• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.305-310
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• 2023

This study aimed to determine the human androgen receptor (AR)-mediated endocrine disrupting potential of parabens and triclosan in food and household products using a cell-based assay in the OECD TG No.458, the 22Rv1/MMTV_GR-KO transcriptional activation assay. Four parabens (methyl-, ethyl-, propyl-, and butyl-) are determined as AR antagonists in OECD TG No.458. However, their AR antagonistic effects were not exhibited in the presence of the S9 hepatic fraction. Triclosan is also classified as an AR antagonist, and the AR antagonistic effect induced by triclosan significantly decreased in the presence of the phase I + II S9 fraction. Regarding the mechanism of AR antagonism induced by parabens and triclosan, the AR-mediated endocrine disrupting effects were exhibited through suppressing the translocation of ligand-bound AR to the nucleus via blocking of AR dimerization in the cytosol. These results indicate that the four parabens and triclosan have AR-mediated endocrine disrupting potential through an AR antagonistic effect via inhibiting AR dimerization; however, their endocrine disrupting effects deceased in the presence of hepatic metabolic enzymes.

• Asian Journal of Turfgrass Science
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• v.13 no.1
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• pp.55-66
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• 1999

Effect of an antagonistic bacterium AF-2001, Pseudomonas cepacia, on control of turfgrass diseases as brown patch, Pythium blight, dollar spot, and large patch were evaluated in vitro and in vivo. Results obtained in this study are summarized as follows. 1. Pseudomonas cepacia AF-2001 showed antagonism against to the pathogens causing brown patch, Pythium blighe, dollar spot and large patch. Especially, the biological agent showed strong antagonistic effect on the causal pathogens of brown patch, dollar spot, and anthracnose, but weak on Pythium blight 2. Populotion density of P. cepacia AR-2001 decreased ra;idly in turfgrass soils. Initial population of the agent was 2.4$\times$107 cfu/g soil, however, decreased to 1.4$\times$103, 6$\times$102 and 0 cfu/g soil on 10, 20, and 30 days after application, respectively. 3. Under the controlled controlled conditions of $27^{\circ}C$ and 95% RH, P. cepacia AR-2001 showed 100% control efficacy on brown patch either by pre-treatment or post-treatment of infection. However, Pythium blight was controlled about 94% by pre-treatment and only 29% by post-treatment 4. In field trials, P. cepacia AF-2001 did not suppress large patch and the control efficacy on other turfgrass diseases was lower than agro-chemicals such as tebuconazole and metalaxyl. Control efficacy of brown patch, Pythium and dollar spot by the biological agent was 57.4%, 40.4%, 61.5~87%, respectively. 5. Growth, color and texture of creeping bentgrass were not differ significantly between AF-2001 treatment and untreated control.

• Korean Journal Plant Pathology
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• v.10 no.2
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• pp.112-118
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• 1994

Forth microbial isolates out of 167 isolates from the soil of controlled cultivation areas inhibited mycelial growth of Rhizoctonia solani AG2-1 causing the strawberry bud rot in vitro. Among the isolates, Kr013 and Kr020 showed suppressive effect to R. solani AG2-1 on seedlings of chinese cabbage treated by root immersion, charcoal carrier granule and drenching on 1.0% infested soil in pot. Furthemore, the corresponding effect was also revealed when the charcoal carrier granule of the isolates were treated on the seedling of strawberry that were planted on the planting hole in pot. To examine the effects of biological control in green house, it had been tested the infection rates by using two different treatments. First, the strawberry runner were planted on the nursery soil mixed with 20% charcoal carrier granule of Kr013 and Kr020 isolate respectively, and grown for 20 days before transplanting. Then the young plants form the mother plant were separated and transplanted on the 1.0% infested soil. Another method was that the charcoal carrier of Kr013 and Kr020 isolates applied to planting hole of 1.0% infested soil just before transplanting. Then the young plants were grown for 20 days on the sterilized nursery soil before transplanting. From the results, the effects of biological control was significantly higher on former treatment (e.g. the infection rates were 7.3 and 5.7%, respectively) than on the latter treatment (e.g. the corresponding value were 16.7 and 15.7%, respectively). The antagonistic isolates of Kr013 and Kr020 were respectively identified as Pseudomonas cepacia with the similarity of 55.0% and 60.0% by using the Biolog GN Microplate system.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.52-58
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• 2013

Fusarium head blight (FHB) caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed.

