• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1027-1036
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• 2020

Stipa purpurea is a unique and dominant herbaceous plant species in the alpine steppe and meadows on the Qinghai-Tibet Plateau (QTP). In this work, we analyzed the composition and diversity of the culturable endophytic fungi in S. purpurea according to morphological and molecular identification. Then, we investigated the bioactivities of these fungi against plant pathogenic fungi and 1-aminocyclopropane-1-carboxylate deaminase (ACCD) deaminase activities. A total of 323 fungal isolates were first isolated from S. purpurea, and 33 fungal taxa were identified by internal transcribed spacer primers and grouped into Ascomycota. The diversity of endophytic fungi in S. purpurea was significantly higher in roots as compared to leaves. In addition, more than 40% of the endophytic fungi carried the gene encoding for the ACCD gene. The antibiosis assay demonstrated that 29, 35, 28, 37 and 34 isolates (43.9, 53.1, 42.4, 56.1, and 51.5%) were antagonistic to five plant pathogenic fungi, respectively. Our study provided the first assessment of the diversity of culture-depending endophytic fungi of S. purpurea, demonstrated the potential application of ACCD activity and antifungal activities with potential benefits to the host plant, and contributed to high biomass production and adaptation of S. purpurea to an adverse environment.

• The Korean Journal of Mycology
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• v.49 no.4
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• pp.497-505
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• 2021

Endophytic fungal strains were isolated from leaves, stems, and roots of Angelica gigas. The fungal strains were identified based on their morphological characteristics and molecular analysis of the internal transcribed spacer (ITS). A total 35 species of endophytic fungi were identified. The diversity between the endophytic fungal communities differed depending on the tissues of A. gigas. The isolated endophytic fungi were screened for antifungal activity against a pathogenic fungus, Phoma sp. Y11, using a dual culture method. Fourteen species of endophytic fungi showed the standout inhibition effect against the Y11 strain. The results suggest that the endophytic fungi isolated from A. gigas could be used as a biological control agent against leaf spot disease of A. gigas.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.731-738
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• 2019

Endophytic fungi are an important component of plant microbiota, and have the excellent capacity for producing a broad variety of bioactive metabolites. These bioactive metabolites not only affect the survival of the host plant, but also provide valuable lead compounds for novel drug discovery. In this study, forty-two endophytic filamentous fungi were isolated from Ficus elastica leaves, and further identified as seven individual taxa by ITS-rDNA sequencing. The antimicrobial activity of these endophytic fungi was evaluated against five pathogenic microorganisms. Two strains, Fes1711 (Penicillium funiculosum) and Fes1712 (Trichoderma harzianum), displayed broad-spectrum bioactivities. Our following study emphasizes the isolation, identification and bioactivity testing of chemical metabolites produced by T. harzianum Fes1712. Two new isocoumarin derivatives (1 and 2), together with three known compounds (3-5) were isolated, and their structures were elucidated using NMR and MS. Compounds 1 and 2 exhibited inhibitory activity against Escherichia coli. Our findings reveal that endophytic fungi from the rubber tree F. elastica leaves exhibit unique characteristics and are potential producers of novel natural bioactive products.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.231-241
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• 1998

To assess biological indoor air quality in hospital, concentrations of viable airborne microbes were determined at intensive care unit(ICU), patient room (PR), outpatient waiting room(OPWR) in hospitals of large(1000 beds), middle(500 beds), small(100 beds) hospitals, respectively. Gram positive bacteria, gram negative bacteria, fungi were sampled using suctional sampling method by RCS sampler (Reuter centrifugal air sampler) and RCS GK-A agar plate. In gram positive bacteria groups, CNS(Coagulase Negative Staphylococcus), Micrococcus, Lactobacillus, S. aureus, Enterococcus, St. viridans identified. In gram negative bacteria groups, A. baumannii, Kl. peumoniae and E. coli were identified, and Penicillium was identified in fugi groups. Results of the study were as follows. 1. The highest concentrations of airborne microbes was $971CFU/m^3$ at 5:00 PM in small hospital patient room, and average concentrations of airborne microbes in large, middle and small hospitals were $282CFU/m^3$, $289CFU/m^3$ and $625CFU/m^3$, respectively. Average concentrations of airborne microbes in office(control) was $90CFU/m^3$. Thus, the small hospital showed the worst condition. 2. Representatives of 8 different genera were identified in 150 samples. The most frequently isolated organisms were Staphylococcus (73.0%), Micrococcus (20.7%) and Lactobacillus (4.7%), respectively. Pathogenic microbes isolated were A. baumannii, E. coli, Enterococcus, Kl. peumoniae, S. aureus, St. viridans and Penicillium as fungi. In office, no pathogenic microbes were identified. Average concentrations of airborne pathogenic microbes in large, middle and small hospital were $5CFU/m^3$ (2%), $11CFU/m^3$ (4%) and $12CFU/m^3$ (2%), respectively. Thus, condition in a large hospital was better than those in a middle and a small hospital.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.889-893
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• 2012

