• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1740-1748
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• 2012

A home-made meju sample contaminated naturally with aflatoxins was used for isolation of fungal strains. Overall, 230 fungal isolates were obtained on dichloran rosebengal chloramphenicol (DRBC) and dichloran 18% glycerol (DG18) agar plates. Morphological characteristics and molecular analysis of a partial ${\beta}$-tubulin gene and the internal transcribed spacer (ITS) of rDNA were used for the identification of the isolates. The fungal isolates were divided into 7 genera: Aspergillus, Eurotium, Penicillium, Eupenicillium, Mucor, Lichtheimia, and Curvularia. Three strains from 56 isolates of the A. oryzae/flavus group were found to be aflatoxigenic A. flavus, by the presence of the aflatoxin biosynthesis genes and confirmatory aflatoxin production by high-performance liquid chromatography (HPLC). The predominant isolate from DRBC plates was A. oryzae (42 strains, 36.2%), whereas that from DG18 was A. candidus (61 strains, 53.5%). Out of the 230 isolates, the most common species was A. candidus (34.3%) followed by A. oryzae (22.2%), Mucor circinelloides (13.0%), P. polonicum (10.0%), A. tubingensis (4.8%), and L. ramosa (3.5%). A. flavus and E. chevalieri presented occurrence levels of 2.2%, respectively. The remaining isolates of A. unguis, P. oxalicum, Eupenicillium cinnamopurpureum, A. acidus, E. rubrum, P. chrysogenum, M. racemosus, and C. inaequalis had lower occurrence levels of < 2.0%.

• The Korean Journal of Mycology
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• v.48 no.4
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• pp.457-473
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• 2020

We investigated the distribution and diversity of fungi in brackish water and soil from the Eulsukdo Island, Geumgang Estuary Bank, Suncheon Bay, Dae-ho Tide Embankment and coastal sand dune in Sinduri and Bu-nam Tide Embankment, Korea. Fungi were isolated from water samples by hand-pumped filtration, and soil samples were collected and diluted. The isolated fungi were incubated in potato dextrose agar at 25℃. A total of 173 fungal strains were isolated from brackish water and identified according to their respective internal transcribed spacer via phylogenetic analysis. The diversity of all fungal strains was analyzed according to diversity indices. The fungal strains belonged to any of 18 taxonomic orders: Pleosporales, Eurotiales, Capnodiales, Hypocreales, Polyporales, Saccharomycetales, Agaricales, Glomerellales, Mucorales, Dothideales, Russulales, Xylariales, Sordariales, Myrmecridiales, Tubeufiales, Onygenales, Cantharellales, and Amphisphaeriales. Cladosporium spp. (20%), Penicillium spp. (19%), and Fusarium sp. (5%) comprised majority of the identified strains. Two species from the fungal isolates were newly identified in Korea: Sarocladium kiliense NNIBRFG3280 and Fusicolla merismoides NNIBRFG23708.

• Biomedical Science Letters
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• v.25 no.4
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• pp.367-371
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• 2019

In this study, the author observed the fungal characteristics of T. verrucosum which is commonly known as the cattle ringworm fungus in the farms of Hoengseong, Gangwon-do. After isolating 20 strains of T. verrucosum from cattle, they were cultured on SDA, PDA media and the fungal characteristics were concluded through visual observation of the colonies, microscopic findings, hair perforation test and urease test. The size of the colonies cultured on SDA media at 37 C was on an average 5 mm at 1 week, 33 mm at 2 weeks, 42 mm at 3 weeks and 58 mm after 4 weeks. Observing the characteristics of the colonies, 17 strains of T. album showing central bold radial folds, 2 strains of T. ochraceum having l throughout the colonies and 1 strain of T. discoides with rapid growth rate and gray-white cotton patterns were found. On microscopic observations of the cultured colonies on SDA, PDA media, macroconidia and microconidia were not found in T. verrucosum and hyphae and chlamydospore were only seen in T. album types. Out of 20 strains of T. verrucosum, hair perforation test was positive on only 3 strains and urease test was positive on all of the 20 strains.

• Journal of Microbiology and Biotechnology
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• v.30 no.11
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• pp.1680-1687
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• 2020

Fungal endophytes are symbiotic microorganisms that are often found in asymptomatic plants. This study describes the genetic diversity of the fungal endophytes isolated from the roots of plants sampled from the west coast of Korea. Five halophytic plant species, Limonium tetragonum, Suaeda australis, Suaeda maritima, Suaeda glauca Bunge, and Phragmites australis, were collected from a salt marsh in Gochang and used to isolate and identify culturable, root-associated endophytic fungi. The fungal internal transcribed spacer (ITS) region ITS1-5.8S-ITS2 was used as the DNA barcode for the classification of these specimens. In total, 156 isolates of the fungal strains were identified and categorized into 23 genera and two phyla (Ascomycota and Basidiomycota), with Dothideomycetes and Sordariomycetes as the predominant classes. The genus Alternaria accounted for the largest number of strains, followed by Cladosporium and Fusarium. The highest diversity index was obtained from the endophytic fungal group associated with the plant P. australis. Waito-C rice seedlings were treated with the fungal culture filtrates to analyze their plant growth-promoting capacity. A bioassay of the Sm-3-7-5 fungal strain isolated from S. maritima confirmed that it had the highest plant growth-promoting capacity. Molecular identification of the Sm-3-7-5 strain revealed that it belongs to Alternaria alternata and is a producer of gibberellins. These findings provided a fundamental basis for understanding the symbiotic interactions between plants and fungi.

