• Research in Plant Disease
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• v.18 no.1
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• pp.10-16
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• 2012

This study was conducted to examine the effects of the seeding rate on the disease incidence of sharp eyespot(Rhizoctonia cerealis) on three different varieties and to select effective chemicals to control the disease. When the seeds were sown twice as many as the recommendation, the disease incidence increased by approximately 13%. However, the susceptible variety 'Jopummil' alone showed the significantly enhanced disease incidence at a two-fold seeding rate. Two chemicals such as Hexaconazole EC and Tebuconazole EC highly inhibited the fungal growth on agar medium. However, two strobilurin fungicides such as Pyraclostrobin EC and Trifloxystrobin SC were relatively weak. The fungicides tested displayed the similar in vivo antifungal activities as in vitro activities. Hexaconazole EC and Tebuconazole EC showed the strongest both protective and curative activities and the protective activities of the chemicals were generally higher than the curative activities. Hexaconazole EC and Tebuconazole EC controlled the disease by 64% and 73%, respectively, and the two chemicals reduced the disease by 45% and 39%, respectively, when they were applied one day after pathogen inoculation. These results indicate that both Hexaconazole EC and Tebuconazole EC could be used to control sharp eyespot on wheat.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.3
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• pp.175-180
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• 2019

Torilis Japonica (TJ) has been used as an anti-allergy, antifungal, and antibacterial agent. Recent studies have reported that it also shows anti-cancer effects. It is report that TJ inhibits melanin synthesis in melanocyte in the skin. However, the effect and mechanism of TJ extract (TJE) on Ultraviolet (UV)B-induced photoaging are unknown. In this study, we investigated the preventive effects of TJE on matrix metalloproteinase (MMP)-1 and MMP-3 expressions and the underlying molecular mechanism in UVB-irradiated primary human dermal fibroblasts (HDFs). The effect of TJE on HDF cell viability was determined using the XTT assay and cell counting. MMP-1 and MMP-3 expressions levels were measured by western blotting and real-time PCR analysis. Activations of mitogen-activated protein kinase (MAPKinase), nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$), and activator protein-1(AP-1) were measured by western blotting. Our results showed that TJE effectively reduced UVB-induced MMP-1 and MMP-3 protein and mRNA levels. Moreover, TJE significantly blocked the UVB-induced activation of MAPK (p38 and JNK) and transcription factors ($NF-{\kappa}B$ and AP-1), but not ERK. Taken together, our results suggest that the TJE inhibits UVB-induced MMP expressions in HDFs and its may be a potential agent for the prevention and treatment of skin photoaging.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.561-574
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• 2021

This study was conducted to evaluate the control efficacy of the organic farming materials (OFMs) on tuber rot of Gastrodia elata caused by Fusarium spp. The antifungal activities in vitro as well as the suppressive effect of 15 OFMs on the spore germination and germ tube growth by inoculating spore suspension on immature tubers in vivo were investigated. 7 OFMs inhibited the mycelial growth of Fusarium spp. and 7 of them were microbial agents. In the screening using immature tubers, 3 OFMs were very effective with control efficacy value of 70%. Among them, sulfur provided suppressive effect on both mycelial growth and spore germination against tuber rot of G. elata. Finally, 3 OFMs were selected to test the protective and curative effects, and all chosen OFMs significantly suppressed disease incidence when applied in the preventive action, in comparison with the curative action. Especially, sulfur and Bacillus subtilis gave excellent protective control efficacy with control values of 93.2% and 86.9%, respectively, whereas its curative control effect was relatively low (73.3%, 60.2%). On the other hand, the preventive and curative effects of citronella + paraffin oil + ethyl alcohol were 73.3% and 67.0%, respectively. This study suggests that tuber rot of G. elata can be controlled by some OFMs in the rain shelter greenhouse under continuous cultivation condition and protective treatment is more important and efficient.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.116-122
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• 2017

Basic dyes such as malachite green and methylene blue have been used as disinfectants to control water fungal infections since the 1930s. However, after succeeding reports of carcinogenicity and bioaccumulation of the dye, their use was forbidden in lieu of public health. This study undertook to evaluate the therapeutic effect of sulfur solution processed by effective microorganisms (EM-PSS) against Saprolegnia parasitica infection, and its safety in fish. In vitro antifungal evaluation of EM-PSS inhibited the growth of S. parasitica mycelia at concentrations of 50 ppm or higher. The acute toxicity test of EM-PSS to the mud fish (Misgurnus mizolepis) measured a no effect concentration (NOEC) at 100 ppm, the lowest effect concentration (LOEC) at 125 ppm, and the half-lethal concentration ($LC_{50}$) at 125 ppm in juvenile and 250 ppm in the immature stage. In addition, the ecotoxicity test of EM-PSS using Daphnia magna inhibited swimming of D. magna at concentrations of 100 ppm or less. Lastly, the EM-PSS prevented infection of S. parasitica to mud fish, at concentrations of 50 ppm. Furthermore, at 100 ppm concentration, the EM-PSS showed no acute toxicity on mud fish, nor any eco-toxic effects on D. magnano. Therefore, we conclude that carcinogenic disinfectants such as malachite green and methylene blue could be replaced by EM-PSS to remove S. parasitica in mud fish farming, and might be a potential eco-friendly disinfectant in aquaculture.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.383-395
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• 2014

