• International Journal of Industrial Entomology and Biomaterials
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• 제31권2호
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• pp.107-114
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• 2015

Endophytes provide multifarious benefits such as promotion of plant growth and yield, suppression of phyto-pathogens, phosphate solubilising and fixation nitrogen. A study has been carried out to explore growth promotion and antifungal activities of endophytes of mulberry (Morus spp.). Endophytic bacteria were isolated from mulberry plants and studied their cultural, morphological characters, growth promotion as well as their antifungal activity against Rhizoctonia bataticola and Fusarium oxysporum , two mulberry root rot associated pathogens. Except two isolates, all bacteria were colourless and the colony size of eight isolates was small. The margin of five isolates was irregular and the consistency of three isolates was creamy, six isolates was slimy and one was mucoid. Texture of seven isolates was convex and others were flat. Eight isolates were gram positive and the rest Gram negative, five were cocci and others were bacilli (rod shaped). Four isolates were motile and all were catalase positive and only three isolates were oxidase positive. Spore staining was positive only for two isolates. The growth promotion study showed that there was significant difference in root length and seedling length. The antagonistic effect of the bacterial isolates was tested against R. bataticola showed significant (p <0.05) influence of the bacteria, days after inoculation and their interaction on the inhibition of fungal growth. The isolate En-7 completely inhibited the fungus followed by En-5 (66.67%). The bacterial isolates significantly (p <0.05) inhibited growth of F. oxysporum in PDA. The mean inhibition was higher (70.45%) in case of En-7 followed by En-8 (68.65%) and En-10 (66.44%). The study reveals that some endophytic bacteria associated with mulberry have growth promotion and antifungal activity and could be explored for promotion of mulberry growth and managing root rot disease.

• Journal of Dairy Science and Biotechnology
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• 제37권2호
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• pp.83-93
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• 2019

Food spoilage by fungi is responsible for considerable food waste and economical losses. Among the food products, fermented dairy products are susceptible to deterioration due to the growth of fungi, which are resistant to low pH and can proliferate at low storage temperatures. For controlling fungal growth in dairy products, potassium sorbate and natamycin are the main preservatives used, and natamycin is approved by most countries for use in cheese surface treatment. However, a strong societal demand for less processed and preservative-free food has emerged. In the dairy products, lactic acid bacteria (LAB) are naturally present or used as cultures and play a key role in the fermentation process. Fermentation is a natural preservation technique that improves food safety, nutritional value, and specific organoleptic features. Production of organic acids is one of the main features of the LAB used for outcompeting organisms that cause spoilage, although other mechanisms such as antifungal peptides obtained from the cleavage of food proteins and competition for nutrients also play a role. More studies for better understanding these mechanisms are required to increase antifungal LAB available in the market.

• Journal of the Korean Wood Science and Technology
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• 제38권4호
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• pp.341-348
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• 2010

목초액의 농약 또는 식품보존제로서의 이용 가능성을 검토하기 위하여 소나무 및 참나무류 기계식 목초액을 대상으로 항진균 및 항세균 활성을 검정하였다. 그 결과 항진균활성의 경우 미정제 목초액은 0.5% 이상의 농도 에서, 정제 목초액은 1.0% 이상의 농도에서 공시 식물병원균 및 목재부후균의 생장을 완전히 억제하여 미정제 목초액이 정제 목초액보다 항균활성이 높은 것으로 나타났다. 그리고 참나무류 목초액이 소나무 목초액보다 항 균활성이 높아 탄화 원료인 수종에 따라 항균활성의 차이가 있음을 알 수 있었다. 균종별로는 표고 해균인 주홍 꼬리버섯에 대한 항균효과가 다른 공시 균주에 비해 높은 것으로 나타나 균의 종류에 따라 목초액에 대한 감수성이 차이가 있는 것으로 밝혀졌다. 한편, 식품부패균 및 식중독균에 대한 항세균활성을 검정한 결과 소나무 및 참나무류 미정제 목초액의 경우 10% 농도에서 모든 공시 균주에 대해 생육저지환을 형성한 반면 정제 목초액 의 경우에는 저지환을 형성하지 않아 항세균활성도 미정제액이 정제액보다 높은 것으로 나타났다. 균종에 따른 감수성에도 차이가 있어 그람 양성균에 대한 항균활성이 그람 음성균에 비해 상대적으로 높았으나 탄화 원료에 의한 차이는 뚜렷하게 나타나지 않았다. 이상의 결과 목초액은 식물병원균, 목재부후균, 식품부패균 및 식중독 균에 대한 항균활성이 우수하여 유기합성 농약을 대체하거나 식품의 부패를 막기 위한 식품보존제로서 이용이 가능할 것으로 판단되었다.

