• The Korean Journal of Mycology
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• v.10 no.1
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• pp.33-39
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• 1982

Carpophores of ten Korean strains of Lentinus edodes (Berk.) Singer, an antitumor polysaccharide producing fungus, were extracted with 0.1N NaOH solution. The extracts were dialized for seven days in distilled water and lyophilized to produce crude polysaccharide powders. Thus obtained crude polysaccharide samples were assayed for sugar contents by colorimetric method with anthrone reagent. Among ten strains examined Lentinus edododes-DMC7 was found to be the richest strain in polysaccharide content of carpophores. By shake culture experiment for biomass production, L. edodes-DMC7 was found to be the second most productive strain among seven strains examined. Cultural characteristics of L. edodes-DMC7 were investigated by shake culture method. The best result was obtained when L. edodes-DMC7 was cultured in the medium containing glucose 8g, starch 80g, yeast extract 12g, $KH_2PO_4\;0.87g,\;MgSO_4{\cdot}7H_2O\;O.5g,\;CaCl_2\;0.3g,\;FeSO_4{\cdot}7H_2O\;10mg\;ZnSO_4{\cdot}7H_2O\;4mg,\;CuSO_4{\cdot}5H_2O\;lmg,\;MnCl_2{\cdot}4H_2O\;7mg\;per\;11\;at\;28^{\circ}C$, 180 rpm, for 12 days. Thus thirty-three grams of dry mycelia was obtained per one liter of medium.

• Research in Plant Disease
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• v.30 no.1
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• pp.66-77
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• 2024

Black wood ear mushroom (Auricularia auricula-judae) is one of the most economically important mushrooms in China, Japan, and Korea. The cultivation of wood ear mushrooms on artificial substrates is more efficient in terms of time and cost compared with their natural growth on trees. However, if the substrate cultivation is infected by fast-growing fungi, the relatively slow-growing ear mushroom will be outcompeted, leading to economic losses. In this study, we investigated the competitive fungal isolates from substrates infected with fast-growing fungi for the cultivation of ear mushrooms in Jangheung and Sunchon, Korea. We collected 54 isolates and identified them by sequencing their internal transcribed spacer region with morphological identification. Among the isolates, the dominant isolates were Trichoderma spp. (92.6%), Penicillium spp. (5.6%), and Talaromyces sp. (1.8%). To find an appropriate eco-friendly biocontrol agent, we used five Streptomyces spp. and Benomyl, as controls against Trichoderma spp. and Penicillium spp. Among the six Streptomyces spp., Streptomyces sp. JC203-3 effectively controlled the fungi Trichoderma spp. and Penicillium spp., which pose a significant problem for the substrates of black wood ear mushrooms. This result indicated that this Streptomyces sp. JC203-3 can be used as biocontrol agents to protect against Trichoderma and Penicillium spp.

• Journal of Life Science
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• v.21 no.10
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• pp.1481-1486
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• 2011

Spent mushroom substrate (SMS) is a by-product remained after a crop of mushrooms. About seven thermophilic strains were isolated from SMS (Flammulina velvtipes). Among them, one isolate, designated UJ03, showed the antifungal activity against Aspergillus flavus and Aspergillus ochraceous producing mycotoxin on PDA medium, potentially. The strain UJ03 produced cellulase and xylanase as extracellular hydrolases. The strain UJ03 was identified as a member of the genus Bacillus by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that strain UJ03 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus amyloliquefaciens with sequence similarity of 98.9%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, strain UJ03 was classified within the genus Bacillus, for which the name Bacillus sp. UJ03 is proposed. The antifungal compound from Bacillus sp. UJ03 was similar to lipopeptide iturin A of Bacillus sp.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.187-192
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• 1986

The inoculation effect of the highly nitrogen fixing strains of R. japonicum were tested in the 3 kinds of soil with different cultural history onto Gycine max cv. Jang-yeob. The nodulation and nitrogen fixation activity in 3 test soils all showed the great increase in inoculated group compared to the non-inoculated group. The plant dry weight of the in-oculated groups were increased about 10% than that of the non-inoculated groups. The numerical index of the increase in total nitrogen fixation activity were 238% in the pre-cultivated, 266% in the immatured and 157% in the matured soil and these results suggested the clear effect of inoculation. Among the strains tested, R. japonicum R214 and Rl38 showed the excellent inoculation effect.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.226-233
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• 1994