When we investigated seed infestation by fungal pathogens from 51 varieties in 9 crops, the contamination rate of rice and sesame seeds was high. Therefore, to control seed-borne diseases, we obtained extracts from commercial products of Kimchi, Gochujang, Doenjang, Ganjang, Makgeolli and Tohajut and their suppressive effects against seed-borne diseases were studied. In addition, bacterial strains were screened to control rice seed-borne diseases in vitro and in vivo. Among forty food extracts, eleven food-extracts suppressed incidence of seedling rots in vitro and five food extracts increased 8-33% of healthy seedling in the greenhouse. Among 218 isolates from 40 fermented foods, 43 isolates showed high antifungal activity against seven fungal pathogens. When we tested 43 isolates for the reduction of rice seed borne disease, 32 isolates were able to reduce the rice seed borne disease. Among 32 isolates, 17 isolates reduced significantly seedling rot and increased healthy seedlings, the other isolates except for Kc4-2 and Mkl 2-2 increased shoot emergence and the percentage of healthy plants. Thirty isolates with high antifungal activity and suppressive effect against rice seedling rots were identified by 16S rRNA sequencing. Twenty one of thirty isolates were identified as Bacillus spp. Three isolates from Makgeolli were identified as Saccharomyces cerevisiae. B. amyloliquifaciens were isolated from six Korean traditional fermented foods except for Ganjang. B. amyloliquifaciens were majority in the effective bacterial population of Gochujang and Jutgal. Relatively diverse Bacillus species including B. subtilis, B. pumilus, and B. amyloliquificiens were isolated from Kimchi. The selected effective microorganisms from Korean fermented foods founded to be effective for controlling seed-borne diseases of rice in vitro and in the greenhouse. We think that Korean fermented foods and their useful microorganisms can be used as biocontrol agents for suppressing rice seed-borne diseases based on above described results.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.447-453
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• 2007

With a broad objective for the development of microbial based fertilizers, a total of 373 strains were isolated from rhizoplane and rhizosphere of pepper, tomato, lettuce, pasture, and grass. The efficacy of the isolates to augument overall plant growth was evaluated. After screening for their plant growth promotion and antagonistic properties in vitro efficient strains were further selected. The most efficient strains was characterized by 16S rRNA gene sequences and biochemical techniques and was designated as Bacillus subtilis S37-2. The strains facilitated plant growth and inhibited the plant phathogenic fungi such as Fusarium oxysporum (KACC 40037, Rhizoctonia solani (KACC 40140), and Sclerotinia sclerotiorum (KACC 40457). Pot based bioassay using lettuce as test plant was conducted by inoculating suspension ($10^5$ to $10^8cells\;mL^{-1}$) of B. subtilis S37-2 to the rhizosphere of lettuce cultivated in soil pots. Compared with non-inoculated pots, marked increase in leaf (42.3%) and root mass (48.7%) was observed in the inoculation group where the 50ml of cell mixture ($8.7{\times}10^8cells\;ml^{-1}$) was applied to the rhizosphere of letuce either once or twice. Antagonistic effects of B. subtilis S37-2 strain on S. sclerotiorum (KACC 40457) were tested. All the tested lettuce plants perished after 9 days in treatment containing only S. sclerotiorum, but only 17% of lettuce was perished in the inoculation plot. B. subtilis grew well in the TSB culture medium. The isolates grew better in yeast extracts than peptone and tryptone as nitrogen source. The growth rate was 2~4 times greater at $37^{\circ}C$ as compared with $30^{\circ}C$ incubation temperature. B. subitlis S37-2 produced $0.1{\mu}g\;ml^{-1}$ of IAA (indole 3-acetic acid) in the TSB medium containing L-tryptophan($20mg\;L^{-1}$) in 24 hours.

