d(-1), with an average of 0.22 d(-1). The model indicates that GAC particle size, reactor diameter, and perchlorate concentration affect BFBR performance. While empty-bed detention time might be decreased somewhat below 10 min by an increase in either GAC particle size or reactor diameter, the current design provides a good factor of safety in operation. With a 10 min detention time, the effluent goal of 4 microg/L should be achievable even with influent perchlorate concentration as high as 10 mg/L.

  View details for DOI 10.1021/es040303j

  View details for Web of Science ID 000226712600034

  View details for PubMedID 15757349

• Simulated and experimental evaluation of factors affecting the rate and extent of reductive dehalogenation of chloroethenes with glucose JOURNAL OF CONTAMINANT HYDROLOGY Lee, I. S., Bae, J. H., Yang, Y. R., McCarty, P. L. 2004; 74 (1-4): 313-331

  Abstract

  Carbohydrates such as molasses are being added to aquifers to serve as electron donors for reductive dehalogenation of chloroethenes. Glucose, as a model carbohydrate, was studied to better understand the processes involved and to evaluate the effectiveness for dehalogenation of different approaches for carbohydrate addition. A simulation model was developed and calibrated with experimental data for the reductive dehalogenation of tetrachloroethene to ethene via cis-1,2-dichloroethene. The model included fermentors that convert the primary donor (glucose) into butyrate, acetate and hydrogen, methanogens, and two separate dehalogenator groups. The dehalogenation groups use the hydrogen intermediate as an electron donor and the different haloethenes as electron acceptors through competitive inhibition. Model simulations suggest first that the initial relative population size of dehalogenators and H(2)-utilizing methanogens greatly affects the degree of dehalogenation achieved. Second, the growth and decay of biomass from soluble carbohydrate plays a significant role in reductive dehalogenation. Finally, the carbohydrate delivery strategies used (periodic versus batch addition and the time interval between periodic addition) greatly affect the degree of dehalogenation that can be obtained with a given amount of added carbohydrate.

  View details for DOI 10.1016/j.jconhyd.2004.03.006

  View details for Web of Science ID 000224186500016

  View details for PubMedID 15358499

• Molecular identification of the catabolic vinyl chloride reductase from Dehalococcoides sp strain VS and its environmental distribution APPLIED AND ENVIRONMENTAL MICROBIOLOGY Muller, J. A., Rosner, B. M., von Abendroth, G., Meshulam-Simon, G., McCarty, P. L., Spormann, A. M. 2004; 70 (8): 4880-4888

  Abstract

  Reductive dehalogenation of vinyl chloride (VC) to ethene is the key step in complete anaerobic degradation of chlorinated ethenes. VC-reductive dehalogenase was partially purified from a highly enriched culture of the VC-respiring Dehalococcoides sp. strain VS. The enzyme reduced VC and all dichloroethene (DCE) isomers, but not tetrachloroethene (PCE) or trichloroethene (TCE), at high rates. By using reversed genetics, the corresponding gene (vcrA) was isolated and characterized. Based on the predicted amino acid sequence, VC reductase is a novel member of the family of corrinoid/iron-sulfur cluster containing reductive dehalogenases. The vcrA gene was found to be cotranscribed with vcrB, encoding a small hydrophobic protein presumably acting as membrane anchor for VC reductase, and vcrC, encoding a protein with similarity to transcriptional regulators of the NosR/NirI family. The vcrAB genes were subsequently found to be present and expressed in other cultures containing VC-respiring Dehalococcoides organisms and could be detected in water samples from a field site contaminated with chlorinated ethenes. Therefore, the vcrA gene identified here may be a useful molecular target for evaluating, predicting, and monitoring in situ reductive VC dehalogenation.

  View details for DOI 10.1128/AEM.70.8.4880-4888.2004

  View details for Web of Science ID 000223290100061

  View details for PubMedID 15294827

• Possible factors controlling the effectiveness of bioenhanced dissolution of non-aqueous phase tetrachloroethene ADVANCES IN WATER RESOURCES Chu, M., Kitanidis, P. K., McCarty, P. L. 2004; 27 (6): 601-615

  View details for DOI 10.1016/j.advwatres.2004.03.002

  View details for Web of Science ID 000221814200003

• Vinyl chloride and cis-dichloroethene dechlorination kinetics and microorganism growth under substrate limiting conditions ENVIRONMENTAL SCIENCE & TECHNOLOGY Cupples, A. M., Spormann, A. M., McCarty, P. L. 2004; 38 (4): 1102-1107

  Abstract

  The reductive dechlorination of tetrachloroethene (PCE) and trichloroethene (TCE) at contaminated sites often results in the accumulation of cis-1,2-dichloroethene (DCE) and vinyl chloride (VC), rather than the nonhazardous end product ethene. This accumulation may be caused by the absence of appropriate microorganisms, insufficient supply of donor substrate, or reaction kinetic limitations. Here, we address the issue of reaction kinetic limitations by investigating the effect of limiting substrate concentrations (electron donor and acceptor) on DCE and VC dechlorination kinetics and microorganism growth by bacterium VS. For this, a model based on Monod kinetics, but also accounting for competition between electron acceptors and the effect of low electron donor and acceptor concentrations (dual-substrate kinetics), was examined. Competitive coefficients for VC (7.8 +/- 1.5 microM) and DCE (3.6 +/- 1.1 microM) were obtained and included in the model. The half velocity coefficient for hydrogen, the electron donor, was experimentally determined (7 +/- 2 nM) through investigating dechlorination over different substrate concentrations. This complete model was then used, along with experimental data, to determine substrate concentrations at which the dechlorinating microorganisms would be in net decay. Notably, the model indicates net decay will result if the total electron acceptor concentration (DCE plus VC) is below 0.7 microM, regardless of electron donor levels. The ability to achieve sustainable bioremediation to acceptable levels can be greatly influenced by this threshold level.

  View details for DOI 10.1021/es0348647

  View details for Web of Science ID 000188996600025

  View details for PubMedID 14998024

• Effects of biomass accumulation on microbially enhanced dissolution of a PCE pool: a numerical simulation JOURNAL OF CONTAMINANT HYDROLOGY Chu, M., Kitanidis, P. K., McCarty, P. L. 2003; 65 (1-2): 79-100

  Abstract

  Recent studies have shown that dechlorinating bacteria can accelerate the dissolution rate of dense, nonaqueous phase liquids (DNAPLs) containing tetrachloroethene (PCE). We present an advection-dispersion-reaction model for a two-dimensional domain, with groundwater flowing over a pool of free-product PCE. PCE is converted to cis-1,2-dichloroethene (cDCE) and toxicity due to PCE or cDCE is neglected. We adopt previously published correlations relating biomass concentrations and hydraulic conductivity, accounting for biofilm growth and plug-like growth. The system of coupled equations is solved numerically. The high biotransformation rate of PCE increases the concentration gradient of PCE at the water-DNAPL interface, enhancing dissolution. The higher the electron donor (ED) concentration, the larger the dissolution enhancement. Based on the values of maximum specific rate we used, when the electron donor is unlimited, the active biomass accumulates adjacent to the water-NAPL interface and microbial reactions can significantly enhance the pool dissolution. The resulting steady-state dissolution rate can be approximated by a half-order solution when zero-order kinetics are suitable for representing the microbial reaction. However, bioclogging may significantly reduce local hydraulic conductivity; thus, it decreases the flow near the water-DNAPL interface, decreasing dissolution. When the ED is the limiting factor, active biomass accumulates away from the interface. This creates a no-flow zone between the active biomass and the interface. The enlargement of the no-flow zone, due to the donor limitation, diminishes the concentration gradient and the flushing around the water-DNAPL interface. Such adverse impacts may significantly decrease the enhancement predicted by models that do not consider the effects of bioclogging.

  View details for DOI 10.1016/S0169-7722(02)00232-2

  View details for Web of Science ID 000184322200005

  View details for PubMedID 12855202

• Growth of a Dehalococcoides-like microorganism on vinyl chloride and cis-dichloroethene as electron acceptors as determined by competitive PCR APPLIED AND ENVIRONMENTAL MICROBIOLOGY Cupples, A. M., Spormann, A. M., McCarty, P. L. 2003; 69 (2): 953-959

  Abstract

  A competitive PCR (cPCR) assay targeting 16S ribosomal DNA was developed to enumerate growth of a Dehalococcoides-like microorganism, bacterium VS, from a mixed culture catalyzing the reductive dehalogenation of cis-1,2-dichloroethene (cDCE) and vinyl chloride (VC), with hydrogen being used as an electron donor. The growth of bacterium VS was found to be coupled to the dehalogenation of VC and cDCE, suggesting unique metabolic capabilities. The average growth yield was (5.2 +/- 1.5) x 10(8) copies of the 16S rRNA gene/ micromol of Cl(-) (number of samples, 10), with VC being used as the electron acceptor and hydrogen as the electron donor. The maximum VC utilization rate (q) was determined to be 7.8 x 10(-10) micromol of Cl(-) (copy(-1) day(-1)), indicating a maximum growth rate of 0.4 day(-1). These average growth yield and q values agree well with values found previously for dechlorinating cultures. Decay coefficients were determined with growth (0.05 day(-1)) and no-growth (0.09 day(-1)) conditions. An important limitation of this cPCR assay was its inability to discriminate between active and inactive cells. This is an essential consideration for kinetic studies.

  View details for DOI 10.1128/AEM.69.2.953-959.2003

  View details for Web of Science ID 000180927100030

  View details for PubMedID 12571017

• Comparison between donor substrates for biologically enhanced tetrachloroethene DNAPL dissolution ENVIRONMENTAL SCIENCE & TECHNOLOGY Yang, Y. R., Mccarty, P. L. 2002; 36 (15): 3400-3404

  Abstract

  Tetrachloroethene (PCE) dense nonaqueous-phase liquid (DNAPL) can act as a persistent groundwater contamination source for decades. Biologically enhanced dissolution of pure PCE DNAPL has potential for reducing DNAPL longevity as indicated previously (Environ. Sci. Technol. 2000, 34, 2979). Reported here are expanded studies to evaluate donor substrates that offer different remediation strategies for bioenhanced DNAPL dissolution, including pentanol (soluble substrate, fed continuously), calcium oleate (insoluble substrate, placed in column initially by alternate pumping of sodium oleate and calcium chloride), and olive oil (mixed with PCE and placed in column initially). Compared with a no-substrate column control, the DNAPL dissolution rate was enhanced about three times when directly coupled with biological transformation. The major degradation product formed was cDCE, but significant amounts of VC and ethene were also found with some columns. Extensive methanogenesis, which reduced PCE transformation, occurred in both the pentanol-fed and oleate-amended columns, but not in the olive-oil-amended column, suggesting that methanogens managed to colonize column niches where PCE DNAPL was not present. Detrimental methane production in the pentanol-fed column was nearly eliminated by presaturating the feed solution with PCE. These results suggest potential DNAPL remediation strategies to enhance dehalogenation while controlling competitive methanogenic utilization of donor substrates.

