• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.313-319
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• 2007

Nine plant growth regulators (PGRs) were tested for in vivo antifungal activities against on rice blast. They showed higher in vivo antifungal activities when they were applied on rice plants by soil drench rather than foliar spray. Except for 2,4-D at $500\;{\mu}g\;mL^{-1}$, the others showed a very low or no activity against the disease in foliar spray applications. In contrast, 2,4-D, indole butyric acid (IBA) and triiodobenzoic acid, at $500\;{\mu}g\;mL^{-1}$, showed control values of 98.9, 97.8 and 88.9% in soil drench applications. Furthermore, the control activity of IBA was dependent on its concentration against rice blast; IBA suppressed the development of rice blast by 71.7% at $125\;{\mu}g\;mL^{-1}$ and 85.8% at $250\;{\mu}g\;mL^{-1}$. IBA also controlled the development of rice blast on adult plants by 63.9% at a dosage of 2.56 kg/10a. The results revealed that IBA has a good activity against rice blast when it is applied by soil drench.

• The Korean Journal of Pharmacology
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• v.9 no.2
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• pp.1-6
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• 1973

Although numerous drugs are available for the treatment of superficial fungi infections of skin, the clinical effects of the majority of such drugs are not satisfactory. In the hope of searching the effective drugs for superficial fungi infections, authors studied whether Veratrum rhizoma extracts had any effect on fungi, with water extract (VRWE), ethanol extract (VREE) and methanol extract (VRME) from Veratrum album L. var. grandiflorum Max. In in vitro studies, the spores of fungi were inoculated on Sabouraud's glucose agar media which contained three extracts of Veratrun rhizoma in each concentration of $500\;{\mu}g/ml$, $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$ respectively, and the growth of the fungi were observed for 3 weeks. The species of the fungi used in these experiments were Epidermophyton floccosum, Microsporum canis, Microsporum nanum, Microsporum gypseum, Microsporum cookei, Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans and Trichophyton verrucosum. The results of the studies were as follows: 1. The growth of M. canis, M. nanum, T mentagrophytes and T. tonsurans were slightly inhibited by VRWE $1,000\;{\mu}g/ml$, and with VRWE $5,000\;{\mu}g/ml$, the growth of E. floccosum, M. gypseum and T. rubrum were slightly inhibited, moderate inhibition on the growth of M. canis, M. nanum, M. cookei, T. mentagrophytes and T. tonsurans were showed by VRWE $5,000\;{\mu}g/ml$. 2. With $500\;{\mu}g/ml$ of VREE, the inhibition on growth of E. floccosum, M. nanum and M. gypseum were slight, however significant inhibition on the growth of M. canis, M. cookei, T. mentagrophytes, T. rubrum and T. tonsurans were observed. The growth of M. nanum and M. gypseum were moderately inhibited, and significant inhibition on the growth of E. floccosum, M. canis, M. cookei, T. mentagrophytes, T. rubrum and T. tonsurans were observed by VREE $1,000\;{\mu}g/ml$. By VREE $5,000\;{\mu}g/ml$, the growth of all tested fungi were significantly inhibited except T. verrucosuia being showed slight inhibition. 3. Significant inhibition on the growth of M. canis, T, mentagrophytes, T. rubrum and T. tonsurans were noted, and moderate inhibition of M. nanum, slight inhibition of E. floccosum and M. gypseum in growth were observed by VRME $500\;{\mu}g/ml$. The growth of E. floccosum, M. canis, M. nanum, M. cookei, T. mentsgrophytes, T. rubrum and T. tonsurans were significantly inhibited by VRME $1,000\;{\mu}g/ml$, and that of M. gypseum was moderate. With $5,000\;{\mu}g/ml$ of VRME, significant inhibition on the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T mentagrophytes, T. rubrum and T. tonsurans were observed, and T. verrucosum was showed only slight inhibition. From the above results, it was found that the extracts of organic solvents from Veratrum rhizoma (VREE & VRME) exerted significant antifungal activity, and their effects were probably derived from the pharmacological action of steroidal alkaloids.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.315-321
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• 2010

Malassezia furfur is an important causal factor for seborrheic dermatitis. Nowadays, the drugs available to treat this fungal infection are few. Several studies have documented the biological activity of essential oils. However, its antifungal properties are not completely understood, especially its anti-Malassezia activity. The aim of this study were to evaluate the effect of the plant essential oils on the growth of M. furfur using disk diffusion method and analyze by Gas chromatography-mass spectrometry (GC-MS) most active essential oils. In first screening, the 17 plant essential oils have possesses inhibitory activity against M. furfur at 2 mg/mL. Among the plant essential oils, oil of Citrus auranifoli was most active against M. furfur and its activity showed dose dependency. This anti-malassezial activity was high than that of itraconazole at 2 mg/mL. Oil of Citrus auranifolia also was phytochemically examined by GC-MS analysis, its main constituents were identified as limonene, ${\gamma}$-terpinene and terpinolene. It can be concluded that essential oils of Citrus auranifolia may have interesting applications to control fungal-derived diseases.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.465-472
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• 2019

