• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.301-301
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• 2005

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.333-337
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• 2000

An oil-degrading yeast, Yarrowia lipolytica 180, exhibits interesting cell surface characteristics under the growth on hydrocarbons. An electron microscopic study revealed that the cells grown on crude oil showed protrusions on the cell surface, and thicker periplasmic space and cell wall than the cell surface, and thicker periplasmic space and cell wall than the cells grown on glucose. Y. lipolytica cells lost its cell hydrophobicity after pronase(0.1 mg/ml) treatment. The strain produced two types of emulsifying materials during the growth on hydrocarbons; one was water-soluble extracellular materials and the other was cell wall-associated materials. Both emulsifying materials at lower concentration (0.12%) enhanced the oil-degrading activity of Moraxella sp. K12-7, which had medium emulsifying activity and negative cell hydrophobicity; however, it inhibited the oil-degrading activity of Pseudomunas sp. K12-5, which had medium emulsifying activity and cell hydrophobicity. These results suggest that the oil-degrading activity of Y. lipolytica 180 is closely associated with cell surface structure, and that a finely controlled application of Y.lipolytica 180 in combination with other oil-degrading microorganisms showed a possible enhancing efficiency of oil degradation.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.31-37
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• 1994

For a microbiological study of composting process, screening and assay method for biopolymer degrading enzymes and microorganisms were developed and for the study of the possibility of composting in anaerobic state, distribution of sulfate reducing bacteria which plays a final role in anaerobic degradation was investigated. Substrates used for the development of assay methods for biopolymer degradation are ${\beta}-glucan$, xylan, dextran, CMC(carboxy methly cellulose), casein, and collagen. These substrates were made insoluble by a cross-linking agent and linked with dye to make chromogenic substrates. ${\beta}-glucan$ and xylan substrates could substitute congo-red method for screening of polymer degrading microorganisms without damaging the colonies. Sulfate reducing bacteria contained in the sample sludge showed preference to lactic acid, propionic acid, butyric acid and formic acid and could use acetic acid and valeric acid.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.112-117
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• 2000

Food waste is the main source of decay, odors and leachate in collection, transportation and landfill due to the high volatile solids (VS) and moisture content. Acidogenic fermentation of food waste is affected by the fermentation constraints including the biodegradability of substrate and the degrading capability of microorganisms. The biodegradability of food waste is mainly related to cellulosic materials, which are hardly degraded and comprise about 50% of food waste. The efficient and economical method of improving hydrolysis is, therefore, to apply microorganisms with increased cellulose-degrading capability. In this experiment, rumen microorganisms were inoculated to improve the low efficiency of acidogenic fermentation, and then compared with that of mesophilic acidogens. The fermentation of food waste in a leaching bed reactor employing rumen microorganisms resulted in the enhanced acidification (71.2% at $3.0d^{-1}$), which was higher than that (59.8% at $4.5d^{-1}$) employing mesophilic acidogens. This indicated that Rumen microorganisms had an enhanced waste-degrading capability.

• Journal of Life Science
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• v.12 no.2
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• pp.129-135
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• 2002

Several kinds of thermophilic, aerobic microorganisms (Bacillus genus), metal leaching microorganisms (Thiobacillus, T. ferooxidans), and other nondegradable chemical-degrading microorganisms (Pseudomonas genus) were utilized to study the effect on composting livestock manure. Under the Carbon-Nitrogen ratio (C/N) of 35∼40 and water content of 50∼65% conditions, the composting in the cycling drum reactor showed slower composting and lower temperature increase than that of the manual reactor. Element analysis after composting indicated relatively high levels of mineral contents with the substitutional effect of chemical fertilizer. Metal analysis before and after composting showed lower As in all, Cr in pig, Pb in cow, Hg in chicken, and Cu in cow manure compost than the regulation values. Compost maturity was ascertained by the several maturity tests. Salmonella and E. cozi detection test by SS or EMB agar plate confirmed the safety from the pathogenic microorganisms. The results suggest that the inoculation of metal and some other chemical degrading microorganisms during composting might decrease metal contamination and increase composting rate.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.279-285
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• 1998

Fenitrothion-degrading microorganisms were isolated from 124 sampling sites of paddy, upland, forest and polluted soil, and wastewater. A total of 1,071 strains were isolated from each selective medium supplemented with 50mg/l of fenitrothion - nutrient agar (NA) 601, potato dextrose agar (PDA) 201, Actinomycetes isolation agar (AIA) 168 and basal salt medium (BSM) 101, respectively. Twenty-eight effective strains of them, which showed more than 80% degradation of fenitrothion by the gasliquid chromatography(GLC) analysis. were successfully selected from each liquid culture supplemented with 50mg/l of fenitrothion - NB 12(upland soil 3, paddy soil 3, forest soil 2, polluted soil 4), PDB 8(upland soil 1, paddy soil 2, forest soil 2, polluted soil 3) and PSB 8(upland soil 1, forest soil 1, polluted soil 6), respectively. Four strains - NPal, NFol, PFol and BPol, which have the most powerful degradation activity were finally selected among 28 fenitrothion-degrading microorganisms based on the degradation rate at the concentration of 100mg/l fenitrothion in enrichment media.