  View details for DOI 10.1021/es011408e

  View details for Web of Science ID 000177242600049

  View details for PubMedID 12188371

• Full-scale demonstration of in situ cometabolic biodegradation of trichloroethylene in groundwater - 2. Comprehensive analysis of field data using reactive transport modeling WATER RESOURCES RESEARCH Gandhi, R. K., Hopkins, G. D., Goltz, M. N., Gorelick, S. M., McCarty, P. L. 2002; 38 (4)

  View details for DOI 10.1029/2001WR000380

  View details for Web of Science ID 000178932200003

• Strategies for in situ bioremediation of chlorinated solvent contaminated groundwater GROUNDWATER QUALITY: NATURAL AND ENHANCED RESTORATION OF GROUNDWATER POLLUTION Mccarty, P. L. 2002: 319-324

  View details for Web of Science ID 000185215100048

• Natural attenuation INNOVATIVE APPROACHES TO THE ON-SITE ASSESSMENT AND REMEDIATION OF CONTAMINATED SITES McCarty, P. L., Ellis, D. E. 2002; 15: 141-181

  View details for Web of Science ID 000180120800005

• Pore-scale modeling of biological clogging due to aggregate expansion: A material mechanics approach WATER RESOURCES RESEARCH Dupin, H. J., Kitanidis, P. K., McCarty, P. L. 2001; 37 (12): 2965-2979

  View details for Web of Science ID 000173283000010

• Simulations of two-dimensional modeling of biomass aggregate growth in network models WATER RESOURCES RESEARCH Dupin, H. J., Kitanidis, P. K., McCarty, P. L. 2001; 37 (12): 2981-2994

  View details for Web of Science ID 000173283000011

• The development of anaerobic treatment and its future WATER SCIENCE AND TECHNOLOGY McCarty, P. L. 2001; 44 (8): 149-156

  Abstract

  Anaerobic treatment is well over 100 years old. Its initial development was for the treatment of domestic wastewaters, using anaerobic filters and hybrid processes that are still of interest today. It then progressed in application to separate sludge digestion, then to treatment of dilute industrial wastewaters. Several processes have been developed that accomplish efficient treatment of wastewaters at short detention times. Major contributions to the broad application of anaerobic treatment and the better understanding of this process has come from efforts by G. Lettinga and his colleagues. They have emphasized its importance for meeting the need for sustainable development in the future. Greater efforts are now needed for broad application of anaerobic treatment for ridding the environment of unwanted organic materials by converting them into methane, a renewable energy source.

  View details for Web of Science ID 000172510100020

  View details for PubMedID 11730130

• Biologically enhanced dissolution of tetrachloroethene DNAPL ENVIRONMENTAL SCIENCE & TECHNOLOGY Yang, Y. R., McCarty, P. L. 2000; 34 (14): 2979-2984

  View details for Web of Science ID 000088156100016

• Impact of colony morphologies and disinfection on biological clogging in porous media ENVIRONMENTAL SCIENCE & TECHNOLOGY Dupin, H. J., McCarty, P. L. 2000; 34 (8): 1513-1520

  View details for Web of Science ID 000086456100022

• Novel biological removal of hazardous chemicals at trace levels WATER SCIENCE AND TECHNOLOGY McCarty, P. L. 2000; 42 (12): 49-60

  View details for Web of Science ID 000166382900006

• Effects of shear detachment on biomass growth and in situ bioremediation GROUND WATER MacDonald, T. R., Kitanidis, P. K., McCarty, P. L., Roberts, P. V. 1999; 37 (4): 555-563

  View details for Web of Science ID 000081268800016

• Mass-transfer limitations for macroscale bioremediation modeling and implications on aquifer clogging GROUND WATER MacDonald, T. R., Kitanidis, P. K., McCarty, P. L., Roberts, P. V. 1999; 37 (4): 523-531

  View details for Web of Science ID 000081268800012

• Mesoscale and microscale observations of biological growth in a silicon pore imaging element ENVIRONMENTAL SCIENCE & TECHNOLOGY Dupin, H. J., McCarty, P. L. 1999; 33 (8): 1230-1236

  View details for Web of Science ID 000079974600014

• Chlorinated ethene half-velocity coefficients (K-s) for reductive dehalogenation ENVIRONMENTAL SCIENCE & TECHNOLOGY Haston, Z. C., McCarty, P. L. 1999; 33 (2): 223-226

  View details for Web of Science ID 000078213600003

• Competition for hydrogen within a chlorinated solvent dehalogenating anaerobic mixed culture ENVIRONMENTAL SCIENCE & TECHNOLOGY Yang, Y. R., McCarty, P. L. 1998; 32 (22): 3591-3597

  View details for Web of Science ID 000076986800022

• Spreadsheet method for evaluation of biochemical reaction rate coefficients and their uncertainties by weighted nonlinear least-squares analysis of the integrated monod equation APPLIED AND ENVIRONMENTAL MICROBIOLOGY Smith, L. H., McCarty, P. L., Kitanidis, P. K. 1998; 64 (6): 2044-2050

  View details for Web of Science ID 000073904800009

• Remediation technology transfer from full-scale demonstration to implementation: A case study of trichloroethylene bioremediation FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 1 Mandalas, G. C., Christ, J. A., Hopkins, G. D., McCarty, P. L., Goltz, M. N. 1998: 235-240

  View details for Web of Science ID 000075845900039

• Full scale evaluation of in situ cometabolic degradation of trichloroethylene in groundwater through toluene injection ENVIRONMENTAL SCIENCE & TECHNOLOGY Mccarty, P. L., Goltz, M. N., Hopkins, G. D., Dolan, M. E., Allan, J. P., Kawakami, B. T., Carrothers, T. J. 1998; 32 (1): 88-100

  View details for Web of Science ID 000071284200035

• Design of an in-situ injection/extraction bioremediation system FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 6 Kawakami, B. T., Christ, J., Goltz, M. N., McCarty, P. L. 1998: 33-38

  View details for Web of Science ID 000075849600006

• In vitro studies on reductive vinyl chloride dehalogenation by an anaerobic mixed culture APPLIED AND ENVIRONMENTAL MICROBIOLOGY Rosner, B. M., McCarty, P. L., Spormann, A. M. 1997; 63 (11): 4139-4144

  Abstract

  Reductive dehalogenation of vinyl chloride (VC) was studied in an anaerobic mixed bacterial culture. In growth experiments, ethene formation from VC increased exponentially at a rate of about 0.019 h(sup-1). Reductive VC dehalogenation was measured in vitro by using cell extracts of the mixed culture. The apparent K(infm) for VC was determined to be about 76 (mu)M; the V(infmax) was about 28 nmol (middot) min(sup-1) (middot) mg of protein(sup-1). The VC-dehalogenating activity was membrane associated. Propyl iodide had an inhibitory effect on the VC-dehalogenating activity in the in vitro assay. However, this inhibition could not be reversed by illumination. Cell extracts also catalyzed the reductive dehalogenation of cis-1,2-dichloroethene (cis-DCE) and, at a lower rate, of trichloroethene (TCE). Tetrachloroethene (PCE) was not transformed. The results indicate that the reductive dehalogenation of VC and cis-DCE described here is different from previously reported reductive dehalogenation of PCE and TCE.

  View details for Web of Science ID A1997YE28100001

  View details for PubMedID 16535722

• Development and evaluation of semicontinuous slurry microcosms to simulate in situ biodegradation of trichloroethylene in contaminated aquifers ENVIRONMENTAL SCIENCE & TECHNOLOGY JENALWANNER, U., McCarty, P. L. 1997; 31 (10): 2915-2922

  View details for Web of Science ID A1997XZ78700055

• Laboratory evaluation of a two-stage treatment system for TCE cometabolism by a methane-oxidizing mixed culture BIOTECHNOLOGY AND BIOENGINEERING Smith, L. H., McCarty, P. L. 1997; 55 (4): 650-659

  Abstract

  The objective of this research was to evaluate several factors affecting the performance of a two-stage treatment system employing methane-oxidizing bacteria for trichloroethylene (TCE) biodegradation. The system consists of a completely mixed growth reactor and a plug-flow transformation reactor in which the TCE is cometabolized. Laboratory studies were conducted with continuous growth reactors and batch experiments simulating transformation reactor conditions. Performance was characterized in terms of TCE transformation capacity (T(C), g TCE/g cells), transformation yield (T(Y), g TCE/g CH(4)), and the rate coefficient ratio k(TCE)/K(S,TCE) (L/mg-d). The growth reactor variables studied were solids retention time (SRT) and nutrient nitrogen (N) concentration. Formate and methane were evaluated as potential transformation reactor amendments. Comparison of cultures from 2- and 8-day SRT (nitrogen-limited) growth reactors indicated that there was no significant effect of growth reactor SRT or nitrogen availability on T(C) or T(Y), but N-limited conditions yielded higher k(TCE)/K(S,TCE). The TCE cometabolic activity of the 8-day SRT, N-limited growth reactor culture varied significantly during a 7-year period of operation. The T(C) and T(Y) of the resting cells increased gradually to levels a factor of 2 higher than the initial values. The reasons for this increase are unknown. Formate addition to the transformation reactor gave higher T(C) and T(Y) for 2-day SRT growth reactor conditions and significantly lower T(C), T(Y), and k(TCE)/K(S,TCE) for 8-day SRT N-limited conditions. Methane addition to the transformation reactor inhibited TCE cometabolism at low TCE concentrations and enhanced TCE cometabolism at high TCE concentrations, indicating that the TCE cometabolism in the presence of methane does not follow simple competitive inhibition kinetics. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 650-659, 1997.

