• Korean Journal of Microbiology
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• v.4 no.2
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• pp.11-14
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• 1966

The deterioration of cellulosic materials due to the growth of mildew causes enormous loss to us. It is, therefore, necessary to give adequate protectional treatment against mildew spoilage on cellulosic materials. In this study, fourteen chemicals were treated to the strain of Chaetomium globosum A.T.C.C., then phenyl mercuric acetate (P.M.A) was proved to be a most effective fungicide out of various chemicals. Another chemicals, such as Na-pentachlorophenolate, tuget, $\alpha$-naphthol, caprylic acid and orthocidc were also proved to be effective mildew-proofing agents.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.241-242
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• 2001

Chitosan, a deacetylated derivative of chitin, is one of the abundant resources, and its biological properties such as antibactierial activity, hypocholesterolemic activity, and hypertensive action are remarked. However, increasing attention has recently been yen to converting chitosan to its oligosaccharides because they possess various functional properties like antitumor activity, immune-enhancing effects, enhancing protective effects against infection with some pathogens in mice, antifungal activity, and antimicrobial activity (Jeon et al., 2001). (omitted)

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.37-44
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• 1999

Two sulphamide (dichlofluanid and tolylfluanid) and three dicarboximide fungicides (iprodione, vinclozolin, procymidone) were used to investigate the correlation between in vitro antifungal activities and in vivo disease controlling activities against Botrytis cinerea, a causal agent of tomato gray mold and to develop efficient in vitro assays. They controlled effectively the development of tomato gray mold disease in vivo and their controlling activities were similar one another. However, several in vitro assays revealed that their in vitro antifungal activities were quite different between sulphamide and dicarboximide fungicides; the formers showed stronger inhibition activities for spore germination than the latters, whereas the formers inhibited mycelial growth less severely than the latters. The results indicate that the fungicides having different modes of action can show different in vitro antifungal activities according to in vitro assays, even if they have similar in vivo disease controlling activities. On the other hand, two rapid and efficient in vitro assays named Microtiter plate methods I (MPM I) and II (MPM II) were developed for the evaluation of fungicides for inhibitory activities against spore germination and mycelial growth of B. cinerea, respectively. The antifungal activities of five fungicides of two chemical groups in MPM I and II were correlated with the inhibitory activities against spore germination and mycelial growth using solid media, respectively.

• Journal of Life Science
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• v.8 no.4
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• pp.421-425
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• 1998

The antifungal activity of polygodial, which was isolated from Polygonum hydropiper used as a hot spice in Japan, was investigated through measuring its MICs and against food-contaminants including 4 strains of Saccharomyces cerevisiae, 3 strains of Zygosaccharomyces species, and 5 strains of Aspergillus species. All yeast-like fungi exhibited strong antifungal susceptivilities with MICs and MFCs below 3.13${\mu}g$/ml. Strains of Aspergillu species showed moderate with MIC of 25-50${\mu}g$/ml and MFC of 50-100${\mu}g$/ml. However these strains to sorbic acid, as already known, revealed very weak with MICs of 200-800${\mu}g$/ml and MFCs above 1600${\mu}g$/ml. In addition, effects of various pHs and temperatures on the antifungal activity of polygodial were tested against S. cerevisiae. At $4^{\circ}C$, the fungicidal activity of polygodial gradually increased with incubation time and reached the maximum(MFC of 3. 13${\mu}g$/ml) in 5 hours. At temperatures in the range of 30-$45^{\circ}C$, the activity of polygodial increased in proportion to temperature rise and in particular at $45^{\circ}C$ was possible with the concentration of 0.1${\mu}g$/ml. mOn the other hand, medium pH was also identified to affect the antifungal activity of polygodial. Namely, compared to neutral (pH7), acidic(pH 3) and basic(pH 9) medium synergized its activity (MIC and MFC) to 8- and 2- fold, respectively.

