• KSBB Journal
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• v.28 no.6
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• pp.400-407
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• 2013

The growth characteristics and production of color pigments by Monascus strains were investigated during liquid culture, and production of monacolin K in red mold rice was carried out by solid state fermentation. Four different Monascus ruber strains were cultured in potato dextrose yeast extract broth (PDYB) media at $25^{\circ}C$ for 15 days. The high producing strain for red pigment was not corresponded to the strain for yellow pigment. Production of red pigment was high in the strain causing the fast pH change in culture broth. Production of monacolin K in red mold rice by solid state fermentation was influenced by a combination of wet cell weight and spore density in inoculum by liquid culture. Most strains showed the high production of monacolin K in red mold rice, when submerged fermentation was carried out for 5 days as inoculum for solid state fermentation. These results suggest that submerged fermentation period of inoculum have an effect on the production of monacolin K in red mold rice by solid state fermentation, and monacolin K in red mold rice could be increased by controlling the condition of submerged fermentation for inoculum.

• The Korean Journal of Food And Nutrition
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• v.6 no.1
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• pp.1-7
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• 1993

19 Samples of koji-starters using in brewing were collected from Korea and Japan, and then 31 strains of koji-molds were isolated from them. After Identification of the Isolate, rice koji was made with each strains, and its saccharogenic activity, dextrogenic activity, proteolytic activity, acid Producing ability, browning reaction and flavor were tested. Among 31 strains of isolates, 10 strains were Identified as Asp nwamori var. kawachii, 18 strains as Asp. oryzae, 3 strains as Asp. usamii mkt. shirousamii. The koji-starters made in Korea were composed of single species of koji-mold with same strain, but those made in Japan were composed of the mixture of different two species or the mixture of different 2 ∼4 strains in same species. Judging from amylolytic and proteolytic ability by species, Asp. awamori var. kawachii H1, I1 and 11, Asp. owsae J2, L2, M2, P3 and P4, and Asp. usamii writ. shirousamii S1 were better than the others. Mold strains isolated from Korean koji-starters were much lower in amylolytic or proteolytic activity than those from Japanese koji-starters. The typical characteristics for the 3 species of koji-molds were that Asp. awamori var. kawachii was strong in acid producing ability, but week in amylolytic and proteolytic ability, that Asp. owzae had strong amylolytic activity and good aroma, but produced little amount of acid, and that Asp. usamii mut. shirousamii had strong Proteolytic activity but some off-flavor.

• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.161-173
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• 2005

This study was carried out to clarify the effects of antifungal bacterial strains isolated from the greenhouse soil grown strawberry plants on the growth inhibition of plant pathogen, gray mold (Botrytis cinerea) infected in strawberry plants in Damyang and Jangheung districts. Antagonistic bacterial strains were isolated and investigated into the antagonistic activity against gray mold. Screened ten bacterial strains which strongly inhibited Botrytis cinerea were isolated from the greenhouse grown strawberry plants, and the best antifungal microorganism designated as SB 143 was finally selected. Antifungal bacterial strain SB 143 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. SB 143 showed 59.4% of antifungal activity against Botrytis cinerea. By the bacterialization of culture broth and heated filtrates of culture broth, Bacillus sp. SB 143 showed 93.1% and 32.1% of antagonistic activity against Botrytis cinerea.

• Korean Journal of Microbiology
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• v.18 no.4
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• pp.188-192
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• 1980

In search of dextran-hydrolyzing enzymes, approximately 500 strains of molds were checked for their ability to produce extracellular dextranase. Seven strains capable of producing dextranase were screened, and among them, one strain belonging to Aspergillus genus showed greater activity than the other. The strain was identified to be Aspergillus ustus and the most suitable culture conditions for the enzyme production were determined.

• Research in Plant Disease
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• v.25 no.1
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• pp.16-21
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• 2019

Botrytis cinerea is the pathogen for a gray mold generating problems during the cultivation and transportation of roses. But there is little information about the difference of the symptom severity caused by gray mold on rose varieties and pathogen strains. 16 strains were collected from the rose cultivation area to confirm the degree of disease occurrence against strains and each variety. Collected 16 strains were identified based on the sequences analysis of ITS region of ribosomal DNA by using specific primers. The sequence analysis was performed by comparing the sequences to find a difference. To confirm the difference in disease occurrence for each strains, the difference was classified from 0 to 5 stages using charmant variety as a control. The data was confirmed through Kruskal-Wallis ANOVA. The result showed the significant difference in the pathogenicity caused by strains. WNG6_5 showed the lowest pathogenicity with 0.24 and WNG6_3 showed the highest with 3.20. The difference between two strains were almost 3.0. In addition, nine varieties of roses were more investigated with three strains such as the strains of WNG6_5, Hwa_1, and WNG6_3. The result showed that the Love Letter variety showed resistance and the Ice Bear variety was sensitive to three strains. Taken together, this study showed the significant difference by the interactions of rose varieties and gray mold strains.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.764-772
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• 1999