  View details for Web of Science ID A1997XM21300007

  View details for PubMedID 18636575

• Effect of chlorinated ethenes on S-min for a methanotrophic mixed culture ENVIRONMENTAL SCIENCE & TECHNOLOGY Anderson, J. E., McCarty, P. L. 1997; 31 (8): 2204-2210

  View details for Web of Science ID A1997XN75800034

• A novel means to develop strain-specific DNA probes for detecting bacteria in the environment APPLIED AND ENVIRONMENTAL MICROBIOLOGY MATHESON, V. G., MunakataMarr, J., Hopkins, G. D., McCarty, P. L., Tiedje, J. M., Forney, L. J. 1997; 63 (7): 2863-2869

  Abstract

  A simple means to develop strain-specific DNA probes for use in monitoring the movement and survival of bacteria in natural and laboratory ecosystems was developed. The method employed amplification of genomic DNA via repetitive sequence-based PCR (rep-PCR) using primers specific for repetitive extragenic palindromic (REP) elements, followed by cloning of the amplified fragments. The cloned fragments were screened to identify those which were strain specific, and these were used as probes for total genomic DNA isolated from microbial communities and subjected to rep-PCR. To evaluate the utility of the approach, we developed probes specific for Burkholderia cepacia G4 and used them to determine the persistence of the strain in aquifer sediment microcosms following bioaugmentation. Two of four probes tested were found to specifically hybridize to DNA fragments of the expected sizes in the rep-PCR fingerprint of B. cepacia G4 but not to 64 genetically distinct bacteria previously isolated from the aquifer. One of these probes, a 650-bp fragment, produced a hybridization signal when as few as 10 CFU of B. cepacia G4 were present in a mixture with 10(6) CFU nontarget strains, indicating that the sensitivity of these probes was comparable to those of other PCR-based detection methods. The probes were used to discriminate groundwater and microcosm samples that contained B. cepacia G4 from those which did not. False-positive results were obtained with a few samples, but these were readily identified by using hybridization to the second probe as a confirmation step. The general applicability of the method was demonstrated by constructing probes specific to three other environmental isolates.

  View details for Web of Science ID A1997XJ18200055

  View details for PubMedID 9212434

• Microbial succession during a field evaluation of phenol and toluene as the primary substrates for trichloroethene cometabolism APPLIED AND ENVIRONMENTAL MICROBIOLOGY Fries, M. R., Hopkins, G. D., McCarty, P. L., Forney, L. J., Tiedje, J. M. 1997; 63 (4): 1515-1522

  Abstract

  Microbial community composition and succession were studied in an aquifer that was amended with phenol, toluene, and chlorinated aliphatic hydrocarbons to evaluate the effectiveness of these aromatic substrates for stimulating trichloroethene (TCE) bioremediation. Samples were taken after the previous year's field studies, which used phenol as the primary substrate, and after three successive monthly treatments of phenol plus 1,1-dichloroethene (1,1-DCE) plus TCE, phenol plus TCE, and toluene plus TCE. Dominant eubacteria in the community were assessed after each of the four treatments by characterizing isolates from the most dilute most-probable-number tubes and by extracting DNA from aquifer samples. The succession of dominant phenol- and toluene-degrading strains was evaluated by genomic fingerprinting, cellular fatty acid methyl ester (FAME) analysis, and amplified ribosomal DNA restriction analysis (ARDRA). 1,1-DCE was found to drastically reduce microbial growth and species richness, which corresponded to the reduction in bioremediation effectiveness noted previously for this treatment (G. D. Hopkins and P. L. McCarty, Environ. Sci. Technol. 29:1628-1637, 1995). Only a few gram-positive isolates could be obtained after treatment with 1,1-DCE, and these were not seen after any other treatments. Microbial densities returned to their original levels following the subsequent phenol-TCE treatment, but the original species richness was not restored until after the subsequent toluene-TCE treatment. Genomic fingerprinting and FAME analysis indicated that six of the seven originally dominant microbial groups were still dominant after the last treatment, indicating that the community is quite resilient to toxic disturbance by 1,1-DCE. FAME analysis indicated that six microbial taxa were dominant: three members of the (beta) subclass of the class Proteobacteria (Comamonas-Variovorax, Azoarcus, and Burkholderia) and three gram-positive groups (Bacillus, Nocardia, and an unidentified group). ARDRA revealed that the dominant community members were stable during the three nontoxic treatments and that virtually all of the bands could be accounted for by isolates from five of the dominant taxa, indicating that the isolation protocol used likely recovered most of the dominant members of this community.

  View details for Web of Science ID A1997WR16200048

  View details for PubMedID 16535576

• Long-term biodegradation of trichloroethylene influenced by bioaugmentation and dissolved oxygen in aquifer microcosms ENVIRONMENTAL SCIENCE & TECHNOLOGY MunakataMarr, J., MATHESON, V. G., Forney, L. J., Tiedje, J. M., McCarty, P. L. 1997; 31 (3): 786-791

  View details for Web of Science ID A1997WK81500052

• Numerical modeling and uncertainties in rate coefficients for methane utilization and TCE cometabolism by a methane-oxidizing mixed culture BIOTECHNOLOGY AND BIOENGINEERING Smith, L. H., Kitanidis, P. K., McCarty, P. L. 1997; 53 (3): 320-331

  Abstract

  The rates of methane utilization and trichloroethylene (TCE) cometabolism by a methanotrophic mixed culture were characterized in batch and pseudo-steady-state studies. Procedures for determination of the rate coefficients and their uncertainties by fitting a numerical model to experimental data are described. The model consisted of a system of differential equations for the rates of Monod kinetics, cell growth on methane and inactivation due to TCE transformation product toxicity, gas/liquid mass transfer of methane and TCE, and the rate of passive losses of TCE. The maximum specific rate of methane utilization (k(CH(4) )) was determined by fitting the numerical model to batch experimental data, with the initial concentration of active methane-oxidizing cells (X(0) (a)) also used as a model fitting parameter. The best estimate of k(CH(4) ) was 2.2 g CH(4)/g cells-d with excess copper available, with a single-parameter 95% confidence interval of 2.0-2.4 mg/mg-d. The joint 95% confidence region for k(CH(4) ) and X(0) (a) is presented graphically. The half-velocity coefficient (K(S,CH(4) )) was 0.07 mg CH(4)/L with excess copper available and 0.47 mg CH(4)/L under copper limitation, with 95% confidence intervals of 0.02-0.11 and 0.35-0.59 mg/L, respectively. Unique values of the TCE rate coefficients k(TCE) and K(S,TCE) could not be determined because they were found to be highly correlated in the model fitting analysis. However, the ratio k(TCE)/K(S,TCE) and the TCE transformation capacity (T(C)) were well defined, with values of 0.35 L/mg-day and 0.21 g TCE/g active cells, respectively, for cells transforming TCE in the absence of methane or supplemental formate. The single-parameter 95% confidence intervals for k(TCE)/K(S,TCE) and T(C) were 0.27-0.43 L/mg-d and 0.18-0.24 g TCE/g active cells, respectively. The joint 95% confidence regions for k(TCE)/K(S,TCE) and T(C) are presented graphically.

  View details for Web of Science ID A1997WG06900011

  View details for PubMedID 18633987

• Bioaugmentation with Burkholderia cepacia: Trichloroethylene cometabolism vs. colonization IN SITU AND ON-SITE BIOREMEDIATION, VOL 4 MunakataMarr, J., MATHESON, V. G., Forney, L. J., Tiedje, J. M., McCarty, P. L. 1997; 4(4): 501-506

  View details for Web of Science ID A1997BH89V00112

• The environmental engineering and science program at Stanford University McCarty, P. AMERICAN ACADEMY ENVIRONMENTAL ENGINEERS. 1997: 51-53

  View details for Web of Science ID A1997BJ39E00009

• Enhancement of trichloroethylene degradation in aquifer microcosms bioaugmented with wild type and genetically altered Burkholderia (Pseudomonas) cepacia G4 and PR1 ENVIRONMENTAL SCIENCE & TECHNOLOGY MunakataMarr, J., McCarty, P. L., Shields, M. S., Reagin, M., Francesconi, S. C. 1996; 30 (6): 2045-2052

  View details for Web of Science ID A1996UM99100056

• Isolation and characterization of a facultatively aerobic bacterium that reductively dehalogenates tetrachloroethene to cis-1,2-dichloroethene APPLIED AND ENVIRONMENTAL MICROBIOLOGY Sharma, P. K., McCarty, P. L. 1996; 62 (3): 761-765

  Abstract

  A rapidly-growing facultatively aerobic bacterium that transforms tetrachloroethene (PCE) via trichloroethene (TCE) to cis-1,2-dichloroethene (cis-1,2-DCE) at high rates in a defined medium was isolated from a contaminated site. Metabolic characterization, cellular fatty acid analysis, and partial sequence analysis of 16S rRNA showed that the new isolate, strain MS-1, has characteristics matching those of the members of the family Enterobacteriaceae. Strain MS-1 can oxidize about 58 substrates including many carbohydrates, short-chain fatty acids, amino acids, purines, and pyrimidines. It can transform up to 1 mM PCE (aqueous) at a rate of about 0.5 (mu)mol of PCE(middot) h(sup-1)(middot)mg (dry weight) of cell(sup-1). PCE transformation occurs following growth on or with the addition of single carbon sources such as glucose, pyruvate, formate, lactate, or acetate or with complex nutrient sources such as yeast extract or a mixture of amino acids. PCE dehalogenation requires the absence of oxygen, nitrate, and high concentrations of fermentable compounds such as glucose. Enterobacter agglomerans biogroup 5 (ATCC 27993), a known facultative bacterium that is closely related to strain MS-1, also reductively dehalogenated PCE to cis-1,2-DCE. To our knowledge, this is the first report on isolation of a facultative bacterium that can reductively transform PCE to cis-1,2-DCE under defined physiological conditions. Also, this is the first report of the ability of E. agglomerans to dehalogenate PCE.