Candida albicans is an opportunistic human pathogen that causes infections. Candidiasis is often related to antifungal resistance because the pathogen has the ability to form biofilms. In a previous study, we found that the Salvia miltiorriza ethanol extract demonstrated anticandidal activity by altering membrane permeability and inhibiting the cell wall synthesis in C. albicans. Our results here demonstrate that $78{\mu}g/ml$ of the S. miltiorriza extract significantly diminished the early stage biofilms formed by 10 clinical C. albicans isolates by 51.3%; this was analyzed by 2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide salt (XTT) reduction assay. The effect of the S. miltiorrhiza extract on the adhesion of C. albicans cells to polystyrene plates and germ tube formation was examined via microscopic investigation. Although the density of the adhered cells was remarkably reduced up on incubation with $39{\mu}g/ml$ S. miltiorrhiza extract, germ tube formation by C. albicans was rarely affected. Quantitative real-time PCR analysis showed that the S. miltiorrhiza extract downregulated the expression of C. albicans hypha-specific genes, EAP1 by 34.7% (p < 0.001), ALS1 by 45.0% (p < 0.001), ALS3 by 48.1% (p < 0.001), and ECE1 by 21.3% (p = 0.006), respectively. Our data suggest that the S. miltiorrhiza ethanol extract significantly inhibited the early stage of biofilm formation by C. albicans by interfering with cell adhesion, by downregulating EAP1, ALS1 and ALS3, and presumably by modifying the cell wall and membrane structure.

• Journal of Life Science
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• v.18 no.6
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• pp.858-864
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• 2008

In the greenhouse fields for fruits and vegetables during the winter in Korea, there are serious damages by the sclerotium diseases due to the low temperature and humidity. This study was carried out to select an antagonic agent for the biological control of the sclerotium diseases. The 55 antagonic agents were selected from the rhizosphere in soil where the fruits and vegetables were cultivated in the green house fields, and strain AB02 among the tested isolates was estimated to be the strongest antagonist against the sclerotium disease. Using strain AB02, the antifungal spectrum was tested against 5 different plant pathogens. According to the results of the test, strain AB02 . showed the high antagonistic effect against Botrytis cinerea and Sclerotinia sclerotiorum. For the experiment of biological control against the sclerotium disease, it was estimated the suppression effect and the control effect by the strain in the pot experiment using the green perilla. According to the result of the pot experiments, the suppression effect was 40% and the control effect was 62%, respectively. For the stimulation effect of the tested plant growth by strain AB02 compared to the control, it was improved as 120% for the total length, 141% for the liveweight, 121% for the total number of leaves, 185% for the leaf area, and 327% for the liveweight of the root, respectively. Strain AB02 showing the antagonistic effect against the sclerotium disease and the stimulation effect for the plant growth was identified as Bacillus sp.

• Advances in Traditional Medicine
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• v.5 no.4
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• pp.308-315
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• 2005

Aflatoxin contamination is a major problem in several food crops. Aflatoxin, a mycotoxin, produced by Aspergillus flavus has gained immense concern in the scientific world because of its tremendous harmful effects. The study was focused to see the effect of oil and aqueous extract of neem (Azadirachta indica) seeds on the growth of Aspergillus and production of aflatoxin by the mold. Various amounts of neem oil $(5\;-\;50\;{\mu}l/ml)$ and aqueous extract of neem (5 - 50 mg/ml) were used both in the broth as well as the solid medium. Fungistatic (MIC) and minimal fungicidal concentrations (MFC) were found to be $10\;{\mu}l/ml$ and $50\;{\mu}l/ml$ respectively for neem seed oil. At the concentration of $5\;{\mu}l/ml$ neem oil and 5 mg/ml of aqueous extract, a significant decrease in the aflatoxin content was found in broth medium. Aflatoxin production was totally inhibited at $50\;{\mu}l/ml$ and 50 mg/ml for neem oil and aqueous extract of neem respectively, in both treatments. There was significant inhibition of mycelium dry weight by the neem seed oil. Mycelial growth was totally inhibited at $20\;{\mu}l/ml$ of neem seed oil concentration in broth, whereas it was not affected at all by aqueous extract. It can therefore be inferred that the oil and extract from the neem seed leads to inhibition of aflatoxin production while neem seed oil also significantly inhibits the mycelial growth. Neem seed oil thus can be used as potent, natural and easily available anti-aflatoxigenic agent.

