• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 추계 학술대회
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• pp.125-139
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• 2000

The differential enhanced degradation of cis- and trans-1,3-D was observed in the previous two studies performed by Ou et al. (1995) and especially Chung et al. (1999). This study was initiated to investigate the involvement of microorganisms in the differential enhanced degradation of the chemicals. As expected, microorganisms were responsible for the enhanced degradation of the chemicals. A mixed bacterial culture capable of degrading 1,3-D was isolated from an enhanced soil sample collected from a site treated with 1,3-D. Similar to the enhanced soil, the mixed culture degraded trans-1,3-D faster than cis-1,3-D. This mixed culture could not utilize cis- and trans-1,3-D as a sole source of carbon for growth. Rather, a variety of second substrates were evaluated to stimulate the differential enhanced degradation of the two isomers. As a result, the mixed culture degraded cis- and trans-1,3-D only in the presence of a suitable second substrate. Second substrates that had the capacity to stimulate the degradation included soil leachate, tryptone, tryptophan, and alanine. Other substrates tested, including soil extract, glucose, yeast extract, and indole (ailed to stimulate the degradation of the two isomers. Therefore, it appeared that the degradation of cis- and trans-1,3-D was a cometabolic process. The mixed culture was composed of four morphologically distinctive bacterial colonies.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.92-98
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• 1994

The bacteria which secrete surface-active agent and decrease the surface tension of culture broth were isolated from soil samples. Among them, biosurfactant producing strain KK-7 was selected and emulsification was also detected. The KK-7 produced biosurfactant not only lipid but also glucose by using carbon source. Taxonomical characterization tests have demostrated the strain KK-7 to be Pseudomonas aeruginosa. The media composition of the P. aeruginosa KK-7 for the biosurfactant production was 1% glucose, 0.5% tryptone, 0.2% yeast extract, 0.15% potas sium phosphate mono-dibasic, 0.05% MgSO$_{4}$, initial pH 8.5, at 30$\circ $C for 2 days. In this condition, the concentration of biosurfactant was reached CMC 5 in the culture broth. Surface active material was produced maximum at stationary8 phase, but emulsification power was higher at log phase than stationary phase. It was considered that P. aeruginosa KK-7 produced biosurfactant more than one type having defferent properties and each maximum production time was different. The minimun surface tension of biosurfactant in 50 mM Tris buffer (pH8.0) was 28 dyn/cm, and CMC was 1 g/L.

• Journal of Microbiology and Biotechnology
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• 제17권7호
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• pp.1147-1151
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• 2007

Biodegradation of endocrine-disrupting bisphenol A was investigated with several white rot fungi (Irpex lacteus, Trametes versicolor, Ganoderma lucidum, Polyporellus brumalis, Pleurotus eryngii, Schizophyllum commune) isolated in Korea and two transformants of T. versicolor (strains MrP 1 and MrP 13). I. lacteus degraded 99.4% of 50 mg/l bisphenol A in 3 h incubation and 100% in 12 h incubation. which was the highest degradation rate among the fungal strains tested. T. versicolor degraded 98.2% of 50 mg/l bisphenol A in 12 h incubation. Unexpectedly, the transformant of the Mn-repressed peroxidase gene of T. versicolor, strain MrP 1, degraded 76.5% of 50 mg/l bisphenol A in 12 h incubation, which was a lower degradation rate than wild-type T. versicolor. The removal of bisphenol A by I. lacteus occurred mainly by biodegradation rather than adsorption. Optimum carbon sources for biodegradation of bisphenol A by I. lacteus were glucose and starch, and optimum nitrogen sources were yeast extract and tryptone in a minimal salts medium; however, bisphenol A degradation was higher in nutrient-rich YMG medium than that in a minimal salts medium. The initial degradation of endocrine disruptors was accompanied by the activities of manganese peroxidase and laccase in the culture of I. lacteus.

