• 한국미생물·생명공학회지
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• 제37권1호
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• pp.55-61
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• 2009

인삼 근권에 존재하는 토양 미생물중 esculin agar법을 이용하여 $\beta$-glucosidase를 생산하는 균주를 분리하고, 다시 ginsenoside $Rb_1$을 선택적으로 분해하는 균주 Gsoil 235를 선발 및 동정하였다. 16S rRNA 염기서열을 sequencing한 후, genebank에서 가장 가까운 type strain을 결정하여 유연 관계를 분석한 결과 Cellulosimicrobium 속의 funkei ATCC BAA-$886^T$(AY501364)와 99.7% 일치하는 균주임을 확인하였다. TSB, LB, NB등 3종류의 배지에서 균의 생장은 접종 후 12-24 시간에서 가장 잘 자라며, TSB>LB>NB의 순으로 잘 자라는 것을 알 수 있었다. ginsenoside $Rb_1$과 8, 24, 48시간 동안 반응시킨 후 TLC로 분석한 결과 NB>LB>TSB순으로 $Rb_1$ 분해 활성이 뛰어나 배지의 생장과 대조적인 결과를 얻었다. 반응시간이 증가할수록 Rd를 포함한 minor ginsenoside의 생성이 증가하였으며, 특히 다른 배지에 비해 균주 생장속도가 상대적으로 낮은 NB는 48시간 후 $Rb_1$을 거의 분해하여 강한 효소 활성을 확인할 수 있었다.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.105-111
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• 1999

In order to produce functional chitin oligosaccharides, a chitinolytic bacterium was newly screened from the viscera of Korean bony fishes, and identified as Bacillus sp. LJ-25. For the production of chitinolytic enzymes, $1.0\%$ nutrient broth and $0.3\%$ colloidal chitin were used as nitrogen and carbon source, respectively. The optimal temperature, initial pH and concentration of NaCl for the enzyme production by Bacillus sp. LJ-25 were $30^{\circ}C$ 6.5-7.0 and $1.0\%$, respectively. The enzyme activity of Bacillus sp. LJ-25 increased until the incubation time of 168 hr, followed by a decrease in activity.

• 한국식품영양과학회지
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• 제23권6호
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• pp.994-1000
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• 1994

Hot water extract from mugwort (Artemisia asiatica nakai) leaves and tea inhibited the growth of Bacillus subtilis by adding to the nutrient broth 1.0% and 0.5% concentration, respectively. Among the important compounds that contributing mugwort like flavor to the mugwort leaves and tea were considered, authenic compound of thujone, caryophyllene and farnesol showed bactericidal effect for Escherichia coli, Enterobacter aerogenes, Vibrio paraheaemolyticus, Psudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus when teste by paper disc method ( 8 mm diameter). The mixture of caryophyllene and farnesol was more bactericidal effect for various bacteria than the mixture of thujone, caryophyllene and farnesol was more bactericidal effect for various bacteria that the mixture of thujone, caryophyllene and farnesol or each compounds . Especially, the mixture of caryophyllene and farnesol showed strong bactericidal effect (diameter of inhibition zone>40mm) for Vibrio parahaemolyticus , Enterobacter aerogenes and BAcillus subtilis.

• 한국미생물·생명공학회지
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• 제24권6호
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• pp.652-656
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• 1996

The 80 strains which produce carrageenan degrading enzyme were isolated from soils, mud, seaweed, marine moluscus and echonodermata samples. Among them, one isolated strain, which showed the highest activity to produce carrageenan degrading enzyme, was used for this study. The isolated strain was identified as Pseudomonas alcaligenes through its morphological, biochemical, and physiological characteristics. The best conditions for enzyme production were 0.7% nutrient broth and 0.2% carrageenan as nitrogen and carbon source, respectively. The optimal pH, NaCl, temperature and culture time for carrageenan degrading enzyme were 7.0, 1.5%, 30* and 96hrs, respectively.

• Journal of Microbiology and Biotechnology
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• 제7권3호
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• pp.200-203
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• 1997

Bacteria isolated from ultrapure water made by a high-purity water manufacturing system in a semiconductor manufacturing plant were classified into two groups which either grew in diluted nutrient broth medium (oligotrophic bacteria) or could not grow (copiotrophic bacteria). The nutritional flexibility of oligotrophic and copiotrophic bacteria was investigated. The oligotrophic bacteria were shown to be able to utilize a significantly broader range of organic substrates than the copiotrophic bateria. This finding substantiates the hypothesis that nutritional flexibility is adaptive for oligotrophic bacteria.