  View details for Web of Science ID A1996TY36500003

  View details for PubMedID 16535267

• Transferability of biotreatment from site to site McCarty, P. L. ORGANIZATION ECONOMIC COOPERATION & DEVELOPMENT. 1996: 201-210

  View details for Web of Science ID A1996BG53M00020

• APPARATUS FOR DOWN-WELL OXYGEN-TRANSFER INTO CONTAMINATED AQUIFERS JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE Bae, J. H., Semprini, L., McCarty, P. L. 1995; 121 (8): 565-570

  View details for Web of Science ID A1995RK48500004

• SMALL COLUMN MICROCOSM FOR ASSESSING METHANE-STIMULATED VINYL-CHLORIDE TRANSFORMATION IN AQUIFER SAMPLES ENVIRONMENTAL SCIENCE & TECHNOLOGY Dolan, M. E., McCarty, P. L. 1995; 29 (8): 1892-1897

  View details for Web of Science ID A1995RL82900027

  View details for PubMedID 22191334

• FIELD-EVALUATION OF IN-SITU AEROBIC COMETABOLISM OF TRICHLOROETHYLENE AND 3 DICHLOROETHYLENE ISOMERS USING PHENOL AND TOLUENE AS THE PRIMARY SUBSTRATES ENVIRONMENTAL SCIENCE & TECHNOLOGY Hopkins, G. D., McCarty, P. L. 1995; 29 (6): 1628-1637

  View details for Web of Science ID A1995RB13100046

  View details for PubMedID 22276888

• MODEL FOR TREATMENT OF TRICHLOROETHYLENE BY METHANOTROPHIC BIOFILMS JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE Anderson, J. E., McCarty, P. L. 1994; 120 (2): 379-400

  View details for Web of Science ID A1994NC98700008

• FACTORS AFFECTING TRANSFORMATION OF CHLORINATED ALIPHATIC HYDROCARBONS BY METHANOTROPHS Dolan, M. E., McCarty, P. L. LEWIS PUBLISHERS INC. 1994: 303-308

  View details for Web of Science ID A1994BC30T00030

• A FIELD AND MODELING COMPARISON OF INSITU TRANSFORMATION OF TRICHLOROETHYLENE BY METHANE UTILIZERS AND PHENOL UTILIZERS BIOREMEDIATION OF CHLORINATED AND POLYCYCLIC AROMATIC HYDROCARBON COMPOUNDS Semprini, L., Hopkins, G. D., McCarty, P. L. 1994: 248-254

  View details for Web of Science ID A1994BC30T00021

• VARIATION OF CARBON-MONOXIDE PRODUCTION DURING METHANE FERMENTATION OF GLUCOSE WATER ENVIRONMENT RESEARCH Bae, J. H., McCarty, P. L. 1993; 65 (7): 890-898

  View details for Web of Science ID A1993MK51100011

• TRICHLOROETHYLENE CONCENTRATION EFFECTS ON PILOT FIELD-SCALE IN-SITU GROUNDWATER BIOREMEDIATION BY PHENOL-OXIDIZING MICROORGANISMS ENVIRONMENTAL SCIENCE & TECHNOLOGY Hopkins, G. D., Munakata, J., Semprini, L., McCarty, P. L. 1993; 27 (12): 2542-2547

  View details for Web of Science ID A1993ME57800049

• SORPTION OF TRICHLOROETHYLENE ONTO A ZEOLITE ACCOMPANIED BY METHANOTROPHIC BIOTRANSFORMATION ENVIRONMENTAL SCIENCE & TECHNOLOGY Alvarez-Cohen, L., McCarty, P. L., Roberts, P. V. 1993; 27 (10): 2141-2148

  View details for Web of Science ID A1993LZ74900028

• ENGINEERING AND HYDROGEOLOGICAL PROBLEMS ASSOCIATED WITH IN-SITU TREATMENT McCarty, P. L., Semprini, L. IAHS PRESS, INST HYDROLOGY. 1993: 261-272

  View details for Web of Science ID A1993MH63600002

• MICROCOSM AND IN-SITU FIELD STUDIES OF ENHANCED BIOTRANSFORMATION OF TRICHLOROETHYLENE BY PHENOL-UTILIZING MICROORGANISMS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Hopkins, G. D., Semprini, L., McCarty, P. L. 1993; 59 (7): 2277-2285

  Abstract

  The ability of different aerobic groundwater microorganisms to cometabolically degrade trichloroethylene (TCE), 1,2-cis-dichloroethylene (c-DCE), and 1,2-trans-dichloroethylene (t-DCE) was evaluated both in groundwater-fed microcosms and in situ in a shallow aquifer. Microcosms amended with phenol or toulene were equally effective in removing c-DCE (> 90%) followed by TCE (60 to 70%), while the microcosm fed methane was most effective in removing t-DCE (> 90%). The microcosm fed ammonia was the least effective. None of the microcosms effectively degraded 1,1,1-trichloroethane. At the Moffett Field groundwater test site, in situ removal of c-DCE and TCE coincided with biostimulation through phenol and oxygen injection and utilization, with c-DCE removed more rapidly than TCE. Greater TCE and c-DCE removal was observed when the phenol concentration was increased. Over 90% removal of c-DCE and TCE was observed in the 2-m biostimulated zone. This compares with 40 to 50% removal of c-DCE and 15 to 25% removal of TCE achieved by methane-grown microorganisms previously evaluated in an adjacent in situ test zone. The in situ removal with phenol-grown microorganisms agrees qualitatively with the microcosm studies, with the rates and extents of removal ranked as follows: c-DCE > TCE > t-DCE. These studies demonstrate the potential for in situ TCE bioremediation using microorganisms grown on phenol.

  View details for Web of Science ID A1993LL31000043

  View details for PubMedID 8357259

• INFLUENCE OF THE ENDOGENOUS STORAGE LIPID POLY-BETA-HYDROXYBUTYRATE ON THE REDUCING POWER-AVAILABILITY DURING COMETABOLISM OF TRICHLOROETHYLENE AND NAPHTHALENE BY RESTING METHANOTROPHIC MIXED CULTURES APPLIED AND ENVIRONMENTAL MICROBIOLOGY Henrysson, T., McCarty, P. L. 1993; 59 (5): 1602-1606

  Abstract

  The role of the storage lipid poly-beta-hydroxybutyrate (PHB) in trichloroethylene transformation by methanotrophic mixed cultures was investigated. Naphthalene oxidation rates were used to assay for soluble methane monooxygenase activity. The PHB content of methanotrophic cells grown in reactors varied diurnally as well as from day to day. A positive correlation between the amount of PHB in the cells and the naphthalene oxidation rate as well as between PHB and the trichloroethylene transformation rate and capacity was found. Addition of beta-hydroxybutyrate increased the naphthalene oxidation rates significantly. PHB content in cells could be manipulated by incubation at different methane-to-nitrogen ratios. A positive correlation between the naphthalene oxidation rate and the PHB content after these incubations could be seen. Both the PHB content and the naphthalene oxidation rates decreased with time in resting methanotrophic cells exposed to oxygen. However, this decrease in the naphthalene oxidation rate cannot be explained by the decrease in the PHB content alone. Probably a deactivation of the methane monooxygenase itself is also involved.

  View details for Web of Science ID A1993LA78000052

  View details for PubMedID 16348940

• INHIBITION OF BUTYRATE OXIDATION BY FORMATE DURING METHANOGENESIS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Bae, J., McCarty, P. L. 1993; 59 (2): 628-630

  Abstract

  A mixed methanogenic culture fed with glucose was perturbed with butyrate and formate to investigate the role of formate in the acetogenesis of butyrate. A free energy analysis suggests that formate rather than H(2) was the interspecies electron carrier for butyrate conversion into acetate for the culture studied.

  View details for Web of Science ID A1993KK91600047

  View details for PubMedID 16348880

• BIOLOGICAL AND CHEMICAL-TRANSFORMATIONS OF HALOGENATED ALIPHATIC-COMPOUNDS IN AQUATIC AND TERRESTRIAL ENVIRONMENTS BIOGEOCHEMISTRY OF GLOBAL CHANGE McCarty, P. L., Reinhard, M. 1993: 839-852

  View details for Web of Science ID A1993BZ08Y00045

• PILOT SCALE FIELD STUDIES OF INSITU BIOREMEDIATION OF CHLORINATED SOLVENTS Semprini, L., Hopkins, G. D., Roberts, P. V., McCarty, P. L. ELSEVIER SCIENCE BV. 1992: 145-162

  View details for Web of Science ID A1992KG51500004

• INSITU TRANSFORMATION OF CARBON-TETRACHLORIDE AND OTHER HALOGENATED COMPOUNDS RESULTING FROM BIOSTIMULATION UNDER ANOXIC CONDITIONS ENVIRONMENTAL SCIENCE & TECHNOLOGY Semprini, L., Hopkins, G. D., McCarty, P. L., Roberts, P. V. 1992; 26 (12): 2454-2461

  View details for Web of Science ID A1992KA32800025

• CHARACTERIZATION OF A METHANE-UTILIZING BACTERIUM FROM A BACTERIAL CONSORTIUM THAT RAPIDLY DEGRADES TRICHLOROETHYLENE AND CHLOROFORM APPLIED AND ENVIRONMENTAL MICROBIOLOGY Alvarez-Cohen, L., McCarty, P. L., BOULYGINA, E., Hanson, R. S., Brusseau, G. A., TSIEN, H. C. 1992; 58 (6): 1886-1893

  Abstract

  A mixed culture of bacteria grown in a bioreactor with methane as a carbon and energy source rapidly oxidized trichloroethylene and chloroform. The most abundant organism was a crescent-shaped bacterium that bound the fluorescent oligonucleotide signature probes that specifically hybridize to serine pathway methylotrophs. The 5S rRNA from this bacterium was found to be 93.5% homologous to the Methylosinus trichosporium OB3b 5S RNA sequence. A type II methanotrophic bacterium, isolated in pure culture from the bioreactor, synthesized soluble methane monooxygenase during growth in a copper-limited medium and was also capable of rapid trichloroethylene oxidation. The bacterium contained the gene that encodes the soluble methane monooxygenase B component on an AseI restriction fragment identical in size to a restriction fragment present in AseI digests of DNA from bacteria in the mixed culture. The sequence of the 16S rRNA from the pure culture was found to be 92 and 94% homologous to the 16S rRNAs of M. trichosporium OB3b and M. sporium, respectively. Both the pure and mixed cultures oxidized naphthalene to naphthol, indicating the presence of soluble methane monooxygenase. The mixed culture also synthesized soluble methane monooxygenase, as evidenced by the presence of proteins that cross-reacted with antibodies prepared against purified soluble methane monooxygenase components from M. trichosporium OB3b on Western blots (immunoblots). It was concluded that a type II methanotrophic bacterium phylogenetically related to Methylosinus species synthesizes soluble methane monooxygenase and is responsible for trichloroethylene oxidation in the bioreactor.

