• Korean Journal of Microbiology
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• v.33 no.3
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• pp.193-198
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• 1997

Microorganisms capable of producing biosurfactant were isolated from oil-contaminated soils and seawater. Among them, the selected strain SW1 was identified as Pseudomonas sp. by taxonomical characteristic tests, and so tentatively named Pseudomonas sp. SWI. The optimal temperature and initial pH for biosurfactant production were TEX>30^{\circ}C.$ and 7.0, respectively. The optimal medium composilion for the production of biosurfactant by Pseudomonas sp. SW1 were hexadecane of 2.0%, yeast extract of 0.04%, $K_{2}HPO_4$ of 0.02%, $KH_2PO_4$ of 0.03% and $MgSO_4$ center dot $7H_2O$ of 0.04%, respectively. Under the above conditions, minimum wrface tension was 32 mN/m after incubation of 2 days. The biosurfactant was produced during initial stationary phase in the optimal medium. Pseudotnonas sp. SWl utilized various hydrocarbons such as Bunker oils, n-alkanes and branched alkanes as a sole carbon source.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.276-285
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• 2003

To control pythium root rot, Bacillus lentimorbus WJ5a17 with high anti-fungal activity against Pythium ultimum was induced from B. lentimorbus WJ5 by gamma radiation ($^{60}Co$). The biocontrollers of FWJ5 and FWJ5a17 were formulated ($1.0\times 10^{11}$) with B. lentimorbus WJ5 and WJ5a17, respectively, The population density of FWJ5 and FWJ5a17 maintained highly up to $1.0\times 10^{9}$ CFU $g^{-1}$ in nursery and field soils until 30 days after treatment. P. ultimum spores germination were inhibited 71.0% and 81.4% by FWJ5 and FWJ5a17, respectively. Pythium root rot of yea pepper, Chinese cabbage and radish were significantly (p < 0.05) controled by one time treatment of FWJ5 and FWJ5a17.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.170-170
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• 1994

항암제 KR 53170 및 관련 화합물의 항암 효과에 관한 연구의 일환으로 Phellinus linteus 균사배양물로부터 분리한 항암성 단백다당체 (분자량 8000 이상의 고분자 분획) PL-KP률 장내세균의 효소활성을 이용하여 부분분절(partial fragmentation)시킴으로써 항암력 증강 가능성을 검토하였다. 1. 장내세균을 이용한 PL-Kp의 처리 :PL-Kp 5.62g을 기본배지 281m1에 용해 시킨후 그 중 100m1에는 Py-92 균주(endoglucanase 생성균주)를, 다른 100m1에는 초식동물로부터 분리한 활성 균총을 접종한후 배양물 100m1 당 BH1 broth 10n1를 첨가하고 24시간 배양하였다. 배양물을 원심분리하여 그 상등액을 열탕에서 15분간 가열하고 투석, 동결건조하여 건조분말로 획득하였다. 이증 Py-92 균주로 처리한 시료를 Kp-F1, 균총으로 처리한 시료를 Kp-F2, 균을 접종하지 않고 처리한 시료를 Kp-FC라 한다. 2. 분절 (Fragmentation) 확인 : 증류수에 용해시킨 시료의 Sephadex G-25 컬럼을 이용한 gel filtration 유형(컬럼 통과 속도 및 착색대 유형)등을 관찰하여 Kp-F1 및 Kp-F2가 성공적으로 분절되었음을 확인하였다. 3. 분절 Kp의 항암력 실험 : ICR 마우스내 피하에 이식한 sarcoma 180고형암에 대한 항암력을 비교실험하여 부분분절에 의해 항암력이 증가 여부를 확인하였다. 그 결과 PL-Kp가100mg/kg/day ip의 용량에서 49.5%의 종양저지율을 발휘하였으나 균총을 이용하여 부분분절시킨 시료(Kp-F2)는 그 1/5용량에서도 87%의 종양저지율을 발휘하여 항암력이 현저히 증가 되었음을 확인하였다. 한편 Py-92 균주를 이용하여 분절시킨 Kp-F1도 100mg/kg용량에서 76%의 종양저지율을 나타내었다. 이로써 부분분절 조작을 통하여 항암성 단백다당류인 PL-Kp 의 항암력을 현저히 증가시킬 수 있음이 입증되었다.

• Journal of Life Science
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• v.21 no.12
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• pp.1716-1720
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• 2011

A bacterium hydrolysing various organic materials including cellulose, protein, starch and lipid was isolated. The isolate was identified as Bacillus subtilis, and named Bacillus subtilis CK-2 in this paper. This bacterium showed optimal growth at $40\sim45^{\circ}C$, pH 6~9, and 0~3% of NaCl. B. subtilis CK-2 seemed to synthesis highly active autolysin. The hydrolytic enzymes produced by B. subtilis CK-2 were primary enzymes because extracellular enzyme activities varied similarly to the growth curve. The hydrolytic enzymes seemed to be stable at basic pH conditions. From these results, B. subtilis CK-2 was found to bea useful bacterial agent for composting, or for use in feed-production waste in agriculture, fishery, forest materials, livestock farming, and food.

• Journal of the Korea Organic Resources Recycling Association
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• v.1 no.1
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• pp.59-68
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• 1993

Change in microbial numbers during experimental composting has been investigated. The results show that bacteria and actinomycetes play an important role in decomposing the composting material. The number of bacteria has no relation to the efficiency of composting, though it greatly correlates to the decomposition ratio. Bacterial growth activity that shows potential of bacterial growth was originally proposed. The influence of pH and the decomposition ratio on the growth activity has been studied. It was clarified that the bacterial growth activity is useful in evaluating the efficiency of composting and the maturity of produced compost.

