• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.266-270
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• 1994

A bacteriocin was isolated from the supernatant fluid of M17G broth culture of Lactococcus sp. HY 449 strain, which showed strong inhibitory activity against the growth of selective indicator strain, Lactobacillus fermentum IFO3023. When the bacteriocin wasa added to the growing indicator cells or cell suspensions, viable cells and optical density were density were decreased, indicating bacteriolytic mode of action. Electron microscopic observation of indicator cells treated with bacteriocin revealed apparent damages on the cell surface and eventual lysis of cell walls.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.882-887
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• 1996

Production of yeast diet has been carried out in batch fermenters under optimum culture conditions. The fermentation of Candida utilis on a $2\%$ complex medium resulted in 1.22 g/L/h productivity and $65\times10^8$ viable cells/ml, and the addition of $15{\mu}M$ zinc to the medium increased both the productivity and the number of viable cells just a little more. In the case of the fermentation of Kluyveromyces fragilis, the highest value of the biomass productivity, 1.94 g/L/h, was obtained on a $2.5\%$ fructose medium with $70\times10^8$ viable cells/ml, and $1\%$ peptone was found to be a growth factor in this fermentation. When $3.5\%$ NaCl was added to the given medium, both the biomass productivity and the number of viable cells decreased significantly in each fermentation, but this may be considered to preserve yeast diet long without osmotic lysis.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.167-170
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• 2008

A fungal strain BCP, which parasitizes Botrytis cinerea gray mold pathogen, was isolated and identified as Acremonium strictum. BCP strain overgrew the colonies of B. cinerea and caused severe lysis of the host hyphae. Frequent penetration and hyphal growth of A. strictum BCP inside the mycelia of B. cinerea were observed under light microscopy. In addition, some morphological abnormalities such as granulation and vacuolation of the cytoplasm were observed in mycelia and spores of B. cinerea. In dual culture test, A. strictum BCP strongly inhibited the mycelial growth of several plant pathogenic fungi as well as B. cinerea. To our knowledge, this is the first report on mycoparasitism of Acremonium species on B. cinerea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.29-32
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• 2015

Two-dimensional electrophoresis (2-DE) was executed to separate the seed storage proteins from the buckwheat. The proteins extracted from the whole seed proteins were better separated and observed in the use of lysis buffer. Using this method, the highly reproducible isoelectric focusing (IEF) can be obtained from polyacrylamide gels, and IEF from the polyacrylamide gel at all the possible pH range (5.0-8.0) was more easily separated than IPG (immobilized pH gradient) gels. The polyacrylamide gels in the first dimension in 2-DE was used to separate and identify a number of whole seed proteins in the proteome analysis. In this new apparatus using 2-DE, 27cm in length of plate coated with polyacrylamide gel was used and the experiment was further investigated under the various conditions.

• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.263-268
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• 1993

Seventeen strains were isolated from soil, cattle rumen, cereal sewage dregs, insect on agar plate containing insoluble glucan as a sole carbon source from immobilized Streptococcus mutans, which produced alpha-1,3 glucanase for lysis of dental plaque. Among these strains isolated from soil, SW-522 and SW-713 that had appeared to produce the high level of alpha-1,3 glucanase, degraded insoluble glucan from S. mutans 97.6% and 49.4%, respectively in 5 hours. The activity of crude alpha-1,3 glucanase from SW-522 was 1.3mg insoluble glucan/min.mg protein. This enzyme was entirely degraded insoluble glucan on glass tube which produced by S. mutans in TH medium with 5% sucrose.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.186-191
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• 2015

Diatoms are a major component of the biological community, serving as the principal primary producers in the food web and sustaining oxygen levels in aquatic environments. Among marine planktonic diatoms, the cosmopolitan Skeletonema costatum is one of the most abundant and widespread species in the world's oceans. Here, we report the basic characteristics of a new diatom-infecting S. costatum virus (ScosV) isolated from Jaran Bay, Korea, in June 2008. ScosV is a polyhedral virus (45-50 nm in diameter) that propagates in the cytoplasm of host cells and causes lysis of S. costatum cultures. The infectivity of ScosV was determined to be strain- rather than species-specific, similar to other algal viruses. The burst size and latent period were roughly estimated at 90-250 infectious units/cell and <48 h, respectively.

