• The Korean Journal of Mycology
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• v.20 no.3
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• pp.259-268
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• 1992

Fifty-three actinomycetes antagonistic to Phytophthora capsici and Magnaporthe grisea were isolated from rhizosphere soils in six pepper-growing areas and ashore soils. Thirty-two antagonistic actinomycetes, showing inhibition zone larger than 5 mm, were classified into 20 groups according to their colony morphology and color. The antagonistic activity against P. capsici greatly varied, which showed inhibition zone sizes in the ranges from 5.7 to 17.5 mm on V-8 juice agar and from 2.5 to 17 mm on tryptic soy agar. The antagonistic activity of some actinomycetes tested was remarkably different between the two test media. The antagonists showed a relatively broad antifungal spectrum, but their antibacterial activity was negligible, except for Pseudomonas solanacearum. Butanol extracts of culture filtrates from antagonistic actinomycetes inhibited mycelial growth of P. capsici and M. grisea, thereby confirming strongly antibiotic production in culture. Culture filtrates of some antagonistic actinomycetes completely inhibited Phytophthora blight in pepper plants.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.67-73
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• 1996

This study was conducted to determine the effect of treatment with the plant-growth-promoting bacteria on the growth of red pepper(Capsicum annuum L.).The eight plant-growth-promoting bacteria were isolated from the humic soil in the forest region. The isolated bacteria(IB) was identified by the method of the biochemical test(API kit) and the composition of the fatty acid(MIDI system).The IBs were inoculated by spray of 17ml at 72 cell tray filled with peatmoss every week. respectively, with mixed liquid eulture of eight strains. The IBs were identified as Micrococcus sp.. Bacillus subtilis. Enterobacter agglomerans, Bacillus megaterium, Pseudomonas putida. Pseudomonas fluorescens, Xanthomonas maltophilia and Staphylococcus xylosus by API kit and MIDI system. The plant height number of leaves and leaf length of red pepper grown on peatmoss treated with the IB were better than those of nontreatment at the 10th day after inoculation.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.11-18
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• 2020

Bacteria of the genus Enterococcus are of importance in food fermentations as well as their use as probiotics in humans and livestock. However, they are also important nosocomial pathogens that cause infections. Some strains are resistant to multiple antibiotics and possess virulence factors. The role of Enterococcus species in disease has raised issues on their safety for use in foods or as probiotics. First, this review summarized the positive and negative traits of Enterococcus spp. to illustrate the controversial nature of this bacterial genus and discussed the current genomic approaches can eliminate pathogenic strains. Then, this review examined the current status of starter development for traditional food fermentations and the regulation on the approval of novel food microorganisms in Korea to point out problems in the regulation. Based on the conclusions from the studies on Enterococcus spp., we suggested the direction of safety assessment of novel food microorganisms in Korea.

• Research in Plant Disease
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• v.12 no.3
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• pp.267-271
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• 2006

Botrytis cinerea Pers. was found to be highly virulent to the grapevine plant, especially in greenhouse condition. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. Of the 83 isolates of Pseudomonas spp., a bacterial strain P84, isolated from tomato rhizosphere, was shown to suppress a wide range of phytopathogenic fungi in vitro. The isolate was identified as Pseudomonas putida on the basis of its bacteriological and genetic characteristics. The P. putida P84 strain carry the phlD gene for 2,4-diacetylphloroglucinol biosynthesis and may produce the antibiotics as an antagonistic mechanism involved in biocontrol. The antagonistic activity of the bacterium has a promising implication for its use as a biocontrol agent to control grapevine gray mold.

• KSBB Journal
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• v.11 no.1
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• pp.92-98
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• 1996

A chitinase-producing bacterium was isolated from seashore mud around Beobseongpo in Chunnam province by selective enrichment culture, and among it, one isolate which was the best in producing of chitinase was selected. Nutrient or MacConkey medium was confirmed with secreting of prodigiosin pigment by Serratia sp. JM, and it was performed by the production of clear zone on medium containing chitin. Serratia sp. JM was almost same compared with Serratia marcescens ATCC 27117 in respect of its morphological, physiological and biochemical characteristics except succinic, urea and pyruvic acid. Serratia sp. JM was resistant to tetracycline but was not resistant to kanamycin and chloramphenicol. The optimal temperature and pH for the production of chitinase from Serratia sp. JM were $30^{\circ}C$ and 7.5, respectively. Production of chitinase and pH in the medium increased until the cultivation of 120 hours, but after 120 hours, they were decreased due to the acetic acid accumulated from degradation of chitin by Serratia sp. JM.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.258-265
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• 2012