To develop an enzyme-linked immunosorbent assay (ELISA) for detecting mold, we produced anti-mold polyclonal antibodies by immunizing extracellular polysaccharide (EPS) of Aspergillus flavus or Penicillium citrinum in rabbits subcutaneously. Using the purified antibody (Ab) and Ab-HRP conjugate, a sandwich ELISA for EPS was established. The standard curve of the ELISA showed the detection limit for P citrinum EPS to be $0.003{\;}\mu\textrm{g}/ml$. The cross-reactivities of the anti-P citrinum EPS Ab toward components of P citrinum such as EPS, liquid, and solid culture mycelium were 100, 10.5, and 0.58%, respectively, and those toward components of A. flavus such as EPS, liquid and solid culture mycelium, and spore were 300, 0.67, 0.29, and 0%, respectively. When the reactivities toward culture broths of 59 mold strains were tested by the sandwich ELISA, most of the Aspergillus (16 of 18) and Penicillium (14 of 16) strains along with one of the two Cladosporium strains gave positive signals in the culture broths even when diluted 1,000 fold, while the rest of species such as Fusarium, Absidia, Alternaria, and Candida gave negative signals. When the water extracts of 30 corn samples were analyzed by the sandwich ELISA, the EPS in the com could be detected in the concentration range of $0.1-1.6{\;}\mu\textrm{g}/g$.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.98.1-98
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• 2003

Antagonistic effect of bacterial strains isolated from phylloplane of strawberry plants grown In greenhouse was tested on Botrytis cinerea Among the promising bacterial strains, Bacillus sp. S1-0210 showed highest inhibition of mycelial growth of B. cinerea and a broad spectrum of antifungal activities against many plant pathogenic fungi in vitro. Bacillus sp. S1-0210 was identified as Bacillus subtilis based on the analysis of 185 rDNA as well as its biochemical characteristics. Application of wettable powder formulation of B. subtiiis S1-0210 significantly reduced the incidence of gray mold on trawberry fruits during storage. Results showed that treatment of B. subtilis S1-0210 decreased the incidence of gray mold by 4.8％ whereas the incidence in control was 77.9％, indicating that the formulation of B. subtilis S1-0210 will be practically applied on strawberry fruits as a biocontrol agent of gray mold during storage.

• Mycobiology
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• v.38 no.2
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• pp.122-127
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• 2010

Different strains of mold were screened for the production of high quality Korean traditional rice wine with anti-hypertension and good acceptability. We isolated 867 nuruk mold strains and selected 24 for further study based on measurement of amylase activity. Among them, mold No. 17 showed high ethanol production upon fermentation with Saccharomyces cerevisiae as well as anti-hypertensive properties. The No. 17 strain was therefore selected as the functional mold and later identified as Rhizopus stolonifer based on molecular biological characteristics. Optimal fermentation conditions for the brewing of anti-hypertensive traditional rice wine comprised the addition of R. stolonifer No. 17 koji at a concentration of 35 sp/g and a fermentation period of 10 days at $25^{\circ}C$ using S. cerevisiae.

• The Plant Pathology Journal
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• v.35 no.5
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• pp.425-436
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• 2019

Botrytis cinerea, a major phytopathogenic fungus, has been reported to infect more than 200 crop species worldwide, and it causes massive losses in yield. The aim of this study was to evaluate the inhibitory abilities and effects of Bacillus amyloliquefaciens RS-25, Bacillus licheniformis MG-4, Bacillus subtilis Z-14, and Bacillus subtilis Pnf-4 and their culture filtrates and extracts against the gray mold caused by B. cinerea on postharvest tomato, strawberry, and grapefruit. The results revealed that the cells of Z-14, culture filtrate of RS-25, and cells of Z-14 showed the strongest biocontrol activity against the gray mold on the strawberry, grape, and tomato fruit, respectively. All the strains produced volatile organic compounds (VOCs), and the VOCs of Pnf-4 displayed the highest inhibition values. Based on headspace solid-phase microextraction in combination with gas chromatography-mass spectrometry, esters accounted for the largest percentage of the VOCs produced by RS-25, MG-4, Z-14, and Pnf-4 (36.80%, 29.58%, 30.78%, and 36.26%, respectively). All the strains showed potent cellulase and protease activities, but no chitinase activity. RS-25, Z-14, and MG-4, but not Pnf-4, grew on chrome azurol S agar, and an orange halo was formed around the colonies. All the strains showed biofilm formation, fruit colonization, and lipopeptide production, which may be the main modes of action of the antagonists against B. cinerea on the fruit. This study provides the basis for developing natural biocontrol agents against the gray mold caused by B. cinerea on postharvest fruit.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.251-254
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• 2011

Botrytis cinerea infects stems and leaves of greenhouse tomatoes and can cause serious economic losses. This study was conducted to develop environment-friendly control method against tomato gray mold. Antagonistic microorganisms (bacteria) were screened for control activity against Botrytis cinerea, both in vitro and in vivo, using stem sections. One hundred bacterial strains were isolated from the rhizospheric soil of various plants including tomato. These strains were screened for growth inhibition of Botrytis cinerea on agar plate by the dual culture and thirty strains showing strongly inhibitory effect against the pathogen were selected first. Among thirty strains, JB 5-12, JB 22-2, JB 22-3, U 4-8 and U46-6 reduced significantly disease incidence, when applied simultaneously with the pathogen. These results suggested that five antagonistic bacteria strains selected have the potential to control tomato gray mold in organic farming.