• Korean Journal of Microbiology
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• v.44 no.1
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• pp.37-42
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• 2008

Optimal conditions for the biodegradation of endocrine-disrupting bisphenol A (BPA) were examined for the white rot fungus Trametes versicolor isolated in Korea. T. versicolor degraded 100% of 50 mg/L bisphenol A during 12 hr in yeast extract-malt extract-glucose (YMG) medium. When BPA was added to the 5-day preincubated fungal culture in YMG medium, all BPA was removed in 2 hr. T. versicolor could efficiently degrade BPA at $35^{\circ}C$, pH 6 in YMG medium. T. versicolor could more easily remove BPA of $1{\sim}25\;mg/L$ than that of higher concentrations ($50{\sim}100\;mg/L$) in YMG medium. T. versicolor degraded 100% of 50 mg/L BPA for 36 h in a minimal medium, which is lower degradation rate than that in YMG medium. Optimal conditions for BPA biodegradation in the minimal medium were similar to those in YMG medium. When BPA (50 mg/L) was added into domestic wastewater, it could be completely removed by T. versicolor. During the biodegradation of BPA by T. versicolor in YMG medium, its estrogenic activity decreased.

• The Korean Journal of Mycology
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• v.43 no.4
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• pp.239-246
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• 2015

Two fungal strains were isolated from rods of Quercus sp. (NAAS02335) and Pinus densiflora (NAAS05299) in Korea. These strains were identified as Gyrodontium sacchari by their morphological and mycological characteristics. The optimal growth temperature of NAAS02335 and NAAS05299 are $25^{\circ}C$ and $30^{\circ}C$, respectively. Production of cellulase, xylanase, and ligninase was tested on agar media supplemented dyes or substrates. Production of cellulase and xylanase of NAAS05299 was higher than those of NAAS02335, however ligninase activity of NAAS02335 was higher than that of NAAS05299. The activities of cellulase, xylanase, and amylase of strain NAAS05299 were estimated at 6.7~10.2 times higher than that of NAAS02335. Laccase activity was only estimated by strain NAAS02335. The lignocellulytic enzymes are induced by substrates such as rice straw, wooden chips of pine, oak, and poplar. The NAAS05299 was able to degrade filter paper completely after 4 weeks of culturing in liquid media containing a piece of filter paper at $28^{\circ}C$ with continuous shaking. NAAS05299 was able to degrade rice straw, pine chips, and oak chips after 4 months in solid culture, however NAAS02335 decomposed only rice straw among tested 4 kinds of biomass.

• Mycobiology
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• v.46 no.3
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• pp.224-235
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• 2018

Temperature is an important environmental factor that can greatly influence the cultivation of Auricularia cornea. In this study, lignin peroxidase, laccase, manganese peroxidase, and cellulose in A. cornea fruiting bodies were tested under five different temperatures ($20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$) in three different culture periods (10 days, 20 days and 30 days). In addition, the V4 region of bacterial 16S rRNA genes in the substrate of A. cornea cultivated for 30 days at different temperatures were sequenced using next-generation sequencing technology to explore the structure and diversity of bacterial communities in the substrate. Temperature and culture days had a significant effect on the activities of the four enzymes, and changes in activity were not synchronized with changes in temperature and culture days. Overall, we obtained 487,694 sequences from 15 samples and assigned them to 16 bacterial phyla. Bacterial community composition and structure in the substrate changed when the temperature was above $35^{\circ}C$. The relative abundances of some bacteria were significantly affected by temperature. A total of 35 genera at five temperatures in the substrate were correlated, and 41 functional pathways were predicted in the study. Bacterial genes associated with the membrane transport pathway had the highest average abundance (16.16%), and this increased at $35^{\circ}C$ and $40^{\circ}C$. Generally, different temperatures had impacts on the physiological activity of A. cornea and the bacterial community in the substrate; therefore, the data presented herein should facilitate cultivation of A. cornea.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.281-294
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• 2018

Molecular analysis using the internal transcribed spacer region sequences revealed that the strains used in this study, which were formerly identified as Panellus serotinus, are Panellus edullis. After Universal Fungal PCR Fingerprinting (UFPF) analysis, eight strains of P. edulis were divided into two groups. We conducted fundamental research on mycelial growth and sawdust cultivation to understand the cultural characteristics of eight wild P. edulis strains collected from Korean forests. All strains showed faster and denser mycelial growth on potato dextrose agar (PDA) than on other media (malt extract agar, Sabouraud dextrose agar). Optimal conditions for mycelial growth were: $20^{\circ}C$ on PDA, $25^{\circ}C$ on potato dextrose broth (PDB), and pH 5~8 on PDB at $25^{\circ}C$. Two strains (NIFoS 2407, 3993) were selected as excellent strains based on mycelial growth and density on PDA. NIFoS 2792 showed high cellulase activities on carboxymethyl cellulose (CMC) agar, and NIFoS 2387 and 2804 exhibited high laccase activities on ABTS-containing agar media. The mycelial growth of P. edulis was the fastest on Quercus acutissima and Q. mongolica sawdust media, and mycelial density was the highest on Quercus spp. sawdust-containing media. Sawdust cultivation of P. edulis was successful. The conditions were 80~85 days of cultivation period after spawn inoculation, 10~11 days for primordial formation at $17{\sim}18^{\circ}C$, and 15~20 days for fruiting growth. NIFoS 2804 and 3993 were selected as good strains in terms of cultivation period and mushroom production. These results could be useful for the artificial cultivation of P. edulis.