• Korean Journal of Microbiology
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• v.50 no.1
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• pp.22-26
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• 2014

Protocatechualdehyde (PA) is phenolic compound having antioxidative and antitumor activities. PA was purified from supernatant of Streptomyces lincolnensis M-20. In the presence of copper ion, PA acted as pro-oxidant. The antioxidant activity was assessed with the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, and the pro-oxidant effect of PA on DNA damage as pBR322 plasmid DNA-cleaving agents in the presence of Cu(II) ions was investigated. The involvement of reactive oxygen species (ROS) in the DNA damage was confirmed by the inhibition of the DNA breakage by using glutathione (GSH), specific scavenger of ROS. When the increase in ROS reaches a certain level (the toxic threshold), it may trigger cell death. The formation of the PA/Cu(II) chelate complex was confirmed by reaction with ethylenediamine-tetraacetic acid (EDTA), a well-known chelating agent for metal ions, by using UV/Vis spectroscopic analysis.

• Microbiology and Biotechnology Letters
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• v.29 no.1
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• pp.50-55
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• 2001

A new bacteriocin produced by Bacillus subtilis cx1, was partially purified and characterized. The bactericoin from B. subtilis cx1 was stable in the range of pH 2.5-9.5. B. subtilis csx1 retained its antimicrobial activity to long-term exposure at $-20^{\circ}C$ and $-70^{\circ}C$. However, B. subtilis cx1 was inactivated completely within 15 min over $60^{\circ}C$ and lost 50% of its antimicrobial activity within 15 min at $50^{\circ}C$, B. subtilis cx1 was inactivated by protease, trypsin, proteinase K and carboxypeptidase, which indi-cates its protein nature. Direct detection of the antimicrobial activity on Tricine -SDS-PAGE suggested an apparent molecular mass of about 9,500 dalton.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.373-377
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• 2015

The mature fruit of Sorbus commixta is known as magaja in Korea and is consumed in the form of tea and wine. In addition, it has been used to treat hypertension and articular neuralgia in folk medicine. In this study, the ethanol extract of magaja and its subsequent organic solvent fractions were prepared, and their in vitro anti-coagulation, and platelet aggregation inhibitory activities were evaluated. Among the fractions, the ethylacetate fraction demonstrated significant inhibition against thrombin, prothrombin, blood coagulation factors and platelet aggregation, without hemolysis activity up to 0.5 mg/ml. Our results suggest that the ethylacetate fraction of magaja has the potential to be used as a new anti-coagulation agent.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.235-241
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• 2017

The purpose of this study was to investigate the enhanced physiological activities of two Pichia strains, yeasts isolated from grapes pericarp. Based on phylogenetic analysis using 18S rRNA sequencing, two isolates were identified as Pichia manshurica GU-3 and Pichia terricola GU-4, respectively. The scanning electron microscopic analysis showed that the two isolates grown on YPD medium were of typical elliptical shape with buds and bud scars on cell surface. Physiological activities of the single and mixed Pichia cultures were monitored and compared. In mixed cultures after 72 h of incubation, the maximum activities of tyrosinase inhibition, ACE inhibition, and antioxidant were 81.7%, 45.9%, and 42.7%, respectively. Superoxide dismutase-like activity was approximately 30% in the mixed cultures. These studies demonstrate that Pichia species cultured in the form of mixture can enhance the physiological activities and has potential for the development of new bioactive products.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.268-269
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• 2000

액젓은 신선한 선어를 염장하여 자가소화 효소 및 미생물의 작용에 의하여 원료가 분해ㆍ숙성된 액상의 전통 발효식품으로 예로부터 간장 대용, 김치의 부재료로서 널리 사용되어져 왔다. 액젓은 숙성기간 중에 미생물기원의 단백질분해 효소의 작용에 의하여 어육 단백질이 여러 형태의 Peptide로 분해되어 액젓의 풍미를 향상시키며, 항암, 혈압강화, 혈청콜레스테롤강하, 면역증강, 칼슘흡수 촉진 등 광범위한 생리활성기능을 나타내는 것으로 알려져 있다(M. Messina., 1995). (중략)

• Food Industry And Nutrition
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• v.5 no.3
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• pp.52-56
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• 2000

우리 민족 전래의 발효식품인 김치는 많은 생리활성물질들이 존재하는 다양한 재료를 사용하여 만들어지며 여러 효소와 미생물들이 관여하는 복잡한 발효과정을 거치면서 또다른 생리활성물질들을 생성한다. 이들 물질은 복합적으로 작용하여 항산화활성을 나타내며 실험방법들에 따라 조금씩 다른 양상을 보이지만 김치 재료물질들의 종류 및 함량, 발효정도 등은 김치의 항산화성에 중요한 영향을 미치는 인자들이라고 할 수 있다. 본 총설은 김치의 항산화성을 in vitro 및 in vivo수준에서의 연구결과들을 중심으로 살펴보았다.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2000.11a
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• pp.107-114
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• 2000