• Korean Journal of Pharmacognosy
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• v.14 no.2
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• pp.51-59
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• 1983

Experimental studies were made with Melilotus officinalis extract which was extracted from flowers and leaves of Melilotus officinalis Dsr. (Leguminosae). In this paper, acute toxicity, analgesic action, prolongation of hypnosis time by induced pentobarbital-Nain mice, antiinflammatory effect in rats and effects on isolated intestines of mice and rats were studied, The result was as follows; 1. Very low toxicity in mice. 2. Analgesic action was recognized markedly in mice. 3. Prolongation of hypnosis time induced by pentobarbital-Na in mice was shown. 4. Relaxing action was shown on the isolated ileum in mice and antagonistic action was seen on $BaCl_2-induced$ contraction of the ileum that the relaxing effect of the intestinal smooth muscle was recognized. 5.Antiinflammatory effect was shown markedly in mice. 6.Hypotensive and vaso-dilating actions due to the vascular smooth muscle relaxation were noted in rabbits.

• Mycobiology
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• v.28 no.4
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• pp.180-184
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• 2000

In order to find an environment-friendly method to suppress astragal stem rot caused by the isolates of Rhizoctonia solani AG 1 and AG 4, we tested an antagonistic fungus Gliocladium virens G1 was evaluated as a biocontrol agent and estimated inorganic compounds and organic materials were tested for their effect of the disease suppression. G. virens G1 effectively inhibited mycelial growth in a dual culture and caused mycelial lysis in the culture filtrate. No adverse effect was observed when examined for seed germination and seedling growth. Promoted seedling growth was observed with the seed treatment. Seeds of astragal plant were germinated higher in the sterile soil than the natural soil. Of 14 inorganics tested, alum, aluminum sulfate and calcium oxide significantly suppressed the mycelial growth and sclerotial germination. Milled pine bark and oak sawdust also suppressed the mycelial growth. Soil amended with 1% of G. virens G1 composted with pine bark (w/v) significantly controlled astragal stem rot in the glasshouse experiments.

• Asian Journal of Turfgrass Science
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• v.13 no.3
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• pp.131-138
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• 1999

A synergistic effect of biocontrol agent and chemicals on control of the large patch on turfgrass caused by Rhizoctonia solani AG2-2 was evaluated. Chemicals; mepronil, toclofos-methyl and iprodione inhibited 90∼100% mycelial growth of R. solani AG1 and AG2-2 in vitro. While on the other, the chemicals inhibited only 0∼5%, 18∼46% and 30∼67% of mycelial growth of the antagonists, respectively. In field application, toclofos-methyl was the best to suppress the disease in single application, however, the combination of mepronil and T. viride 41D showed highest disease control effect among combinations of antagonists and chemicals. Effect of the combination of mepronil and T. viride 41D was similar to that of toclofos-methyl and T. viride 41D stage of disease development, but became higher in six week late. Results indicated that the combined application of selected antagonistic agent and chemical increased control efficasy of turgrass large patch.

• 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.

• Mycobiology
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• v.33 no.1
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• pp.19-22
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• 2005

We investigated the effect of nitrogen fixing Azotobacter bioinoculant on the mycelial growth and the rate of substrate utilization by Pleurotus eous. The synergistic or antagonistic role of the microorganism during dual culturing with the mushroom or the competitor molds Trichoderma viride, and Trichoderma reesi was studied. Azotobacter was inhibitory to the molds, which are competitive to the mushroom in the seed spawn substrate, but was synergistic towards the mushroom. The growth, substrate utilization potential as total nitrogen content and cellulase enzyme activities of the mushroom in the seed spawn substrate were also enhanced in the presence of the bioinoculant at lower inoculum concentrations, upto 5 ml broth culture per spawn bottle.

• Biomolecules & Therapeutics
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• v.9 no.1
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• pp.20-25
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• 2001

In this study we fed control diet and tryptophan supplemented diets containing 0.35% tryptophan to ICR mice for 2 weeks. The concentrations of serotonin and 5-HIAA were changed by injection of the serotonin synthesis inhibitor, p-CPA and the serotonin precursor, serotoninP and the change of brain serotonin concentration negatively correlated with that of pain sensitivity, and p-CPA and serotoninP also changed the analgesic effect of morphine. The injection of naloxone, the opiate antagonist, resulted in an increase in the writhing frequency, but its antagonistic effect was not significant. The concentration of 5-HIAA elevated in mice brain at least 3hr after administration of morphine hydroxide indicates that the changes in brain serotonin metabolism may be associated with the acute effects of morphine analgesia. In short, these results not only suggest that tryptophan supplemented diet suppress pain sensitivity in mice, but also indicate that at least in part analgesic mechanism of serotonin may be associated with morphine analgesia.