  View details for Web of Science ID A1992HX94500015

  View details for PubMedID 1377902

• COMPARISON BETWEEN MODEL SIMULATIONS AND FIELD RESULTS FOR INSITU BIORESTORATION OF CHLORINATED ALIPHATICS .2. COMETABOLIC TRANSFORMATIONS GROUND WATER Semprini, L., McCarty, P. L. 1992; 30 (1): 37-44

  View details for Web of Science ID A1992GX62600006

• TERRESTRIAL PHYSICAL AND CHEMICAL PROCESSES FOR LIQUID WASTE TREATMENT McCarty, P. L. ACADEMIC PRESS LTD. 1991: 379-387

  Abstract

  Experiences gained from full-scale evaluation of advanced treatment processes used for reclaiming wastewaters should help in the evaluation of potential treatment systems for treatment and reuse of water in space. Water Factory 21 is a 0.66 m3 s-1 (15 million gallons per day) water reclamation plant in California that has been in operation since 1976. The plant receives biologically treated wastewater. Lime treatment is effective for removal of heavy metals. Volatile organic constitutes are efficiently removed by air stripping. Non-volatile organic constituents are removed by activated carbon adsorption and reverse osmosis (RO). RO is a highly effective polishing step, and removes most of the remaining materials including inorganic salts, heavy metals, and organics. RO removed 85% of the total organic carbon, down to about 1 mg l-1, which is lower than in many treated drinking waters. The series of treatment processes used insured virus and pathogen removal, with lime treatment and chlorination together proving highly effective. Sufficient data has been collected to provide statistically reliable confidence limits to be set on the performance of each unit process.

  View details for Web of Science ID A1991GR06500010

  View details for PubMedID 11537689

• ENGINEERING CONCEPTS FOR INSITU BIOREMEDIATION McCarty, P. L. ELSEVIER SCIENCE BV. 1991: 1-11

  View details for Web of Science ID A1991GM76600002

• A COMETABOLIC BIOTRANSFORMATION MODEL FOR HALOGENATED ALIPHATIC-COMPOUNDS EXHIBITING PRODUCT TOXICITY ENVIRONMENTAL SCIENCE & TECHNOLOGY Alvarez-Cohen, L., McCarty, P. L. 1991; 25 (8): 1381-1387

  View details for Web of Science ID A1991FY99800009

• 2-STAGE DISPERSED-GROWTH TREATMENT OF HALOGENATED ALIPHATIC-COMPOUNDS BY COMETABOLISM ENVIRONMENTAL SCIENCE & TECHNOLOGY Alvarez-Cohen, L., McCarty, P. L. 1991; 25 (8): 1387-1393

  View details for Web of Science ID A1991FY99800010

• ELECTROLYTIC MODEL SYSTEM FOR REDUCTIVE DEHALOGENATION IN AQUEOUS ENVIRONMENTS ENVIRONMENTAL SCIENCE & TECHNOLOGY Criddle, C. S., McCarty, P. L. 1991; 25 (5): 973-978

  View details for Web of Science ID A1991FK08300028

• COMPARISON BETWEEN MODEL SIMULATIONS AND FIELD RESULTS FOR INSITU BIORESTORATION OF CHLORINATED ALIPHATICS .1. BIOSTIMULATION OF METHANOTROPHIC BACTERIA GROUND WATER Semprini, L., McCarty, P. L. 1991; 29 (3): 365-374

  View details for Web of Science ID A1991FJ70000006

• PRODUCT TOXICITY AND COMETABOLIC COMPETITIVE-INHIBITION MODELING OF CHLOROFORM AND TRICHLOROETHYLENE TRANSFORMATION BY METHANOTROPHIC RESTING CELLS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Alvarez-Cohen, L., McCarty, P. L. 1991; 57 (4): 1031-1037

  Abstract

  The rate and capacity for chloroform (CF) and trichloroethylene (TCE) transformation by a mixed methanotrophic culture of resting cells (no exogenous energy source) and formate-fed cells were measured. As reported previously for TCE, formate addition resulted in an increased CF transformation rate (0.35 day-1 for resting cells and 1.5 day-1 for formate-fed cells) and transformation capacity (0.0065 mg of CF per mg of cells for resting cells and 0.015 mg of CF per mg of cells for formate-fed cells), suggesting that depletion of energy stores affects transformation behavior. The observed finite transformation capacity, even with an exogenous energy source, suggests that toxicity was also a factor. CF transformation capacity was significantly lower than that for TCE, suggesting a greater toxicity from CF transformation. The toxicity of CF, TCE, and their transformation products to whole cells was evaluated by comparing the formate oxidation activity of acetylene-treated cells to that of non-acetylene-treated cells with and without prior exposure to CF or TCE. Acetylene arrests the activity of methane monooxygenase in CF and TCE oxidation without halting cell activity toward formate. Significantly diminished formate oxidation by cells exposed to either CR or TCE without acetylene compared with that with acetylene suggests that the solvents themselves were not toxic under the experimental conditions but their transformation products were. The concurrent transformation of CF and TCE by resting cells was measured, and results were compared with predictions from a competitive-inhibition cometabolic transformation model. The reasonable fit between model predictions and experimental observations was supportive of model assumptions.

  View details for Web of Science ID A1991FF03900023

  View details for PubMedID 1905516

• A FIELD-EVALUATION OF INSITU BIODEGRADATION OF CHLORINATED ETHENES .3. STUDIES OF COMPETITIVE-INHIBITION GROUND WATER Semprini, L., Hopkins, G. D., Roberts, P. V., GRBICGALIC, D., McCarty, P. L. 1991; 29 (2): 239-250

  View details for Web of Science ID A1991FA88300012

• INSITU METHANOTROPHIC BIOREMEDIATION FOR CONTAMINATED GROUNDWATER AT ST-JOSEPH, MICHIGAN McCarty, P. L., Semprini, L., Dolan, M. E., Harmon, T. C., TIEDEMAN, C., Gorelick, S. M. BUTTERWORTH-HEINEMANN. 1991: 16-40

  View details for Web of Science ID A1991BU85J00002

• EFFECTS OF TOXICITY, AERATION, AND REDUCTANT SUPPLY ON TRICHLOROETHYLENE TRANSFORMATION BY A MIXED METHANOTROPHIC CULTURE APPLIED AND ENVIRONMENTAL MICROBIOLOGY Alvarez-Cohen, L., McCarty, P. L. 1991; 57 (1): 228-235

  Abstract

  The trichloroethylene (TCE) transformation rate and capacity of a mixed methanotrophic culture at room temperature were measured to determine the effects of time without methane (resting), use of an alternative energy source (formate), aeration, and toxicity of TCE and its transformation products. The initial specific TCE transformation rate of resting cells was 0.6 mg of TCE per mg of cells per day, and they had a finite TCE transformation capacity of 0.036 mg of TCE per mg of cells. Formate addition resulted in increased initial specific TCE transformation rates (2.1 mg/mg of cells per day) and elevated transformation capacity (0.073 mg of TCE per mg of cells). Significant declines in methane conversion rates following exposure to TCE were observed for both resting and formate-fed cells, suggesting toxic effects caused by TCE or its transformation products. TCE transformation and methane consumption rates of resting cells decreased with time much more rapidly when cells were shaken and aerated than when they remained dormant, suggesting that the transformation ability of methanotrophs is best preserved by storage under anoxic conditions.

  View details for Web of Science ID A1991ER20600035

  View details for PubMedID 2036009

• DEGRADATION OF TOLUENE AND PARA-XYLENE IN ANAEROBIC MICROCOSMS - EVIDENCE FOR SULFATE AS A TERMINAL ELECTRON-ACCEPTOR ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY Haag, F., Reinhard, M., McCarty, P. L. 1991; 10 (11): 1379-1389

  View details for Web of Science ID A1991GM68800002

• BIOTRANSFORMATION OF MONOAROMATIC HYDROCARBONS UNDER ANOXIC CONDITIONS Ball, H. A., Reinhard, M., McCarty, P. L. BUTTERWORTH-HEINEMANN. 1991: 458-463

  View details for Web of Science ID A1991BU85H00030

• INSITU BIOTRANSFORMATION OF CARBON-TETRACHLORIDE, FREON-113, FREON-11, AND 1,1,1-TCA UNDER ANOXIC CONDITIONS Semprini, L., Hopkins, G. D., Roberts, P. V., McCarty, P. L. BUTTERWORTH-HEINEMANN. 1991: 41-58

  View details for Web of Science ID A1991BU85J00003

• MODELING OF ANAEROBIC-DIGESTION PROCESSES (A DISCUSSION OF CONCEPTS) McCarty, P. L., MOSEY, F. E. IWA PUBLISHING. 1991: 17-33

  View details for Web of Science ID A1991GG35900004

• TRANSFORMATION OF CARBON-TETRACHLORIDE BY PSEUDOMONAS SP STRAIN KC UNDER DENITRIFICATION CONDITIONS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Criddle, C. S., DEWITT, J. T., GRBICGALIC, D., McCarty, P. L. 1990; 56 (11): 3240-3246

  Abstract

  A denitrifying Pseudomonas sp. (strain KC) capable of transforming carbon tetrachloride (CT) was isolated from groundwater aquifer solids. Major products of the transformation of 14C-labeled CT by Pseudomonas strain KC under denitrification conditions were 14CO2 and an unidentified water-soluble fraction. Little or no chloroform was produced. Addition of dissolved trace metals, notably, ferrous iron and cobalt, to the growth medium appeared to enhance growth of Pseudomonas strain KC while inhibiting transformation of CT. It is hypothesized that transformation of CT by this organism is associated with the mechanism of trace-metal scavenging.