• Natural Product Sciences
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• v.23 no.2
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• pp.125-131
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• 2017

Clitoria ternatea or Commonly known blue pea, is a perennial climber crop native to Asian countries. The current study was aimed to evaluate the antimicrobial activity C. ternatea extract on food borne microorganisms and its antifungal effect on Penicillium expansum. The extract showed significant antimicrobial activity against 3 Gram positive bacteria, 2 Gram negative bacteria and 1 filamentous fungus on disc diffusion assay. The extract also showed good biocidal effect on all Gram positive bacteria tested and P. expansum. However, the kill curve analysis revealed that the fungicidal activity of the extract against P. expansum conidia was depend on the concentration of the extract and the time of exposure of the conidia to the extract. The scanning electron micrograph of the extract treated P. expansum culture showed alterations in the morphology of fungal hyphae. The germination of P. expansum conidia was completely inhibited and conidial development was totally suppressed by the extract, suggesting the possible mode of action of anthocyanin. Besides, the extract also exhibited 5.0-log suppression of microbial growth relative to control in the rice model. The results indicate the potential use of the C. ternatea anthocyanin as food biopreservative.

• Microbiology and Biotechnology Letters
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• v.39 no.4
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• pp.387-389
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• 2011

A previous study of ours indicated that Citrus auranifoli oil possesses antifungal activity against Malassezia furfur and Malassezia pachydermatis. In this study, we evaluated the anti-M. furfur and M. pachydermatis activities of limonene, which is a major component of C. aurantifolia oil, using the disk diffusion method. We also examined cytotoxicity against human normal epithelial (Beas-2B) cells using the cytopathic effect reduction (CPE) method. The results revealed that the minimum fungicidal concentration (MFC) value of limonene is lower than the value for itraconazole. The MFC value of limonene was seen to be 7.81 ${\mu}g$/mL against M. furfur and 3.90 ${\mu}g$/mL against M. pachydermatis. MFC values of itraconazole against M. furfur and M. pachydermatis were 62.50 ${\mu}g$/mL and 31.25 ${\mu}g$/mL, respectively. In addition, it was noted that limonene was not toxic to Beas-2B cells with normal morphology at a concentration of 100 ${\mu}g$/mL. However, itraconazole exhibited weak toxicity at the same concentration. Therefore, our results indicate that limonene could potentially be effective at controlling M. furfur and M. pachydermatis infections with no cytotoxicity.

• Journal of Life Science
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• v.13 no.5
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• pp.582-589
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• 2003

The effect of useful rhizobacterium added in bed soil on the early growth promotion of red pepper plug seedlings was investigated. Total 540 colonies of rhizobacteria from 385 samples of eggplant family roots were isolated. Among these, 5 isolates were selected for antifungal activity against pathogenic fungi such as Alternaria solani, Botrytis cinerea, Fusarium oxysporium, Phytophthora capsici, and Sclerotia sclerotiorum. Of all the isolates, MJ-3 having the most pronounced growth-promoting ability for red pepper was finally selected and identified as Bacillus amyloliquefaciens through characterization of biochemical and bacteriological aspects and 16S rDNA sequence. The plant height, stem diameter, root length and fresh weight of red pepper plants which were grown with inoculation of B. amyloliquefaciens MJ-3 were higher than those without inoculation. Especially the root weight of the inoculated red pepper plant increased by 44.3%, the content of endogenous plant hormone (CA$_1$) being 0.556 ng/g (dry weight).

• KSBB Journal
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• v.23 no.2
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• pp.125-130
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• 2008

We investigated the biological activities of ethanol extract from the seawater algae, Chlorella elliposidea C020 such as antibacterial activity, anti-oxidant activity, tyrosinase inhibitory activity and hemolytic activity against human erythrocytes. Extract was obtained from various solvent, methanol, ethanol, acetone and ethanol + acetone (1:1, v/v%), 95% ethanol proved to be best extraction solvents. The contents of ethanol extract were higher in freeze-dried sample than that in frozen-thawing. Antibacterial activities of ethanol extract showed strong inhibitory effect against Bacillus subtilis PM125, Bacillus licheniformis and fish pathogenic bacteria, Vibrio parahaemolyticus KCTC2471 and Edward tarda NUF251. However, this extract didn't worked against antifungal activity against Candida albicans KCTC1940. And, ethanol extract was without hemolytic activity against human erythorocytes. The ethanol extract showed 75% of free radical scavanging effect on 2.0 mg/mL using DPPH method. In tyrosinase inhibition assay of ethanol extract, $IC_{50}$ (Inhibition Concentration) was measured as 10.87 mg/mL. Conclusionally, ethanol extract of Chlorella elliposidea C020 has good candidate for bioactive materials.