• Food Science and Biotechnology
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• 제18권4호
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• pp.1030-1034
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• 2009

A fermenting microorganism involved in formation of ortho-dihydroxyisoflavones (ODIs) during aging of doenjang (Korean fermented soybean paste) has been investigated. Microorganisms in ODI-containing doenjang were isolated by cultivating on yeast mold (YM) agar medium containing 0-7% NaCl. ODI formation of the isolated strains was examined by gas chromatography/mass spectrometry (GC/MS) analysis after cultivation in modified YM broth or soybean extract medium. An ODI-producing microbe was identified as Bacillus subtilis HS-1 based on 16S rRNA gene sequence analysis. The strain has produced 8-hydroxydaidzein as a major product during growth in the modified YM broth or soybean extract medium. Therefore, it was concluded that one of the microorganisms involved in the formation of ODIs in doenjang was B. subtilis HS-1.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.687-694
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• 1995

Alkalophilic Bacillus sp. HJ-12 producing $\beta $-1, 4-D-arabinogalactanase was isolated from soil in the alkalic condition, pH 10.0. $\beta $-1, 4-D-arabinogalactanase was maximaly produced in the medium consisting of 2% soybean arabinogalactan (SAG), 0.5% yeast extract, 0.5% polypeptone, 0.5% NaCl, 0.1% K$_{2}$HPO$_{4}$, 0.02% MgSO$_{4}$$\cdot $7H$_{2}$O, 0.1% Na$_{2}$CO$_{3}$ under the aerobic condition (pH 8.2). $\beta $-1, 4-D-arabinogalactanase is inducible enzyme so that its activity has been increased 10 fold in the SAG medium than in the glucose medium. Through the ammonium sulfate precipitation, DEAE- Sephadex A-50 ion chromatography, and Sephadex G-75 gel chromatography procedures, this enzyme was purified with a single protein of 11% vield and 110 fold's purity. $\beta $-1, 4-D-arabinogalactanase is endo type enzyme producing ollgosaccharide from SAG.

• 미생물학회지
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• 제30권6호
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• pp.514-518
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• 1992

The present study has been perromed to investigate the optimal conditions for protoplast formation and regeneration of oleandomycin-producing Streptomyces antibioticus (S. antibioticus) KCTC 1081. Mycelia were grown in YME medium containing 0.2% (w/v) glycine and converted into the protoplast by incubating at 35.deg.C for 60 minutes in protoplast buffer (P buffer) containing 4 mg/ml lysozyme. The reversion of protoplasts to the normal filamentous state was examined by the growth on various synthetic agar media. A high reversion rate was obtained by incubating the protoplasts on a hypertonic agar medium containing 20 mM $Mg^{++}$, 5 mM $Ca^{++}$ and 0.3 M sucrose at 28.deg.C for 5 days. From these experiments, we established the improved regeneration medium and a protocol which supports higher and more consistent levels of regeneration of S. antibioticus protoplasts. The regenerant showed an increased antimicrobial activity compared with that of the initial strain.n.n.

• KSBB Journal
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• 제13권2호
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• pp.119-124
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• 1998

Twelve bacterial strains capable of growing on phenol minimal medium were isolated from iron foundry activated sludge by enrichment culture, and amount them, one isolate which was the best in cell growth and phenol degradation was selected and identified as Acinetobacter junii POH. The optimal temperature, initial pH and phenol concentration in the above medium were 3$0^{\circ}C$, 7.5 and 1000 ppm, respectively. Cell growth of Acinetobacter junii POH dramatically increased 20 hrs cultivation-time and reached a almost stationary phsae 40 hrs cultivation-time then phenol was degraded about 98%. Cell growth was inhibited y phenol at concentrations over 1500 ppm. The isolate was resistant to several antibiotics as well as various heavy metal ions. The growth-limiting log P value of Acinetobacter junii POH on organic solvents was 2.9 in the LB medium. Therefore, it is suggested that Acinetobacter junii POH could be effectively used for the biological treatment of wastewater containing the presence of heavy metal ions and organic solvents.

• 미생물학회지
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• 제28권3호
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• pp.274-277
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• 1990

새로운 고체배지 응고제인 Pluronic Polyol F127을 한천대신 사용하여 C. congregatus를 배양하였고 균사 끝(hyphaltip)에 있는 phenoloxidase들의 세포내에서의 존재위치를 확인하였다. 고체배지의 균사에서 원형질체를 얻었고 concanavalin A를 처리하여 세포막을 분리하였다. 세포막 분획에 phenoloxidase들이 존재하였고 이는 이 효소가 light receptor complex의 한 부분임을 시사한다.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.439-444
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• 1996

A bacterial strain, designated as WY22, producing extracellular chitinase was isolated from the soil around the Youngduck area, after enrichment culture in a medium containing $1{\%}$ (w/v) wet colloidal chitin as a sole carbon source. The isolate was identified as a strain of Bacillus sp. based on its morphological and physiological characteristics. It was observed that Bacillus sp. WY22 could inhibit the growth of Fusarium oxysporum with hyphal extention-inhibition assay on potato dextrose agar plate supplemented with $1{\%}$ collidal chitin. Optimum culture conditions of Bacillus sp. WY22 were examined for chitinase production in a chitin medium. High level production of chitinase was observed not only in the chitin medium but in a medium supplemented with $1{\%}$ N-glucosamine or lactose instead of chitin. The optimum concentrations of colloidal chitin and yeast extract were 3.0 and $0.5{\%}$, and the optimum culture conditions for initial pH of medium and temperature were 7.0 and $30^{\circ}C$, respectively, for the production of chitinase.

