• Mycobiology
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• v.47 no.1
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• pp.1-11
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• 2019

The distribution and occurrence of rare ascomycete fungi within freshwater samples in Korea was investigated. Three rare fungal strains, CNUFC-YR537-1, CNUFC-CNUP1-1, and CNUFC-NDR3-1, were isolated using serial dilution method. On the basis of their morphological characteristics and phylogenetic analysis of their internal transcribed spacer regions and 28S rDNA sequences, the three isolates were identified as Acrostalagmus luteoalbus, Bartalinia robillardoides, and Collariella carteri, respectively. To our knowledge, these are the first records of rare genera Acrostalagmus, Bartalinia, and Collariella from Korea, and the first reports of A. luteoalbus, B. robillardoides, and C. carteri from freshwater samples.

• Journal of Environmental Health Sciences
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• v.37 no.6
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• pp.406-417
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• 2011

Objectives: Exposure to bioaerosols in the indoor environment could be associated with a variety adverse health effects, including allergic disease such atopy. The objectives of this study were to assess children's exposure to bioaerosol in home indoor environments and to evaluate the association between atopy and bioaerosol, environmental, and social factors in Ulsan, Korea. Methods: Samples of viable airborne bacteria and fungi were collected by impaction onto agar plates using a Quick Take TM 30 and were counted as colony forming units per cubic meter of air (CFU/$m^3$). Bioaerosols were identified using standard microbial techniques by differential stains and/or microscopy. The environmental factors and possible causes of atopy based on ISAAC (International Study of Allergy and Asthma in Childhood) were collected by questionnaire. Results: The bioaerosol concentrations in indoor environments showed log-normal distribution (p < 0.01). Geometric mean (GM) and geometric standard deviation (GSD) of airborne bacteria and fungi in homes were 189.0 (2.5), 346.1(2.0) CFU/$m^3$, respectively. Indoor fungal levels were significantly higher than those of bacteria (p < 0.001). The concentration of airborne bacteria exceeded the limit recommended by the Korean Ministry of Environment, 800 CFU/$m^3$, in three out of 92 samples (3.3%) from 52 homes. The means of indoor to outdoor ratio (I/O) for airborne bacteria and fungi were 8.15 and 1.13, respectively. The source of airborne bacteria was not outdoors but indoors. GM of airborne bacteria and fungi were 217.6, 291.8 CFU/$m^3$ in the case's home and 162.0, 415.2 CFU/$m^3$ in the control's home respectively. The difference in fungal distributions between case and control were significant (p = 0.004) and the odds ratio was 0.996 (p = 0.027). Atopy was significantly associated with type of house (odds ratio = 1.723, p = 0.047) and income (odds ratio = 1.891, p = 0.041). Some of the potential allergic fungal genera isolated in homes were Cladosporium spp., Botrytis spp., Aspergillus spp., Penicillium spp., and Alternatia spp. Conclusions: These results suggest that there this should be either 'was little' meaning 'basically no significant association was found' or 'was a small negative' mean that an association was found but it was minor. It's a very improtant distinction. Association between airborne fungal concentrations and atopy and certain socioeconomic factors may affect the prevalence of childhood atopy.

• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.13-13
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• 2016

Insects constitute the largest and most diverse group of animals in the world. They also serve as the hosts or nutrient sources for an immense assemblage of pathogens, parasites, and predators. More than 700 fungal species from 100 genera have adopted an entomopathogenic lifestyle. Although entomopathogenic fungi were studied as only biocontrol agents against a variety of pests in various countries, it has been recently focused their additional roles in nature. They are antagonists to/against plant pathogens, endophytes, and possibly even plant growth promoting agents. The potential antimicrobial effect against fungal plant pathogens by an isolate of entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have been reported since late 1990s, but wasn't reported pathogenicity of the isolate against pests. Later, a Canadian Lecanicillium sp. isolate and L. longisporium isolated from Vertalec$^{(R)}$ showed simultaneous control effect against both aphid and cucumber powder mildew. Therefore, the antimicrobial activities of 342 fungi isolates collected from various regions and conditions in Korea were evaluated against plant pathogenic fungus Botrytis cinerea using dual culture technique on agar plate. As a result, 186 isolates (54.4%) shown the antifungal activity against B. cinerea. The culture filtrates of selected fungi completely suppressed the growth of the microorganisms, indicating that suppression was due to the presence of antimicrobial substances in the culture filtrate. Mode of action of these fungi against insect involves the attachment of conidia to the insect cuticle, followed by germination, cuticle penetration, and internal dissemination throughout the insect. During infection process, secreted enzymes, proteinous toxins, and/or secondary metabolites secreted by entomopathogenic fungi can be used to overcome the host immune system, modify host behavior, and defend host resources. Recently, secondary metabolites isolated from entomopathogenic fungi have been reported as potential bioactive substances. Generally, most of bioactive substances produced by entomopathogenic fungi have reported low molecular weight (lower than 1,000 g/mol) as peptide and, in contrast the high molecular weight fungal bioactive substances are rare. Most substances based on entomopathogenic fungi were shown antimicrobial activity with narrow control ranges. In our study we analyzed the antimicrobial substances having antagonistic effects to B. cinerea. Antimicrobial substances in our fungal culture filtrates showed high thermostability, high stability to proteolytic enzymes, and hydrophilicity and their molecular weights were differed from substance. In conclusion, entomopathogenic fungi showed pathogenicity against insect pests and culture filtrate of the fungi also shown to antimicrobial activity. In the future, we can use the entomopathogenic fungi and its secondary metabolites to control both insect pest control and plant pathogenic fungi simultaneously.

• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1149-1161
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• 2014

Cotton plants were sampled and ranked according to their resistance to Verticillium wilt. In total, 642 endophytic fungi isolates representing 27 genera were recovered from Gossypium hirsutum root, stem, and leaf tissues, but were not uniformly distributed. More endophytic fungi appeared in the leaf (391) compared with the root (140) and stem (111) sections. However, no significant difference in the abundance of isolated endophytes was found among resistant cotton varieties. Alternaria exhibited the highest colonization frequency (7.9%), followed by Acremonium (6.6%) and Penicillium (4.8%). Unlike tolerant varieties, resistant and susceptible ones had similar endophytic fungal population compositions. In three Verticillium-wilt-resistant cotton varieties, fungal endophytes from the genus Alternaria were most frequently isolated, followed by Gibberella and Penicillium. The maximum concentration of dominant endophytic fungi was observed in leaf tissues (0.1797). The evenness of stem tissue endophytic communities (0.702) was comparatively more uniform than the other two tissues. Eighty endophytic fungi selected from 27 genera were evaluated for their inhibition activity against highly virulent Verticillium dahliae isolate Vd080 in vitro. Thirty-nine isolates exhibited fungistasis against the pathogen at varying degrees. Seven species, having high growth inhibition rates (${\geq}75%$), exhibited strong antifungal activity against V. dahliae. The antifungal activity of both volatile and nonvolatile metabolites was also investigated. The nonvolatile substances produced by CEF-818 (Penicillium simplicissimum), CEF-325 (Fusarium solani), CEF-714 (Leptosphaeria sp.), and CEF-642 (Talaromyces flavus) completely inhibited V. dahliae growth. These findings deepen our understanding of cotton-endophyte interactions and provide a platform for screening G. hirsutum endophytes with biocontrol potential.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.187-195
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• 1987

Two kinds of heat treatment method for the selective isolation of soil fungi to eliminate the commonest fungi and also to examine the vertical and seasonal distributions of the fungal population were applied to soil samples from two plots around Seoul area. The incubation method at $42^{\circ}C$ and heat treatment at $70^{\circ}C$ were used in this experiment. In the incubation method, the almost all the fungi isolated from two plots were mesophile, while the thermotolerant fungi was Aspergillus fumigatus and thermophilic fungi were Sporotrichum thermophile and Malbranchea pulchella var. sulfrea. The most dominant species isolated by this method was A. fumigatus. Nine genera and fourteen species were isolated from the two plots, and S. thermophile, Talaromyces ucrainicus,Malbranchea pulchella var. sulfrea were new to Korea. From the selection method by heat treatment at $70^{\circ}C$, ten genera and twenty species were isolated. Among these, the most fungi were also mesophile and thermotolerant fungus was A. fumigatus. The most dominant species isolated by this method was T. stipitatus, Talaromyces helicus var. major, Emericella nidulans var. nidulans, Chaetomium subspirale and Neosartorya fisheri var. fisheri were new to Korea. From the two isolation methods, it was found that the total number of soil fungi and frequency of species appeared including dominant ones were the highest at the soils of upper layer while the lowest at the soils of lower layer in its vertical distribution.

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.122-133
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• 2018

The Seonamsa temple is located on steep terrain surrounded by forests and valleys, and is a place that the temple is scared of biological damage because it has high humidity and low wind levels. Therefore, we investigated a concentration and diversity of airborne fungi in indoor and outdoor by collecting air each season. The outdoor fungal load was far higher in spring ($276CFU/m^3$), autumn ($196CFU/m^3$), summer ($128CFU/m^3$) than in winter ($24CFU/m^3$). The lowest located Jijangjeon and upper located Wontongjeon showed the highest distribution of $337.4CFU/m^3$ in summer and $333.4CFU/m^3$ in autumn, respectively. Summer is the season with large variations in the concentration of airborne fungi between indoor and outdoor, a concentration of airborne fungi in indoor was maximum three times higher than these in outdoor with $128CFU/m^3$. Although the most fungi were collected in spring, fungal diversity was richer in summer and autumn with 28 genera 45 species and 25 genera 47 species, respectively. In particular, the concentration of airborne fungi was the most highest in all sampling sites in autumn, of which Ascomycota members accounted for 86% and Cladosporium genus was dominated. The most kind of Penicillium (16 species) was mainly distributed in indoor air in summer, autumn and winter.