• Research in Plant Disease
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• v.29 no.3
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• pp.268-275
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• 2023

This study was conducted to confirm the utilization of Pleurospermum camtschaticum root extract as an organic agricultural material. Antioxidant activity of P. camtschaticum root extract, closely related to antibacterial activity, increased in a dose-dependent manner. In mycelial growth inhibitory activity, 100% P. camtschaticum root extract supressed over 70% for Colletotrichum coccodes and over 68% for Colletotrichum dematium. In the pepper fruit anthracnose development test, the size of the lesion decreased in a dose-dependent manner, which showed the same tendency as the previous results in inhibitory activity on mycelial growth. In the pepper seed germination and red pepper growth promotion test of P. camtschaticum root extract, oposite results was confirmed. The lower the concentration, the more the seed germination and growth promotion effects were shown. The phenol content of pepper leaves was also measured after pepper growth promotion test have been completed. The phenol content related to antibacterial activity increased in all treated groups compared to the untreated group. Therefore, the results of this study showed the possibility of development as an organic material.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.401-406
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• 1992

Antifungal substances against three plant pathogenic fungi, Phytophthora capsici, Phytophthora nicotianae var. parasitica and Rhizoctionaia solani were fractionated cultures of Streptomyces sp. A-2 strain isolated in Korean soils. Characterizations of active substances related with antagonistic effects were follows : 1. The excellent media which showed the transfer efficiency of antagonistic substances from Streptomyces sp. A-2 strain G.Y.B and B.H.I. among four that are glucose yeast broth (G.Y.B), $M\ddot{u}eller$, brain heart infusion(B.H.I.) and Czapek media. Active substances which were transfered into ethylacetate or left in residual aqueous phase did not lose antagonistic activity in spite of autoclavation. This indicated that bonds of these compounds were rigid enough to keep activity under such conditions. 2. Antagonistic substances were extracted according to adjustment of pH 3 or pH12 to 5 day-old B.H.I. broth cultures of Streptomyces sp. A-2 strain. Comparative analysis fluorescent bands on HPTLC to antagonsitic spectra against three phytopathogenic fungi indicated that major substances with antagonistic activity were extracted regardless of different pH adjustment to broth cultures. Since UV spectrum of these fractions scanned from 500nm to 200nm was similiar to that of polyene macrolide, major substances related with antagonistic activities were assumed to be polyene derivatives antibiotics.

• Research in Plant Disease
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• v.20 no.4
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• pp.259-263
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• 2014

For application of sodium hypochlorite as a seed disinfectant to the control of bakanae disease caused by Gibberella fujikuroi in rice, we investigated the effects of sodium hypochlorite for antifungal activity, eliminating fungus from seeds and reducing disease occurrence in vitro and greenhouse. The viability of the pathogen was significantly reduced at $80{\mu}l/l$ concentration of sodium hypochlorite, and the pathogens did not grow at over $100{\mu}l/l$ concentration of sodium hypochlorite. The effect of eliminating fungus was 90% at treatment of 0.3% sodium hypochlorite solution to infected rice seeds for eight hours. When the rice seeds were soaked into 0.5% and 0.3% sodium hypochlorite solutions for twelve hours, the disease incidences of rice seedling were remarkably reduced to 4.3% and 4.7%, respectively, compared to 97.3% of non-treatment control. The rates of seedling stand were 29.1% and 26.9% higher with the sodium hypochlorite treatment than that of non-treatment control. When prochloraz and sodium hypochlorite was treated to naturally severely infested rice seeds with bakanae disease, the disinfection effect was higher than that of prochloraz alone treatment. When the seeds were soaked in sodium hypochlorite before or after prochloraz, the rate of seed contamination was low as 4.0% or 6.3%, respectively, compared to prochloraz alone as 13.7%. The disease incidence was low as 3.7% or 8.3%, respectively, compared to prochloraz alone as 14.3%. The disinfection effect of treatment with prochloraz after sodium hypochlorite was higher than that of treatment with prochloraz before sodium hypochlorite.

• Journal of Pharmaceutical Investigation
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• v.33 no.2
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• pp.135-140
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• 2003

Fluconazole is an orally active bis-triazole antifungal agent, which is used in the treatment of superficial and systemic candidiasis and in the treatment of cryptococcal infections in patients with the acquired immuno deficiency syndrome (AIDS). The purpose of the present study was to evaluate the bioequivalence of two fluconazole capsules, Diflucan (Pfizer Pharmaceuticals Korea Inc.) and Flucona (Korean Drug Pharmaceuticals Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The fluconazole release from the two fluconazole capsules in vitro was tested using KP VII Apparatus II method at 0.1 M hydrochloride dissolution media. Twenty normal male volunteers, $23.60{\pm}1.88$ years in age and $63.57{\pm}6.17\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After three capsules containing 50 mg as fluconazole was orally administered, blood was taken at predetermined time intervals and the concentrations of fluconazole in serum were determined using HPLC method with UV detector. The dissolution profiles of two fluconazole capsules were very similar at 0.1 M hydrochloride dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t,\;C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$ and $C_{max}$ and untransformed $T_{max}$. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between two capsules based on the Diflucan were 4.96%, 5.65% and -13.76%, respectively. There were no sequence effects between two capsules in these parameter. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) $(e.g.,\;log(1.01){\sim}log(1.08)\;and\;log(1.00){\sim}log(1.12)\;for\;AUC_t\;and\;C_{max},\;respectively)$, indicating that Flucona capsule is bioequivalent to Diflucan capsule.