Appressorium is a specialized infection structure of filamentous pathogenic fungi and plays an important role in establishing a pathogenic relationship with the host. The Egh16/Egh16H family members are involved in appressorium formation and pathogenesis in pathogenic filamentous fungi. In this study, a homolog of Egh16H, Magas1, was identified from an entomopathogenic fungus, Metarhizium acridum. The Magas1 protein shared a number of conserved motifs with other Egh16/Egh16H family members and specifically expressed during the appressorium development period. Magas1-EGFP fusion expression showed that Magas1 protein was not localized inside the cell. Deletion of the Magas1 gene had no impact on vegetative growth, conidiation and appressorium formation, but resulted in a decreased mortality of host insect when topically inoculated. However, the mortality was not significant between the Magas1 deletion mutant and wild-type treatment when the cuticle was bypassed by injecting conidia directly into the hemocoel. Our results suggested that Magas1 may influence virulence by affecting the penetration of the insects' cuticle.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.355-367
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• 2020

One hundred representative species of fungi in Korea were selected and their Korean names were proposed to increase interest in fungi among Korean people. This task was performed under the supervision of the Committee of Mycological Terms, under the Korean Society of Mycology. First, the committee established the criteria for selecting 100 representative species of fungi in Korea and then selected the candidate fungal species accordingly. To ensure the uniformity and stability of Korean fungal names, the principle of naming fungi in Korean was established, and the candidate Korean fungal names were presented accordingly. Finally, the candidate Korean fungal names were posted online to collect opinions of the members of the Korean Society of Mycology. The candidate Korean names of the plant pathogenic fungi and mushrooms were reviewed by the Korean Society of Plant Pathology and the Korean Society of Mushroom Science, respectively. After their opinions were considered, the Korean names for 100 representative fungi in Korea were finally determined. The 100 fungi comprised 41 common molds and yeasts, 28 plant pathogenic fungi, and 31 mushrooms.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.603-613
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• 2019

This study was carried out to examine the antagonistic effect against phytopathogenic fungi of isolated strains from soil samples collected from Busan, Changwon, and Jeju Island: Botrytis cinerea, Colletotrichum acutatum, Corynespora cassiicola, Fusarium sp., Rhizoctonia solani, Phytophthora capsici, and Sclerotinia sclerotiorum. According to results of our studies, isolated strains showed an antagonistic effect against phytopathogenic fungi. Such an antagonistic effect against phytopathogenic fungi is seen due to the production of siderophores, antibiotic substances, and extracellular amylase, cellulase, protease, and xylanase enzyme activities. Extracellular enzymes produced by isolated strains were significant, given that they inhibited the growth of phytopathogenic fungi by causing bacteriolysis of the cell wall of plant pathogenic fungi. This is essential to break down the cell wall of plant pathogenic fungi and thus help plant growth by converting macromolecules, which cannot be used by the plant for growth, into small molecules. In addition, they are putative candidates as biological agents to promote plant growth and inhibit growth of phytopathogenic fungi through nitrogen fixation, indole-3-acetic acid production, siderophore production, and extracellular enzyme activity. Therefore, this study suggests the possibility of using Bacillus subtilis ANGa5, Bacillus aerius ANGa25, and Bacillus methylotrophicus ANGa27 as new biological agents, and it is considered that further studies are necessary to prove their effect as novel biological agents by standardization of formulation and optimization of selected effective microorganisms, determination of their preservation period, and crop cultivation tests.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.651-658
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• 2010

Garcinia is commonly found in Malaysia, but limited information is available regarding endophytic fungi associated with this plant. In this study, 24 endophytic fungi were successfully recovered from different parts of two Garcinia species. Characterization of endophytic fungi was performed based on the conserved internal transcribed spacer (ITS) region sequence analysis and the antimicrobial properties. Results revealed that fruits of the plant appeared to be the highest inhabitation site (38%) as compared with others. Glomerella sp., Guignardia sp., and Phomopsis sp. appeared to be the predominant endophytic fungi group in Garcinia mangostana and Garcinia parvifolia. Phylogenetic relationships of the isolated endophytic fungi were estimated from the sequences of the ITS region. On the other hand, antibacterial screening showed 11 of the isolates possessed positive response towards pathogenic and nonpathogenic bacteria. However, there was no direct association between certain antibacterial properties with the specific genus observed.

• Mycobiology
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• v.34 no.4
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• pp.185-190
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• 2006

Endophytic fungi were isolated from healthy leaf and root samples of Taraxacum coreanum. Of the 72 isolates recovered, 39 were from leaves and 33 from roots with an isolation frequency of 54% and 46%, respectively. Based on ITS sequence analysis, 72 isolates were classified into 19 genera of which 17 were under the phylum Ascomycota and 2 were under Basidiomycota. Diverse genera were found and Alternaria, Cladosporium, Fusarium and Phoma were dominant. Out of 19 genera, Apodus, Ceriporia, Dothideales, Leptodontidium, Nemania, Neoplaconema, Phaeosphaeria, Plectosphaerella and Terfezia were new to Korea. Seventy two isolates were screened for antifungal activity, of which 10 isolates (14%) were found active at least against one of the tested fungi. Isolate 050603 had the widest antifungal spectra of activity, and isolates 050592 and 050611 were active against three plant pathogenic fungi.

• KSBB Journal
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• v.31 no.4
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• pp.312-314
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• 2016

This study was carried out to determine the antifungal activity of $SeO_2$ against pathogenic fungus, Candida albicans. Concentration-dependent Inhibitory activity of $SeO_2$ against C. albicans was shown. When $400{\mu}g/disc$ of $SeO_2$ was tested, the inhibition size ranged from 20.7 to 26.8 mm (avg. 23.4 mm). MIC values of $SeO_2$ against cell growth of C. albicans ranged from 50 to $100{\mu}g/mL$ (avg. $70{\mu}g/mL$). These results could be applied to antibiotics-resistant C. albicans and other pathogenic fungi.