• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.04a
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• pp.98.5-99
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• 1978

항생물질과 RNA 분해효소를 동시에 생산하는 방선균의 한 균주를 토양으로부터 분리하여 이 균주가 생산하는 RNA 분해효소의 물리화학적 성질 및 분해산물에 대해 검토하였다. 효소반응의 최적 pH 및 온도는 명명 pH 5.6과 $50^{\circ}C이었다.$ $37^{\circ}C$ 에서 90분간 열처리 시켰을 때, 이 효소의 활성은 비교적 안정하였지마는 $50^{\circ}C$ 에서 90분간 열처리 시켰을 때는 효소활성이 심하게 저하되었다. 이 효소의 활성은 $Ba^{2+}$ 에 의하여 50% 정도의 저해 작용을 나타내었지만 EDTA에 의해서는 저해되지 않았다. 이 효소에 의한 RNA분해로 이 효소가 대사산물로서 guanosine, adenosine과 밝혀지지 않은 두 가지의 핵산관연물질을 생산함을 알 수 있었다. 제2보에서는 ENase의 효소학적 성질을 검토하였으며 이후 항생물질 측면에서 검토할 예정이다.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.13-17
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• 1993

When mandarin orange peel was used for a substrate of citric aCid fermentation by Aspergillus niger, principal enzyme activities were investigated. Not only the activity of polygalacturonase and pectin esterase being capable of digesting pectin and crude fiber of mandarin orange peel. but also that of carboxymethyl cellulase, xylanase and amylase was high. In carbohydrate metabolism, the activity of enzymes related in HMP pathway was higher than that in EMP pathway at the orange peel medium designed hereby rather than synthetic medium. Productivity of citric acid was significantly increased when the activity of citrate synthetase was high and 5imultaneously those of aconitase and NADP-dependent dehydrogenase were low.

• The Microorganisms and Industry
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• v.15 no.2
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• pp.54-56
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• 1989

19세기 초기까지 인류가 사용해왔던 약물들은 동식물및 광물질 기원의 물질을 단순하게 처리한 것들이었다. 그 이후 화학의 발달및 필수적인 생리활성 검색법의 개발에 의해 비로소 현대적인 의미의 약물학(Pharmacology)의 시대가 열리게 되었다. 화학의 발달에 의해 오래전부터 사용되던 약제 중의 유효성분의 분리, 정제, 확인과 신물질의 합성이 가능해졌으며, 생리활성 검색법의 개발에 의해 유효성의 측정및 약물의 생체내 작용기전의 확인이 연구될 수 있었다. 일단 이러한 필수적인 도구와 테크닉이 주어지자 신약개발은 관련분야의 급속한 발달과 보조를 같이하여 가속적으로 발전하였으며 여기에 의약품 제조업의 성장이 자극제로 작용하였다. 그 결과 신개발약물의 양적인 팽창, 약물에 의해 조절될 수 있는 질병의 증가 및 약물작용기전의 이해등의 성과가 얻어질 수 있었다. 신개발약물의 수는 세계 제2차대전 종료후 10여년 사이에 최대에 달하였으나 그후 신약의 허가에 수반되는 법령의 강화에 따라 감소하기 시작하여 현재는 거의 일정한 수준을 유지하고 있다.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.307-310
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• 2004

본 연구에서는 분리대두단백(ISP: isolated soy protein)과 탈지대두박(DSF: defatted soy flake)을 Devolase Flavourzyme 효소로 가수분해한 각각의 HVP를 발효 배지로 사용하여 Candida utilis(KCCM 50342) 효모의 ethylalcohol, 4-ethylguaiacol의 생성과 향 생성의 주요 인자인 a -galactosidase의 활성을 측정하였다. Ethylalcohol은 발효 1일째에 탈지대두박을 원료로 하고 여과후 미생물 처리한 경우에서 가장 높게 생성되었고, 4-ethylguaiacol은 일부 여과하지 않고 미생물 처리한 경우에서 낮은 농도의 생성을 보였다. a-galactosidase 효소활성은 탈지대두박 보다 ISP를 원료로 한 HVP에서 높은 활성을 보였다. 관능검사결과 탈지대두박을 사용한 HVP의 관능적 특성이 ISP를 원료로 한 HVP보다 더 우수하였다. 결과적으로 탈지대두박을 원료로 한 HVP의 향기성분 및 관능적 특성이 우수함을 확인하였다.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.1969-1976
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• 2000

