• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.59-62
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• 2001

The dried fruit-body of Daedaleopsis tricolor was extracted by the petroleum ether. The extracts were purified by liquid-liquid extraction, column chromatography, and recrystallization. The purified compound was a colorless orthorhombic crystal form. Its melting point, molecular weight and molar extinction coefficient $(\varepsilon)$ were estimated $168-170^{\circ}C$, 424 and 3,935 at 208 nm, respectively. Its structure was elucidated to be 20(29)-lupen-3-one by UV-Vis, FT-IR, NMR and X-ray crystallographic analysis. It showed antifungal activities against Saccharomyces cerevisiae and Microsporum gypseum, and antibacterial activities against Escherichia coli, Proteus vulgaris, Pseudomonas pyocyanea, Bacillus subtilis, and Staphylococcus aureus. In addition, this compound showed an antioxidative activity on lipid-peroxidation by 6.4%.

• Mycobiology
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• v.47 no.1
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• pp.87-96
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• 2019

Fungi produce various secondary metabolites that have beneficial and harmful effects on other organisms. Those bioactive metabolites have been explored as potential medicinal and antimicrobial resources. However, the activities of the culture filtrate (CF) and metabolites of whiterot fungus (Schizophyllum commune) have been underexplored. In this study, we assayed the antimicrobial activities of CF obtained from white-rot fungus against various plant pathogens and evaluated its efficacy for controlling anthracnose and gray mold in pepper plants. The CF inhibited the mycelial growth of various fungal plant pathogens, but not of bacterial pathogens. Diluted concentrations of CF significantly suppressed the severity of anthracnose and gray mold in pepper fruits. Furthermore, the incidence of anthracnose in field conditions was reduced by treatment with a 12.5% dilution of CF. The active compound responsible for the antifungal and disease control activity was identified and verified as schizostatin. Our results indicate that the CF of white-rot fungus can be used as an eco-friendly natural product against fungal plant pathogens. Moreover, the compound, schizostatin could be used as a biochemical resource or precursor for development as a pesticide. To the best of our knowledge, this is the first report on the control of plant diseases using CF and active compound from white-rot fungus. We discussed the controversial antagonistic activity of schizostatin and believe that the CF of white-rot fungus or its active compound, schizostatin, could be used as a biochemical pesticide against fungal diseases such as anthracnose and gray mold in many vegetables.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.30-30
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• 2022

Natural products decursin and decursinol angelate were recently reported as benign fungicides for controlling rice blast. Inspired by the structural similarity of the cumarin compounds and gained hint from the skeletal motifs, we designed and prepared synthetic compounds to increase the natural product efficacy and evaluated their antifungal activities against various plant disease pathogens in vitro. Synthetically prepared compound 4 and 5 indeed suppressed the mycelial growth of B. cinerea, F. oxysporum, P. italicum, and R. quercus-mongolicae. Additionally, compound 5 effectively prevents the growth of C. coccodes and C. parasitica. Furthermore, both 4 and 5 possess better inhibitory activities on spore germination of F. oxysporum and M. oryzae than the natural product decursin. These results suggest that the effect of the lead compound for plant disease protection can be improved by tuning the structure of the original natural product and decursinol chloroacrylates 4 and 5 are candidates for the control of F. oxysporum and M. oryzae.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.98-98
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• 2022

Natural products decursin and decursinol angelate were recently reported as benign fungicides for controlling rice blast. Inspired by the structural similarity of the cumarin compounds and gained hint from the skeletal motifs, we designed and prepared synthetic compounds to increase the natural product efficacy and evaluated their antifungal activities against various plant disease pathogens in vitro. Synthetically prepared compound 4 and 5 indeed suppressed the mycelial growth of B. cinerea, F. oxysporum, P. italicum, and R. quercus-mongolicae. Additionally, compound 5 effectively prevents the growth of C. coccodes and C. parasitica. Furthermore, both 4 and 5 possess better inhibitory activities on spore germination of F. oxysporum and M. oryzae than the natural product decursin. These results suggest that the effect of the lead compound for plant disease protection can be improved by tuning the structure of the original natural product and decursinol chloroacrylates 4 and 5 are candidates for the control of F. oxysporum and M. oryzae.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.428-433
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• 1993

A strain that inhibited the growth of Pellicularia sasakii was isolated from the soil and identified as Pseudomonas aeruginosa 3120. A dark brownish antibiotic, MRL3120 isolated and purified from the culture broth of P. aeruginosa 3120 was soluble in ethylacetate, chloroform and methanol, and it was active against gram-positive and negative bacteria as well as fungi. The structure of MRL3120 was identified as a chelate compound consisting of two N-methyl-N-thioformyl-hydroxylamine and a copper ion by the analysis of UV, IR, and EI-MS spectra and other physico-chemical properties and supposed to have a structure of fluopsin C related compound. Addition of $CuSO_4$ into the fermentation medium containing soybean meal increased antifungal activity but no activity was found in the presence of EDTA (0.1%, v/v). However antibiotic MRL3120 was not produced in the fermentation medium containing soytone instead of soybean meal but it was rapidly produced by the addition of $CuSO_4$.

