• The Korean Journal of Mycology
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• v.48 no.2
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• pp.125-133
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• 2020

A new oak mushroom cultivar 'Hwadam' was bred from monokaryotic strains of 'GMLE36062' and 'LE15401'. The optimum temperature for mycelial growth of 'Hwadam' on potato dextrose agar was 25℃. The cultivation period of 'Hwadam' lasted for 129 days until the first harvest of the fruiting bodies, including 35 days for spawn run, 84 days for browning, and 10 days for development of fruiting bodies. The fruiting bodies of 'Hwadam' had a hemispherical, brighter pileus and thicker stipe than the control cultivar (Sanjo 701ho). The three-cycle yield of 'Hwadam' was 554 g, which was higher than that of control cultivar (405 g). In addition, 'Hwadam' contained 79.4 mg/g of beta-glucan and 0.93 mg GAEs/g of phenolic compounds, which was similar to that of the control cultivar but higher than that of 'L808' and 'Chujae 2ho'.

• Food Science and Preservation
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• v.14 no.3
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• pp.315-322
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• 2007

The patulin producing capicity of Penicillium crustosum, an isolate from Korean apple, in various broth culture media, was investigated, and compared with patulin production by the standard strain P. griseofulvum(ATCC 46037). The maximal patulin production capacity of the P. griseofulvum ATCC 46037 was 2,029-2,829 ppm in 5-GYEP, SY and MEB broth media. The patulin-producing capacity of the isolated fungus(P. crustosum) attained 2,794 ppm in a 5-GYEP broth medium, but was only 324 and 11 ppm in SY and MEB media, respectively. There were no significant correlations between mycelial growth levels and patulin-producing ability in either P. crustosum or P. griseofulvum. The patulin production of P. griseofulvum was induced in the wide pH range of pH 3.0-11.0, while that of P. crustosum was induced in the acidic pH range pH 3.0-5.0. Patulin production levels were dependent on the carbon sources in the media and maximal patulin production by P. griseofulvum and P. crustosum was observed in media containing glycerol and fructose, respectively.

• The Korean Journal of Mycology
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• v.19 no.1
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• pp.54-60
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• 1991

In the traditional medicine, the basidiocarps of Poria cocos (Fr.) Wolf naturally collec­ted have been widely used as a traditional remedy for dropsy, diarrhea, gonorrhea and nervous disease more than 3500 years ago. It was recently found to be composed of the particular compounds having antitumor effects. Therefore, its demand has been gradually increased, whereas it is still dependent upon the natural harvest. The artificial cultivation of P. cocos was carried out to observe the morphological characteristics and to investigate the cultural characteristics of P. cocos isolates collected. The morphological characteristics of its basidiocarps was observed. The physiological aspects of its isolates were also investigated.

• The Korean Journal of Mycology
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• v.17 no.4
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• pp.223-228
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• 1989

This study was performed to obtain higher yield rate of protein-bound polysac-charide extracted from cultured broth and fruit body of Coriolus versieolor, basidiomycetes. 16002 strain produced 0.58%, the highest yield rate among four strains, and there was no significantly different yield in other three strains. The optimal liquid media were CVT-III to obtain higher yield of protein-bound polysaccharide comparing with the various culture media. Compared with several materials for substitution of medium source, the residue extract media of Coriolus versieolor fruit-body were yield rate similar to control, and addition of the extracts of ginseng residues increased 11.4-48%. And also compared with fruit bodies that were artificially cultured on the oak longs, 16002 strain produced the highest yield similar to the result of cultured broth. Fruit body of the prematures stage was more effective to obtain high yield rate.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.31-38
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• 1998

Since 1990, destructive yellow rots on Ganoderma lucidum caused by a soilborne fungus have been occurred in major cultivation areas of Korea. Incidences of the disease were 61% in Chulwon and 94% in Kanghwa area where the mushroom has been cultivated for 10 years, whereas the disease has not been found yet in new cultivation areas such as Moonkyung and Hongsung. when severely infected, inner tissues of bed-logs showed severe yellow and fruiting bodies of the mushroom was not produced. Infected tissues of bed-logs were readily distinguished from those of healthy ones by a distinctive brown border line. When the disease progressed, mycelia of Ganoderma lucidum were totally destroyed, and abundant ascocarps of the pathogen were formed inside the tissues of bed-logs showing yellowish green. The fungus derived from a single ascospore strongly lysed mycelia of Ganoderma lucidum growing on bottle media, and non-volatile components secreted by the pathogen were also highly inhibitory to mycelial growth of the mushroom fungus. The pathogen was identified as Arthrographis cuboidea based on its distinctive cultural and morphological characters. The fungus produced arthroconidia and unbrached conidiophores. The width of fungal conidia was distinctively wide as compared with the length. Colonies of the fungi were pale yellow to yellowish green on agar media. As a causal pathogen of yellow rot of Ganoderma lucidum., this fungus has not been reported yet in Korea.