Bacterial strains isolated from diseased red pepper fruits showed inhibitory effect on mycelial growth and spore germination of Colletotrichum gloeosporioides. The bacterium was identified as Paenibacillus sp. based on its physiological, biochemical characteristics and MicroLog analysis and named Paenibacillus sp. IUB225-08. The bacterium showed the highest level of antifungal activity C. gloeosporioides when cultured at $25^{\circ}C$ for 60 hrs in LB broth with initial pH of 7.0. The butanol fraction from culture extract of Paenibacillus sp. IUB225-08 effectively inhibited the mycelial growth and spore germination of C. gloeosporioides than any other agricultural chemicals tested. Pepper fruits and seeds treated with spores of C. gloeosporioides showed symptoms, while those treated with the culture extract and C. gloeosporioides together did not show any symptoms. Therefore, the culture extract of Paenibacillus sp. IUB225-08 have a potential for biocontrol agent of red pepper anthracnose.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.395-400
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• 1992

A novel strain of HSL613 producing a large amount of cholesterol oxidase as an extra~ cellular enzyme was isolated from soil samples. Experiments were carried out to optimize the condition of cholesterol oxidase production using HSL613 strain. This microorganism was shown to give the maximum yield f)f cholesterol oxidase in the medium containing 2% glucose, 2% yeast extract, 0.2% $K_2HP0_4$, 0.1% NaCl. 0.005% $CaCl_22H_2O, 0.001% $FeSO_47H_20$. The optimum temperature was $30^{\circ}C$ and the enzyme production reached a maximum level at 144 hours of cultivation (10.3$\mu$/ml).

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.924-927
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• 2003

This study was conducted to investigate the application of bifidobacteria on kimchi. Among several Bifidobacterium species, we selected Bifidobacterium lactis (DSM 10140), which is resistant to oxygen, acid and salt. Bifidobacterium lactis was cultured in a supplemented deMan, Rogosa and Sharpe (SMRS) medium under aerobic conditions. Its acid-tolerance and salt-tolerance were pH 3.0 and 3.5% (NaCl), respectively. The viability of Bifidobacterium lactis added to kimchi was confirmed by PCR, using specific primers on Bifidobacterium lactis. In sensory evaluation, kimchi containing Bifidobacterium lactis showed similar scores in overall acceptability with the control kimchi. Consequently, these results showed that it would be possible to prepare functional kimchi using Bifidobacterium.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.213-216
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• 2011

Gray mold symptoms were frequently observed on green twigs, blossoms, leaves, and fruits of blueberry trees grown in greenhouses in Cheongyang, Dangjin, Daejeon, and Jeju during disease survey in eight locations of Korea from 2007 to 2010. The disease symptoms were not observed in the fields of the other locations investigated. The disease incidence ranged 1~30% in the greenhouses investigated. A total of 27 single spore isolates of Botrytis species were obtained from the gray mold symptoms, and all the isolates were identified as Botrytis cinerea based on their morphological and cultural characteristics. Four isolates of the fungus were tested for pathogenicity to leaves of four varieties of blueberry trees by artificial inoculation with conidial suspensions. All the tested isolates caused gray mold symptoms on the leaves, which were similar to those observed in the greenhouses. This is the first report that B. cinerea causes gray mold of blueberry trees grown in greenhouses in Korea.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.191-195
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• 2007

Four bacteria producing viscous exopolysaccharides (EPSs) were isolated from Korean fermented vegetables (Cucumber kimchi, Young radish kimchi, Green onion kimchi) using a selection medium intended for isolating bacteria with tannin-degrading activity. They were identified phylogenetically by 16S rDNA sequence analysis and found to be very close to Enterobacter cowan ii, Escherichia senegalensis, Enterobacter asburiae, and Enterobacter ludwigii. Strain CK31, the most efficient EPS-producer, produced a heteropolysaccharide with an approximate molecular weight of 420 kDa. The neutral sugar fraction of the EPS was composed of rhamnose, fucose, arabinose, mannose, galactose, and glucose.