• Journal of Microbiology and Biotechnology
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• v.33 no.11
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• pp.1437-1447
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• 2023

A recently bioinformatic analysis of genomic sequences of fungi indicated that fungi are able to produce more secondary metabolites than expected. Despite their potency, many biosynthetic pathways are silent in the absence of specific culture conditions or chemical cues. To access cryptic metabolism, 108 fungal strains isolated from various sites were cultured with or without Streptomyces sp. 13F051 which mainly produces trichostatin analogues, followed by comparison of metabolic profiles using LC-MS. Among the 108 fungal strains, 14 produced secondary metabolites that were not recognized or were scarcely produced in mono-cultivation. Of these two fungal strains, Myrmecridium schulzeri 15F098 and Scleroconidioma sphagnicola 15S058 produced four new compounds (1-4) along with a known compound (5), demonstrating that all four compounds were produced by physical interaction with Streptomyces sp. 13F051. Bioactivity evaluation indicated that compounds 3-5 impede migration of MDA-MB-231 breast cancer cells.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.131-136
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• 2003

Anti-fungal materials producing bacteria were isolated from soil by bennett's agar and actinomycete isola-tion agar medium. The bacterla were identified as synonym of Actinomycetes. Based on the data obtained from its morphological and colony characteristics. The medium for production of anti-fungal materials was YEME (yeast extract 4 g, malt extract l0g, glucose 4 g, D.W 1ι, pH 7.0${\pm}$0.2). The culture conditions were 30$^{\circ}C$, 7 days and 200 rpm in shaking incubator. No. 13, No. 15 and No.28 strains were produced anti-fungal materials against fungal plant pathogens. Specially, The No. 28 strain showed a powerful biopesticide activity and broad spectrum effects of anti -fungal materials on Collectrichum coccodes, Botrytis cinerea, Cladosporium cucumerinum, Didymella bryoniae.

• International Journal of Industrial Entomology and Biomaterials
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• v.37 no.1
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• pp.9-14
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• 2018

Bacterial species, Bacillus amyloliquefaciens and Lactobacillus species (L. sp.5-1), are known to inhibit the growth of pathogenic bacteria and fungi. Metarhizium anisopliae is a pathogenic fungal species which causes fatal damage to P. brevitarsis populations. Therefore, we investigated the inhibitory effect of B. amyloliquefaciens and L. sp. 5-1 on M. anisopliae induced fatality rates in P. brevitarsis. Samples of M. anisopliae-infected sawdust were treated with strain B. amyloliquefaciens KACC10116, strain L. sp. 5-1 KACC19351, and a combination of the two. P. brevitarsis were fed treated sawdust samples, and their subsequent fatality rate was monitored. The fatality rate fell below 1.5% after 10 days and decreased by approximately 40% after 15 days. On average, the fatality rate decreased by 20%, compared to the control. The difference in the decrease in fatality rate between B. amyloliquefaciens treatment and L. sp. 5-1 treatment was not significant. Results indicate that both strains exhibit high anti-fungal activity, which may be useful in environmental purification efforts. These strains may be used for effective prevention of fungal infection in P. brevitarsis.

• The Korean Journal of Mycology
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• v.48 no.1
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• pp.55-61
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• 2020

In this study, we isolated endophytic fungal strains from the rhizoid and the leaf of Mnium heterophyllum and Hypnum plumaeforme, respectively. The isolated strains were identified based on morphological characters and molecular analysis of the internal transcribed spacer, large subunit rDNA, β-tubulin, and RNA polymerase II subunit regions. From the results, we confirmed two endophytic fungal species, Cercophora thailandica, and Biscogniauxia petrensis, which to the best of our knowledge, have not yet been reported in Korea. We further describe the morphological characteristics and the results of the molecular analyses of these isolated fungal strains.

• The Korean Journal of Mycology
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• v.46 no.1
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• pp.22-27
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• 2018

We isolated endophytic fungal strains from the leaves of Abies koreana growing in Korea. The fungal strains were identified as Coleophoma parafusiformis and Coniochaeta ligniaria, based on morphological characteristics and sequence analysis of the internal transcribed spacer region and large subunit region of ribosomal DNA. These species have not been previously reported in Korea. In this study, we report the morphological characteristics and results of phylogenetic analysis of the two novel fungal strains.

• The Plant Pathology Journal
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• v.38 no.4
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• pp.304-312
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• 2022

Boxwood is a representative ornamental shrub that is widely used in landscaping horticulture. After pruning, damaged leaves or stems of boxwoods are unavoidably vulnerable to infection by various plant pathogens. Several boxwood diseases caused by fungi, such as Volutella blight and Macrophoma leaf spot, have been reported worldwide including Republic of Korea. In this study, we isolated and identified fungal pathogens of boxwood diseases that occurred in Korea and characterized their morphological and taxonomic characteristics. Boxwood samples showing blight symptoms were collected in Seoul, Republic of Korea, and the putative fungal pathogens Pseudonectria buxi, P. foliicola, and Neofusicoccum buxi were successfully identified. Investigation of the morphological features of the field isolates, including mycelial growth and conidial morphology, and phylogenetic analysis of multiple DNA barcode loci revealed that there were some morphological and genetic variations among isolates, but all of the analyzed isolates were closely related to the corresponding reference strains. We also found that P. foliicola strains were more virulent than P. buxi, and the N. buxi strains isolated in this study were weak pathogens or saprophytes. The results of our study will contribute to the development of control strategies for boxwood diseases caused by fungi and accelerate research on the complex ecology of boxwood diseases.