• 한국식품과학회지
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• 제26권3호
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• pp.295-299
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• 1994

Bacteroides는 대장의 상재균총 중 가장 많이 존재하는 균이다. 본 연구에서는 Bacteroides를 분리하여 동정하고 이들 균주들에 대하여 BL배지와 EG배지를 기본 배지로 하여 항생제 및 대사저해제에 대한 감수성 조사를 한 결과 vancomycin은 Bacteroides와 대장균 이외의 장내균들의 생육을 저해하는 것으로 나타났다. 성인에서 대장균은 Bacteroides에 비하여 숫적으로 훨씬 적게 존재하기 때문에 vancomycin이 첨가된 VA배지를 선택배지로 조제하여 한국인을 대상으로 기존의 NBGT 선택배지와 비교한 결과 선택성이 거의 동일한 것으로 나타났고 유아의 경우에는 VA배지가 NBGT보다 우수하였다.

• Mycobiology
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• 제28권1호
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• pp.33-38
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• 2000

Mycelium of Hericium erinaceum isolate KU-1 was cultured in liquid medium (HL medium) and solid medium (Ko medium) at pH 4.0 in $28^{\circ}C$. 1.0% glucose or fructose was the most favorable carbon source, and 0.2% amonium acetate or $NaNO_3$ was an exellent nitrogen source for mycelial growth as well as production of antimicrobial substances. The mixture of saw dust 70% with rice bran 30% (SR medium) was the substrate for formation of sporophores. The active substrates in extracts from mycelium, culture filtrate and fruiting body were separated by TLC. The solvent for TLC was EtOAc: Chloroform: MeOH (10 : 5 : 10). Phenol-like substances appeared at Rf $0.5{\sim}0.9$, and fatty acid-like substances appeared at Rf $0.1{\sim}0.2$. The purified materials from the extracts showed antimicrobial effects to Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger, Candida albicans and Microsporum gypseum. The S. aureus was the most inhibited. Minimal inhibitory concentration (MIC) of purified white powder and the Hercenone derivatives against S. aureus were $5.65\;{\mu}g/ml$ and $1.85\;{\mu}g/ml$, respectively.

• 한국동물위생학회지
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• 제20권2호
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• pp.205-215
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• 1997

In this study, homogenized mixture of tubercle and pulmonary lymph node showed up tuberculin(PPD) positive dairy cattle was inoculated in experimental animal, and was cultured on medium(Lowenstein Jensen medium, 3% Ogawa). The results obtained through the survey were sumerized as follows ; 1. In experimental animal, goat and rabbits were decreased body weight(25∼28%) and died in 90 days with severe pathogenicity. Rats are slight pathogenicity. 2. Goat, rabbits and rats showed up severe lesions In lung, rabbits was also lesions other organs (kidney, appendix, ileocecum, and I lymph node). 3. Mycobacterium was grown between 5 weeks and 8 weeks on Lowenstein Jensen medium and 3% Ogawa medium. 4. Biochemical test of Mycobacterium cultured on medium was that niacin, nitrate reduction, tween 80 hydrolysis and catalase test were negative, but that urease test was positive. Therefore it was Mycobacterium bovis (M. bovis).

• 한국미생물·생명공학회지
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• 제48권2호
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• pp.167-178
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• 2020

Lipase-producing fungi have been isolated from environments containing lipids. The non-dairy creamer industrial waste has a high amount of lipids so it is a potential source for the isolation of lipase-producing fungi. However, the study of fungi that secrete lipase from this industrial waste has not been reported. The purpose of this study was to obtain lipase-producing filamentous fungi from non-dairy creamer industrial waste. Mineral salt and potato dextrose agar were used as media for the isolation process. The qualitative screening was conducted using phenol red agar medium and the quantitative screening using broth medium containing glucose and olive oil. Isolates producing the highest amounts of lipase were identified with molecular methods. We found that 5 out of 19 isolated filamentous fungi are lipase producers. Further analysis showed that isolate Ms.11 produced the highest amount of lipase compared to others. Based on ITS sequence Ms.11 was identified as Aspergillus aculeatus. The lipase activity in medium containing 1% glucose + 1% olive oil at pH 7.0 and 30℃ after 96 and 120 h of incubation was 5.13 ± 0.30 U/ml and 5.22 ± 0.59 U/ml, respectively. The optimum lipase activity was found at pH 7.0, 30℃ and using methanol or ethanol in the reaction tube. Lipase was more stable at 20-30℃ and maintained 85% of its activity. It was concluded that isolate Ms.11 is a potential source of lipase that catalyzes transesterification reactions. Further studies are required to optimize lipase production to make the strain suitable for industry purposes.