• Microbiology and Biotechnology Letters
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• 제31권2호
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• pp.124-128
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• 2003

In order to isolate and characterize a novel fungal strain capable of producing cellulase, each samples of the old rice straw, soil, and the old tree were screened by congo red test. One of the fungi screened has been identified as Aspergillus tubingensis strain from the results of the phylogenic analysis based on partial DNA sequence and the basis of its biochemical properties. A carboxymethyl cellulase activity of the strain was higher than that of A. oryzae KCTC 6291. In CMCase activity measurement, it wasn't sensitive about pH 2.0, 3.0, 4.0, but the enzyme was more stable than A. oryzae under the various pH and temperature conditions and the enzyme activity was more similar to neutrality and alkali. Therefore, it could be suggested that the isolated strain has a potential possibility for the developing of the probiotics.

• Mycobiology
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• 제32권2호
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• pp.88-94
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• 2004

Protoplasts of the wild type strain of Pleurotus osteatus were mutagenized with UV light, and 3,000 colonies were examined for abnormal mycelial and fruiting phenotypes. Forty one strains displayed variant phenotypes in mycelia and fruiting processes. The variant phenotypes were classified into 6 groups: (1) auxotrophic strains, which are incapable of growing on minimal media and can only grow when provided with their specific requirements; (2) abnormal vegetative strains, which grow very slowly on minimal and complete media; (3) primordiumless strains, which fail to develop to the formation of primordia; (4) maturationless strains, which form primordia, but do not form mature fruiting bodies; (5) specifically colored strains, which have Specific bluish grey or bluish white pileus; (6) poorly spored strains, which fail to produce basidiospore or which produce few spores. These variant strains may be useful in genetic breeding programs and for the studies of fungal development and genetics.

• Mycobiology
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• 제43권1호
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• pp.49-56
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• 2015

The present study is the first report on the isolation of Penicillium menonorum from rhizosphere soil in Korea and its identification based on morphological characteristics and internal transcribed spacer gene sequence. The fungal isolate was named KNU-3 and was found to exhibit plant growth-promoting (PGP) activity through indole acetic acid (IAA) and siderophore production, as well as P solubilization. KNU-3 produced 9.7 mg/L IAA and solubilized 408 mg of $Ca_3PO_4/L$, and inoculation with the isolate significantly (p < 0.05) increased the dry biomass of cucumber roots (57%) and shoots (52%). Chlorophyll, starch, protein, and P contents were increased by 16%, 45%, 22%, and 14%, respectively, compared to plants grown in uninoculated soil. The fungus also increased soil dehydrogenase (30%) and acid phosphatase (19%) activities. These results demonstrate that the isolate KNU-3 has potential PGP attributes, and therefore it can be considered as a new fungus to enhance soil fertility and promote plant growth. Moreover, the discovery of PGP ability and traits of this fungus will open new aspects of research and investigations. In this study, plant growth promotion by P. menonorum KNU-3 is reported for the first time in Korea after its original description.

• Korean Journal of Plant Resources
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• 제20권2호
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• pp.216-219
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• 2007

Root colonization by a rhizobacterium, Pseudomonas chlororaphis O6, elicited induced systemic resistance (ISR) in the leaves of cucumber plants against fungal and bacterial pathogens. To understand the role of unique genes during strain O6-mediated ISR, a suppressive subtractive hybridization method was undertaken and led to isolation of twenty-five distinct genes. The transcriptional levels of all the genes showed an increase much earlier under O6 treatment than in water control plants only after challenge with pathogen, while no difference detected on the plants without pathogen challenge. This suggests that O6-mediated ISR is associated with the priming phenomenon, an enhanced capacity for the rapid and effective activation of cellular defense responses after challenge inoculation.

• The Plant Pathology Journal
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• 제35권6호
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• pp.674-683
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• 2019

Some species of the Trichoderma genus are reported as the major problem in oak wood mushroom production in Korea. In spite of economic loss by the fungi, scientific information on airborne Trichoderma species is not much available. To generate information for disease management development we analyzed airborne Trichoderma. A total of 1,063 fungal isolates were purely obtained from indoor air sampling of cultivation houses used for oak wood mushroom using sawdust media. Among the obtained isolates, 248 isolates were identified as Trichoderma fungi including T. harzianum, T. atroviride, T. citrinoviride, and T. pseudokoningii, by morphological and molecular analysis. T. harzianum was dominant among the four identified species. All the four Trichoderma species grew fast on solid nutrient media tested (potato dextrose agar [PDA], malt extract agar [MEA], Czapek's Dox + yeast extract agar [CYA] and cornmeal dextrose agar). Compact mycelia growth and mass spore production were better on PDA and CYA. In addition, T. harzianum and T. citrinoviride formed greenish and yellowish mycelium and spores on PDA and CYA. Greenish and yellowish pigment was saturated into PDA only by T. pseudokoningii. These four Trichoderma species could produce extracellular enzymes of sawdust substrate degradation such as β-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease. Their mycelia inhibited the growth of oak wood mushroom mycelia of two tested cultivars on dual culture assay. Among of eleven antifungal agents tested, benomyl was the best to inhibit the growth of the four Trichoderma species. Our results demonstrate that the airborne Trichoderma fungi need to be properly managed in the cultivation houses for safe mushroom production.

