• Journal of Environmental Science International
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• v.2 no.2
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• pp.95-102
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• 1993

In order to find the most fitted biodegradation model, biodegradation models to the initial 4-chlorophenol concentrations were investigated and had been fitted by the linear regression. The degrading bacterium, EL-091S, was selected among phenol-degraders. The strain was identified with Pseudomows sp. from the result of taxonomical studies. The optimal condition for the biodegradation was as fellows: secondary carbon source, concentration of ammonium nitrate, temperature and pH were 200mg/l fructose, 600 mg/l, $30^{\circ}C$ and 7.0 respectively. The highest degradation rate of the 4-chlorophenol was about 58% for 24 hours incubation on the optimal condition. Biodegradation kinetics model of 5 mg/l 4-Chlorophenol, 10 mg/l 4-chlorophenol and 50 mg/l 4-chlorophenol were fitted the zero order kinetics model, respectively. Key Words : 4-chlorophenol, Pseudomonas sp., zero order kinetics model.

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.27-32
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• 1980

We isolated a strain of Pseudomonas sp. from soil to utilize furfuryl alcohol as a carton source by enrichment culture. Alcohol dehydrogenase from this bacteria was purified 700-fold by Sephadex G-200 and affinity column chromatography to be homogeneous by electrophoresis and analytical centrifugation. This enzyme had a molecular weight of 120,000 and was composed of four subunits consisting of 266 amino acid residues. The optimal pH of the enzyme was pH 8.5 to 9, and the optimal temperature was, 45$^{\circ}C$. This enzyme was stable at 55$^{\circ}C$, but lost 80% of its activity in 10min at 6$0^{\circ}C$.

• Korean Journal of Microbiology
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• v.30 no.1
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• pp.8-14
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• 1992

Nucleotide Sequence of phnE Gene Encoding Extradiol Dioxygenase fromPseudomonas sp. Strain DJ77Kim, Young-Chang'.", Myeong-Su Shin1, Kil-Sang Younl, Young-Soon Park1, andUg-Hyeon Kim'.' (Department of Microbiology, C'hungbuk National University.Cheongju 360-763, KOREA. and 'Research Center for Molecular Microbiology,Seoul National University)nal University)

• KSBB Journal
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• v.11 no.2
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• pp.201-210
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• 1996

The production of polyhydroxyalkanoate(PHA) from glucose by batch and fed-batch culture of Pseudomonas sp. HJ was studied. In batch culture using fermentor, 400 rpm of agitalion speed, 2 vvm of aeration rate, 18 hours of inoculum age, and 5% (vlv) of inoculum size were optimal. PHA production was not increased by deficiency of oxygen. In a batch culture, the final call mass was $6.251g/\ell$, and PHA content was 20% of dry cell weight. In a constant feeding fed-batch culture, cell mass increased to $33.24g/\ell$, and PHA content reached 48.9% of dry cell weight. In an intermittent feeding fed-batch culture, cell mass increased to $37.89g/\ell$, and PHA content reached 53.5% of dty cell weight.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.681-684
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• 2001

Pseudomonas sp. F721 isolated from soil produced a substance related in seeds germination inhibition. Addition of phytohormone, and GA (gibberellin acid) in the culture broth elevated production of the germination inhibition substance. The production of the substance was optimized in the culture conditions of $35^{\circ}C$, pH 9.0, 150 rpm, 48 hr, glucose 0.5% (w/v), and innoculation ratio 1.0% (v/v). The physical and chemical stability of the substance in the variety of pH ranging from 2.0 to 12.0 and from freezing to $100^{\circ}C$ were shown. The germination inhibition substance suppressed 90% of germination compared with that of the control experiment in a few days.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.336-342
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• 2013

Trichloroethylene (TCE) is a widely used substance in commercial and industrial applications, yet it must be removed from the contaminated soil and groundwater environment due to its toxic and carcinogenic nature. We investigated bacterial community structure, dominant bacterial strain, and removal efficiency in a TCE contaminated groundwater treatment system using immobilized carrier. The microbial diversity was determined by the nucleotide sequences of 16S rRNA gene library. The major bacterial population of the contaminated groundwater treatment system was belonging to BTEX degradation bacteria. The bacterial community consisted mainly of one genus of Pseudomonas (Pseudomonas putida group). The domination of Pseudomonas putida group may be caused by high concentration of toluene and TCE. Furthermore, we isolated a toluene and TCE degrading bacterium, named Pseudomonas sp. DHC8, from the immobilized carrier in bioreactor which was designed to remove TCE from the contaminated ground water. Based on the results of morphological and physiological characteristics, and 16S rRNA gene sequence analysis, strain DHC8 was identified as a member of Pseudomonas putida group. When TCE (0.83 mg/L) and toluene (60.61 mg/L) were degraded by this strain, removal efficiencies were 72.3% and 100% for 12.5 h, respectively. Toluene removal rate was 2.89 ${\mu}mol/g$-DCW/h and TCE removal rate was 0.02 ${\mu}mol/g$-DCW/h. These findings will be helpful for maintaining maximum TCE removal efficiency of a reactor for bioremediation of TCE.

