• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1031-1036
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• 2005

[ $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ ] (1) was isolated from an ethyl acetate extract of the root bark from Lycium chinense Miller, and its structure was determined using 1D and 2D NMR spectroscopy including DEPT, HMQC, and HMBC. $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ exhibited potent antimicrobial activity against antibiotic-resistant bacterial strains, methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients, and human pathogenic fungi without having any hemolytic effect on human erythrocytes. In particular, compound 1 induced the accumulation of intracellular trehalose on C. albicans as stress response to the drug, and disrupted the dimorphic transition that forms pseudo-hyphae caused by the pathogenesis. This indicates that $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ has excellent potential as a lead compound for the development of antibiotic agents.

• Mycobiology
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• v.30 no.2
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• pp.96-101
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• 2002

Four pathogenic fungal isolates belonging to different genera including Alternaria, Fusarium and Curvularia were isolated from selected diseased weeds growing in the fields in Dakahalia district. The inoculum of these pathogenic fungi specific to weeds were cultured, standardized and formulated as alginate pellets containing mycelium plus culture filtrate. These mycoherbicides were evaluated for disease severity(DS). Maximum DS was obtained with the alginate pellets of mycelium filtrate Fusarium solani. Physiological changes of the treated weed were determined 5 aiid 10 days after treatments. As compared to the healthy weeds, all mycoherbicide formulations significantly decreased the amount of photosynthetic pigments and subsequently soluble and insoluble sugars in the infected weeds. The mycoherbicide formulation of F. solani had the greatest effect on lowering to the abovementioned amount in the leaves of Chenopodium murale. Generally, treatment of weed leaves with the specific mycoherbicide led to a highly significant increase in total phenol content when compared to the healthy control weed. C. murale infected with the mycoherbicide formulation of F. solani had higher levels of phenolic compounds than those other treated weeds particularly after 10 days of inoculation.

• Journal of Life Science
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• v.20 no.2
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• pp.269-274
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• 2010

An antifungal antibiotic-producing strain, BCNU 2003, was isolated from forest soil in Korea. The morphological and physiological characters, and 16S rRNA sequences analysis of strain BCNU 2003 identified this strain as Bacillus genus. The Bacillus sp. BCNU 2003 showed strong antifungal activities against Aspergillus niger, Trichophyton mentagrophytes and Trichophyton rubrum with inhibition ranging from 62.05 to 63.49% by using dual culture technique. Bacillus sp. BCNU 2003 produced a maximum level of antifungal substances under aerobic incubation at 28oC and pH 6.5-7.2 for 6 days in LB broth. Ethyl acetate extract of the cultured broth showed strong antifungal activity and a broad antifungal spectrum against various pathogenic fungi. The minimum inhibitory concentration (MIC) values for its active extracts ranged between 0.0625 mg/ml and 1 mg/ml. In addition, Bacillus sp. BCNU 2003 was determined to have the ability to produce enzymes such as amylase, protease, gelatinase and catalase.

• Korean Journal of Microbiology
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• v.48 no.1
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• pp.16-21
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• 2012

Since many pesticides cause various health and environmental problems, alternative measures to replace them are needed, and the bacteria producing the antifungal substances can be one of them. In this study, several rhizobacteria were isolated and their antifungal activities against some important plant pathogenic fungi were examined. Pseudomonas otitidis TK1 and Paenibacillus peoriae RhAn32 inhibited the growth of Fusarium oxysporum f. sp. niveum and F. oxysporum f. sp. lycopersici by 49.8% and 45.6%, and 45.1% and 48.3%, respectively compared to those of the control. P. peoriae RhAn32 also decreased the growth of F. oxysporum f. sp. raphani by 37.5%. This growth inhibition might be due to the production of antifungal substances, such as siderophore, hydrogen cyanide and chitinase, which were produced by these rhizobacteria. P. otitidis TK1 also produced plant growth hormones indole acetic acid and indole butyric acid at $293.41{\mu}g/mg$ protein and $418.53{\mu}g/mg$ protein, respectively. When P. otitidis TK1 and B. cereus TK2 were inoculated together with F. oxysporum f. sp. lycopersici to the 4 weeks grown tomato seedlings and incubated additional 8 weeks, the stem lengths of tomato increased up to 45.7% and 55.3% and root lengths were raised to 64.9% and 60.8%, respectively than those of the control group. The wet weights increased by 118% and 182%, respectively compared to the control group.

• Korean Journal of Environmental Agriculture
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• v.21 no.3
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• pp.216-222
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• 2002

In order to evaluate the antifungal activity of bacteria against plant pathogenic fungi, 8 bacteria were isolated from mushroom compost hot spring, seaweed, and forest soil and mutants from them were induced by $LD_{95}$ gamma radiation($^{60}Co$). Bacillus circulans K1, Burkholderia gladioli K4 and Bacillus subtilis YS1 showed wide antifungal spectrum against 12 kinds of plant pathogenic fungi. From the radiation sensitivity test, B. gladioli K4 was very sensitive to gamma radiation and its $D_{10}$ value was 0.11 kGy. Antifungal activities of B. circulans Kl-1004 and B. subtilis YS1-1009, which were induced by the radiation of $^{60}Co$ increased against Botryosphaeria dothidea. The mutant strains, B. subtilis YS1-1006 and B. subtilis YS1-1009 were resistant to tebuconazole and copper hydroxide. SAR535, SAR5108, and SAR5118 mutated from Streptomyces sp. SAR01 were antifungal activity deficient mutants against 5 kinds of plant pathogenic fungi compared to wild strain, so that they could be supposed to be model strains far studying antifungal mechanism. It is suggested that various functional types of mutants could be induced by gamma radiation and applied usefully.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.333-341
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• 2021

