• Applied Biological Chemistry
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• v.40 no.4
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• pp.329-333
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• 1997

Phosphate solubilizing microorganisms (1,000 bacteria and 200 fungi) were isolated from soil around Kyungnam and Kyungbook regions using potato dextrose agar-calcium phosphate medium. A fungus with the greatest phosphate solubilizing activity was selected and identified to Penicillium sp. GL-101, based on the morphological characteristics of conidiophore and conidia; flask shape of phialide, simple branching type of conidiophore, and columnar shape of conidial head, in malt extract agar and potato dextrose agar media. The optimum temperature and initial pH to solubilize rock phosphate in potato dextrose broth-rock phosphate medium were $25^{\circ}C$ and pH 7.5, respectively. In these optimum conditions, phosphate solubilizing activities of Penicillium sp. GL-101 against four types of insoluble phosphate: tricalcium-phosphate, aluminium phosphate, hydroxyapatite and rock phosphate, were quantitatively determined. As results, this fungus highly discharged free phosphates to the culture broth with the concentrations of 1,152 ppm against tricalcium-phosphate, 565 ppm against rock phosphate, 292 ppm against aluminium phosphate, and 217 ppm against hydroxyapatite, respectively.

• Mycobiology
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• v.38 no.1
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• pp.17-25
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• 2010

The common split-gilled mushroom, Schizophyllum commune is found throughout the world on woody plants. This study was initiated to evaluate conditions for favorable vegetative growth and to determine molecular phylogenetic relationship in twelve different strains of S. commune. A suitable temperature for mycelial growth was obtained at $30^{\circ}C$. This mushroom grew well in acidic conditions and pH 5 was the most favorable. Hamada, glucose peptone, Hennerberg, potato dextrose agar and yeast malt extract were favorable media for growing mycelia, while Lilly and glucose tryptone were unfavorable. Dextrin was the best and lactose was the less effective carbon source. The most suitable nitrogen sources were calcium nitrate, glycine, and potassium nitrate, whereas ammonium phosphate and histidine were the least effective for the mycelial growth of S. commune. The genetic diversity of each strain was investigated in order to identify them. The internal transcribed spacer (ITS) regions of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 129 to 143 bp and 241 to 243 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical. A phylogenetic tree of the ITS region sequences indicated that the selected strains were classified into three clusters. The reciprocal homologies of the ITS region sequences ranged from 99 to 100%. The strains were also analyzed by random amplification of polymorphic DNA (RAPD) with 20 arbitrary primers. Twelve primers efficiently amplified the genomic DNA. The number of amplified bands varied depending on the primers used or the strains tested. The average number of polymorphic bands observed per primer was 4.5. The size of polymorphic fragments was obtained in the range of 0.2 to 2.3 kb. These results indicate that the RAPD technique is well suited for detecting the genetic diversity in the S. commune strains tested.

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.221-224
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• 1985

The life cycle of 17 species of Trichoderma was elucidated to seize the proper stage for observing the nuclear behavior and chromosome count. The most convenient stage for the purpose in their life cycle was the stage just before producing the asexual spore. Of the 17 species in the genus Trichoderma the haploid chromosome numbers were counted 5,6,7 and 10. Six chromosomes were most frequently observed. It is believed that the basic chromosome number is placed between 4 and 10, and that the number might be 6, referring to the related papers. It appears necessary to reclassify the single genus of Trichoderma into at least two or three genera.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.25-28
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• 2000

The effect of ionic osmotic potential (Ψ$\pi$), and matric potential (Ψm) in the range of -0.2 to -4.0 Mpa on mycelial growth of three species of Pleurotus (P.florida, P.ostrenatus and P.safor-caju) were determined over a range of temperature (15-3$0^{\circ}C$) on a 2% malt extract agar medium and compared with the Ψ$\pi$ effect on growth of two strains of Trichoderma green mould. With the ionic solute KCl, optimun Ψ$\pi$for growth was -0.2 MPa for P.floreda and in the range of -0.2 to -0.5 MPa, with slight growth at -3.0 MPa and with nogrowth at -4.0 MPa. Of the species of Pleurotus, P.florida grew signigicantly slower than the other two species. Growt of the species of Pleurocus was significantly slower when water potential (Ψ$\omega$) was modified matrically with polyethylene glycol (PEG) 8000 then osmotically with KCl. They were also more sensitive to changes in Ψm than Ψ$\pi$The optimum Ψm of the Pleurotus was -0.5 Ψm, with no growth below -3.0 MPa. Of the species of Pleurotus, P.florida was most sensitive and P.sajor-caju was more tolerent to lowered Ψ$\pi$,but P.sajor-caju was most sensitive to lowered Ψm. The growth rate of the Trichoderma green mould strains was much faster than that observed for the Pleurotus spp. Optimum growth for bot strains of Trichoderma was in the range of -0.2 to -0.5 MPa. Strain CNU 503 was more tolerant to water stress than strain CNU 501. Both strains were able to grow up to 30% of optimum growth at -4.0 MPa at 25-3$0^{\circ}C$.