• Mycobiology
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• v.46 no.2
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• pp.85-91
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• 2018

Endophytic fungi strains (n = 81) were isolated from the leaves, barks, and fruits of Camellia oleifera from Hunan province (China) to delineate their species composition and potential as biological control agents of C. oleifera anthracnose. The fungi were identified by morphological and phylogenetic analyses. Fungal colonization rates of the leaves, barks, and fruits were 58.02, 27.16, and 14.81%, respectively. The isolates were identified as 14 genera, belonging to two subdivisions, Deuteromycotina and Ascomycotina; 87.65% of all isolates belonged to Deuteromycotina. The dominant species, occurring with a high relative frequency, were Pestalotiopsis sp. (14.81%), Penicillium sp. (14.81%), and Fusarium sp. (12.35%). The Simpson's and Shannon's diversity indices revealed the highest species diversity in the leaves, followed by the barks and fruits. The similarity index for the leaves versus barks comparison was the highest, indicating that the number of endophytic fungal species shared by the leaves and barks was higher than barks and fruits or leaves and fruits. Based on the results of dual culture experiments, only five strains exhibited antifungal activity against C. oleifera anthracnose pathogen, with isolate ty-64 (Oidium sp.) generating the broadest inhibition zones. Our results indicate that the endophytes associated with C. oleifera could be employed as natural agents controlling C. oleifera anthracnose.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.978-987
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• 2015

Aluminum (Al) toxicity is one of the greatest limitations to agriculture in acid soils, particularly in tropical regions. Arbuscular mycorrhizal fungi (AMF) can supply plants with nutrients and give protection against Al toxicity. The aim of this work was to evaluate the effects of soil liming (i.e., reducing Al saturation) on the AMF community composition and structure in the roots of maize lines contrasting for Al tolerance. To this end, we constructed four 18S rDNA cloning libraries from L3 (Al tolerant) and L22 (Al sensitive) maize lines grown in limed and non-limed soils. A total of 790 clones were sequenced, 69% belonging to the Glomeromycota phylum. The remaining sequences were from Ascomycota, which were more prominent in the limed soil, mainly in the L3 line. The most abundant AM fungal clones were related to the family Glomeraceae represented by the genera uncultured Glomus followed by Rhizophagus and Funneliformis. However, the most abundant operational taxonomic units with 27% of the Glomeromycota clones was affiliated to genus Racocetra. This genus was present in all the four libraries, but it was predominant in the non-limed soils, suggesting that Racocetra is tolerant to Al toxicity. Similarly, Acaulospora and Rhizophagus were also present mostly in both lines in non-limed soils. The community richness of AMF in the non-limed soils was higher than the limed soil for both lines. The results suggest that the soil Al saturation was the parameter that mostly influences the AMF species composition in the soils in this study.

• Microbiology and Biotechnology Letters
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• v.7 no.1
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• pp.15-21
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• 1979

In order to find out a reliable chemical indicator which can be used to tell whether rice, during storage, is invaded by fungi or not, 90 percent milled rice (Tongil) was stored at 26$^{\circ}C$ for 4 weeks and weekly analyzed for changes in several chemical components. The results were as follows : 1) Of several genera of fungi (Aspergillus sp., Penicillium sp., and Rhizopus sp.) observed in stored rice after surface disinfection, Aspergillus sp. were the most frequent fungi. 2) Chitin content in the rice was 25 ug/g at the beginning of the experiment and increased proportionly with moisture content of the storedrice to become 1980 ug/g at 26.9％ moisture after 4 weeks. 3) Non-reducing sugartended to decrease with increasing moisture content and or prolonged period. 4) Fat acidity showed a tendency of increase with rise in moisture content of the stared rice. Consequently, changes in chitin content can be mployed as a reliable measure to evaluate the quality of stored rice in connection with fungal invasion.

• Mycobiology
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• v.44 no.3
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• pp.121-130
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• 2016

Recently, the Fusarium genus has been narrowed based upon phylogenetic analyses and a Fusarium-like clade was adopted. The few species of the Fusarium-like clade were moved to new, re-installed or existing genera or provisionally retained as "Fusarium." Only a limited number of reference strains and DNA marker sequences are available for this clade and not much is known about its actual species diversity. Here, we report six strains, preserved by the Belgian fungal culture collection BCCM/IHEM as a Fusarium species, that belong to the Fusarium-like clade. They showed a slow growth and produced pionnotes, typical morphological characteristics of many Fusarium-like species. Multilocus sequencing with comparative sequence analyses in GenBank and phylogenetic analyses, using reference sequences of type material, confirmed that they were indeed member of the Fusarium-like clade. One strain was identified as "Fusarium" ciliatum whereas another strain was identified as Fusicolla merismoides. The four remaining strains were shown to represent a unique phylogenetic lineage in the Fusarium-like clade and were also found morphologically distinct from other members of the Fusarium-like clade. Based upon phylogenetic considerations, a new genus, Pseudofusicolla gen. nov., and a new species, Pseudofusicolla belgica sp. nov., were installed for this lineage. A formal description is provided in this study. Additional sampling will be required to gather isolates other than the historical strains presented in the present study as well as to further reveal the actual species diversity in the Fusarium-like clade.