• KSBB Journal
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• v.21 no.2
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• pp.96-102
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• 2006

Recently, it has been known that Hericium erinaceum is a one of the very useful functional materials with great attention in mushroom processing industry. In present study, a liquid culture which was not studied systematically until now, was conducted as a method of cultivation for H. erinaceum, and also examined the characteristics of the liquid culture and conditions of process optimization. A good basal medium was selected through the cultivation of 16 species mushroom media and the optimum condition for medium and cultivation were chosen by response surface method. From these results, the optimum condition of medium for mushroom was 3% glucose, 0.2% yeast extract/peptone(1:1) and 0.1% $KH_2PO_4/MgSO_4$(1:1) and also the optimal culture condition was obtained at inoculum of 13.42%, temperature of $22.3^{\circ}C$ and pH of 5.7. The mycelial dry weight of 9 g/I was obtained under these conditions and this amount was about 1.7 times higher than that which were cultivated in basal medium for 8 days.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.262-268
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• 2014

A fungal isolate DUCC5000 from a garden plant Pachysandra terminalis was identified as Paraconiothyrium brasiliense based on the results of morphological and molecular studies. The fungus formed brown to black conidiomata of (0.2-0.7)-2(-3.5) mm singly or as a group on PDA. Conidia measured $2-5{\times}1.8-3{\mu}m$ in size, hyaline, ellipsoid to short-cylindrical, and rounded at both ends. The internal transcribed spacer (ITS) DNA of the isolate shared 100% nucleotide sequence homology with those of known P. brasiliense isolates. Phylogenetic tree inferred from the ITS sequence analysis showed that the DUCC5000 isolate formed a clade with known isolates of P. brasiliense. The fungal mycelia grew better on oatmeal agar than on MEA and PDA. On PDA media under various pH conditions, fungal mycelial growth was observed at pH 9. Colony morphology of the fungus tended to alter depending on the kinds of nutrient media and pH condition. On chromagenic media, the fungus demonstrated its ability to produce extracellular enzymes including amyalse, avicelase, ${\beta}$-glucosidase, protease, and xylanase. However, in pathogenicity testing, no disease symptoms were observed on the leaves of P. terminalis. This strain is the first report on P. terminalis in Korea.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.152-159
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• 2010

The influence of urushiol, as an allergen on laccase property of Fomitella fraxinea was investigated. The enzyme production was reached to the highest level after 10 days, cultivation and the activity and mycelial biomass were increased by 2.5 and 1.5 folds, respectively, by adding urushiol in the culture medium. In liquid cultures using a Cu Mn-free medium, laccase lactivity was decreased by 3.8-9.2 folds, with similar dry cell weight. Two isoenzymes, were purified using anion exchange, hydrophobic interaction and size-exclusion chromatographies. Both isoenzymes are monomeric proteins, with $M_W$ around 67 kDa(Lac1) and 66 kDa(Lac2), and isoelectric points of 3.67 and 3.81. The optimal conditions for purified isoenzymes were found to be pH 4.5-5.0 and $30-35^{\circ}C$. Activity decreased by the addition of $Fe^{2+}$, $Mg^{2+}$, $Na^+$, and strongly inhibited by EDTA and sodium azide.

• Research in Plant Disease
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• v.18 no.2
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• pp.109-116
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• 2012

A bacterial strain antagonistic to some fungal phytopathogens was isolated from the stem of a Persimmon tree in Yeongam, Korea. This bacterium was identified as Bacillus subtilis by 16S rRNA gene sequencing and designated as B. subtilis GDYA-1. In in vivo experiment, the fermentation broth exhibited antifungal activities against Magnaporthe oryzae on rice plants, Phytophthora infestans on tomato plants, and Puccinia recondita on wheat plants. We isolated one antifungal compound and its chemical structure was determined by mass and $^1H$-NMR spectral data. The antifungal substance was identified as benzoic acid. It inhibited mycelial growth of M. oryzae, Rhizoctonia solani, Sclerotinia sclerotiorum, and P. capsici with minimum inhibition concentration (MIC) values, ranging from 62.5 to 125 ${\mu}g/ml$. Moreover, the substance effectively suppressed Phytophthora blight of red pepper caused by P. capsici in a pot experiment. To the author's knowledge, this is the first report on the antifungal activity of benzoic acid against phytopathogenic fungi. Benzoic acid and B. subtilis GDYA-1 may contribute to environmental-friendly protect crops from phytopathogenic fungi.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.313-320
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• 2010

Genetic instability of the rice blast fungus Magnaporthe oryzae has been suggested as a major factor underlying the rapid breakdown of host resistance in the field. However, little information is available on the mechanism of genetic instability. In this study, we assessed the stability of repetitive DNA elements and several key phenotypic traits important for pathogenesis after serially transferring two isolates though rice plants and an artificial medium. Using isolate 70-15, we obtained a total of 176 single-spore isolates from 10 successive rounds of culturing on artificial medium. Another 20 isolates were obtained from germ tubes formed at the basal and apical cells of 10 three-celled conidia. Additionally, 60 isolates were obtained from isolate KJ201 after serial transfers through rice plants and an artificial medium. No apparent differences in phenotypes, including mycelial growth, conidial morphologies, conidiation, conidial germination, appressorium formation, and virulence, or in DNA fingerprints using MGR586, MAGGY, Pot2, LINE, MG-SINE and PWL2 as probes were observed among isolates from the same parent isolate. Southern hybridization and sequence analysis of two avirulence genes, AVR-Pita1 and AVR-Pikm, showed that both genes were also maintained stably during 10 successive generations on medium and plants. However, one reversible loss of restriction fragments was found in the telomere-linked helicase gene (TLH1) family, suggesting some telomere regions may be more unstable than the rest of the genome. Taken together, our results suggest that phenotype and genotype of M. oryzae isolates do not noticeably change, at least up to 10 successive generations on a cultural medium and in host plants.