• Journal of the Korean Wood Science and Technology
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• 제36권5호
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• pp.1-10
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• 2008

Decay and mold resistance of zinc borate (ZB) and calcium borate (CB) modified oriented strandboard (OSB) from southern mixed hardwood and southern yellow pine was investigated in this study. Brown rot fungus Gloeophyllum trabeum and white-rot fungus Trametes versicolar were used to examine the decay resistance of the OSB. The OSB test specimens were colonized by brown and white rot fungal mycelium in both the brown and white-rot culture bottles after 8 and 12 weeks, respectively. The wood species and fungus type had the significant effects on the decay resistance. Brown rot decay was evident for all untreated southern pine and mixed hardwood controls. The white-rot decay, however, did not show significant weight loss at both species control samples. The incorporation of ZB and CB composites provides suitable protection against brown-and white-rot fungi. No significant weight loss was observed from the borate treated OSB.

• Journal of the Korean Wood Science and Technology
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• 제42권2호
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• pp.214-221
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• 2014

The deterioration in wood by the brown-rot fungus (Fomitopsispalustris) and the white-rot fungus (Trametesversicolor) were measured using ultrasonic velocity. Those were used for the decay exposure and 4 wood species of wood as the test specimens, Pinusdensiflora, Larixkaempferi, Pinuskoraiensis and Pinusrigida, were chosen with both the brown- and white-rot culture petridish during 12 weeks. After 12 weeks, the decrease rate of ultrasonic velocity was measured at 10~15%. In both brown- and white-rot exposure experiments, P. rigida showed significant decrease in ultrasonic velocity (20%), L. kaempferi on the other hand did not show decrease in ultrasonic velocity. After the fungal exposure experiment, the inside of specimens was investigated by computer tomography (C/T). After C/T investigation, bending tests were performed.

• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.737-752
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• 2000

Wood-rotting basidiomycetous fungi are the most efficient degraders of lignin on earth. The white-rot fungus Phanerochaete chrysosporium has been used as a model microorganism in the study of enzymology and its application. Because of the ability of the white-rot fungus to degrade lignin, which has an irregular structure and large molecular mass, this fungus has also been studied in relation to degrading and mineralizing many environmental pollutants. The fungus includes an array of enzymes, such as lignin peroxidase (LiP), manganese-dependent peroxidase (MnP), cellobiose:quinone oxidoreductase, and $H_2O_2$-producing enzymes and also produces many other components of the ligninolytic system, such as veratryl alcohol (VA) and oxalate. In addition, the fungus has mechanisms for the reduction of degradation intermediates. The ligninolytic systems have been proved to provide reductive reactions as well as oxidative reactions, both of which are essential for the degradation of lignin and organopollutants. Further study on the white-rot fungus may provide many tools to both utilize lignin, the most abundant aromatic polymer, and bioremediate many recalcitrant organopollutants.

• 한국환경과학회지
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• 제7권3호
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• pp.263-268
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• 1998

Decolorization of congo red, rhodamlne B was investigated by the white rot fungus Irpex lacteus welch has biodegrading capability of various recalcitrants. White rot fungus Irpex lacteus is Immobilized by PVA-freezing method. An Immobilized Irpex lacteus decolorizes 91% of congo red In 8 days under culture with glucose 2%(Initial cone.). It also showed 70% of decolorization at 3 days In the state of putting MnSO4 1mM. But, rhodauune B has no significant differences about decolorization among different mixture ratio of Irprx lacteus with PVA, concentration of carbon, nitrogen and manganese sulfate.

• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.809-812
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• 2019

Bacterial strains that improve mycelial morphology and growth of white-rot fungi in liquid medium could enhance the impact of white-rot fungi towards lesser recovery of neonicotinoids when cocultured. This was demonstrated by the recovery of clothianidin and acetamiprid from cocultures of the white-rot fungus Phlebia brevispora strains with two mycelial-growth-promoting bacteria, Enterobacter sp. TN3W-14 and Pseudomonas sp. TN3W-8. Clothianidin recovery from cocultures of white-rot fungi and bacteria was over 40% lower than that from axenic microbial cultures and mixed-bacterial cultures. About 20% less acetamiprid was equally recovered from both TMIC33929+TN3W-14 cocultures and mixed-bacterial cultures than from axenic fungal and bacterial cultures.

• Mycobiology
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• 제47권1호
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• pp.87-96
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• 2019

Fungi produce various secondary metabolites that have beneficial and harmful effects on other organisms. Those bioactive metabolites have been explored as potential medicinal and antimicrobial resources. However, the activities of the culture filtrate (CF) and metabolites of whiterot fungus (Schizophyllum commune) have been underexplored. In this study, we assayed the antimicrobial activities of CF obtained from white-rot fungus against various plant pathogens and evaluated its efficacy for controlling anthracnose and gray mold in pepper plants. The CF inhibited the mycelial growth of various fungal plant pathogens, but not of bacterial pathogens. Diluted concentrations of CF significantly suppressed the severity of anthracnose and gray mold in pepper fruits. Furthermore, the incidence of anthracnose in field conditions was reduced by treatment with a 12.5% dilution of CF. The active compound responsible for the antifungal and disease control activity was identified and verified as schizostatin. Our results indicate that the CF of white-rot fungus can be used as an eco-friendly natural product against fungal plant pathogens. Moreover, the compound, schizostatin could be used as a biochemical resource or precursor for development as a pesticide. To the best of our knowledge, this is the first report on the control of plant diseases using CF and active compound from white-rot fungus. We discussed the controversial antagonistic activity of schizostatin and believe that the CF of white-rot fungus or its active compound, schizostatin, could be used as a biochemical pesticide against fungal diseases such as anthracnose and gray mold in many vegetables.