• Korean Journal of Microbiology
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• v.3 no.1
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• pp.18-23
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• 1965

It seems like that the characteristics and drug-resistances of fungi are respectively different in various circumstances. Scores of chemicals were applicated to the leather-fungi in this study. M-dinitrobenzene, 2, 4-dinitrochlorobenzene and phenyl mercuric acetate inhibited the growth of Aspergilli which were isolated from Korean-leather. The minimum fungicidal limits of p-nitrophenol, 8-hydroxyquinoline and sodium-pentachlorophenolate against the Korean-originated strains are different from that of other country. In the mass-screening of fungicides, artificial "Leather-extracts media" have been designed and used, and the media contributed to screening-tests. Fat and oils which are the materials of fat-liquoring in leather manufacture affects the drugresistance of the leather-fungi. It is found that the accelerating-method on malt-agar plate is effective to determinate the fungicidal action of chemicals in short time.hort time.

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1377-1381
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• 2014

In order to discover and develop novel signaling inhibitors from plants, a screening system was established targeting the two-component system of Cryptococcus neoformans by using the wild type and a calcineurin mutant of C. neoformans, based on the counter-regulatory action of high-osmolarity glycerol (Hog1) mitogen-activated protein kinase and the calcineurin pathways in C. neoformans. Among 10,000 plant extracts, that from Harrisonia abyssinica Oliv. exhibited the most potent inhibitory activity against C. neoformans var. grubii H99 with fludioxonil. Bioassay-guided fractionation was used to isolate two bioactive compounds from H. abyssinica, and these compounds were identified as chebulagic acid and chebulanin using spectroscopic methods. These compounds specifically inhibited the calcineurin pathway in C. neoformans. Moreover, they exhibited potent antifungal activities against various human pathogenic fungi with minimum inhibitory concentrations ranging from 0.25 to over $64{\mu}g/ml$.

• Journal of Microbiology and Biotechnology
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• v.20 no.10
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• pp.1397-1402
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• 2010

Papyriflavonol A (PapA), a prenylated flavonoid [5,7,3',4'-tetrahydroxy-6,5'-di-(${\gamma},{\gamma}$-dimethylallyl)-flavonol], was isolated from the root barks of Broussonetia papyrifera. Our previous study showed that PapA has a broad-spectrum antimicrobial activity against pathogenic bacteria and fungi. In this study, the mode of action of PapA against Candida albicans was investigated to evaluate PapA as an antifungal agent. The minimal inhibitory concentration (MIC) values were 10~25 ${\mu}g/ml$ for C. albicans and Saccharomyces cerevisiae, Gram-negative bacteria (Escherichia coli and Salmonella typhimurium), and Gram-positive bacteria (Staphylococcus epidermidis and Staphylococcus aureus). The kinetics of cell growth inhibition, scanning electron microscopy, and measurement of plasma membrane florescence anisotrophy revealed that the antifungal activity of PapA against C. albicans and S. cerevisiae is mediated by its ability to disrupt the cell membrane integrity. Compared with amphotericin B, a cell-membrane-disrupting polyene antibiotic, the hemolytic toxicity of PapA was negligible. At 10~25 ${\mu}g/ml$ of MIC levels for the tested strains, the hemolysis ratio of human erythrocytes was less than 5%. Our results suggest that PapA could be a therapeutic fungicidal agent having potential as a broad spectrum antimicrobial agent.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.38-46
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• 2009

