• Bulletin of the Korean Chemical Society
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• 제27권5호
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• pp.779-782
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• 2006

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 춘계학술대회 및 임시총회
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• pp.14-14
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• 2015

Fungi are of particular interest due to their capacity to produce an extensive array of secondary metabolites. While many secondary metabolites have no known functions to the producing fungal organisms, these metabolites have tremendous importance to humans with beneficial (e.g., antibiotics) or detrimental (e.g., mycotoxins) properties. In this study, two important filamentous fungi, Fusarium verticillioides and Mycosphaerella graminicola were selected as target species and the genes regulatory functions on the biosynthesis of secondary metabolisms were studied. Functional genomics including forward and reverse genetics, and proteomics were utilized to better understand the complex secondary metabolism regulations in both F. verticillioides and M. graminicola. Identified genes in either F. verticillioides or M. graminicola background were CPP1 (a putative protein phosphatase gene), GAC1 (encoding a GTPase activating protein), MCC1(encoding c-type cyclin), and the velvet gene, MVE1. Our data suggest that there are diverse regulatory genes on fungal secondary metabolites with distinct or overlapping functional roles.

• International Journal of Industrial Entomology and Biomaterials
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• 제26권2호
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• pp.89-94
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• 2013

Entomopathogenic fungal species have been investigated for their potential use as biological control agents owing to their natural role as insect pathogens. These fungi produce a wide range of secondary metabolites with high therapeutic values, such as antibiotics and cytotoxic substances. To evaluate the antibacterial activity of entomopathogenic fungi, 10 isolates from Korean soil were selected and tested for their activity against Escherichia coli by using fungal culture filtrates. Antibacterial activity was assessed using a two-step process: (1) a screening assay for the selection of fungal isolates and (2) a quantitative assay to evaluate the activity of select fungi. Although 4 fungal isolates were selected through the screening assay, only 3 fungal isolates, from Beauveria bassiana and Metarhizium anisopliae, showed high antibacterial activity according to the quantitative assay. The antibacterial activity of selected fungal culture filtrates was stable when exposed to heat and proteolytic enzyme treatments, which indicated that the antibacterial compound is not a protein. These entomopathogenic fungal metabolites might be useful as a source for bacterial control and in the pharmaceutical industry.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1695-1698
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• 2010

Protulactones A (1) and B (2), two new polyketide-derived fungal metabolites, have been isolated from an EtOAc extract of the marine-derived fungus Aspergillus sp. SF-5044 by various chromatographic methods. The structures of 1 and 2 were mainly determined by analysis of the NMR spectroscopic data and MS data, along with chemical methods such as Mosher method. Protulactones A (1) and B (2) are new members of polyketide-derived secondary metabolites, possessing unique ring systems among the fungal metabolites produced by the genus Aspergillus.

• 한국식품과학회지
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• 제38권2호
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• pp.262-267
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• 2006

본 논문은 새로운 항암소재를 검색하기 위하여 식품으로부터 곰팡이를 분리하고 그 대사산물을 이용하여 수종의 암세포주의 생육을 대한 억제 물질을 탐색하고자 하며, 이를 바탕으로 새로운 항생물질 연구의 기초자료를 확보하고 결과물의 응용도를 모색하고자 실험을 수행하였다. 식품으로부터 총 72종의 곰팡이를 분리 하였고, 전면 및 후면의 색, 모양. 성장속도에 따라 4가지 group로 나누어 실험에 사용하였다. 그리고 그 대사산물(배양무, 균체)을 ethly acetate로 추출하여, 총 6종의 암세포주에 대하여 MTT assay을 실험하였다. 그 ruf과 A, B, C, D group 중 D group에서 가장 높은 증식 억제를 확인 하였으며, D4의 증식억제 효과가 가장 높음을 확인하였다. 위암 세포주인 KATO III, AGS, SUN-668에 대한 증식억제 효과는 30-98%로 나타났으며, 간암 세포주인 Hepa1c1c7, HepG2에는 10-98%, 유방암 세포주인 MDA-MB-231에 대해서는 25-90%의 증식억제 효과를 확인하였다. 배양물과 균체의 항암성은 개체에 따라 약간의 차이는 있으나, 배양물이 대부분 우수한 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제33권11호
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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.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1206-1211
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• 2013