• 한국환경생태학회지
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• 제14권3호
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• pp.205-211
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• 2000

본연구는 조경소재로 이용가능성이 크지만 현재 자생지가 파괴되어 복원이 요구되고 있는 야생자란의 대량번식을 위해 무균배양시 배지 내 담함량의 변화와 펩톤, 트립톤 등의 첨가가 종자발아와 계대배양 후 유식물의 생육에 미치는 영향을 알아보고자 실시하였다. 배지 내 펩톤과 트립톤의 첨가는 발아에 영향을 주지는 않았지만, 당의 함량은 그 농도가 10g/L까지 증가함에 따라 발아율을 높였다. 또한 발아 후 유식물의 생육시 당의 첨가는 뿌리의 생육을 두드러지게 향상시켰으며, 생체중도 거의 2~3배정도 많았다. 하이포넥스 배지(대조구)에서는 높은 발아율을 보였지만 유식물의 생육은 트립톤 첨가배지(2g/L)에서 많았는데 엽수, 뿌리수, 엽장 근장, 생체중 등이 모두 다른 처리구의 2~3배에 이르는 초기생육을 보였다. 계대배양 이후의 생육상은 펩톤 첨가배지에서 가장 많은 생육량을 보였는데 특히 엽장과 엽폭 그리고 근장이 다른 처리구보다 월등히 높은 경향을 나타냈다. 생체중도 한 개체당 0.18g으로 가장 높게 나타나 펩톤의 첨가가 계대배양 이후의 생육을 크게 촉지시키는 것으로 나타났다. 결론적으로 하이포넥스 배지에 트립톤 2g/L를 첨가하였을 때 발아율과 유식물의 생육이 다른 배지에 대해 매우 양호한 것으로 나타나 자생 자란의 종자발아용 배지로 가장 적당한 것으로 사료된다. 그리고 이후 계대배양시에는 펩톤의 첨가 (3g/L)가 유식물의 생육을 가장 촉진시키는 것으로 나타났다.

• 한국식품위생안전성학회지
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• 제15권2호
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• pp.176-178
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• 2000

V. parahaemolyticus를 균주로 alkaline protease 생산을 위한 질소원의 종류, skim milk농도, NaCl농도, 금속이온의 종류를 조사하였다. 질소원인 peptone, tryptone, casamino acid, ski milk, phyton peptone중에서는 skim milk에서 활성이 월등히 높게 나타났고, skim milk의 농도에 따른 실험에서는 2%일 때 활성이 가장 높게 나타났다. NaCl의 농도에 따른 실험에서는 0%일 때 활성이 가장 높았고 농도가 높아질수록 활성이 낮아졌다. 금속이온에 따른 활성을 보면 금속이온이 들어가지 않았을 때 활성이 가장 높게 나타났고, 금속이온을 첨가하므로써 활성이 급격히 떨어졌다. 또한 CoCl$_2$, CuCl$_2$, HgCl가 첨가되었을 때는 활성이 전혀 나타나지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권11호
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• pp.1582-1585
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• 2004

The antioxidative ability on the basis of reduced glutathione sulphydryl level, the inhibition activities of linoleic acid peroxidation of cell free extract of Lactobacillus spp. and the effects of types of media and growth phase of the cells on the cellular GSH level have been determined. Correlation between reduced glutathione sulphydryl level and antioxidative ability of Lactobacillus spp. was analyzed: Lactobacillus casei HY 2782 contained 25.15 $\mu$mole/g of GSH, the cellular GSH level of L. casei HY 2782 reached maximum after 24 h of cultivation and tended to decrease on further cultivation up to 72 h. There was a significantly higher level of cellular GSH when grown in de Man Rogosa and Sharpe (MRS) broth than in tryptone phytone yeast extract (TPY) broth or bromcresol pruple dextrose (BCP) broth (p<0.05). The antioxidant activity of cell free extract of Lactobacillus spp. have been shown to be significantly different among strains in the inhibition of linoleic acid peroxidation by thiobarbituric acid (TBA) test (p<0.01). L. casei HY 2782 and L. acidophilus ATCC 4356 revealed a high degree of antioxidative effect in linoleic acid oxidation system. Spearmans' rank correlation coefficient between inhibitory activity on linoleic acid peroxidation and cellular GSH levels of Lactobacillus spp. was 0.65, which means a significant positive correlation.