우리 민족 전래의 발효식품인 김치는 많은 생리활성물질들이 존재하는 다양한 재료를 사용하여 만들어지며 여러 효소와 미생물들이 관여하는 복잡한 발효과정을 거치면서 또다른 생리활성물질들을 생성한다. 이들 물질은 복합적으로 작용하여 항산화활성을 나타내며 실험 방법들에 따라 조금씩 다른 양상을 보이지만 김치 재료물질들의 종류 및 함량, 발효정도 등은 김치의 항산화성에 중요한 영향을 미치는 인자들이라고 추측할 수 있다. 본 총설은 김치의 항산화성을 in vivo 및 in vivo수준에서의 연구결과들을 중심으로 살펴보았다.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.47-53
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• 2012

Increasing concerns over green farming technology, plant growth promoting rhizobacterium (PGRP) having growth promoting as well as plant disease suppressing properties was recently preferred to use for biological control of plant pathogens infecting plant. We measured the influence of the selected microbial consortium agents-a mixture of PGPR strains-, commercial bio-fungicide, and chemical pesticides on soil microbial community in red pepper field. The activities of soil enzyme such as dehydrogenase, urease, phosphatase, ${\beta}$-glucosidase, and cellulase were analyzed to investigate that of soil microbial community. We also measured plant length, main stem, stem diameter, number of branches and yields of red-pepper in order to observe the red pepper growth promotion. The results of measuring enzyme activities were dehydrogenase 3.5584 ${\mu}g$ TPF $g^{-1}h^{-1}$, urease 15.8689 ${\mu}g$ $NH_4{^-}N$ $g^{-1}h^{-1}$, phosphatase 0.5692 ${\mu}g$ PNP $g^{-1}h^{-1}$, ${\beta}$-glucosidase 2.4785 ${\mu}g$ PNP $g^{-1}h^{-1}$, and cellulase 86.1597 ${\mu}g$ glucose $g^{-1}h^{-1}$ in the soil treated with the microbial consortium agents, so it came out to be very active in the soil. Observing the growth of red-peppers, the main-stem length and the stem diameter were 6.1% and 8.1% higher in the soil treated with the selected microbial consortium agent than the chemical pesticides. After harvesting, yields were 7.3% higher in the soil treated with selected microbial consortium agents than the chemical pesticides. These results showed that microbial consortium agents contribute to increasing soil microbial diversity, growth promoting, and yield of red pepper.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.125-132
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• 2009

In order to develop probiotics which may be a viable alternative of antibiotic use in pig industry, five bacterial strains (Lactobacillus sp. HN 52, 92, 98, 235 and AP 116) possessing antimicrobial properties were selected from 500 strains isolates of pig intestines. The bacteriocin produced by Lactobacillus sp. HN 235 displayed a relative broad spectrum of inhibitory activity against all Enterococcus strains, Pseudomonas aeruginosa, Listeria monocytogenes and Clostridium perfringens using the spot-on-lawn method. The production of antimicrobial substance started in the middle of the exponential growth phase, reached maximum levels (6,400 AU/mL) in the stationary phase, and then declined. Bacteriocin activity remained unchanged after 30 min of heat treatment at $95^{\circ}C$ and stable from pH 2.0 to 10 for 1 h, or exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. The molecular weight of the bacteriocin was about 5 kDa according to a tricine SDS-PAGE analysis.

• Journal of Conservation Science
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• v.24
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• pp.75-83
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• 2008

In order to assess antifungal activity of a wooden storage box, which was made of Paulownia tomentosa and used for keeping ancient documents, antifungal activity of volatile organic compounds emitted from the box was investigated along with qualitative analysis on major substances of the compounds. After collecting floating microorganisms inside air tester, the fungal activity was assessed by counting the number of colonies growing on TSA media. Compared to the control which collected 85 colonies from outdoor, 72 colonies were observed showing reduction rate of 14.82%. Through GC/MS and TDS system analysis, limonene was detected from the volatile organic compounds as characteristic features. When the fungal activity was assessed through fumigation by adding natural biocide BI and BII containing eugenol and anethole as major substances, both biocides showed a strong fungal activity with respectively 92.6%(inside the box) and 99.9%(outdoor) of reduction rate. Although these results didn't clarify antifungal activity of the volatile organic compounds emitted from the Paulownia-wood storage box and their functional components, it was at least confirmed that there is application possibility of natural biocide to use for preservation of ancient documents with increased efficiency in controlling pests of wooden storage boxes.