• The Plant Pathology Journal
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• v.15 no.3
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• pp.152-157
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• 1999

An antibiotic compound was isolated from the culture of an antagonist against Fusarium oxysporum f. sp. sesami, Bacillus polymyxa strain KB-8, and tested for the control of Fusarium wilt of sesame in greenhouse conditions. Optimum conditions for culturing the antagonist to obtain the maximum antibiotic activity were determined using different culture media, initial medium acidity, and incubation periods for which yeast -malt extract agar with the initial acidity of pH 5 and over 13 days culture were best. Antibiotic substances extracted by methanol had 2 main fractions, KB-8A and KB-8B, in thin layer chromatography (OLC) with Rf values of 0.35 and 0.67 in a solvent system of chloroform : methanol = 7 : 3. The fraction KB-8A wa purified further by XAD-2, silica gel and Sephadex LH-20 column chromatography, and crystalization. Its minimum inhibitory concentrations (MICs) were $12.8\mu\textrm{g}$/ml for F. oxysporum and Alternaria mali, $6.4\mu\textrm{g}$/ml for Colletotrichum gloeosporioides and Rhizoctonia solani, and $3.2\mu\textrm{g}$/ml for Phytophthora capsici. Soil drenching of antibiotic KB-8A in the concentrations of $13.0\mu\textrm{g}$/ml and $26.0\mu\textrm{g}$/ml effectively inhibited the Fusarium wilt of sesame in a greenhouse test, which appeared to be comparable to the fungicide benlate of $6.5\mu\textrm{g}$ a. i./ml.

• The Korean Journal of Mycology
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• v.40 no.2
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• pp.93-97
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• 2012

Gamma ray irradiation mutagenesis was employed to get variants of Pleurotus eryngii with functionally enhanced and improved characteristics. Protoplasts released from P. eryngii were treated with gamma ray radiation under 0.25-1.25 KGy. Protoplast sample that showed fatality rate of 80% at the 0.25 KGy was spreaded on YPMGA (yeast, peptone, malt-extract, glucose, agar) and 500 mycelial colonies were randomly selected from the medium. Of them, 100 mutant strains with mycelial morphology and growth rate that differ to control strain were observed on PDA. The cellulase and laccase activity of 67 gamma ray-irradiated P. eryngii isolates with morphological variation were investigated. Among these, 5 isolates were higher cellulase. In addition, the genetic variation of the mutant strains was analyzed by PCR fingerprinting.

• Journal of the Korean Wood Science and Technology
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• v.33 no.2 s.130
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• pp.65-71
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• 2005

This study was performed to understand the interaction between Ophiostomataceae and basidiomycetes fungi during cultures, and whether the basidiomycetes fungi inhibit the growth and decolorize dark pigments of blue staining fungi. The conjoint cultivation was studied on 2% malt extract agar. The ability of basidial cultures to decolorize dark pigments of ophiostomatoid fungi was the main characteristics estimated during this study. More than half of basidial cultures were characterized by deadlock interaction with blue staining fungi. In the dual cultures, where basidial partners were presented by Agaricus bisporus(64), Laetiporus sulphureus(L01/89), Trametes versicolor(09) and unknown fungus(02), antagonism was found at the phase of primary contact of colonies. Replacement interaction resulted usually in decreasing dark colour of substrate was observed for 11 basidial cultures that were belonging mainly to white-rot fungi. Among them Abortiporus biennis(123), Antrodiella hoehnelii(S28/91), Bjerkandera fumosa (137), and Gleophyllum odoratum(124) were characterized by the absence of deadlock-phase: they began to grow over dark colonies of their partners just after primary contact. Basidiomycetes did not affect strongly the pigments of Ceratocystis spp. and Leptographium sibirica isolates, but completely decolorized colonies of Ophiostoma ips and to a smaller degree Ophiostoma minus. Antrodiella hoehnelii(S28/91), Bjerkandera fumosa(137), Gleophyllum odoratum(124) and Trametes versicolor(B18/91) cultures were found to be the most active in decreasing dark color of blue staining fungi colonies. The cultures were recommended for further development as agents of biopulping of wood chips and bio-control of blue stain in woods.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.53-62
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• 1998