• KSBB Journal
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• v.8 no.2
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• pp.156-163
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• 1993

Strains degrading ethylene glycol(EG) and terephthalic acid(TPA) were isolated from water systems, and identified as Pseudomonas sp. They were named as Pseudomonas sp. EAW for EG and as Pseudomonas sp. TS2 for TPA. The optimal culture conditions of temperature, pH and nitrogen source were found to be $35^{\circ}C$, 7.5 and ammonium sulfate, respectively. The growth of strains and removal efficiency was slightly promoted by trace elements such as niacin and biotin in case of EG, and by trace elements such as $Na_2MoO_4{\cdot}2H_2O$ and thiamin i case of TPA. With increasing inoculation sloe for batch culture, the removal efficiency of EG by the strain EAW was conspicuously increased, while the removal efficiency of TPA by the strain TS2 was not changed as much as that of EG. The growth rate of the strain EAW was much more decreased than that of the strain TS2 in the enrichment medium, as the frequency of repeated-batch culture in the rich-medium increased. in case of real wastewater, growth rate and removal efficiencies of EG and TPA were lower than those in the enrichment medium. $COD_{Mn}\;and\;COD_{Cr}$ removal efficiencies after 48 hrs batch culture in real wastewater were 89% and 93%, respectively. The specific growth rate was inhibited when the initial concentration of EG or TPA was more than 25g/L.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.200-207
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• 1997

In order to evaluate the soil microbiological characteristics of paddy fields in Korea, surface soils were sampled from 63 sites in different agroclimatic zones before submersion of the fields. The distribution of microorganisms and the microbial diversity indices were examined. Soil microbial populations were generally higher in southern area than in northern area. The colony forming units(cfus) of fluorescence Pseudomonas sp. showed the greatest regional differences, among the microbes investigated. On the topographical differences, the cfus of aerobic bacteria, fluorescence Pseudomonas sp. and Azotobacter sp. maintained high level in coastal plains; and on the sail textural difference, fungus was the highest in clay soil, but Bacillus sp., Azotobacter sp and denitrifiers were the highest in silty clay loam soil at 0.05 probability level based on the multiple range test. The numbers of ammonium oxidizers and Azotobacter sp. were increased with soil pH. Microbial diversity indices of paddy fields which calculated from the percentages of Bacillus sp. fluorescence Pseudomonas sp. Azotobacter sp. denitrifiers, ammonium oxidizers, nitrite oxidizers, actinomycetes and fungus to these total microbial numbers were between 0.109 and 0.661. On the soil textures, the microbial diversity indices of sandy, sandy loam, silty clay loam, clay loam and clay soil were 0.443, 0.427, 0.414, 0.405 and 0.362 respectively.

• The Korean Journal of Food And Nutrition
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• v.8 no.4
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• pp.275-279
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• 1995

A bacterium L-10 which produce mush of glutamic acid was Isolated from soil and identified as the genus Pserdomonas. The maximal glutamic acid production was obtained when the strain was cultured at 3$0^{\circ}C$ for 30 hrs in the optimal medium containing 5% glucose, 0.5% each of urea and yeast extract, 0.1% K2HP04, 0.02% MgSO4.7H20, 0.3% (NH, )rHP04, 0.5ug/l biotin and Initial pH 7.0, and then final glutamic acid production under the above conditions was 1.2mg/ml of cell cultures.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.82-87
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• 1991

Xanthomonns curnpestris M12, Xunthornonas sp. M28, Acinetuhucter Iwofz GI, and Klebsiella pneumoniae L25, Pseudomonas rnaltophiliu N246 were screened to increase the ability for crude oil utilization. All of these could utilize hexadecane and octane with the exception of N246 strain for only octane biodegradation. Thus N246, M12, and M28, strains were specially examined for octane oxidation. Octane biodegradation by three strains showed the optimal conditions at $30^{\circ}C$, pH 7.0~9.0, and 0.2~0.3% octane concentration as a substrate. It was found that P. multofihila N246 and X. curnpestns M12 had plasmid and the cured plasmid from N246 strain lost octane uitilization. Therefore, it was confirmed that certain genes for octane utilization were Iocated on OCT plasmid in N246 strain. The size of OCT plasmid in N246 strain was 118 kb. The N246 strain was resistant to ampicillin.