• The Korean Journal of Mycology
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• v.33 no.1
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• pp.30-34
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• 2005

Fifteen PGPF (plant growth promoting fungi) isolates were selected from 728 fungal isolates collected from rhizosphere of zoysiagrass in Korea. Identification of the 15 isolates was based on their morphological characteristics. They were classified as Gliocladium sp. (n=1), Penicillium sp. (n=5), Trichoderma sp. (n=3), Fusarium sp. (n=3), and unidentifed species (n=3). Of the 15 isolates, six (PF-31, PF-136, PF-238, PF-255, PF-395, PF-420) significantly promoted the growth of tomato seedlings, and three (PF-31, PF-101, PF-255) also promoted the growth of hot pepper and two (PF-31, PF-225) also promoted the growth of cucumber, The 15 PGPF isolates were divided into 4 groups based on root colonizing ability. Isolates PF-17, PF-101 and PF-225 were included in the group 1, which had high root colonizing ability.

• Food Science and Preservation
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• v.10 no.2
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• pp.224-229
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• 2003

This study was carried out to isolate of antagonistic bacterium to Allium cepa L. pathogens. A total of 250 strains were isolated from A. cepa L. roots. The isolates were screened for antagonism to A. cepa L. pathogens and the isolated strain No. YJ-4 was selected among these bacteria. It was identified as Bacillus ehimensis based on morphological and physiological characteristics according to the Bergey's mannual of systematic bacteriology, Sherlock system of Microbial ID Int and 165 rDNA sequences methods. Bacillus ehimensis YJ-4 showed broad spectrum of antibacterial and antifungal activities against plant pathogens as Alternaria porri, Botrytis cinerea, Erwinia carotovora subsp. carotovora Fusarium of oxysporium, penicillium sp., Pseudomonas sp., Rhizoctonia solani, Sclerotium cepivotum, Septoria sp., Stemphylium botryosum. Speially B. ehimensis YJ-4 showed high antifungal activity on growth against F. oxysporium, the causal agent of onion Fusarium wilt.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.70-76
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• 1990

Twenty-one strains isolated, cellulose decomposing fungi, were identified on the basis of morphological, physiological and biochemical properties as Acremonium sp., Aspergillus sp., Chaetomium sp., Chrysonilla sp., Doratomyces sp., Fusarium sp., Gliomastix sp., Penicillium sp., Trichoderma sp., Varicosporium sp. and Verticillium sp.. The optimum tempeture for growth was in the range of $20-30^{\circ}C$. Most of the isolated stains utilized all tested carbon sources, and scarcely utilized urea as a nitrogen source. Only the strain No.2 had high activity of cellulase.

• Research in Plant Disease
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• v.17 no.3
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• pp.280-287
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• 2011

This investigation was undertaken to survey toxigenic fungal contamination of various rice samples in 93 rice processing complexes (RPC) in Korea. Rice was grown in 2009 and the samples were collected in 2010. Seven types of rice samples such as unhusked, brown, blue-tinged, discolored, polished, half-crushed, and rice husks were obtained from each RPC. One-hundred and five grains of each sample were placed on PDA plates after surface disinfection. The incidence of fungal contaminants was 26.8%. Aspergillus spp. was the most dominant fungal contaminants and Fusarium spp. was the most frequently occurred in samples. The heaviest Fusarium contamination was found in unhusked grain, rice husks, and bare blue-tinged rice and followed by colored rice whereas broken rice was the least contaminated. Regional difference of fungal contamination was distinctive. Fusarium incidence in the rice samples from southern region of Korea including Jeolla and Gyeongsang Provinces was higher than those from central region including Chungcheong, Gyeonggi, and Gangwon Provinces. In contrast to Fusarium spp., Aspergillus spp. and Penicillium spp. were dominated in brown and polished rice samples and their incidences were more severe in central region than southern region. The major contaminants shown more than 1% of kernels infected were Aspergillus (5.0%), Fusarium (2.0%), Alternaria (1.4%), Dreschlera (1.3%), Penicillium spp. (1.3%), and Nigrospora spp. (1.0%). Collectotrichum, Pyricularia, Myrothecium, Epicoccum, Cladosporium, Moniliella, Gloeocercospora, Chaeto- mium, Curvularia, Phialopora, Acremonium, Gliomastix, Trichoderma, Rhizopus, Phomopsis, Paecilomyces, Genicularia, Geotrichum, Acremoniella, Rhizoctonia, Phoma, Oidiodendran, and Candida spp. were among the rest observed at low incidence. The major contaminants of rice samples were well-known as toxigenic fungal genera so toxin producibility of these fungal isolates is necessary to be examined in future. It is also needed to study Myrothecium spp. on species level as it was detected for the first time in rice.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.112-118
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• 1988

