• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.350-357
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• 1998

A total of 12 strains of fluorescent Pseudomonas isolated from the cultivated mushrooms such as Agaricus bisporus and Pleurotus ostreatus were collected. They consisted of pathogenic Pseudomonas spp. and epiphytic Pseudomonas spp. of the cultivated mushroom. To analyze the phylogenetic relationship of these strains, ITS I region, the 16S-23S intergenic spacer region in the ribosomal RNA (rRNA) operon, was cloned and sequenced. The spacer regions of these strains were 495∼527 nucleotides in length and contained the genes encoding isoleucine-tRNA (tRNAIle) and alanine-tRNA (tRNAAla). The reciprocal homologies of each ITS I sequence among these strains were in the range of 84.2%∼98.8%. According to the analysis of ITS I sequences, the fluorescent Pseudomonas spp. were phylogenetically classified into three clusters. Cluster I consisted of Pseudomonas fluorescens, P. tolaasii, P. gingeri’, and P.‘reactans’(WLRO). Cluster II comprised Pseudomonas fluorescens biovar C and F. Cluster III composed P. agarici. Cluster I and II could be classified into P. fluorescens complex. P. agarici formed an independent taxon clearly separable from P. florescens complex.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.246-254
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• 2018

Enzyme fermentation is a type of food processing technique generally used to improve the biological activities of food and herbal medicines. In this study, a Syzygii Flos (clove) extract was fermented using laccase derived from Trametes versicolor (LTV). The fermented clove extract showed greater neuroprotective effects against glutamate toxicity on HT22 than the non-fermented extract did. HPLC analysis revealed that the eugenol (1) and dehydrodieugenol (2) contents had decreased and increased, respectively, after fermentation. The content of 2 peaked at 1 h after fermentation to $103.50{\pm}8.20mg/g_{ex}$ (not detected at zero time), while that of 1 decreased to $79.54{\pm}4.77mg/g_{ex}$ ($185.41{\pm}10.16mg/g_{ex}$ at zero time). Compound 2 demonstrated promising HT22 neuroprotective properties with inhibition of $Ca^{2+}$ influx, the overproduction of intracellular reactive oxygen species, and lipid peroxidation. In addition, LTV showed the best fermentation efficacy compared with laccases derived from Pleurotus ostreatus and Rhus vernicifera.

• Mycobiology
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• v.38 no.4
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• pp.310-315
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• 2010

Agrocybe aegerita is an important mushroom cultivated in Korea, with good feel and a peculiar fragrance. A. aegerita can be cultivated throughout the year using culture bottles but is more susceptible to contamination than other mushrooms. Twenty-two pathogens were isolated from the fruiting bodies and compost of A. aegerita, and seven isolates were isolated from Pleurotus ostreatus to compare with the A. aegerita isolates, collected from Gimje, Iksan, Gunsan of Chonbuk, and Chilgok of Gyeongbuk Province in 2009. These isolates were identified based on morphological and molecular characteristics. Of the 29 isolates, 26 were identified as Trichoderma spp. and the remaining three were Aspergillus spp., Mucor spp., and Penicillium spp. A phylogenetic analysis revealed that the 26 isolates of Trichoderma were divided into four taxa, namely T. harzianum, T. pleuroticola, T. longibrachiatum, and T. atroviride. Among the Trichoderma spp., 16 isolates (55.2%) were identified as T. harzianum, six as T. pleuroticola (20.7%), two as T. longibrachiatum, and the remaining two were T. atroviride.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.29-33
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• 1984

Chemical composition and condition of acid hydrolysis of waste composts during the cultivation of oyster mushroom (Pleurotus ostreatus) were determined. Ash content of composts increased while organic matter content decreased as the cultivation progressed. More than 90% of mushroom was produced from the first and second cropping period. An optimum condition for acid hydrolysis was at 2.0% $H_{2}SO_{4},\;1.5kg/cm^{2}$ vapor pressure for 30min and 20times (acid/compost). Formation of furfural in acid hydrolysis increased remarkably as acid concentration increased.

• Journal of Agricultural Extension & Community Development
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• v.6 no.2
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• pp.141-147
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• 1999

This experiments were carried out to development low-priced mushroom culture media, and the results were as follows : Mycerial growth and density of Pleurotus ostreatus in the culture media of 40% of yellow soil, upland soil and lowland soil(each and all) added 60% sawdust and rice bran(80:20, %, v/v) were 89, 88, 68mm/10days in that order. Lentinus edodes were in the media of $40{\sim}50%$ of that added 60% sawdust and rice bran(80:20, %, v/v) were 74, 71, 68mm/10days. Ganoderma lucidum were in the media of $40{\sim}50%$ of that added 60% sawdust and rice bran(80:20, %, v/v) were 98, 94, 89mm/10days in that order.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.986-993
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• 2002