• Textile Coloration and Finishing
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• v.19 no.1 s.92
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• pp.31-36
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• 2007

There are several factors in the degradation of textiles. The crucial factors in textile weakening are humidity, dust, smoke, sunlight, microorganisms and so on. Especially silk fabrics are more susceptible to microorganisms than other fabrics, because they are mainly consisted of proteins. In this study, we investigated the activities for degrading casein and silk fibers with 2 strains, Bacillus cereus TX1 and Pseudomonas fluorescens TX 2, isolated from domestic museums. They were compared to those of standard control strains, Klebsiella pneumoniae and Staphylococcus aureus, usually used for the antibiotic test of fabrics. The caseinolytic activities of K. pneumoniae and S. aureus were higher than those of isolated strains. But in the cases of silk fiber degrading, B. cereus TX 1 showed the highest activity on both silk 1 and silk 2. Therefore, caseinolytic activities were not coincident with the activity to degrade silk fibers. All strains degraded silk 1(strength retention 100%) better than silk 2(strength retention 50%). It means that bacteria mainly participate in the early stage of degrading silk fabrics, but as time goes by, the importance of bacteria for degrading silk fabrics would decreased. Even though the importance of bacteria may decrease, controlling bacterial activity is necessary to preserve historic silk fabrics.

• Journal of Life Science
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• v.11 no.1
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• pp.76-82
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• 2001

Fifteen species of microorganisms were isolate form the intestines of fishes, fish feed, and ferment. Eleven microorganisms except HY4, HY8, HY12, and HY13 were Gram-positive, and HY1, HY2, HY3, HY5, HY6, and HY7 produced lactic acid. The species of HY1, HY2, HY3, HY4, HY5, HY6, HY13, and HY14 showed some growth in the medium containing 1% of NaCl. Except HY6, HY7, HY8, HY12 and HY5, 10 isolates had proteolytic activity, whereas only HY13 and HY14 had lipase activity. From all the results four isolates (HY3, HY4, HY13 and HY14) were chosen for the degradation of fish wastes. There was no mutual inhibition among the microorganisms, and the optimum temperature and pH for the growth of the mixed culture were found to be 3 2$\^{C}$ and 7, respectively. Under the optimum growth conditions the maximum optical density and the maximum specific growth rate were estimated to be 2.35 and {TEX}$0.46h^{-1}${/TEX}, respectively. Major microorganisms in the mixed culture at the log-phase were HY3 and HY4, which occupied 70%. The degrading efficiency of fish waste by the mixed microorganisms was 2.3 times higher, compared to control. The total amount of free amino acids in the degraded products from fish wastes was 39g/100g protein and little odor was produced by the mixed microorganisms after 48 hours.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.540-542
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• 1998

Five microorganisms capable of degrading an aromatic medium-chain-length polyhydroxyalkanoate ($PHA_{MCL}$), poly(3-hydroxy-5-phenylvalerate) (PHPV), were isolated from wastewater-treatment sludge. Among the isolates, JS02 showed degrading activity consistantly during several transfers. The isolate JS02 could hydrolyze another aromatic MCL copolyester, poly(3-hydroxy-5-phenoxyvalerate-co-3-hydroxy-7-phenoxyheptanoate), ［P(5POHV-co-7POHH)］, and other short-chain-length PHAs ($PHA_{SCL}) such as poly(3-hydroxybutyrate) ［P3(HB)］, poly(3-hydroxybutyrate-co-4-hydroxybutyrate) ［P(3 HB-co-4 HB)］, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) ［P(3HB-co-3HV)］ with relatively low activity. The culture supernatant of JS02 showed hydrolyzing activity for the p-nitrophenyl esters of fatty acids.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.22-25
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• 2002

The effect of in-situ chemical oxidation on the indigenous soil microorganisms (total microbes and PAH-degrading microbes) and contaminant removal were investigated. Field soil contaminated with diesel in gas station was collected and the soil was treated from 0 to 900 minutes by in-situ ozonation as chemical remediation. The treated soil samples were incubated with supplying oxygen during the 9 weeks to understand the characteristics of microbes regrowth, damaged by ozone. The sharp decrease of aromatic fraction and TPH was observed within 60 minutes of ozone application and aromatic fraction and TPH then slowly decreased. The phenanthren-degrading bacteria were the most sensitive to ozonation, because 1 hour of ozonation reduced the microbes from 10$^{6}$ CFU/g-soil to below detection limits.