The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory fungal metabolites, the organic extracts of several fungal species isolated from marine environments were found to exhibit significant inhibitory effects, and the bioassay-guided investigation of these extracts resulted in the isolation of fructigenine A (1), cyclopenol (2), echinulin (3), flavoglaucin (4), and viridicatol (5). The structures of these compounds were determined mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 10.7, 30.0, 29.4, 13.4, and 64.0 ${\mu}M$, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compounds 1 and 5 suggested that compound 1 inhibited PTP1B activity in a noncompetitive manner, whereas compound 5 inhibited PTP1B activity in a competitive manner.

• Journal of Microbiology
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• 제40권4호
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• pp.289-294
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• 2002

The fungal strain SW-3 having antimicrobial activity was isolated from soil of crucified plants in Pocheon, Kyungki-Do, Korea. Strain SW-3 was identified as Alternaria brassicicola by its morphological characteristics, and confirmed by the analysis of the 18S gene and ITS regions of rDNA. The fungus showed a similarity of 99% with Alternaria brassicicola in the 18S rDNA sequence analysis. A. brassicicola has been reported to produce an antitumor compound, called depudecin. We found that strain SW-3 produced antimicrobial metabolites, in addition to depudecin, during sporulation under different growth conditions. The metabolite of the isolated fungus was found to have strong antifungal activity against Microsporium canis and Trichophyton rubrum, and antibacterial activity against Staphylococcus aureus and Pseudomonas aerogenes. The amount and kind of metabolites produced by the isolate were affected by growth conditions such as nutrients and growth periods.

• Mycobiology
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• 제30권4호
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• pp.233-239
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• 2002

The main aim of this study is to evaluate the efficiency of two biologically active compounds(Strom and F-760) in control of wheat root rot disease and its causal organisms. Fusarium graminearum, F. oxysporum, F. solani and Bipolaris sorokiniana were used as target organisms. In vitro, the two compounds showed fungicidal effect on all investigated pathogens resulted in suppression of radial growth and mycelial dry weight of them. Under greenhouse conditions, treatment of wheat grains with either Strom or F-760 before cultivation significantly reduced the percent of disease distribution as well as the mean disease rating of plants in both seedling and flowering stages. Fresh and dry weights of plants as well as water maintenance capacity were increased as the result of applying these compounds as seed dressing. Also data showed that the membrane stability of plants was injured as a result of infection with all investigated organisms, while this injury was alleviated when F-760 and Strom were applied. The $K^+$ efflux and the leakage of UV absorbing metabolites was stimulated with fungal infection. However, F-760 and Storm treatment partially retarded the stimulatory effect on leakage of $K^+$ and UV-absorbing metabolites of fungal infected plants. On the other side, the fungal infection had inhibitory effects on pigment fractions(chlorophyll a, b, and carotenoids) biosynthesis in wheat leaves. This retarding effect was partially or completely alleviated as the grains were treated with the applied compounds.

• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1416-1423
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• 2013

The metabolomic profile of the anaerobic fungus Piromyces sp. F1, isolated from the rumen of goats, and how this is affected by the presence of naturally associated methanogens, was analyzed by nuclear magnetic resonance spectroscopy. The major metabolites in the fungal monoculture were formate, lactate, ethanol, acetate, succinate, sugars/amino acids and ${\alpha}$-ketoglutarate, whereas the co-cultures of anaerobic fungi and associated methanogens produced citrate. This is the first report of citrate as a major metabolite of anaerobic fungi. Univariate analysis showed that the mean values of formate, lactate, ethanol, citrate, succinate and acetate in co-cultures were significantly higher than those in the fungal monoculture, while the mean values of glucose and ${\alpha}$-ketoglutarate were significantly reduced in co-cultures. Unsupervised principal components analysis revealed separation of metabolite profiles of the fungal mono-culture and co-cultures. In conclusion, the novel finding of citrate as one of the major metabolites of anaerobic fungi associated with methanogens may suggest a new yet to be identified pathway exists in co-culture. Anaerobic fungal metabolism was shifted by associated methanogens, indicating that anaerobic fungi are important providers of substrates for methanogens in the rumen and thus play a key role in ruminal methanogenesis.