• Archives of Pharmacal Research
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• v.29 no.1
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• pp.16-25
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• 2006

A novel series of 1-(1-benzofuran-2-yl-ethylidene)-4-substituted thiosemicarbazides (2a-d) along with some derived ring systems: substituted-2,3-dihydro-thiazoles(3a-c, 4a-f) and thiazolidin-4-ones(5a-d and 6a-d), were synthesized. In addition, cyanoacetic acid-(1-benzofuran-2-yl-ethylidene) hydrazide(7) was used to prepare another new series of compounds consisting of substituted pyridin-2(1H)-ones(8a-c); 2-thioxo-2,3-dihydro-thiazoles(9a-d) and 2-thioxo-2,3-dihydro-6H-thiazolo[4,5-d]pyrimidin-7-ones (10a-c, 11a-c). The absolute configuration of compound 5c was determined by X-ray crystallography. The compounds prepared were evaluated for their in vitro anti-HIV, anticancer, antibacterial, and antifungal activities. Among the tested compounds, compounds 5c and 9a produced a significant reduction ㅐ ㄹ the viral cytopathic effect (93.19% and 59.55%) at concentrations $>2.0{\times}10^{-4}\;M\;and\;2.5{\times}10^{-5}\;M$respectively. Compound 9a was confirmed to have moderate anti-HIV activity. Compounds 2a, 2d, and 5c showed mild antifungal activity. However, none of the tested compounds showed any significant anticancer activity.

• Research in Plant Disease
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• v.30 no.2
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• pp.189-193
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• 2024

Cucumber (Cucumis sativus L.) is substantial economic importance in South Korea, with its cultivation occupying a significant portion of agricultural land. However, sustainable cucumber production requires effective management of various diseases affecting the crop yield. In this study, we explored the potential of Streptomyces sp. S20-465-derived metabolites in controlling cucumber anthracnose disease caused by Colletotrichum orbiculare. This study identified 4-hydroxy-4-methyl-2-pentanone as a potent antifungal compound present in the n-hexane extract of Streptomyces sp. S20-465 culture filtrate. This compound exhibited significant the disease reduction, demonstrating their potential as control agents. Our findings suggest that Streptomyces sp. S20-465-derived metabolite could serve as an effective tool for managing cucumber anthracnose, offering a sustainable approach to enhancing cucumber production. Further research into the application and efficacy of these compounds in agricultural system will be conducted.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.32-41
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• 2000

Antimicrobial and antioxidative activities on heartwood extractives from Zelkova serrata were investigated to develop a natural fungicide or preservative. The ethanol extract from Z. serrata was fractionated in the order of petroleum ether, diethylether and ethylacetate to determine antimicrobial activity. The highest antimicrobial activity against the tested microorganisms was found in the petroleum ether soluble fraction. An active antimicrobial compound was isolated from petroleum ether soluble fraction, and identified as 7-hydroxy-3-methoxycadalene by $^1H$-, $^{13}C$-NMR and EI-MS spectrometry. This compound showed higher antifungal activity, but lower antibacterial activity than hinokitiol(${\beta}$-thujaplicin), strong antimicrobial compound isolated from Thujopsis dolabrata. Antioxidative activity was also higher than ${\alpha}$-tocopherol and similar to BHT(butylated hydroxytoluene), one of the strongest synthetic antioxidant. As a result, it was concluded that 7-hydroxy-3-methoxycadalene isolated from Z. serrata had strong antifungal and antioxidative activities.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1324-1329
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• 2007

Resveratrol (3,5,4'-trihydroxystilbene) is a naturally occurring, multi-biofunctional chemical existing in grapes and various other plants as a polyphenol type, and it is one of the best known natural anticancer and antiatherosclerosis reagents. In this study, we investigated the antifungal action by resveratrol in Candida albicans, which is a human infectious fungi as an agent of candidiasis. Resveratrol displayed potent fungicidal activity in an energy-dependent manner, without any hemolytic effects against human erythrocytes. It was found that the serum-induced mycelial forms, which playa crucial role in the pathogenesis of C. albicans during host tissue invasion, were disrupted by resveratrol. To understand the correlation between lethal effects and resveratrol action, we examined the physiological changes of C. albicans. A significant accumulation of intracellular trehalose was induced by stress responses to resveratrol action, and a remarkable arrest of cell-cycle processes at the S-phase in C. albicans occured. Therefore, the fungicidal effects of resveratrol demonstrate that this compound is a potential candidate as an antifungal agent in treating infectious diseases by candidal infections.

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.2985-2990
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• 2012

New thiazoline derivatives 7a-c, and thiophenes 9a-c linked to indole moiety were easily prepared via the reaction of the acrylamide derivative 3 with phenacyl bromides 4a-c, depending on the reaction conditions. In addition, the reaction of compound 3 with hydrazonoyl chlorides 11a-f afforded a series of 1,3,4-thiadiazole derivatives 13a-f. Moreover, coupling of 3-(3-methyl-1H-indol-2-yl)-3-oxopropanenitrile (2) with the diazonium salts of 3-phenyl-5-aminopyrazole 16 or 3-amino-1,2,4-triazole 17 gave the corresponding hydrazones 18 and 19, respectively. Cyclization of the latter hydrazones yielded the corresponding pyrazolo[5,1-c]-1,2,4-triazine and 1,2,4-triazolo[5,1-c]-1,2,4-triazine derivatives 20 and 21, respectively. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, $^1H$ NMR and mass spectral data. All the synthesized compounds were tested for in vitro activities against certain strains of fungi such as Aspergillus niger, Aspergillus nodulans, Alternaria alternate. Compounds showed marked inhibition of fungal growth nearly equal to the standards.