• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.805-810
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• 2000

An antifungal protein antagonistic to the rice blast fungus, Pyricularia oryzae was purified from Paenibacillus macerans PM-1 by ammonium sulfate fractionation, Q Sepharose Fast Flow column chromatography, Phenyl Sepharose CL-4B column chromatography and Superose 12 gen filtration. An apparent molecular mass of the purified antifungal protein was determined as 8 kDa by SDS-PAGE and 9 kDa by analytical gel filtration, respectively, suggesting that the purified protein is a monomer. The antifungal protein was stable at pH range from 7-12 and up to $100^{\circ}C$. The protein was also stable at 0.1-1% Tween 20 and Triton X-100. The N-terminal amino acid sequence of the antifungal protein was Thr-Glu-Leu-Pro-Leu-Gly-Ile-Val-Met-Asp-Lys-Tyr-Thr-Asp-Ala-Phe-Lys-Phe-Asp-Met-Phe. Comparison of the determined sequence with other peptide and DNA sequences did not reveal homology at all. Therefore, the purified antifungal protein was speculated to be a novel protein. The condidial germination in vitro of P. oryzae KJ301:93-39 by the purified protein ($5.9{\mu} g/ml$) was limited to $9{\pm}3.2%$ only, compared with $69{\pm}2.4%$ of the control. Ungerminated conidia were swollen at basa and mid cell by the purified protein. In vivo bioassay for inhibition of conidial germination of P. oryzae KJ 301, one of the most predominating racesin Korea. the purified protein ($5.9{\mu} g/ml$)strongly inhibited the conidial germination. The conidia, even though germinated, could not develop any further to produce appressoria efficiently.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1322-1326
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• 2013

New antifungal agents are required to compensate for the increase in resistance to standard antifungal agents of Candida albicans, which is an important opportunistic fungal pathogen that causes minor infections in many individuals but very serious infections in those who are immune-compromised. In this study, combinations of theaflavin and epicatechin are investigated as potential antifungal agents and also to establish whether antifungal synergy exists between these two readily accessible and cost-effective polyphenols isolated from black and green tea. The results of disc diffusion assays showed stronger antibacterial activity of theaflavin:epicatechin combinations against C. albicans NCTC 3255 and NCTC 3179, than that of theaflavin alone. Minimum inhibitory concentrations (MICs) of 1,024 ${\mu}g/ml$ with theaflavin and 128-256 ${\mu}g/ml$ with theaflavin:epicatechin combinations were found. The fractional inhibitory concentration indexes were calculated, and the synergy between theaflavin and epicatechin against both isolates of C. albicans was confirmed. Theaflavin:epicatechin combinations show real potential for future use as a treatment for infections caused by C. albicans.

• Molecules and Cells
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• 제28권5호
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• pp.473-477
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• 2009

Previously, the 9-mer analog peptides, 9Pbw2 and 9Pbw4, were designed based on a defensin-like peptide, protaetiamycine isolated from Protaetia brevitarsis. In this study, antifungal effects of the analog peptides were investigated. The antifungal susceptibility testing exhibited that 9Pbw4 contained more potent antifungal activities than 9Pbw2. A PI influx assay confirmed the effects of the analog peptides and demonstrated that the peptides exerted their activity by a membrane-active mechanism, in an energy-independent manner. As the noteworthy potency of 9Pbw4, the mechanism(s) of 9Pbw4 were further investigated. The membrane studies, using rhodamine-labeled giant unilamellar vesicle (GUV) and fluorescein isothiocyanate (FITC)-dextran loaded liposome, suggested that the membrane-active mechanism of 9Pbw4 could have originated from the pore-forming action and the radii of pores was presumed to be anywhere from 1.8 nm to 3.3 nm. These results were confirmed by 3D-flow cytometric contour-plot analysis. The present study suggests a potential of 9Pbw4 as a novel antifungal peptide.

• 생명과학회지
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• 제16권3호
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• pp.420-426
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• 2006

노르웨이의 Oslo시 지역의 토양시료로부터 분리된 Bacillus sp. KMU-991를 이용하여 고추탄저병균인 Colletotruchum gloeosporioides KACC 40804에 대한 항진균 활성을 위한 배양 조건을 조사하였다. 항진균 물질의 생산은 기본배지로 TSB를 사용하였으며 탄소원으로 1.0% mannitol과 질소원으로 1.0% ammonium chloride를 첨가하였을 매 가장 높은 항진균 활성을 나타내었다. 배양조건으로는 $30^{\circ}C$, 180 rpm, 48시간 배양하였을 때 가장 높은 항진균 활성을 나타내었다. $30{\sim}60%$ ammonium sulfate 침전물을 첨가하였을 때 가장 양호한 항진균 활성을 나타내었으며 butanol을 이용하여 배양액 중에 존재하는 항진균 물질을 회수하여 다양한 작물병원성 곰팡이에 대한 spectrum을 조사한 결과 B. cinerea KACC 40573, C. orbiculare KACC 40808, F. oxysporum f. sp. radicus-lycopersici KACC 40537, P. cambivora KACC 40160, 그리고 R. solani AG-4 KACC 40142등에 대하여도 높은 항진균 활성을 나타내었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.103-103
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• 2019