• Natural Product Sciences
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• v.7 no.4
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• pp.114-119
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• 2001

The effect of Rhinacanthus nasutus leaf extract on the growth of dermatophytes had been investigated. In vitro the extract exhibited high activity against various species of dermatophytes (Trichophyton mentagrophytes var. mentagrophytes, T. mentagrophytes var. interdigitale, T. rubrum, Microsporum canis and M. gypseum). The minimal inhibitory concentration (MIC) values of the extract revealed that all the dermatophytes tested had MIC values of 13.6 mg/ml. The extract exhibited fungistatic activity at lower concentrations $({\leq}13.6\;mg/ml\;or\;below\;the\;MIC\;value)$ and fungicidal activity at higher concentrations $({\geq}13.6\;mg/ml$\;or\;above\;the\;MIC\;value)$. The results suggested that the extract acted on the cell wall of the dermatophytes which subsequently leading to the formation of cytopathological and membrane structural degeneration and finally leading to cell lysis and death.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.61-61
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• 1995

1993년 국내토양으로부터 분리동정된 Streptomyces속 균주중 항종양성이 우수한 균주 3주(DKM104, DKM117, DKM409)를 선정하고 이들을 대량 배양하여 종양억제인자를 분리하고 시험관내 종양세포 독성능 및 생체내 항암활성능과 이들 물질생산과 PLASMID DNA와의 관련성, $LD_{50}$등을 시험하여 새로운 항종양물질의 개발을 목적으로 하였다. 분리선별균주의 배양조건을 확립하였으며 배양여액을 국성이 적은 유기용매로부터 큰쪽으로 단계적으로 유효성분을 추출하여 Gel Chromatography를 이용하여 유효성분을 분획하였다. 시험관내 항종양능 시험은 MTT colorimetric검정법을 이용하여 $IC_{50}$값을 산정하였으며 생체내 항종양능은 마국의 NIC에서 권장하는 tumor panel system에 따랐다. 선정된 균주의 plasmid 분리는 alkalin lysis법을 채택하였으며 agarose gel electrophoresis로 plasmid profile을 시험하였다. Novobiocin등을 이용하여 Curing test를 시행하였고 독성실험은 $LD_{50}$량을 구해 항암효과 측정시에 Maximum dost로 투여하였고 최고용량을 기준으로 일정한 공비를 적응하여 3단계의 투여량을 설정하였다.(중략)

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.101-106
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• 1993

The optimal conditions for the production and regeneration of L. helveticus protoplasts were examined. The protoplast formation of L. helveticus was most efficient obtained when the cells grown to mid and late logarithmic phase in MRS medium were used. The maximum number of protoplasts was obtained when lysozyme and mutanolysin were used to lysis the cell wall in 20mM HEPES buffer (pH 7.0) containing 1M sucrose. Regeneration was accomplished with a complex medium containing 10% sucrose, 10mM MaCl2, 20mM CaCl2, 5% gelatin and 0.5% bovine serum albumin. The regeneration frequency of the protoplasts was 10-20% after 5 days of incubation at 30C.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.243-244
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• 2001

Vibrio choleae non-O1 has been reported to cause food borne gastroenteritis. This strain produces therm()stable direct hemolysin (NAG-rTDH) similar with that of Vibrio parahaemolyticus. As a result of rabbit ligated intestinal loop test, TDH caused fluid accumulation and is considered to be the major virulent factor. Hemolysis by TDH has been reported to cause colloid osmotic lysis of erythrocytes. (omitted)