Mushroom mycelia-cultured traditional meju (MTM) was prepared by inoculating 10% submerged-liquid culture of mushroom strains to five holes (1$\times$3 cm) per side of the traditionally-fermented meiu (10$\times$10$\times$10cm), followed by incubating additional 4 weeks at $25^{\circ}C$. Mushroom strains used were Neutari (Pleurotus ostreatus, PO), Yeongji (Ganoderma lucidum, GL), Synryeong (Agaricus blazei, AB), Ypsae (Grifola frondosa, GF), Pyogo(Lentinus edodes, PE), Dongchunghacho (Paecilomyces japonicus, PJ) and Sanghwang (Phellinus linteus PL). All MTMs showed an enhanced anticarcinogenicity against S-180 cell-induced mouse ascites cancer antimutagenicity against aflatoxin B$_1$ (AFB$_1$) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), and sensory qualities, relative to control meju. Such positive effects of MTM prepared with Sanghwang, Yeongji, or Synryeong were superior to those of MTM with Ypsae, Pyogo, Dongchunghacho, or Neutari.

• Journal of Mushroom
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• v.8 no.2
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• pp.41-50
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• 2010

Mycoviruses have been found in many fungal species including mushrooms. Double-stranded (ds) RNA genomes were common type in mycoviruses, but single-stranded (ss) RNA mycoviruses were also reported in some fungal species. Sequencing analysis using cDNA cloning experiments revealed that mycoviruses can be classified into several different virus families such as Totiviridae, Hypoviridae, Partitiviridae and Barnaviridae etc. Because the nucleotide sequence data that are available in these days are very limited in a number of mycoviruses, the existence of more diverse viral groups in fungi are currently expected. In this review, we selected four different fungal groups, which were considered as the model systems for mycovirus related studies in both plant pathogenic fungi and edible mushroom species, and discussed about their molecular characteristics of diverse mycoviruses. The plant pathogenic fungi introduced here were Cryphonectria parasitica and Helminthosporium victoriae and the edible mushroom species were Agaricus bisporus and Pleurotus ostreatus.

• Journal of the Korean Wood Science and Technology
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• v.14 no.3
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• pp.36-42
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• 1986

The production media and the enzymatic charateristics of laccase from Flammulina velutipes were investigated. The activity of laccase during incubation reached to the maximum at the 40 days of incubation in the case of Barley straw medium. The maximum laccase activity in Barley straw medium was 5 and 16 times higher than those in Onion basic and Sawdust media, respectively. The laccase from Flammulina velutipes has the optimum pH of 6.6 and showed to be stable at relatively broad pH range. 4.5-9.5. Temperature stability showed that above 96% activity could be preserved after holding at 40$^{\circ}C$ for 40 minutes. At the above 70$^{\circ}C$, the laccase activity decreased very rapidly. The Km value of the laccase was estimated to be 28.0 mM which is much higher than that of the laccase from Pleurotus ostreatus. Organic solvents for precipitiation of the enzyme did not inactivation the laccase. Sodium azide which was added for preventing microbial deterioration affected significantly the inactivation of laccase, but this activity was recovered completely by precipitating the enzyme with acetone.

• Journal of Mushroom
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• v.6 no.3_4
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• pp.126-130
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• 2008

The combination ratio of oyster mushroom cultivation supplements have used poplar sawdust(PS) 50% : beet pulp(BP) 30% : cotton seeds meal(CS) 20%. we substituted cotton seeds meal and beet pulp for food by-product dried wastes(DW) 10, 20. 30% respectively. In case of mixing with DW 10% except from BP, mycelial growth was inhibited a little, but mycelial density was accelerated. The more DW contents increase, the more mycelial growth was inhibited, but mycelial growth was accelerated a little, respectively. In case of mixing with DW except from CS, mycelial growth was similar to control almost. In case of mixing with DW except from CS and BP, mycelial growth was inhibited remarkably. CHUNCHU variety developed resistance to developed than SUHAN variety.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2064-2070
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• 2018

Pseudomonas tolaasii 6264 is a representative strain that causes bacterial blotch disease on the cultivated oyster mushroom, Pleurotus ostreatus. Bacteriophages are able to sterilize the pathogenic P. tolaasii strains, and therefore, they can be applied in creating disease-free mushroom cultivation farms, through a method known as "phage therapy". For successful phage therapy, the characterization of phage-resistant strains is necessary, since they are frequently induced from the original pathogenic bacteria in the presence of phages. When 10 different phages were incubated with P. tolaasii 6264, their corresponding phage-resistant strains were obtained. In this study, changes in pathogenic, genetic, and biochemical characteristics as well as the acquired phage resistance of these strains were investigated. In the phylogenetic analyses, all phage-resistant strains were identical to the original parent strain based on the sequence comparison of 16S rRNA genes. When various phage-resistant strains were examined by three different methods, pitting test, white line test, and hemolytic activity, they were divided into three groups: strains showing all positive results in three tests, two positive in the first two tests, and all negative. Nevertheless, all phage-resistant strains showed that their pathogenic activities were reduced or completely lost.