Lichen-forming fungi (LEF) were isolated from 67 Hungarian lichen species from ascospores or thallus fragments. LFF were successfully isolated from 26 species with isolation rate of 38.8%. Of the total number of isolation from ascospores (27 species) and thallus fragments (40 species), 48% and 32.5% of the species were successfully isolated, respectively. Comparison of rDNA sequences of ITS regions between the isolated LFF and the original thallus confirmed that all the isolates originated from the thallus fragments were LEF. The following 14 species of LEF were newly isolated in this study; Acarospora cervina, Bacidia rubella, Cladonia pyxidata, Lasallia pustulata, Lecania hyaline, Lecanora argentata, Parmelina tiliacea, Parmotrema chinense, Physconia distorta, Protoparmeliopsis muralis, Ramalina pollinaria, Sarcogyne regularis, Umbilicaria hirsuta, Xanthoparmelia conspersa and X. stenophylla. Antifungal activity of the Hungarian LFF was evaluated against plant pathogenic fungi of Colletotrichum acutatum, C. coccodes and C. gloeosporioides, causal agent of anthracnose on hot pepper. Among the 26 isolates, 11 LFF showed more than 50% of inhibition rates of mycelial growth of at least one target pathogen. Especially, LFF of Evernia prunastri, Lecania hyalina and Lecanora argentata were remarkably effective in inhibition of mycelial growth of all the tested pathogens with antibiotic mode of action. On the other hands, five isolates of Cladonia furcata, Hypogymnia physodes, Lasallia pustulata, Ramalina fastigiata and Ramalina pollinaria exhibited fungal lytic activity against all the three pathogens. Among the tested fungal pathogens, C. coccodes seemed to be most sensitive to the LFF. The Hungarian LFF firstly isolated in this study can be served as novel bioresources to develop new biofungicides alternative to current fungicides to control hot pepper anthracnose pathogenic fungi.

• Biomolecules & Therapeutics
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• v.29 no.2
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• pp.234-247
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• 2021

We used a heterozygous gene deletion library of fission yeasts comprising all essential and non-essential genes for a microarray screening of target genes of the antifungal terbinafine, which inhibits ergosterol synthesis via the Erg1 enzyme. We identified 14 heterozygous strains corresponding to 10 non-essential [7 ribosomal-protein (RP) coding genes, spt7, spt20, and elp2] and 4 essential genes (tif302, rpl2501, rpl31, and erg1). Expectedly, their erg1 mRNA and protein levels had decreased compared to the control strain SP286. When we studied the action mechanism of the non-essential target genes using cognate haploid deletion strains, knockout of SAGA-subunit genes caused a down-regulation in erg1 transcription compared to the control strain ED668. However, knockout of RP genes conferred no susceptibility to ergosterol-targeting antifungals. Surprisingly, the RP genes participated in the erg1 transcription as components of repressor complexes as observed in a comparison analysis of the experimental ratio of erg1 mRNA. To understand the action mechanism of the interaction between the drug and the novel essential target genes, we performed isobologram assays with terbinafine and econazole (or cycloheximide). Terbinafine susceptibility of the tif302 heterozygous strain was attributed to both decreased erg1 mRNA levels and inhibition of translation. Moreover, Tif302 was required for efficacy of both terbinafine and cycloheximide. Based on a molecular modeling analysis, terbinafine could directly bind to Tif302 in yeasts, suggesting Tif302 as a potential off-target of terbinafine. In conclusion, this genome-wide screening system can be harnessed for the identification and characterization of target genes under any condition of interest.

• Journal of Applied Biological Chemistry
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• v.56 no.2
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• pp.109-112
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• 2013

Azole fungicides are one of the most wide-spread antifungal compounds in agriculture and pharmaceutical applications. Their major mode of action is the inhibition of ergosterol biosynthesis, giving depletion of ergosterol, precursors and abnormal steroids. However, metabolic consequences of such inhibition, other than steroidal metabolitesare not well established. Comprehensive metabolic profiles of Saccharomyces cerevisiae has been presented in this study. Wild type yeast was treated either with glucose as control or azole fungicide (ketoconazole). Both polar metabolites and lipids were analyzed with gas chromatography-mass spectrometry. Approximately over 180 metabolites were characterized, among which 18 of them were accumulated or depleted by fungicide treatment. Steroid profile gives the most prominent differences, including the accumulation of lanosterol and the depletion of zymosterol and ergosterol. However, the polar metabolite profile was also highly different in pesticide treatment. The concentration of proline and its precursors, glutamate and ornithine were markedly reduced by ketoconazole. Lysine and glycine level was also decreased while the concentrations of serine and homoserine were increased. The overall metabolic profile indicates that azole fungicide treatment induces the depletion of many polar metabolites, which are important in stress response.