Three hundred and one cellulolytic bacterial were isolated from the 148 screening sources such as decomposed wood, soil, compost and leaf mold. Among them, strain KL-6 was found to have the highest of cellulase activity, and identified as species belonged to the genus Cellulomonas. Strain KL-6 was decompose up to 90% of the filter paper (whatman No. 1) substrate within 50 hours, and showed the colony halo formation (11 cm). The activities of CMCase (67 unit/ml), FPase (70 unit/ml) and ${\beta}-glucosidase$ (0.68 unit/ml) were obtained when this strain was cultured for 50 hrs at $30^{\circ}C$. Glucose was not found in detectable amounts at the FP medium. The optimum composition of nutrient medium for the cell growth by strain KL-6 was sucrose 0.5%, yeast extract 0.1%, $(NH_4)_2HPO_4\;0.1%$, $K_2HPO_4\;0.1%$, $MgSO_4{\cdot}7H_2O\;0.01%$, $CaCl_2\; 0.01%$, NaCl 0.6%, $CaCO_3\;0.1%$ and the optimum pH and temperature were 7.0 and $30^{\circ}C$, respectively.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.224-230
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• 1978

Heat resistant putrefactive microorganisms causing spoilage of canned and processed foods were surveyed in the compost on mushroom growing bed, casing soil, raw mushrooms and canned products before sterilization at canneries located at 8 places including Buyo in Chung-Cheung-Do and monitored the total count and spore formers from the sample taken. The 9 strains of most severe heat resistant among the selected 140 spore formers were selected and determined D and Z value by TDT method. The most strong heat resistant strain was No. F-10, facultative thermophile, which was isolated from raw mushroom in Buyo area and it's Z value was $21.1^{\circ}F$ (M/15 phosphate buffer solution) and $D^{250}$ was 6.6 min.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.62-67
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• 2016

Hydrolytic enzyme activities, including those of ${\beta}$-glucosidase, ${\beta}$-glucuronidase, ${\beta}$-xylosidase, ${\beta}$-galactosidase, ${\beta}$-arabinofuranosidase, ${\beta}$-arabinosidase, and ${\beta}$-arabinopyranosidase, which are useful for bioconversion, were explored in lactic acid bacteria isolated from Korean traditional fermented foods. Nine bacterial strains were selected for the fermentation of green tea extract prepared by supercritical fluid extraction. Changes in the concentrations of catechin, epicatechin, epicatechin gallate, epigallocatechin, and epigallocatechin-3-gallate in green tea extract were investigated after fermentation by the selected lactic acid bacteria strains. The strain Leuconostoc mesenteroides MBE1424, which showed the highest ${\beta}$-glucuronidase enzyme activity among the tested bacterial strains, increased the epigallocatechin content of the green tea extract by 60%. In addition, L. mesenteroides MBE1424 was more resistant than the control strain at high temperature and showed a maximum specific growth rate at $40^{\circ}C$. L. mesenteroides MBE1424 was presumed to have an enzyme system containing ${\beta}$-glucuronidase with utility in the bioconversion of green tea extract.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.210-215
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• 2002

A bacterium degrading soy protein was isolated from Korean traditional fermented foods. The isolated strain was identified as Bacillus subtilis, and named as B. subtilis EB464. The optimum pH and temperature of the protease produced by 5. subtilis EB464 were pH 9.0 and $50^{\circ}C$, respectively. The protease was stable in the range of pH 6~10 and below $40^{\circ}C$. The content of water-soluble protein and free amino acid of the medium were increased from 4.2% to 20.6% and ken 1.9% to 22.0%, respectively, by solid-state fermentation of soybean meal with B. subtilis EB464 for 72 h.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.219-225
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• 2009

A bacterial strain, JE-34, producing a high concentration of red pigment was isolated from a sediment in East China Sea. It was identified as Zooshikella sp. JE-34 based on the 16S rRNA gene sequence analysis. The red pigment was purified by solvent extraction and HPLC was identified as prodigiosin-like compound. Nutritional and cultural conditions were optimized for the production of prodigiosin-like pigment in the flask level. Optimal culture conditions were at initial medium pH $6.0{\sim}7.0$, $30^{\circ}C$ and 4 days incubation. For carbon and, nitrogen sources were soluble starch and malt extract.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.320-329
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• 1997

Botrytis cinerea isolates obtained from infected plants of cucumber, tomato, and strawberry were divided into three groups (sporing, sclerotial, and mycelial types). Of which sclerotial types were the major group. There were no correlations between morphological phenotypes and responses to benzimidazole and dicarboximide fungicides. External structure of conidia of three phenotypes by scanning electron microscope was the same with verrucose surface. Mycelial type was the most virulent on fruits of eggplants. Comparative tests were carried out to examine correlations between the virulence and production of fungal enzymes such as phenol oxidases, pectin methyl esterases (PME), amylases, cellulases, ureases, ${\beta}-glucosidases$, and proteinases. There was no correlation among the phenotypes in production of phenol oxidases and ${\beta}-glucosidases$. However, there were significantly different from each other in PME, amylase, cellulase, urease, and protease activity.