• 한국식품영양과학회지
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• 제24권4호
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• pp.636-641
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• 1995

Proteolytic activities were compared using three species involving in squid jeotkal fermentation and showing positive reaction upon casein test : Pseudomonas D2, Flavovacterium odoratum and Acinetobacter calcoaceticus. Pseudomonas D2 produced highest activity of protease at 72h when incubated in our own modified medium(polypeptone, 0.5% ; tryptone, 0.5% ; NaCl, 3% ; pH, 7.5). Thus, this specie was selected for the further study. The growth pattern was coincided with the production of protease. Thus purification of protease was proceeded by ethanol precipitation, sephadex G-100 gel filtration, and DEAE sepharose ion exchange chromatography. The purified protease showed highest activity at pH 7.0 and 5$0^{\circ}C$. The enzyme was very stable over the wide ragnes of the temperature ; even with one hour heat treatment at 7$0^{\circ}C$, the enzyme showed substantial amount of the activity toward casein. In addition, the enzyme was stable over the wide range of pH. Molecular weight of the protease was determined to be 17.4 kD by SDS-PAGE.

• Preventive Nutrition and Food Science
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• 제9권1호
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• pp.14-20
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• 2004

Bacillus strains capable of producing fibrinolytic enzyme were isolated from traditional fermented Korean soybean paste and Japanese fermented soybean (Natto). Among the 16 strains, a selected Bacillus sp. was identified as bacillus firmus, with 80.7％ homology, by API kit analysis. Seed starter or B. firmus NA-1 was prepared with 5％ soymilk prepared from micronized soybean powder. To produce fibrinolytic enzyme by B. firmus NA-1 the liquid culture was performed with NB broth (pH 7.0) fortified with 1％ galactose, 0.1% tryptone, and 0.5% $K_2$HPO$_4$, by shaking with 180 rpm at 37$^{\circ}C$. Fibrinolytic enzyme activity reached the highest value at 7.8 unit/mL (plasmin unit) after fermentation for 72 hr. The crude fibrinolytic enzyme showed higher relative activity in the range of pH 7.0∼9.0. The activity of crude fibrinolytic enzyme was well maintained even after concentration by the vacuum evaporation at 5$0^{\circ}C$ for 1 hr.

• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.99-107
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• 2009

Strain PUPC1 produces an antifungal protease as well as plant growth promoting enzymes such as 1-aminocyclopropane-1-carboxylate (ACC) deaminase and phosphatase. Morphological, cultural, and physiological characteristics as well as 16S rRNA gene-sequence-based phylogenetic analysis confirmed the taxonomic affiliation of PUPC1 as Chryseobacterium aquaticum. The optimum growth of PUPC1 was observed at pH 6.0 and $30^{\circ}C$, and maximum protease production was observed in medium B amended with 1% tryptone, 0.5% sucrose, and 0.005% $MnCl_2$. The protease was purified by ammonium sulfate precipitation, Sephadex G-75 gel filtration chromatography, and electroelution from preparative SDS-PAGE. The protease had a molecular mass of 18.5 kDa. The optimum pH and temperature stability of the protease were pH 5.0-10.0 and temperature $40-70^{\circ}C$. Chryseobacterium aquaticum PUPC1 and its protease showed a broad-spectrum antifungal activity against phytopathogenic fungi. Strain PUPC1 also exhibited plant growth promoting traits. The objective of the present investigation was to isolate a strain for agricultural application for plant growth promotion and biocontrol of fungal diseases.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.198-201
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• 1989

토양에서 분리, 동정한 Steptomyces sp. GI 32의 glucose isomerase 생산은 sorbitol 1%, yeast extract 0.4%, tryptore 0.6%, 1 mM Fe$_2$(SO$_4$)$_3$의 조성을 가진 배지에서 초기 pH 7.0으로 조절하여 35$^{\circ}C$에서 약 18시간 진탕배양시 효소생산량이 최고로 240 units/mg이었다. 효소는 ammonium sulfate 분획, DEAE cellulose chromatography 등의 과정을 거쳐 부분정제한 결과 3배정도 효소 비활성이 증가하였다. 효소활성의 치적온도는 7$0^{\circ}C$이며, 최적 pH는 8.0이었다. 특히 효소의 열안정성이 7$0^{\circ}C$에서 1시간 가열하여도 전혀 실활되지 않았다.