• Korean Journal of Organic Agriculture
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• 제23권4호
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• pp.951-962
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• 2015

To develop environment-friendly agricultural products with anti-microbial activity against Sclerotinia sclerotiorum as a pathogen of sclerotium disease, Aristolochia tagala Champ. was extracted by methanol and its extract was fractionated into several solvent fractions. The chloroform fraction, which showed the highest antimicrobial activity, was separated by column chromatography and obtained forty three subfractions. The forty three fractions were searched the anti-fungal activities by bioassay. The most active No. 26 subfraction was analyzed by GC-MS. Each mass spectra, corresponding to each peak of chromatogram, was compared to MS database of Wiley library. As a result, 2,4-di-tetra-butyl-phenol, 2-mono-palmitin, 1-mono-stearin were profiled as maine compounds in No. 26 subfraction. Bioassay using commercial 1-mono-stearin to test for the anti-microbial activity conformed the antimicrobial active compound. In conclusion, 1-mono-stearin identified from Aristolochia tagala Champ. was antimicrobial chemical against Sclerotinia sclerotiorum.

• Journal of Veterinary Clinics
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• 제28권2호
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• pp.254-257
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• 2011

A 2-year-old bearded dragon was referred to the Veterinary Medical Center at the College of Veterinary Medicine, Chungbuk National University with reduced activity and anorexia. On fecal examination, over growth of a bacteria and the proliferation of a yeast-like organism were found. The patient diagnosed with enteritis. By using fungal cultures and molecular typing, the yeast was identified as Pichia (P.) burtonii. The bearded dragon was treated with oral ketoconazole and trimethoprim/sulfamethoxazole. After 3 days, the dragon was recovered and fecal examination showed that the yeast had disappeared from the feces. The strain P. burtonii is supposed opportunistic pathogen in bearded dragon with enteritis according to its reports in a human. This report is the first paper about overgrowth of P. burtonii in a bearded dragon.

• Mycobiology
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• 제36권1호
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• pp.13-18
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• 2008

Eight distinct bacteria were isolated form diseased mycelia of the edible mushroom, Pleurotus eryngii. 16S rDNA sequence analysis showed that the isolates belonged to a variety of bacterial genera including Bacillus (LBS5), Enterobacter (LBS1), Sphingomonas (LBS8 and LBS10), Staphylococcus (LBS3, LBS4 and LBS9) and Moraxella (LBS6). Among them, 4 bacterial isolates including LBS1, LBS4, LBS5, and LBS9 evidenced growth inhibitory activity on the mushroom mycelia. The inhibitory activity on the growth of the mushroom fruiting bodies was evaluated by the treatment of the bacterial culture broth or the heat-treated cell-free supernatant of the broth. The treatment of the culture broths or the cell-free supernatants of LBS4 or LBS9 completely inhibited the formation of the fruiting body, thereby suggesting that the inhibitory agent is a heat-stable compound. In the case of LBS5, only the bacterial cell-containing culture broth was capable of inhibiting the formation of the fruiting body, whereas the cell-free supernatant did not, which suggests that an inhibitory agent generated by LBS5 is a protein or a heat-labile chemical compound, potentially a fungal cell wall-degrading enzyme. The culture broth of LBS1 was not inhibitory. However, its cell-free supernatant was capable of inhibiting the formation of fruiting bodies. This indicates that LBS1 may produce an inhibitory heat-stable chemical compound which is readily degraded by its own secreted enzyme.

• Journal of Conservation Science
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• 제7권1호
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• pp.31-41
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• 1998

Two isolation methods using the open plate and air sampler were applied to examine microbial distribution as an environmental factor for conservation of cultural properties in the War Memorial in Korea. The numbers of fungi were the abundant in the air of entrance and inside of the exhibition room where visitors were crowded, compared with inside of repository rooms. Fungal and bacterial distributions in the exhibition room during exhibition period were higher than during nonexhibition period, These results are due to the inflow of air current carrying microoganisms to the exibition rooms from outside with visitors. Fungi isolated from the War Memorial were identified as 19 species and one thermophilic fungus, Neurospora crassa. The majority of the isolated fungi are seemed to cause damage to cellulose materials in the Memorial.

• Applied Biological Chemistry
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• 제28권2호
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• pp.98-105
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• 1985

In the sheep and cattle's rumen, facultative anaerobic cellulolytic bacteria were isolated by using Hungate's roll tube technique. In the 21 isolated species, one was screened by its strong cellulolytic activity and identified as Cellulomonas fimi C-14 by investigate morphological, cultural, physiological characteristics and electron microgram. Optimum conditions of the cell growth and enzyme production were pH 6.5 an $30^{\circ}C$, Thiamine and biotin support a good growth of C. fimi C-14. In the enzyme activities, Crystalline cellulose hydrolyzing activity, CMCase activity and ${\beta}-glucosidase$ activity were 20.6, 226.6 and 0.56$(unit{\times}10^3/ml)$ at pH 6.0, $40^{\circ}C$. By addition of fungal cellulase, enzyme activity was increased. Simultaneous Saccharification Fermentation is better than two step fermentation in ethanol yield with Saccharomyces cerevisiae DY2.