• The Plant Pathology Journal
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• 제15권6호
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• pp.319-322
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• 1999

In order to obtain bacterial metabolites inducing disease resistance in pepper plant, two hundred bacterial isolates were isolated from the rhizosphere soil of tobacco, cucumber, and pepper plant. Ethyl acetate extract of each bacterial culture was used to screening for induction of resistance against phytophthora blight of pepper plant. Application of ethyl acetate extract of an isolate SH122 culture to pepper plant conferred resistance against phytophthora blight consistently and significantly. According to cellular fatty acid analysis and other characteristics, the SH122 culture were significantly lower than those on control plants treated with ethyl acetate extract of nutrient broth. The B. pumilus SH122 itself of ethyl acetate extract of its culture did not show antifungal activity against phytophthora blight in pepper plants.

• 미생물학회지
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• 제11권2호
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• pp.79-88
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• 1973

In order to investigate the effect of gamma radiation on Salmonella typhi, Ty2, the components of amino acids, proteins, carbohydrates and lipids in irradiated cells were compared with those in unirradiated control cells respectively. The results obtained were as follows ; 1) The inactivation curves of Salmonella typhi with $Co^{60}$ .gamma.-ray irradiation were exponential over a wide range to the irradiated doses. 2) Dose for the inactivation factor of $10^8$ was 94.0 Krad in physiological saline or in phosphate buffered saline, 104.2 Krad in nutrient broth, 220.4Krad in frozen state, 552.0 Krad in dried state, 88.3 Krad in the abundance of oxygen and 188.0 Krad in the deficience of oxygen, respectively. 3) Five consecutive irradiation of Salmonella typhi suspension at the dose of 90 Krad gave no additional increase in resistance. 4) Even at the smallest dose of 500 Krad, compositions of amino acids, proteins, carbohydrates, and lipids were more or less decreased and the distinct banding patterns were also lost possibly due to degradation of the protein molecules.

• 미생물학회지
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• 제29권3호
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• pp.167-171
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• 1991

An intracellular protease from cells of Pseudomonas carboxydohydrogena grown on nutrient broth was purified to better than 95% homogeneity in five steps using azocaseine as a substrate. The molecular weight of the native enzyme was determined to be 125, 000. Sodium dodecyl sulfate-gel electrophoresis revealedat least two non-identical subunits of molecular weight 70, 000 and 56, 000. The enzyme activity was completely ingibited by phenylmethylsulfonyl fluoride and diisopropyl fluorophosphate. The enzyme was also inhibited by $Mg^{2+}$ , $Zn^{2+}$ , $Cd^{2+}$, $Cu^{2+}$ , and $Fe^{2+}$ , but was stimulated by iodoacetamide. Maximal reaction rate of the enzyme was observed at pH8.0 and 30.deg.C. The isoelectric point of the enzyme was found to be 7.5. The enzyme was unable to hydrolyze carbon monoxide dehydrogenase.

• 한국환경농학회지
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• 제26권4호
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• pp.332-336
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• 2007

Pseudomonas stutzeri strain KCCM 34719 was used in this experiment to determine the effects of increasing Pb(II) concentrations on its growth rate. To obtain optimum growth conditions, strain KCCM 34719 was cultivated in nutrient broth under various conditions, such as temperature, pH, and NaCl concentration. Optimal conditions for cell growth were $30^{\circ}C$ of temperature, 8.0 of pH, and 3% of NaCl concentration, respectively. Growth response of bacterial cell to Pb(II) showed tolerance to concentrations ranging from 10 to 100 mg ${\ell}^{-1}$ in liquid culture, following a growth pattern similar to the control. Growth rate was greatly inhibited at 200 mg ${\ell}^{-1}$ of Pb(II).

• Food Science and Biotechnology
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• 제14권1호
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• pp.46-48
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• 2005

Growth inhibitory effects of ethanol extracts of green tea and pine needles on Bacillus stearothermophilus isolated from spoiled red bean paste were detected at concentrations higher than 750 ppm, and antimicrobial activity of pine needle extract was slightly higher than that of green tea exract. Growth inhibitory effect of pine needle extract in nutrient broth adjusted to pH 6.0, water-activity 0.92, and $45\;^{\circ}$Brix was observed at 500 ppm. These results indicated growth of B. stearothermophilus could be inhibited by adding pine needle and green tea extracts.