Glycyrrhizae radix, commonly known as licorice, is a perennial herb belonging to Leguminosae and also includes various components such as, glycyrrhizin, liquiritin, liquiritigenin and isoliquiritigenin etc. Licorice has been widely used in East Asia as a medicine having pharmacological effects like antioxidants, anti-bacterial, anti-inflammatory, anti-cancer and immune modulatory activities. Among various licorice, Glycyrrhiza (G.) uralensis G. glabra and G. inflata are used for pharmaceutical purposes in Korea. However, cultivation of licorice has some problems such as low quality, low productivity, and early leaf drop. Korea Rural Development Administration developed new cultivars Wongam and Sinwongam, which are improved in cultivation and quality. To register the newly developed cultivar (s) on Ministry of Food and Drug Safety in Korea as a medicine, it is necessary to prove the similarity and difference through the comparative studies between already-registered species and new cultivars. Some fungi and bacteria usually in the human oral cavity and intestines exist as harmless state in human body. Also, the skin and genital infections by fungi can lead to toxic systemic infections and are accompanied by flushing, rashes, burning or painful sensation. The influences of licorice varieties on fungi and bacteria might be an evidence to prove the outstanding effect of newly developed licorice variety. In this study, the antifungal and antibacterial activity was investigated using newly developed licorice varieties Wongam, and Sinwongam against various fungi and bacteria. These results means newly developed licorice could be used as a replacement of already-registered species in terms of antifungal and antibacterial application.

• 한국유기농업학회지
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• 제8권3호
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• pp.121-130
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• 2000

사과 저장중에 발생하는 푸른곰팡이병원균에 대한 길항미생물을 찾기 위하여 자연계로부터 유용미생물을 분리하여 Penicillum expansum에 대한 길항력 검정과 동정하였다. 자연계로부터 얻은 3,000여종의 미생물중에서 푸른곰팡이병원균에 대하여 길항력이 우수한 미생물을 1차적으로 11종 선발하였으며, 이중에서 가장 길항력이 뛰어난 미생물을 치종적으로 KB22를 선발하였다. 길항력이 우수한 KB22의 형태적 성질, 배양적 특성 및 생리 생화학적 성질 등을 조사하여 비교 검토한 결과 Bacillus subtilis와 유사한 균으로 동정되었다. 분리한 길항균 Baillus subtilis KB22는 푸른곰팡이병에 대한 55.9%의 높은 생장억제력을 보였으며, 한천배지에서 Penicillum expansum 접종 후 길항균처리와 열처리한 길항균배양액을 처리하였을 때 각각90%와 15%이상 길항력을 보여주었다.

• Applied Biological Chemistry
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• 제46권3호
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• pp.268-270
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• 2003

굴피나무 지상부의 메탄을 추출물을 n-hexane, ethylacetate, n-butanol, $H_2O$으로 순차적으로 용매분획하였다. Ethylacetate 분획으로부터 silica gel chromatography를 반복하여 활성물질을 분리 정제하였다. 화합물은 NMR과 MS의 기기분석 결과 5-hydroxy-2-methoxy-1,4-naphthoquinone로 구조결정 되었다. 이 화합물은 in vivo 실험결과 토마토역병에 대하여 $100\;{\mu}g/ml$에서 76%의 방제효과를 나타내었다.

• Environmental Analysis Health and Toxicology
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• 제8권3_4호
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• pp.7-12
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• 1993

An Actinomycete strain isolated from Mt. Dea-Dun had a strong antifungal activity. The culture brith produced by isolated strain showed only antifungal activity against fungi with the exception of yeast and bacteria. It was heat stable, dissolved in ehtylacetate. The concentrated antifungal agent showed cytotoxicity against HEP-2 and HeLa as tumor cell line, and showed weak cytotoxicity against VERO 36 as normal cell line. Morphological and physiological characteristics were tested with isolated strain. The spore color of isolated strain was gray. It had a short chain and produced brown colored lytic substance in yeast extract-malt agar. The cell wall of isolated strain was composed of meso-DAP, and we suggested it as genus Actinomadura. In the existing of chemical inhibitor, isolated strain grew on the condition of 0.0001% crystal violet, 0.1% phenol, 0.01% sodium azide and 10% sodium chloride. Carbon utilization of isolated strain was shown that glucose, sucrose, manitol and sodium citrate were well utilized.

• 생명과학회지
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• 제14권1호
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• pp.193-197
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• 2004

A continuous enrichment culture procedure was used to isolate bacteria from various soil sources capable of suppressing large patch disease of turfgrass. Six isolates consistently suppressed large patch in turfgrass, and ranged in the spectrum of extracellular enzymes that they expressed. The best disease- suppressing isolate, TBM912, expressed protease, CMCase, and pectinase activity and inhibited the growth of Rhizectonin solani and Betrytis cinerea in vitro. Here we show that this strain also produces an antibiotic that was identified by TLC, SDS-PACE and HPLC analysis as lipopeptide.

• BMB Reports
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• 제38권1호
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• pp.82-88
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• 2005

Bacillus cereus 28-9 is a chitinolytic bacterium isolated from lily plant in Taiwan. This bacterium exhibited biocontrol potential on Botrytis leaf blight of lily as demonstrated by a detached leaf assay and dual culture assay. At least two chitinases (ChiCW and ChiCH) were excreted by B. cereus 28-9. The ChiCW-encoding gene was cloned and moderately expressed in Escherichia coli DH5$\alpha$. Near homogenous ChiCW was obtained from the periplasmic fraction of E. coli cells harboring chiCW by a purification procedure. An in vitro assay showed that the purified ChiCW had inhibitory activity on conidial germination of Botrytis elliptica, a major fungal pathogen of lily leaf blight.