In this study, to select strains suitable as microbial agent from among rhizosphere microorganisms present in rhizosphere soil and roots, the mineral solubilization ability, antifungal activity against 10 types of plant pathogenic fungi, and plant growth-promoting activity of rhizosphere microorganisms were evaluated. As a result, DDP346 was selected because it has solubilization ability of phosphoric acid, calcium carbonate, silicon, and zinc; nitrogen fixing ability; production ability of siderophore, indole-3-acetic acid, and aminocyclopropane-1-carboxylate deaminase; and antifungal activity against seven types of plant pathogenic fungi. DDP346 showed a 99.9% homology with Acinetobacter pittii DSM 21653 (NR_117621.1); phylogenetic analysis also revealed a close relationship with Acinetobacter pittii based on the 16S rRNA base sequence. The growth conditions of DDP346 were identified as temperatures in the range of 10-40 ℃, pH in the range of 5-11, and salt concentrations in the range of 0-5%. In addition, a negative correlation coefficient (r² = -0.913, p <0.01) was shown between pH change and the solubilized phosphoric acid content of Acinetobacter sp. DDP346, and this is assumed to be due to the organic acid generated during culture. Consequently, through the evaluation of its mineral solubilization ability, antifungal activity against plant pathogenic fungi, and plant growth-promoting activity, the potential for the utilization of Acinetobacter sp. DDP346 as a multi-purpose microbial agent is presented.

• Journal of Dairy Science and Biotechnology
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• v.37 no.3
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• pp.187-195
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• 2019

Seeds and leaves of Raphanus raphanistrum subsp. sativus (radish) are known to contain "raphanin," which has the potential to inhibit pathogenesis associated with foodborne pathogenic bacteria and fungi. In this study, ethanol extracts from R. raphanistrum subsp. sativus (radish) powder was evaluated for antimicrobial action against 6 different foodborne pathogenic bacteria. The current study demonstrated the potential of R. raphanistrum subsp. sativus (radish) in inhibiting the growth of Salmonella enteritidis 110, Cronobacter sakazakii KCTC 2949, Bacillus cereus ATCC 10876, and Staphylococcus aureus ATCC 6538. However, these antimicrobial action were not observed against Listeria monocytogenes ATCC 51776 and Escherichia coli 23716. Hence, this study indicates that R. raphanistrum subsp. sativus (radish) could be used as a natural biopreservative with antimicrobial effects for improving food safety, and as a functional food in the commercial food industry.

• The Korean Journal of Mycology
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• v.31 no.2
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• pp.67-76
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• 2003

This study was performed to screen antimicrobial activities of 198 extracts from 66 Korean mushrooms against 19 human pathogenic microorganisms using paper disc method. Mushrooms were extracted with petroleum ether 80% ethanol and distilled water in that order Among the extracts with antimicrobial activities, 1 water extract of Amanita virgineoides, 8 ethanolic extracts including Amanita and 1 petroleum ether extrac of Psathyrella hydrophila were highly active against fungi, respectively. In addition to, 24 extracts including Amanita pseudoporphyria, Amanita spissacea, 3 extaracts including Paxillus curtisii were highly active against Gram negative and positive bacteria, respectively.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.432-436
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• 2014

The soil-borne ascomycete fungus Cylindrocarpon destructans causes ginseng root rot disease and produces various secondary metabolites such as brefeldin A and radicicol. The slow growth of this fungus compared with other plant pathogenic and saprophytic fungi in soil disturbs isolation of this fungus from soil and infected ginseng. In this study, we developed a selective medium for C. destructans using radicicol produced by this fungus. Supplementing 50 mg/L of radicicol to medium inhibited the mycelia growth of other fungi including Botrytis cinerea, Rhizoctonia solani and Alternaria panax, but did not affect the growth of C. destructans. In addition, conidia germination of other fungal species except for C. destructans was inhibited in submerged culture supplemented with radicicol. This medium provides a very efficient tool for isolating C. destructans and also can be used as an enrichment medium for this fungus.

• Korean Journal Plant Pathology
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• v.13 no.1
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• pp.18-21
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• 1997

Bipolaris panici-miliacei, Cercospora fusimaculans, Fusarium moniliforme and Rhizoctonia solani were pathogenic fungi detected from 5 seed samples of common millet (Panicum miliaceum). Morphological characters of B. panici-miliacei were as follows. Conidiophores were dark olivaceous brown, simple, cylindrical, geniculate, and septate. Conidia were fusoid, dark olivaceous brown, tapering gradually toward the ends, straight to slightly curved, 3~13 distoseptate, and 29.4~155.4$\times$10~26 ${\mu}{\textrm}{m}$ in size with dark hilum included within the contour of the basal cell. Seed infection with B. panici-miliacei caused seed rotting, coleoptile spot, and seedling blight of common millet plants. According to the inoculation experiments, B. panici-miliacei showed strong virulence on the young seedlings of common millet, but very weak virulence on the young seedlings of rice (Oryza sativa) and foxtail millet (Setaria italica).