• Journal of Applied Biological Chemistry
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• 제59권3호
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• pp.173-178
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• 2016

Phenyllactic acid (PLA), which is a known antimicrobial compound, can be synthesized through the reduction of phenylpyruvic acid (PPA) by lactate dehydrogenase of lactic acid bacteria (LAB). PLA-producing LAB was isolated from coffee beans, and the isolated LAB was identified as Lactobacillus zeae Y44 by 16S rRNA gene sequence analysis. Cell-free supernatant (CFS) from L. zeae Y44 was assessed for both its capability to produce the antimicrobial compound PLA and its antifungal activity against three fungal pathogens (Rhizoctonia solani, Botrytis cinerea, and Colletotrichum aculatum). PLA concentration was found to be 4.21 mM in CFS when L. zeae Y44 was grown in MRS broth containing 5 mM PPA for 12 h. PLA production could be promoted by the supplementation with PPA and phenylalanine (Phe) in the MRS broth, but not affected by 4-hydroxy-phenylpyruvic acid, and inhibited by tyrosine as precursors. Antifungal activity assessment demonstrated that all fungal pathogens were sensitive to 5 % CFS (v/v) of L. zeae Y44 with average growth inhibitions ranging from 27.8 to 50.0 % (p<0.005), in which R. solani was the most sensitive with an inhibition of 50.0 %, followed by B. cinerea and C. aculatum. However, pH modification of CFS to pH 6.5 caused an extreme reduction in their antifungal activity. These results may indicate that the antifungal activity of CFS was caused by acidic compounds like PLA or organic acids rather than proteins or peptides molecules.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.95.2-96
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• 2003

In order to develop a new microbial fungicide for the control of vegetable diseases using endophytic bacteria, a total of 260 bacterial strains were isolated from fresh tissues of 5 plant species. After they were cultured in broth media, their antifungal activities were screened by in vivo bioassays against Botrytis cinerea(tomato gray mold), Pythium ultimum(cucumber damping-off), Phytopkhora infestans(tomato late blight), Colletotrichum orbiculare(cucumber anthracnose), and Blumeria graminis f. sp. hordei(barley powdery mildew). As the results of screening, 38 bacterial strains showed potent antifungal activities against at least one of 5 plant pathogens. A bacterial strain EB072 displayed potent disease control activities against 3 plant diseases. Among the bacterial strains with a potent antifungal activity against cucunlber anthracnose, three bacterial strains, EB054, EB151 and EB215, also displayed a potent in vitro antifungal activity against C. acutatum, a fungal agent causing pepper anthracnose. A bacterial strain EB215 obtained from roots of cucumber was identified as Burkholderia cepacia based on its physiological and biochemical characteristics and 165 rRNA gene sequence. An antifungal substance was isolated from the liquid cultures of B. cepacia EB215 strain by ethyl acetate partitioning, repeated silica gel column chromatography, and invitro bioassay, Its structural determination is in progress by various instrumental analyses.

• 한국유기농업학회지
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• 제14권4호
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• pp.399-410
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• 2006