• Journal of Life Science
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• v.22 no.2
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• pp.167-176
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• 2012

Three protease-producing halophilic bacteria were isolated from fermenting anchovy. Isolated FAM 10, FAM 114, and FAM 115 were found to grow optimally at salt concentrations of 2-4%, 10%, and 6%, respectively, and could grow in salinity of up to 18-22%. The salinity conditions for optimum protease production were 6% in FAM 10 and 10% in FAM 114 and FAM 115. The protease activity of FAM 10 was gradually inhibited by the addition of NaCl up to 10%, and was not evident at 14%, whereas FAM 114 and FAM 115 displayed protease activity at 14% NaCl and could not be measured at 18%. These results demonstrated that the three isolated strains belong to protease-producing, moderately halophilic bacteria. Strain FAM 10, FAM 114, and FAM 115 were identified as Salinivibrio sp., Halobacillus sp., and Halobacillus sp. respectively, based on comparative analyses of the 16S rRNA gene and the 16S-23S intergenic space sequence (IGS), biochemical testing, and Gram staining. Salinivibrio sp. FAM 10 had two 16S rDNAs containing different sequences at position 191 and four IGSs that harbored no tRNA gene and tRNA genes for isoleucine, alanine, glutamate, lysine, and/or valine. Halobacillus sp. FAM 114 and FAM 115 had completely identical 16S rRNA gene sequences and showed 99% identity to the sequences of various Halobacillus strains. The three IGSs found in the genome of both strains displayed 99% sequence identity with Halobacillus aidingensis and Halobacillus sp. JM-Hb, and had $IGS^0$ with no tRNA gene and $IGS^{IA}$ with tRNA genes for isoleucine and alanine.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.124-132
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• 2017

Microbial secondary metabolites of marine organisms are regarded as major sources of structurally and biologically novel compounds with numerous potential uses. Sponge-microbe associations are among the most interesting sources for exploring bioactive compounds. In this study, the bacterial strain Microbulbifer sp. (127CP7-12) was isolated from the Asian marine sponge Hymeniacidon sinapium collected at an intertidal zone on the west coast of Korea. Cultured bacteria produced a violet pigment, and optimal culture conditions for violet pigment production were investigated. Maximum production of the violet pigment from the strain culture was observed under the conditions of $25^{\circ}C$, pH 6.0, and 3% NaCl. Acetone provided better extraction of the pigment from fermented broth compared with ethanol and methanol. The proposed structure of the major component in the extracted crude pigment was determined via high-performance liquid chromatography, nuclear magnetic resonance, mass spectrometry, and UV spectra analyses, which showed that the metabolite was the promising bioactive compound violacein. This study describes the examination of marine bioactive materials from microbe-engaged metabolites and the ecological implications of the sponge-microbe association in a changing ocean.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1045-1052
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• 2017

In this study, a battery of genetic-toxicity studies on corn silk extract with high maysin content were performed according to internationally accepted protocols. In a mutation test using Salmonella Typhimurium TA1535, TA1537, TA98, and TA100, the number of mutant colonies did not significantly increase up to a maximum concentration of $5,000{\mu}g/plate$ in the presence or absence of the S9 metabolic activation system. In the chromosome aberration test using Chinese hamster lung fibroblasts, negative results were observed in the concentration up to $1,250{\mu}g/mL$ of corn silk extract. In the micronucleus test using ICR mice, incidence of polymorphonuclear erythrocytes with a maximum concentration of 2,000 mg/kg corn silk extract did not show any significant difference compared to the negative control group. Based on these results, the test substance, con silk extract, did not influence genotoxicity.

• Korean journal of food and cookery science
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• v.17 no.6
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• pp.565-570
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• 2001

Soibirhym(Portulace oleracea) was extracted by methanol and its antimicrobial activities against food spoilage or foodborne disease microorganisms were investigated by the paper disc method. The microorganisms used in this experiment included 5 species of bacteria(Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella Pneumoniae, Staphylococcus aureus) and 3 species of fungi(Fusarium solani, Aspergillus flavius, Penicillium citreonigrum). Soibirhym showed high antimicrobial activites against P. citreonigrum, P. aeruginosa and K. pneumoniae. Minimum inhibitory concentrations(MICs) on S. aureus, P. citreonigrum and K. pneumoniae were 200, 200 and 250 mg/㎖, respectively. In the methanol extracts from Soibirhym, 147 kinds of compound were separated by GC/MS. The extraction yields of phenolics, furans, alcohols, acids and esters, ketones, aldehydes, and miscellaneous compounds were 7.43%, 6.13%, 2.20%, 41.06%, 9.21%, 0.15% and 1.08%, respectively. Some antimicrobial compounds such as 2,3-dihydro-benzofuran, 4-hydroxy-3-methoxy-benzoic acid, 4-hydroxy benzeneethanol were detected in the methanol extract.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.298-303
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• 2007

A halophilic bacterium, H. subglaciescola DH-1, grew at 2.0 M salinity, but did not grow at 0.8 M salinity when cultivated at higher temperature ($40^{\circ}C$) than optimum ($30^{\circ}C$). When the cell extract of strain DH-1 was heated at $50^{\circ}C$ for 60 min in the absence of NaCl, isocitrate dehydrogenase and malate dehydrogenase lost their activities, but when it was heated in the presence of 2.0 M NaCl, the activity was maintained. Meanwhile, the cell extract of E. coli did not catalyze the reduction of $NAD^+$ to NADH coupled with the oxidation of isocitrate and malate at higher salinities than 1.0 M. The pH range for DH-1 was 7 to 10, and that for E. coli was 5 to 9. DH-1 was not grown in conditions with sodium salts other than NaCl.