The effect of gamma irradiation of microbiological and physicochemical properties of raw ingredients (thirteen kinds of protein sources) for the mixed feed were investigated. The total aerobic bacteria counts in the samples was ranged from $10^2$ to $10^7$cells/g. After 5 to 7 kGy irradiation, the total count was reduced by 3 to 4 log cycles. Coliforms were detected in seven samples and the range was from $10^4$ to $10^6$cells/g. Enteric pathogens were found only in fish meal and poultry byproduct as $10^2$ to $10^6$cells/g. They were sensitive to radiation and completely sterilized by 3 to 5 kGy irradiation. Total fungi count was ranged from $10^1$ to $10^4$cells/g in all samples. They were osmophiles such as Aspergillus, Penicillium, Cladosporium, Aureobasidium and Rhizopus and were destroyed by 3 to 7 kGy irradiation. Five species of potential mycotoxin producers including Aspergillus flavus were also identified. Physicochemical properties, such as total amino acid content, TBA value, POV and color difference showed that irradiation with optimum does was less detrimental than autoclaving.

• Journal of Life Science
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• v.8 no.5
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• pp.537-549
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• 1998

This investigation was performed to isloate and identify the total bacteria, Staphylococcus spp. and fungi from the indoor air exposed for 30 minutes on the blood agar plate at the 27 places in a hospital. Antibiotic susceptibility tests of the isolated bacteria were also studied. The mean numbers of total bacteria, Staphylococci spp. and fungi were 26, 17, and 2 in the summer and 19, 8, and 2 in the winter, respectively. Staphylococcus epidermidis was the most common isolated bacteria, and the next was Staphylococcus aureus, Aerococcus spp., Micrococcus spp., and Bacillus spp. from the indoor-air of hospital. Aspergillus spp., Cephalosporum spp., Curvularia spp., penicillium spp., and Phialophora spp. was frequently isolated from the indoor-air of hospital. The 109 strains of isolated Staphylococcus epidermidis sho-wed resistance to tetracycline(45.0%), methicillin(40.2%), erythromycin(31.2%), and kanamycin(24.8%). The 76 strains of isolated Staphylococcus aureus showed resistance to erythromycin(71.7%), methicillin(63.2%), kanamycin (44.7%), tetracycline(39.5%), and ampicillin(32.9). The 67 strains of isolated Aerococcus spp. showed resistance to erythromycin(26.9%), methicillin(25.4%), kanamycin(22%), and tetracycline(22.4%). The 48 strains of isolated Micrococus spp. showed resistance to tetracycline(27.0%), methicillin(22.9%), erythromycin(22.9%), and kanamycin(20.8%).