  View details for Web of Science ID A1990EF66300002

  View details for PubMedID 2268146

• COLUMN STUDIES ON METHANOTROPHIC DEGRADATION OF TRICHLOROETHENE AND 1,2-DICHLOROETHANE GROUND WATER LANZARONE, N. A., McCarty, P. L. 1990; 28 (6): 910-919

  View details for Web of Science ID A1990EG55900009

• REDUCTIVE DEHALOGENATION OF CARBON-TETRACHLORIDE BY ESCHERICHIA-COLI K-12 APPLIED AND ENVIRONMENTAL MICROBIOLOGY Criddle, C. S., DEWITT, J. T., McCarty, P. L. 1990; 56 (11): 3247-3254

  Abstract

  The formation of radicals from carbon tetrachloride (CT) is often invoked to explain the product distribution resulting from its transformation. Radicals formed by reduction of CT presumably react with constituents of the surrounding milieu to give the observed product distribution. The patterns of transformation observed in this work were consistent with such a hypothesis. In cultures of Escherichia coli K-12, the pathways and rates of CT transformation were dependent on the electron acceptor condition of the media. Use of oxygen and nitrate as electron acceptors generally prevented CT metabolism. At low oxygen levels (approximately 1%), however, transformation of [14C]CT to 14CO2 and attachment to cell material did occur, in accord with reports of CT fate in mammalian cell cultures. Under fumarate-respiring conditions, [14C]CT was recovered as 14CO2, chloroform, and a nonvolatile fraction. In contrast, fermenting conditions resulted in more chloroform, more cell-bound 14C, and almost no 14CO2. Rates of transformation of CT were faster under fermenting conditions than under fumarate-respiring conditions. Transformation rates also decreased over time, suggesting the gradual exhaustion of transformation activity. This loss was modeled with a simple exponential decay term.

  View details for Web of Science ID A1990EF66300003

  View details for PubMedID 2268147

• A FIELD-EVALUATION OF INSITU BIODEGRADATION OF CHLORINATED ETHENES .2. RESULTS OF BIOSTIMULATION AND BIOTRANSFORMATION EXPERIMENTS GROUND WATER Semprini, L., Roberts, P. V., Hopkins, G. D., McCarty, P. L. 1990; 28 (5): 715-727

  View details for Web of Science ID A1990DY03900008

• METHANE FERMENTATION OF SELECTED LIGNOCELLULOSIC MATERIALS BIOMASS Tong, X. G., Smith, L. H., McCarty, P. L. 1990; 21 (4): 239-255

  View details for Web of Science ID A1990CW95100001

• FACTORS GOVERNING METHANE FLUCTUATIONS FOLLOWING SHOCK LOADING OF DIGESTERS RESEARCH JOURNAL OF THE WATER POLLUTION CONTROL FEDERATION Smith, D. P., McCarty, P. L. 1990; 62 (1): 58-64

  View details for Web of Science ID A1990CK43800008

• REDUCED PRODUCT FORMATION FOLLOWING PERTURBATION OF ETHANOL-FED AND PROPIONATE-FED METHANOGENIC CSTRS BIOTECHNOLOGY AND BIOENGINEERING Smith, D. P., McCarty, P. L. 1989; 34 (7): 885-895

  Abstract

  Energetic analysis was applied to reduced product formation following perturbation of ethanol- and propionate-fed methanogenic continuous stirred tank reactors (CSTRs). Formation and dissipation of longer-chained n-carboxylic acids corresponded with the variation in Gibbs free energy change associated with beta-oxidation reactions. Formation appeared to occur from acetate and propionate by reductive back-reactions, made energetically favorable by elevated hydrogen partial pressure (P(H(2))), and possibly mediated by biosynthetic enzymes. The formed longer-chained acids dissipated when the P(H(2)) fell and equilibrium shifted to favor beta-oxidations. n-Propanol was found to be produced from propionate in a coupled ethanol oxidation/propionate reduction reaction, mediated by ethanol-oxidizing organisms during high rates of ethanol utilization and elevated P(H(2)). When P(H(2)) declined, n-propanol was oxidized back to its precursor propionate. Both reaction energetics and intracellular diffusion of the electron carrier may effect transient mediation of this coupled reaction.

  View details for Web of Science ID A1989AQ78100001

  View details for PubMedID 18588179

• BIOTRANSFORMATION OF HALOGENATED AND NONHALOGENATED OCTYLPHENOL POLYETHOXYLATE RESIDUES UNDER AEROBIC AND ANAEROBIC CONDITIONS ENVIRONMENTAL SCIENCE & TECHNOLOGY Ball, H. A., Reinhard, M., McCarty, P. L. 1989; 23 (8): 951-961

  View details for Web of Science ID A1989AH87000011

• ENERGETIC AND RATE EFFECTS ON METHANOGENESIS OF ETHANOL AND PROPIONATE IN PERTURBED CSTRS BIOTECHNOLOGY AND BIOENGINEERING Smith, D. P., McCarty, P. L. 1989; 34 (1): 39-54

  Abstract

  Energetic and reaction-rate interactions between hydrogenic (hydrogen-producing) and hydrogenotrophic (hydrogen-consuming) bacteria were investigated in five perturbation experiments performed on steady-state, mixed-culture methanogenic CSTRs receiving ethanol, propionate, or both hydrogenic substrates. When a large quantity of propionate was suddenly added to a propionatefed CSTR, P(H(2) ) increased to 10(-4) atm and propionate oxidation remained energetically favorable. When ethanol was added to a CSTR receiving ethanol, P(H(2) ) rose to 6.3 x 10(-3) atm within 5 h. In both perturbations, P(H(2) ) remained at levels such that oxidation of the hydrogenic substrate remained energetically favorable throughout the transient. Sudden increase in ethanol concentration in the ethanol- and propionate-fed CSTR resulted in an increase in P(H(2) ) such that propionate oxidation became energetically unfavorable and was blocked. Propionate utilization resumed when the added ethanol was depleted and P(H(2) ) returned to its previous steady-state levels. Ethanol perturbation of ethanol- and propionate-fed CSTRs led to the formation of reduced products, including n-propanol and four-through seven-carbon n-carboxylic acids, when P(H(2) ) was elevated; these products disappeared after P(H(2) ) returned to previous, steady-state levels. The transformations were consistent with reaction energetics. Reduced product formation may have been a sink for reducing equivalents, as an alternative to oxidation for propionate utilization, as indicated by an electron equivalents balance over the time course of experiments.

  View details for Web of Science ID A1989U763800005

  View details for PubMedID 18588049

• DEGRADATION OF TRICHLOROETHYLENE BY METHANOTROPHIC BACTERIA IN A LABORATORY COLUMN OF SATURATED AQUIFER MATERIAL WATER SCIENCE AND TECHNOLOGY MAYER, K. P., GRBICGALIC, D., Semprini, L., McCarty, P. L. 1988; 20 (11-12): 175-178

  View details for Web of Science ID A1988T894100026

• THERMOCHEMICAL PRETREATMENT OF LIGNOCELLULOSE TO ENHANCE METHANE FERMENTATION .1. MONOSACCHARIDE AND FURFURALS HYDROTHERMAL DECOMPOSITION AND PRODUCT FORMATION RATES BIOTECHNOLOGY AND BIOENGINEERING BAUGH, K. D., McCarty, P. L. 1988; 31 (1): 50-61

  Abstract

  Over a pH range 1-4 and temperatures from 170 to 230 degrees C, the decomposition rates of xylose, galactose, mannose, glucose, 2-furfural, and 5-hydroxymethyl-2-furfural (5-HMF) were pseudo first order. The effect of temperature and pH on the pseudo first-order decomposition rate constants was modeled using the Arrhenius equation and acid-base catalysis, respectively. Decomposition rates of the monosaccharides were minimum at a pH 2-2.5. Above pH 2.5, the monosaccharide decomposition was base catalyzed, with acid catalysis occurring at a pH of less than 2 for glucose. The furfurals were subject to acid catalysis at below ca. pH 3.5. The hydrothermal conversion of glucose to its decomposition products during thermochemical Pretreatment can be modeled as a combination of series and parallel reactions. The formation rates of identified soluble products from glucose decomposition, 5-HMF and levulinic acid, were also functions of temperature and pH. The rate of 5-HMF formation relative to glucose decomposition decreased as the pH increased from 2.0 to 4.0, with levulinic acid formation only detected when the pH was 2.5 or less. For glucose decomposition, humic solids accounted for ca. 20% of the decomposition products.

  View details for Web of Science ID A1988L611800008

  View details for PubMedID 18581563

• THERMOCHEMICAL PRETREATMENT OF LIGNOCELLULOSE TO ENHANCE METHANE FERMENTATION .2. EVALUATION AND APPLICATION OF PRETREATMENT MODEL BIOTECHNOLOGY AND BIOENGINEERING BAUGH, K. D., Levy, J. A., McCarty, P. L. 1988; 31 (1): 62-70

  Abstract

  A model was developed and evaluated as a tool for predicting the formation of soluble products from staged thermochemical treatment of lignocellulosic materials under acidic conditions typical of autohydrolysis. The model was used to predict the general trend of hemi-cellulose and cellulose hydrolysis between pH 2 and 4 and temperatures of 170-230 degrees C, and results were compared with experimental data. When the model was evaluated for this range of temperatures and pH values, results indicated: (1) a relatively low temperature (175 degrees C) during the first stage allows hydrolysis of the hemi-cellulose polysaccharides without significant mono-saccharide decomposition, (2) subsequent stages at higher temperatures (equal or greater than 200 degrees C) are needed for significant cellulose hydrolysis, but glucose decomposition will also occur, and, (3) a pH in the range of 2-2.5 will enhance polysaccharide hydrolysis while limiting monosaccharide decomposition. The model's predictions, indicating that the formation of biodegradable products could be optimized using Pretreatments at pH 2-2.5 for the pH range evaluated, were confirmed in experiments with white fir as a representative lig nocellulose.