In this research, 7 species of white rot fungi were used for determining the resistance against pentachlorophenol (PCP). Three fungi with good PCP resistance were selected for evaluating the biodegradability, and biodegradation mechanism by HPLC and GC/MS spectrometry. Among 7 fungi, there were significant differences on PCP resistance on 4 different PCP concentrations. In the concentrations of 50 and 100ppm ($\mu$g of PCP per g of 2% malt extract agar), most fungi were easily able to grow, and well suited to newly PCP-added condition, but in that of more than 250ppm, the mycelia growths of Ganoderma lucidum 20435, G. lucidum 20432, Pleurotus ostreatus, and Daldinia concentrica were significantly inhibited or even stopped by the addition of PCP to the culture. However, Trametes versicolor, Phanerochaete chrysosporium, and Inonotus cuticularis still kept growing at 250ppm, indicating the potential utilization of wood rot fungi to high concentrated PCP biodegradation. Particularly, P. chrysosporium even showed very rapid growth rate at more than 500ppm of PCP concentration. Three selected fungi based on the above results showed an excellent biodegradability against PCP. P. chrysosporium degraded PCP up to 84% on the first day of incubation, and during 7 days, most of added PCP were degraded. T. versicolor also showed more than 90% of biodegradability at 7th day, and even though the initial stage of degradation was very slow, I. cuticularis has been approached to 90% at 21 st day after incubation with dense growing pattern of mycelia. Therefore, the PCP biodegradability was definitely dependent on the rapid suitability of fungi to newly PCP-added condition. In addition, the PCP biodegradation by filtrates of P. chrysosporium, T. versicolor, and I. cuticularis was very minimal or limited, suggesting that the extracellular enzyme system may be not so significantly related to the PCP biodegradation. Among the biodegradation metabolites of PCP, the most abundant one was pentachloroanisole which resulted in a little weaker toxicity than PCP, and others were tetrachlorophenol, tetrachloro-hydroquinone, benzoic acid, and salicylic acid, suggesting that PCP may be biodegraded by several sequential reactions such as methylation, radical-induced oxidation, dechlorination, and hydroxylation.

• Korean Journal of Heritage: History & Science
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• v.14
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• pp.225-250
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• 1981

The investigation of air fungal population in the storages to keep papers and textiles that are designated as important folk life materials or treasures was carried out from Dec. 17 to. 23, 1980. Isolation media was used for malt extract agar with chloramphnicol to prevent bacterial contamination. Isolation and identification of air fungi from the four preserved rooms were Cladosporium cladosporioides, Alternaria chlamydospora, Aspergillus fumigatus, A. versicolor, Eurotium chevalieri, Penicillium charlesii var. rapidum, P. oxalicum. P. viridicatum, Trichoderma viride, Acremomium sp., Mucor sp. and Yeast. It was found that nine species in eight genera was isolated. Among them, underscribed species in Korea was two species ; Eurotium chevalieri and Penicillium visidicatum. The fungal population of four storages was showed to be dominant species such as Cladosporium cladosporioides and the order was Acremonium, Penicillium, Aspergillus, Trichoderma, Alternaria and Eurotium. Eurotium chevalieri was ascomycetous fungi including distinctive ascospores in cleistothecia, the filamentous fungi was directly isolated from the papers and cellulose materials showing to be fourteen species in eight genera. The most species of the fungi isolated was also Cladosporium cladosporioides and the other fungi were found as Acremonium, Penicillium, Aspergillus and Trichoderma. It was confirmed that underscribed fungi were two species ; Mucor racemosus and Penicillium spinulosvm. The effect of four antifungal agents, benzoic acid, sorbic acid, dehydroacetic acid and thymol was also examined on eight species of Aspergillus, Penicillium, Cladosporium. and Tricoderma. this results were shown that more than 0.5% concentration of thymol inhibited the grow of all fungalspecies and other three chemicals appeared various inhibition zones of fungal growth depending in their different concentrations.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.68-74
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• 2000

Penicillium oxalicum (PENOX) has shown the potential as a biocontrol agent(5CA) for control of a weed, clover(Trifolium repens L.) in grass plots. The bioherbicidal activity may be due to germinative and growth capacities and substrate availability of the agent over a range of environmental factors. The influences of different water activities($0.94{\sim}0.995\;a_w$) and temperatures($18{\sim}30^{\circ}C$) on mycelial growth, conidial germination, sporulation oil 2% MEA(malt extract agar) adjusted to different water activities with glycerol, and carbon source utilization using BIOLOG GN MicroPlate were determined in vitro. Decreases in $a_w$ on MEA caused a reduction in mycelial growth and conidial germination depending on temperature. The mycelial growth of PENOX was greatest at $30^{\circ}C/0.995\;a_w$. At some lowered water activity($0.97\;a_w$), the growth was similar between 25 and $30^{\circ}C$, and considerably decreased at lowered temperature($20^{\circ}C$). The germination rate was also greatest at $30^{\circ}C/0.995\;a_w$. Lag phase times for PENOX at $18^{\circ}C$ on MEA were >6hrs at tile whole $a_w$ level tested, and at 18 and $25^{\circ}C$ they were >18hrs and >12hrs at $0.94\;a_w$, respectively. However, its sporulation was some better at $0.97\;a_w$ than $0.995\;a_w$ or $0.94\;a_w$, and better at $20^{\circ}C$ than $30^{\circ}C$. In contrast, the number of carbon sources(niche size) utilized by PENOX varied with $a_w$ and temperature. Under some water stress condition($0.95\;a_w$), the agent utilized smaller number of carbon sources than $0.995\;a_w$ depending on temperature. The niche size at 0.995 and $0.95\;a_w$ were highest at $25^{\circ}C$, and showed 86 and 65, respectively. At $30^{\circ}C$, the niche size at 0.995 and $0.95\;a_w$ showed 84 and 50, respectively. There was no carbon source utilized by PENOX at $0.90\;a_w$ regardless of temperature. These information of tile fungal ecophysiology will be useful for the effective development of BCA.