• Journal of Life Science
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• v.23 no.1
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• pp.95-101
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• 2013

In this study, plant samples of five species were collected from the Dokdo islands in South Korea. Plant samples such as Asparagus schoberioides, Corydalis platycarpa, Festuca rubra, Sedum oryzifolium, and Setaria viridis were collected from the Dongdo and Seodo. Endophytic fungal strains were isolated from the roots of five plants from the Dokdo islands. Thirty-three fungal strains were isolated from these native plants. All the endophytic fungi were analyzed by internal transcribed spacer (ITS) sequencing (ITS containing ITS1, 5.8s, and the ITS2 region). Waito-c rice seedlings were treated with fungal culture filtrates to test their plant growth-promoting activity. A bioassay of the D-So-1-1 fungal strain isolated from S. oryzifolium confirmed that it has the highest plant growth-promoting activity. All the endophytic fungi belong to four orders: Eurotiales (86%), Capnodiales (3%), Hypocreales (4%), and Incertae sedis (7%). The endophytic fungi were classified as Ascomycota, which contained Aspergillus (12%), Cladosporium (3%), Eurotium (3%), Fusarium (18%), Microsphaeropsis (6%), and Penicillium (58%) at the genus level.

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.303-313
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• 2021

Peanuts in storage were estimated for mycotoxigenic fungi and mycotoxins. Peanut samples collected from storages in Gochang were mainly contaminated with Fusarium (17.2±28.0%), Penicillium (12.4±28.0%), and Aspergillus (8.0±7.6%). Other genera, including Talaromyces, Rhizopus, Rhizoctonia, Trichocladium, Clonostachys, Mucor, Chaetomium, Trametes, Epicoccum, and Humicola, were also found. Although aflatoxins were not detected in the peanut samples, 29 strains of Aspergillus flavus were identified using molecular marker genes. Among them, 17 selected isolates produced aflatoxins in solid culture media ranging from 0.61-187.82 ㎍/kg. All of them could produce both aflatoxin B₁ and B₂ and some (n=5) produced additional G₁, G₂, or both. This study is the first report that A. flavus stains obtained from Korean stored peanut are aflatoxigenic.

• The Korean Journal of Mycology
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• v.43 no.1
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• pp.13-19
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• 2015

Endophytic fungal strains were isolated from 5 aquatic plant species (Trapa japonica, Miscanthus sacchariflorus, Oenanthe javanica, Typha orientalis and Zizania latifolia) native to river wetland of tributary in Nakdong river. Total 34 strains were purely isolated, and then its internal transcribed spacer (ITS) regions were amplified. After that, phylogenetic analysis based on ITS sequences and deduction of diversity indices were done. Fungal isolates were belonged to 17 genera, concretely in Acremonium, Alternaria, Aspergillus, Cladosporium, Emericellopsis, Fusarium, Galactomyces, Leptosphaeria, Microsphaeropsis, Penicillium, Peyronellaea, Phoma, Pseudeurotium, Rhizomucor, Talaromyces, Trematosphaeria and Zalerion. Especially, fungal isolates were distributed intensively in genera Alternaria and Talaromyces. This study deals with the diversity of endophytic fungal species that showing symbiotic relationship with their host aquatic plants.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.28-35
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• 1998

An antimicrobial peptide producing bacterium, Bacillus subtilis A405, was screened and identified among 700 of antagonistic bacteria. The heat-resistant antimicrobial peptide, AMP-405, was purified from the broth culture of B. subtilis A405 through $20{\sim}40%$ ammonium sulfate precipitation and ultrafiltration. The AMP-405 exhibited strong antimicrobial activities against Botrytis cinerea, Cercospora sp., Fusarium oxysporum, Penicillium digitatum, Celletotrichum gloeosporioides, Rhizoctonia solani, Pythium ultimum, Pyricularia oryzae, Escherichia coli, Pseudomonas spp. and Candida albicans. The molecular weight of the peptide was about 3.0 kDa determined by SDS-PAGE, Native-PAGE and Tris-Tricine gradient electrophoresis, and composed of 9 kinds of amino acid such as aspartic acid, glycine, serine, glutamine, valine, leucine, isoleucine, proline, tyrocine. To determine the efficiency of AMP-405 as a potential maintenance of fruits freshness, cherry tomato was srored at $25^{\circ}C$ for 2 weeks after treatment with $50{\mu}g/ml$ of AMP-405 and $10^{5}$ spores/ml of Botrytis cinerea simultaneously. Treatment with AMP-405 resulted in significantly less infection by Botrytis cinerea, than the treatment with tap water as a control.