  View details for Web of Science ID A1988L611800009

  View details for PubMedID 18581564

• ABIOTIC AND BIOTIC TRANSFORMATIONS OF 1,1,1-TRICHLOROETHANE UNDER METHANOGENIC CONDITIONS ENVIRONMENTAL SCIENCE & TECHNOLOGY Vogel, T. M., McCarty, P. L. 1987; 21 (12): 1208-1213

  View details for Web of Science ID A1987L063200015

• OPERATIONAL EXPERIENCES WITH ACTIVATED CARBON ADSORBERS AT WATER FACTORY 21 JOURNAL OF ENVIRONMENTAL PATHOLOGY TOXICOLOGY AND ONCOLOGY McCarty, P. L., Argo, D., Reinhard, M. 1987; 7 (7-8): 319-338

  View details for Web of Science ID A1987L461800022

  View details for PubMedID 3694480

• TRANSFORMATIONS OF HALOGENATED ALIPHATIC-COMPOUNDS ENVIRONMENTAL SCIENCE & TECHNOLOGY Vogel, T. M., Criddle, C. S., McCarty, P. L. 1987; 21 (8): 722-736

  View details for Web of Science ID A1987J403100004

• ES Critical Reviews: Transformations of halogenated aliphatic compounds. Environmental science & technology Vogel, T. M., Criddle, C. S., McCarty, P. L. 1987; 21 (8): 722-736

  View details for DOI 10.1021/es00162a001

  View details for PubMedID 19995052

• ANAEROBIC WASTE-WATER TREATMENT .4. ENVIRONMENTAL SCIENCE & TECHNOLOGY McCarty, P. L., Smith, D. P. 1986; 20 (12): 1200-1206

  View details for Web of Science ID A1986F016100003

• REMOVING TRACE ORGANICS BY REVERSE-OSMOSIS USING CELLULOSE-ACETATE AND POLYAMIDE MEMBRANES JOURNAL AMERICAN WATER WORKS ASSOCIATION Reinhard, M., Goodman, N. L., McCarty, P. L., ARGO, D. G. 1986; 78 (4): 163-174

  View details for Web of Science ID A1986A742900004

• NUMERICAL-SIMULATION OF MIXED-CULTURE BIOFILM - CLOSURE JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE Kissel, J. C., McCarty, P. L., Street, R. L. 1985; 111 (4): 549-551

  View details for Web of Science ID A1985ANE0300015

• UTILIZATION RATES OF TRACE HALOGENATED ORGANIC-COMPOUNDS IN ACETATE-GROWN BIOFILMS BIOTECHNOLOGY AND BIOENGINEERING Bouwer, E. J., McCarty, P. L. 1985; 27 (11): 1564-1571

  Abstract

  Trace concentrations of chlorinated benzenes and chlorinated aliphatics were biotransformed by acetate-supported biofilms, the former under aerobic conditions and the latter under methanogenic conditions. The rates of transformation of the halogenated organic compounds (secondary substrates) differed from that of acetate, the primary substrate; some were higher, some were lower, and some were similar. Factors affecting the relative rates of utilization in multisubstrate systems are not known.

  View details for Web of Science ID A1985ATH8100006

  View details for PubMedID 18553609

• BIOTRANSFORMATION OF TETRACHLOROETHYLENE TO TRICHLOROETHYLENE, DICHLOROETHYLENE, VINYL-CHLORIDE, AND CARBON-DIOXIDE UNDER METHANOGENIC CONDITIONS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Vogel, T. M., McCarty, P. L. 1985; 49 (5): 1080-1083

  Abstract

  Tetrachloroethylene (PCE) and trichloroethylene (TCE), common industrial solvents, are among the most frequent contaminants found in groundwater supplies. Due to the potential toxicity and carcinogenicity of chlorinated ethylenes, knowledge about their transformation potential is important in evaluating their environmental fate. The results of this study confirm that PCE can be transformed by reductive dehalogenation to TCE, dichloroethylene, and vinyl chloride (VC) under anaerobic conditions. In addition, [14C]PCE was at least partially mineralized to CO2. Mineralization of 24% of the PCE occurred in a continuous-flow fixed-film methanogenic column with a liquid detention time of 4 days. TCE was the major intermediate formed, but traces of dichloroethylene isomers and VC were also found. In other column studies under a different set of methanogenic conditions, nearly quantitative conversion of PCE to VC was found. These studies clearly demonstrate that TCE and VC are major intermediates in PCE biotransformation under anaerobic conditions and suggest that potential exists for the complete mineralization of PCE to CO2 in soil and aquifer systems and in biological treatment processes.

  View details for Web of Science ID A1985AGU0500011

  View details for PubMedID 3923927

• PERFORMANCE-CHARACTERISTICS OF THE ANAEROBIC BAFFLED REACTOR WATER RESEARCH Bachmann, A., BEARD, V. L., McCarty, P. L. 1985; 19 (1): 99-106

  View details for Web of Science ID A1985AAH4600014

• NUMERICAL-SIMULATION OF MIXED-CULTURE BIOFILM JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE Kissel, J. C., McCarty, P. L., Street, R. L. 1984; 110 (2): 393-411

  View details for Web of Science ID A1984SM27000008

• MODELING OF TRACE ORGANICS BIOTRANSFORMATION IN THE SUBSURFACE GROUND WATER Bouwer, E. J., McCarty, P. L. 1984; 22 (4): 433-440

  View details for Web of Science ID A1984SY29300007

• SECONDARY SUBSTRATE UTILIZATION OF METHYLENE-CHLORIDE BY AN ISOLATED STRAIN OF PSEUDOMONAS SP APPLIED AND ENVIRONMENTAL MICROBIOLOGY LAPATPOLASKO, L. T., McCarty, P. L., Zehnder, A. J. 1984; 47 (4): 825-830

  Abstract

  Secondary substrate utilization of methylene chloride was analyzed by using Pseudomonas sp. strain LP. Both batch and continuously fed reactors demonstrated that this strain was capable of simultaneously consuming two substrates at different concentrations: the primary substrate at the higher concentration (milligrams per liter) and the secondary substrate at the lower concentration (micrograms per liter). The rate of methylene chloride utilization at trace concentrations was greater in the presence of the primary substrate, acetate, than without it. However, when the substrate roles were changed, the acetate secondary substrate utilization rate was less when methylene chloride was present. Thus, substrate interactions are important in the kinetics of secondary substrate utilization. Pseudomonas sp. strain LP showed a preference toward degrading methylene chloride over acetate, whether it was the primary or secondary substrate, providing it was below an inhibitory concentration of ca. 10 mg/liter.

  View details for Web of Science ID A1984SL52400040

  View details for PubMedID 6721491

• CHEMICAL INDICATORS AND SURROGATE PARAMETERS IN WATER-TREATMENT JOURNAL AMERICAN WATER WORKS ASSOCIATION McCarty, P. L., AIETA, E. M. 1984; 76 (10): 98-106

  View details for Web of Science ID A1984TT43600013

• THE EFFECT OF THERMAL PRETREATMENT ON THE ANAEROBIC BIODEGRADABILITY AND TOXICITY OF WASTE ACTIVATED-SLUDGE WATER RESEARCH Stuckey, D. C., McCarty, P. L. 1984; 18 (11): 1343-1353

  View details for Web of Science ID A1984TN14500002

• ORGANIC CONTAMINANT BEHAVIOR DURING RAPID INFILTRATION OF SECONDARY WASTEWATER AT THE PHOENIX 23RD AVENUE PROJECT WATER RESEARCH Bouwer, E. J., McCarty, P. L., Bouwer, H., Rice, R. C. 1984; 18 (4): 463-472

  View details for Web of Science ID A1984SJ83200011

• TRANSFORMATIONS OF 1-CARBON AND 2-CARBON HALOGENATED ALIPHATIC ORGANIC-COMPOUNDS UNDER METHANOGENIC CONDITIONS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Bouwer, E. J., McCarty, P. L. 1983; 45 (4): 1286-1294

  Abstract

  Several 1- and 2-carbon halogenated aliphatic organic compounds present at low concentrations (less than 100 micrograms/liter) were degraded under methanogenic conditions in batch bacterial cultures and in a continuous-flow methanogenic fixed-film laboratory-scale column. Greater than 90% degradation was observed within a 2-day detention time under continuous-flow methanogenic conditions with acetate as a primary substrate. Carbon-14 measurements indicated that chloroform, carbon tetrachloride, and 1,2-dichloroethane were almost completely oxidized to carbon dioxide, confirming removal by biooxidation. The initial step in the transformations of tetrachloroethylene and 1,1,2,2-tetrachloroethane to nonchlorinated end products appeared to be reductive dechlorination to trichloroethylene and 1,1,2-trichloroethane, respectively. Transformations of the brominated aliphatic compounds appear to be the result of both biological and chemical processes. The data suggest that transformations of halogenated aliphatic compounds can occur under methanogenic conditions in the environment.

  View details for Web of Science ID A1983QK23700020

  View details for PubMedID 6859849

• TRANSFORMATIONS OF HALOGENATED ORGANIC-COMPOUNDS UNDER DENITRIFICATION CONDITIONS APPLIED AND ENVIRONMENTAL MICROBIOLOGY Bouwer, E. J., McCarty, P. L. 1983; 45 (4): 1295-1299

  Abstract

  Trihalomethanes, carbon tetrachloride, 1,1,1-trichloroethane, 1,2-dibromoethane, chlorinated benzenes, ethylbenzene, and naphthalene at concentrations commonly found in surface and groundwater were incubated under anoxic conditions to study their transformability in the presence of denitrifying bacteria. None of the aromatic compounds showed significant utilization relative to sterile controls at initial concentrations from 41 to 114 micrograms/liter after 11 weeks of incubation. Of the halogenated aliphatic compounds studied, transformations of carbon tetrachloride and brominated trihalomethanes were observed after 8 weeks in batch denitrification cultures. Carbon from the decomposition of carbon tetrachloride was both assimilated into cell material and mineralized to carbon dioxide. How this was possible remains unexplained, since carbon tetrachloride is transformed to CO2 by hydrolysis and not by oxidation-reduction. Chloroform was detected in bacterial cultures with carbon tetrachloride initially present, indicating that reductive dechlorination had occurred in addition to hydrolysis. The data suggest that transformations of certain halogenated aliphatic compounds are likely to occur under denitrification conditions in the environment.

  View details for Web of Science ID A1983QK23700021

  View details for PubMedID 6859850

• Model of steady-state-biofilm kinetics. Biotechnology and bioengineering Rittmann, B. E., McCarty, P. L. 1982; 24 (10): 2291-?

