• Korean Journal of Microbiology
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• v.52 no.4
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• pp.471-481
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• 2016

The primary objective of this study was to investigate the effects of the bacteriocin-producing heterofermentative lactic acid bacteria (LAB) and acid-resistant yeast isolated from Mukeunji, a Korean ripened kimchi on shelf-life extension and quality improvement of sourdough. According to gene sequence analysis the heterofermentative LAB that showed the antimicrobial activity against bread-spoilage Bacillus strains were identified as Leuconostoc mesenteroides LAS112, Lactobacillus brevis LAS129, and L. mesenteroides subsp. dextranicum LAB137. In addition, the yeasts that were able to grow at acidic pH were identified as Pichia membranifaciens YS05, Pichia fermentans YS19, and Pichia anomala YS26. During sourdough fermentation the levels of acetic acid and bacteriocin produced by L. brevis LAS129 strain were higher than those of L. mesenteroides LAS112 and L. mesenteroides subsp. dextranicum LAS 137 strains, whereas LAS112 strain produced the highest levels of lactic acid. The maximum bacteriocin activity (640 AU/g) against Bacillus subtilis ATCC 35421 was obtained in sourdough fermented by mixed culture of L. brevis LAS129 and P. membranifaciens YS05 or P. anomala YS26. After 24 h of fermentation at $30^{\circ}C$, the viable cell counts of LAS129 ($10^9CFU/g$) in sourdough were higher than those of the YS05 or YS26 ($10^7CFU/g$). Meanwhile, the viable cells of bread-spoilage strain in sourdough fermented with these strains were significantly (P < 0.05) lower than the control group.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.523-531
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• 2020

This study focused on the isolation and characterization of wild yeasts in Korea. The yeasts were identified by phylogenetically analyzing the D1/D2 domains of the 26S rDNA regions. Consequently, we identified seven strains, NNIBRFG856, NNIBRFG3732, NNIBRFG3734, NNIBRFG3738, NNIBRFG3739, NNIBRFG5497, and NNIBRFG6049, which were confirmed to be Kabatiella microsticta, Pichia membranifaciens, Candida vartiovaarae, Candida sake, Debaryomyces hansenii, Candida railenensis, and Schwanniomyces polymorphus, respectively, all of them being new in Korea. Morphological and cultural characteristics of these yeast species were investigated. None of the strains formed ascospores or pseudomycelia. Moreover, these yeasts grew in a pH range of 4-8. NNIBRFG3732, NNIBRFG3738, NNIBRFG3739, NNIBRFG5497, and NNIBRFG6049 were halotolerant or halophilic, and NNIBRFG3732, NNIBRFG3734, and NNIBRFG6049 grew in vitamin-free medium. NNIBRFG3732, NIBRFG3739, and NNIBRFG6049 grew at 35 ℃, but not at 40 ℃.

• KSBB Journal
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• v.23 no.2
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• pp.118-124
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• 2008

Three kinds of bacteria that influence Kimchi fermentation, Lactobacillus plantarium for acidity, Leuconostoc mesenteroides for ripening Kimchi, and Pichia membranifaciens for decreasing Kimchi quality, were regulated by natural products including Theae folium, Taraxacum coreanum, Brassica juncea, Astragali radix, Gynostemma pentaphyllum, Camellia japonica, Agaricus blazei, and Cordyceps militaris. The common prescription combined T. folium, T. coreanum and C. militaris and simultaneously regulated these 3 bacteria as follows: the growth of L. plantarium and P. membranifaciens were inhibited and L. mesenteroides was promoted. The most effective mixing ratio was T. folium: T. coreanum: C. militaris = 3:2:1. With this new prescription, deep flavor, extended preservation, and a special taste are expected in the Kimchi due to these natural products.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.199-204
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• 2009

Three plant growth-promoting yeasts and two rhizobacteria were tested for controlling tomato wilt caused by Fusarium oxysporum f. sp. lycopersici under green-house and field conditions. Under greenhouse and field conditions, all treatments were significantly reduced disease severity of tomato wilt relative to the infected control. The highest disease reductions in pots (75.0, 67.4%) and field (52.5, 42.4%) were achieved by Azospirillum brasilense and Bacillus subtilis compared to infected control. Under field condition all treatments produced the highest tomato yield compared to the control plants inoculated with the pathogen.