It is a time consuming work to identify the inhibition of unknown chemicals or industrial wastewater. Thus it is needed to establish a fast assay tool for finding a toxicant source. Biomass activity and ammonia inhibition were measured by DHAINT method. Ammonia inhibition tests were comprised of total ammonia inhibition and free ammonia inhibition. Those inhibitions were carried out by nitrifier and heterotroph each other with nitrifier inhibitor. The ammonia inhibition was proportional to an amount of total ammonia and pH increase. It meaned that a free ammonia played a key role for ammonia inhibition. however both total ammonia and free ammonia should be considered for an accurate assay of the ammonia inhibition. Nitrifier was more sensitive than heterotroph when the ammonia concentration above 3.000mg/L.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.13-23
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• 1999

In this research, 3-hydroxypyridine(2-HP) metabolic ability of starving Arthrobacter crystallopoietes cell and the effect of humic acid on the metabolism of this starving cell were evaluated. 2-HP metabolic ability of exponential phase cell (acclimated cell) was much higher than that of lag phase cell (unacclimated cell) during starvation period. After 3 days of starvation, 2-HP half-life of the acclimated cell was 14 hours and that of the unacclimated cell was 46.5 hours. Humic acid enhanced the stability of 2-HP monooxygenase of starving co]1 and, after 2 days of starvation, the residual activity rate of this enzyme of the microbial cell starved in humic acid solution was 12% while the rate for control condition was 1.5%. After 14 days of starvation, 2-HP half-life for control condition was 43 hours and that for humic acid condition was 1.25 hour.

• Journal of the Korean Applied Science and Technology
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• v.38 no.4
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• pp.1010-1019
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• 2021

Petroleum oil in reservoir has been acquired by primary, secondary and tertiary oil recoveries. Microbial enhanced oil recovery (MEOR) classified to tertiary oil recovery has been evaluated in two ways of in-situ and ex-situ options. In-situ MEOR injects microbes into a depleted oil reservoir and stimulates those to generate metabolites. Among metabolites, biosurfactants play an important role to make heavy residues flow. Ex-situ MEOR injects microbial metabolites instead of microbes into a reservoir to recover oil. Even though both in-situ MEOR and ex-situ MEOR are eco-friend processes, in-situ MEOR can be preferred because it is more economic. Even though MEOR have been evaluated for a long time, it is still in the state of evaluating in a pilot-scale. Among microbes, bacteria have been widely evaluated in MEOR purpose. In this paper, bacteria for MEOR were summarized and their metabolites were qualitatively evaluated.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.124-128
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• 2003

In order to isolate and characterize a novel fungal strain capable of producing cellulase, each samples of the old rice straw, soil, and the old tree were screened by congo red test. One of the fungi screened has been identified as Aspergillus tubingensis strain from the results of the phylogenic analysis based on partial DNA sequence and the basis of its biochemical properties. A carboxymethyl cellulase activity of the strain was higher than that of A. oryzae KCTC 6291. In CMCase activity measurement, it wasn't sensitive about pH 2.0, 3.0, 4.0, but the enzyme was more stable than A. oryzae under the various pH and temperature conditions and the enzyme activity was more similar to neutrality and alkali. Therefore, it could be suggested that the isolated strain has a potential possibility for the developing of the probiotics.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.305-308
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• 2012

In this study, we evaluated antifungal and antioxidant activities of condensed liquid of volatile organic compounds generated during the drying process of Chamaecyparis obtuse. Condensed liquid of volatile organic compounds were extracted with hexane and ethyl acetate, respectively. The extracts were used for antifungal activity at range from 100 to 500 mg/L Antifungal activity of extracts increased as the extracts concentration increased, the activity against tested dermatophytes was high at 500 mg/L. Among extract solvents, antifungal activity was higher at hexane extract than the ethyl acetate. Especially, the antifungal activity against Trichophyton rubrum was higher than other tested dermatophytes. Antioxidant activity was 90% above 25 mg/L regardless of the extractive solvents, while the hexane extract showed high antioxidant activity below 25 mg/L. Major compounds of hexane extract were torreyol, alpha-cadinol, and tau-cadinol. However, major compounds of ethyl acetate extract were alpha-amorphene, alpha-cadinol, and gamma-cadinene.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.153-158
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• 1996

During the screening of herbicidal substances from microbial secondary metabolites using photoautotrophic cells, a strain of ME-13 with strong herbicidal activity was isolated from soil. Based on the taxonomic studies, the strain was identified as Streptomyces. Two active compounds were purified from the culture broth through the column chromatographies using active charcoal, silica gel, MCI gel, and ODS HPLC. The compounds were identified as AB3217-A and B, respectively, related to anisomycin by spectroscopic methods. AB3217-A and B completely suppressed the germination of radish and barnyard grass at 25 ppm. In comparison to anisomycin, they showed the 6 times higher inhibitory activities against the growth of shoot and root of radish and barnyard grass with EC5O of around 6 ppm.