  View details for PubMedID 18546138

• ANAEROBIC DEGRADATION OF HALOGENATED 1-CARBON AND 2-CARBON ORGANIC-COMPOUNDS ENVIRONMENTAL SCIENCE & TECHNOLOGY Bouwer, E. J., Rittmann, B. E., McCarty, P. L. 1982; 16 (2): 130-130

  View details for Web of Science ID A1982MZ52100022

• REMOVAL OF TRACE CHLORINATED ORGANIC-COMPOUNDS BY ACTIVATED CARBON AND FIXED-FILM BACTERIA ENVIRONMENTAL SCIENCE & TECHNOLOGY Bouwer, E. J., McCarty, P. L. 1982; 16 (12): 836-843

  View details for Web of Science ID A1982PS89200011

  View details for PubMedID 22236258

• HEAT-TREATMENT AND ANAEROBIC-DIGESTION OF REFUSE JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Gossett, J. M., Stuckey, D. C., Owen, W. F., McCarty, P. L. 1982; 108 (3): 437-454

  View details for Web of Science ID A1982NS42800001

• ANAEROBIC DEGRADATION OF HALOGENATED 1-CARBON AND 2-CARBON ORGANIC-COMPOUNDS ENVIRONMENTAL SCIENCE & TECHNOLOGY Bouwer, E. J., Rittmann, B. E., McCarty, P. L. 1981; 15 (5): 596-599

  View details for Web of Science ID A1981LN35700025

  View details for PubMedID 22283955

• A COMPARISON OF THE CHARACTERISTICS OF SOLUBLE ORGANIC NITROGEN IN UNTREATED AND ACTIVATED-SLUDGE TREATED WASTEWATERS WATER RESEARCH Parkin, G. F., McCarty, P. L. 1981; 15 (1): 139-149

  View details for Web of Science ID A1981KY04900021

• CHARACTERIZATION AND METHANE FERMENTATION OF SOLUBLE PRODUCTS FROM STAGED AUTOHYDROLYSIS OF WOOD BIOTECHNOLOGY AND BIOENGINEERING BAUGH, K. D., Bachmann, A., Everhart, T., McCarty, P. L. 1981: 113-124

  View details for Web of Science ID A1981NC63200012

• PRODUCTION OF SOLUBLE ORGANIC NITROGEN DURING ACTIVATED-SLUDGE TREATMENT JOURNAL WATER POLLUTION CONTROL FEDERATION Parkin, G. F., McCarty, P. L. 1981; 53 (1): 99-112

  View details for Web of Science ID A1981KZ89800016

• SOURCES OF SOLUBLE ORGANIC NITROGEN IN ACTIVATED-SLUDGE EFFLUENTS JOURNAL WATER POLLUTION CONTROL FEDERATION Parkin, G. F., McCarty, P. L. 1981; 53 (1): 89-98

  View details for Web of Science ID A1981KZ89800015

• SUBSTRATE FLUX INTO BIOFILMS OF ANY THICKNESS JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Rittmann, B. E., McCarty, P. L. 1981; 107 (4): 831-849

  View details for Web of Science ID A1981LZ72900015

• TRACE ORGANICS IN GROUNDWATER ENVIRONMENTAL SCIENCE & TECHNOLOGY McCarty, P. L., Reinhard, M., Rittmann, B. E. 1981; 15 (1): 40-?

  View details for Web of Science ID A1981KW80400007

• ORGANIC CONTAMINANT BEHAVIOR DURING GROUNDWATER RECHARGE JOURNAL WATER POLLUTION CONTROL FEDERATION Roberts, P. V., McCarty, P. L., Reinhard, M., Schreiner, J. 1980; 52 (1): 161-172

  View details for Web of Science ID A1980JD17700019

• ORGANICS IN WATER - AN ENGINEERING CHALLENGE JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE McCarty, P. L. 1980; 106 (1): 1-17

  View details for Web of Science ID A1980JP27700001

• ANAEROBIC TOXICITY EVALUATION BY BATCH AND SEMI-CONTINUOUS ASSAYS JOURNAL WATER POLLUTION CONTROL FEDERATION Stuckey, D. C., Owen, W. F., McCarty, P. L., Parkin, G. F. 1980; 52 (4): 720-729

  View details for Web of Science ID A1980JS10800010

• FEASIBILITY OF A PEAT BIOGASIFICATION PROCESS RESOURCE RECOVERY AND CONSERVATION BUIVID, M. G., Wise, D. L., RADER, A. M., McCarty, P. L., Owen, W. F. 1980; 5 (2): 117-138

  View details for Web of Science ID A1980KB74000001

• UTILIZATION OF DICHLOROMETHANE BY SUSPENDED AND FIXED-FILM BACTERIA APPLIED AND ENVIRONMENTAL MICROBIOLOGY Rittmann, B. E., McCarty, P. L. 1980; 39 (6): 1225-1226

  Abstract

  Dichloromethane (methylene chloride) was biodegraded by and supported growth of suspended and fixed-film bacteria enriched from sewage.

  View details for Web of Science ID A1980JW98100024

  View details for PubMedID 16345585

• TRACE-ORGANICS BIODEGRADATION IN AQUIFER RECHARGE GROUND WATER Rittmann, B. E., McCarty, P. L., Roberts, P. V. 1980; 18 (3): 236-243

  View details for Web of Science ID A1980JQ98800004

• DESIGN OF FIXED-FILM PROCESSES WITH STEADY-STATE-BIOFILM MODEL PROGRESS IN WATER TECHNOLOGY Rittmann, B. E., McCarty, P. L. 1980; 12 (6): 271-281

  View details for Web of Science ID A1980KZ67600018

• EVALUATION OF STEADY-STATE-BIOFILM KINETICS BIOTECHNOLOGY AND BIOENGINEERING Rittmann, B. E., McCarty, P. L. 1980; 22 (11): 2359-2373

  View details for Web of Science ID A1980KR26400010

• MODEL OF STEADY-STATE-BIOFILM KINETICS BIOTECHNOLOGY AND BIOENGINEERING Rittmann, B. E., McCarty, P. L. 1980; 22 (11): 2343-2357

  View details for Web of Science ID A1980KR26400009

• TRACE ORGANICS REMOVAL BY ADVANCED WASTEWATER-TREATMENT JOURNAL WATER POLLUTION CONTROL FEDERATION McCarty, P. L., Reinhard, M. 1980; 52 (7): 1907-1922

  View details for Web of Science ID A1980KB91800006

• TRACE ORGANICS REMOVAL BY ADVANCED WASTE TREATMENT JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Reinhard, M., Dolce, C. J., McCarty, P. L., ARGO, D. G. 1979; 105 (4): 675-693

  View details for Web of Science ID A1979HL80500005

• BIOASSAY FOR MONITORING BIOCHEMICAL METHANE POTENTIAL AND ANAEROBIC TOXICITY WATER RESEARCH Owen, W. F., Stuckey, D. C., Healy, J. B., Young, L. Y., McCarty, P. L. 1979; 13 (6): 485-492

  View details for Web of Science ID A1979GX19100003

• REMOVAL OF SOLUBLE SECONDARY-EFFLUENT ORGANICS JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Randtke, S. J., McCarty, P. L. 1979; 105 (4): 727-743

  View details for Web of Science ID A1979HL80500008

• OPERATIONAL EXPERIENCES WITH ACTIVATED CARBON ADSORBERS AT WATER FACTORY 21 JOURNAL AMERICAN WATER WORKS ASSOCIATION McCarty, P. L., Argo, D., Reinhard, M. 1979; 71 (11): 683-689

  View details for Web of Science ID A1979HX97200013

• INVESTIGATION OF SOLUBLE ORGANIC NITROGEN-COMPOUNDS IN MUNICIPAL SECONDARY EFFLUENT JOURNAL WATER POLLUTION CONTROL FEDERATION Keller, J. V., Leckie, J. O., McCarty, P. L. 1978; 50 (11): 2522-2529

  View details for Web of Science ID A1978FV01600012

• DIRECT INJECTION OF RECLAIMED WATER INTO AN AQUIFER JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Roberts, P. V., McCarty, P. L., ROMAN, W. M. 1978; 104 (5): 933-949

  View details for Web of Science ID A1978FR19700008

• VARIABLE-ORDER MODEL OF BACTERIAL-FILM KINETICS JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Rittmann, B. E., McCarty, P. L. 1978; 104 (5): 889-900

  View details for Web of Science ID A1978FR19700005

• ANAEROBIC DIGESTION OF SLUDGE FROM CHEMICAL TREATMENT JOURNAL WATER POLLUTION CONTROL FEDERATION Gossett, J. M., McCarty, P. L., Wilson, J. C., Evans, D. S. 1978; 50 (3): 533-542

  View details for Web of Science ID A1978EU09900016

• VARIATIONS IN NITROGEN AND ORGANICS IN WASTEWATERS JOURNAL OF THE ENVIRONMENTAL ENGINEERING DIVISION-ASCE Randtke, S. J., McCarty, P. L. 1977; 103 (4): 539-550

  View details for Web of Science ID A1977DP27700002

• VERIFICATION STUDIES OF BIOFILM MODEL FOR BACTERIAL SUBSTRATE UTILIZATION JOURNAL WATER POLLUTION CONTROL FEDERATION Williamson, K., McCarty, P. L. 1976; 48 (2): 281-296

  View details for Web of Science ID A1976BG79600005

• MODEL OF SUBSTRATE UTILIZATION BY BACTERIAL FILMS JOURNAL WATER POLLUTION CONTROL FEDERATION Williamson, K., McCarty, P. L. 1976; 48 (1): 9-24

  View details for Web of Science ID A1976BD79300001

  View details for PubMedID 1255905

• MULTI-PROCESS BIOLOGICAL TREATMENT MODEL JOURNAL WATER POLLUTION CONTROL FEDERATION Christensen, D. R., McCarty, P. L. 1975; 47 (11): 2652-2664

  View details for Web of Science ID A1975AW42100010

  View details for PubMedID 1219142

• RAPID MEASUREMENT OF MONOD HALF-VELOCITY COEFFICIENTS FOR BACTERIAL KINETICS BIOTECHNOLOGY AND BIOENGINEERING Williamson, K. J., McCarty, P. L. 1975; 17 (6): 915-924

  View details for Web of Science ID A1975AG75900008

• FIELD STUDIES OF NITRIFICATION WITH SUBMERGED FILTERS JOURNAL WATER POLLUTION CONTROL FEDERATION MCHARNESS, D. D., Haug, R. T., McCarty, P. L. 1975; 47 (2): 291-309

  View details for Web of Science ID A1975V636800009

• NITRIFICATION WITH SUBMERGED FILTERS JOURNAL WATER POLLUTION CONTROL FEDERATION Haug, R. T., McCarty, P. L. 1972; 44 (11): 2086-?

  View details for Web of Science ID A1972N966900004