전남 남부지역의 참다래 과수원에서 발생하는 잿빛곰팡이 병원균(gray mold, Botrytis cinerea)에 대한 항균작용이 우수한 세균성 균주를 선발하기 위하여 참다래 과수원 토양으로부터 단일균주를 분리하였으며, 잿빛곰팡이 병원균(Botrytis cinerea)에 대한 생물적 제어 능력을 검정하고 균주 동정을 실시하였다. 참다래 과수원에서 분리한 총 350여종의 단일균 주 중에서 참다래에서 발생하는 잿빛곰팡이 병원균에 대하여 길항작용이 우수한 균주를 1차적으로 4종 선발하였고, 이 중에서 참다래 잿빛곰팡이 병원균에 대하여 길항작용이 86.9% 정도로 우수한 CHO 163을 최종적으로 선발하였다. 참다래 잿빛곰팡이 병원균에 대하여 길항작용이 우수한 CHO 163을 대상으로 균주의 형태적 성질, 배양적 특성 및 생리 생화학적 성질 등을 조사하여 균주의 동정을 검토한 바 Bacillus sp.와 유사한 균주로 동정되었다. 길항균으로 분리한 Bacillus sp. CHO 163은 한천배지에서 참다래 잿빛곰팡이 병원균 접종 후 길항균 처리와 열처리한 균주 배양액을 처리하였을 때 거의 완전한 항균작용을 보였다. 또한, in vitro 상에서 참다래에 잿빛곰팡이병원균을 접종하고 Bacillus sp. CHO 163의 배양액을 처리한 결과 잿빛곰팡이병원균의 방제가 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.1015-1020
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• 2012

Antifungal cement mortar or microbiological calcium carbonate precipitation on cement surface has been investigated as functional concrete research. However, these research concepts have never been fused with each other. In this study, we introduced the antifungal calcite-forming bacteria (CFB) Bacillus aryabhattai KNUC205, isolated from an urban tunnel (Daegu, South Korea). The major fungal deteriogens in urban tunnel, Cladosporium sphaerospermum KNUC253, was used as a sensitive fungal strain. B. aryabhattai KNUC205 showed $CaCO_3$ precipitation on B4 medium. Cracked cement mortar pastes were made and neutralized by modified methods. Subsequently, the mixture of B. aryabhattai KNUC205, conidiospore of C. sphaerospermum KNUC253, and B4 agar was applied to cement cracks and incubated at $18^{\circ}C$ for 16 days. B. aryabhattai KNUC205 showed fungal growth inhibition against C. sphaerospermum. Furthermore, B. aryabhattai KNUC205 showed crack remediation ability and water permeability reduction of cement mortar pastes. Taken together, these results suggest that the $CaCO_3$ precipitation and antifungal properties of B. aryabhattai KNUC205 could be used as an effective sealing or coating material that can also prevent deteriorative fungal growth. This study is the first application and evaluation research that incorporates calcite formation with antifungal capabilities of microorganisms for an environment-friendly and more effective protection of cement materials. In this research, the conception of microbial construction materials was expanded.

• 한국유기농업학회지
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• 제12권2호
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• pp.183-196
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• 2004

This study was carried out to screen and select the effects of antifungal bacterial strains which inhibit the growth of plant pathogen, Fusarium oxysporum(fusarium wilt) occurred in carnation plants in greenhouse. We isolated an effective bacterial strains and investigated into the antifungal activity of the antagonistic microorganism and it's identification. Twenty bacterial strains which strongly inhibited Fusarium oxysporum were isolated from roots of carnation plants and the soil in greenhouse, and the best antifungal bacteria designated as C121, was finally selected. Antagonistic bacterial strain, C121 was identified to be the genus Bacillus sp. based on the morphological, biochemical and cultural characterizations. The Bacillus sp. C121 showed 58.1% of antifungal activity against the growth of Fusarium oxysporum. By the bacterialization of the cultural broth and the heat bacterialization culture filtrate of it, Bacillus sp. C121 was shown 92.1% and 21.0% of antifungal activity, respectively.

• 한국토양비료학회지
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• 제50권6호
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• pp.598-605
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• 2017

To isolate rhizobacteria exhibiting antifungal activities for for five pathogenic fungi (Sclerotinia sclerotiorum, Fusarium solani, Collectotricum gloeosporides, Fusarium oxysporum, and Botrytis cinerea) which cause damage to Ginseng root in Ginseng grown fields, four soils were collected from Cheorlwon gun, in Korea. From 4 soils, a total of 160 bacterial strains were isolated by dilution plate method. Among 160 strains, 32 strains showed antifungal activities for one or more pathogens. From 32 strains, three strains exhibited antifungal activities for all pathogens. These are two Burkholderia cepacia (ATCC 25416 and ET 13) and one Paenibacillus polymyxa (ATCC 842). These potent antifungal strains showed high identities (99% using 16S-rRNA sequencing).

• 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.