• The Plant Pathology Journal
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• 제20권1호
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• pp.58-62
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• 2004

White root rot of wild white clover (Trifoliorum repens) caused by isolate BWC98-105 has been first reported in Korea. Typical symptoms on root include water-soaked and dark-brown rot, resulting in complete blight of the whole plant. The fungus grew well at $20-28^{\circ}C$ and produced abundant sclerotia at 10-15 days after full mycelial growth on potato dextrose agar. Sclerotia were brown to dark-brown in color and 1-3 mm in length. When white clover plants were inoculated with mycelial suspension ($10^5$ cfu/ml) of isolate BWC98-105, the plant shoots were killed within 4-6 days and the roots were completely blighted. Sclerotia were also formed on the surface of the root covered with whitish mycelia within 10-15 days in the field. All nine isolates developed high incidences of white root rot disease on white clover seedlings, of which the symptoms were similar to those observed in the fields. Hence, their pathogenicity was confirmed on white clover. The infection rate of the fungal isolates varied from 78.5% to 95.2%, among which BWC98-105 was the most virulent isolate. The weeding efficacy of the fungus was maintained until the following year, leading to a significant reduction of reshooting. The fungus was specifically parasitic to white clover, but not to four lawn species including zoysiagrass (Zoysia japonica) under greenhouse test. The fungus also had no response to some Gramineae species including rice, but caused little damage to five species of Leguminosae.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1421-1430
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• 2009

With an aim to evaluate dye decolorization by white rot fungus on natural living conditions, reproducing by solid-state fermentation, the process of triphenylmethane dyes decolorization using the white rot fungus P. ostreatus BP, cultivated on rice straw solid-state medium, has been demonstrated. Three typical dyes, including malachite green, bromophenol blue, and crystal violet, were almost completely decolorized by the fungus after 9 days of incubation. During the process of dye decolorization, the activities of enzyme secreted by the fungus, and the contents of soluble components, such as phenolic compounds, protein, and sugar, changed regularly. The fungus could produce ligninolytic, cellulolytic, and hemicellulolytic enzymes and laccase was the most dominant enzyme in solid-state medium. Laccase, laccase isoenzyme, and the laccase mediator could explain the decolorization of malachite green, bromophenol blue, and crystal violet by the fungus in solid-state medium, respectively. It is worth noting that the presence of the water-soluble phenolic compounds could stimulate the growth of fungus, enhance the production of laccase, and accelerate dye decolorization.

• Mycobiology
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• 제30권4호
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• pp.244-246
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• 2002

A destructive stem rot of tomato(Lycopersicon esculentum) occurred sporadically some farmers' fields in Jinju City, Gyeongnam province in Korea. The infected plants also showed stem, crown rot or whole plant blight. White mycelium spread over stems of infected plants and formed sclerotia on the old lesions nearby soil surface. The fungus showed maximum mycelial growth around $30^{\circ}C$. The fungus formed white colony on PDA, usually with many narrow mycelial strands in the aerial mycelium and the width were $4.0{\sim}9.8{\mu}m$. The typical clamp connections were formed on the mycelium. Numerous sclerotia was formed on PDA at $30^{\circ}C$. The shape of sclerotia was globoid and $1.0{\sim}3.0$ mm in size. The fungus was isolated repeatedly from the infected tissues and the pathogenicity was confirmed to tomato and identified as Sclerotium rolfsii. This is the first report on the stem rot of tomato caused by S. rolfsii in Korea.

• The Plant Pathology Journal
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• 제20권2호
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• pp.103-105
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• 2004

A destructive stem rot of strawberry (Fragaria x ananassa cv. Akihime) sporadically occurred in farmers' fields in Daegok-myon, Jinju city, Gyeongnam province in Korea. The infected plants showed stem and crown rot, with occasional blighting of the whole plant. White mycelia appeared on stems of infected clones and sclerotia formed on the old lesions near soil surface. The fungus formed white colony on PDA and showed maximum mycelial growth and sclerotial formation at $30^{\circ}C$. The fungus usually have many narrow hyphal strands, 2.6-10.0 $\mu\textrm{m}$ in width, in the aerial mycelium. Typical clamp connections were formed on the mycelium. Sclerotia were spherical and 1.0-2.4 mm in size. The fungus was repeatedly isolated from infected tissues and identified as Sclerotium rolfsii. Its patho-genicity was confirmed when inoculated onto straw-berry. This is the first report on the stem rot of strawberry caused by S. rolfsii in Korea.