• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.49-55
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• 2001

For the production of probiotic feed enriched with viable yeasts, aerobic liquid culture of Kluyveromyces marxianus was attempted in pulverized residual food wastes. After the preliminary shaking culture result, the liquid food wastes was added with urea($0.5g/{\ell}$), o-phosphate($0.4g/{\ell}$ ), molasses($4g/{\ell}$), and yeast extract($1g/{\ell}$), and the fermentation was carried out in 2-litre jar fermenter. In 12 hours of aerobic mixed culture with Aspersillus oryzae, viable cell count of the yeast reached to the number of $1.4{\times}10^{10}/{\ell}$ in the cultured medium.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.95-108
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• 2020

To develop an environment-friendly fungicide for controlling tomato wilt diseases, antifungal active substance was isolated Rheum australe D. Don roots against Fusarium oxysporum f. sp. lycopersici, a pathogen of tomato wilt, in this study. Methanol extract obtained from Rheum australe roots was successively fractionated with hexane, chloroform, ethyl acetate, butanol and water. The ethyl acetate fraction, which showed the highest antifungal activity, was separated by column chromatography, and 60 subfractions were obtained. The 60 subfractions were anlayzed for antifungal activities by bioassay. The active compound was identified as 5-[(E)-2- (3-hydroxy-4-methoxyphenyl)ethenyl]benzene-1,3-diol (rhapontigenin) by NMR and GC-MS analysis. As a result of testing antifungal activity of rhapontigenin against Fusarium oxysporum, EC₅₀ of rhapontigenin was showed strong antifungal activity at 7.48 mg/L. Therefore, this study showed that the Rheum australe roots extract can be a potential candidate which is a environment-friendly fungicide against Fusarium oxysporum.

• Journal of Life Science
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• v.10 no.4
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• pp.368-373
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• 2000

Enteroviruses in the environment pose a public health risk because they can be transmitted via the fecal-oral route through contaminated water, and low numbers are able to initiate an infection in humans. Because the levels of viruses typically found in environmental water and drinking water are low, they must be concentrated from hundreds to thousands of liters of water. Therefore, the main goal of this study was the development of a rapid, simple and efficient procedure to concentrate, isolate and detect enteroviruses from environmental water samples. Viruses were first concentrated by adsorption to 1 MDS cartridge filter and then eluted with approximately 0.5 liter of 1.5% beef extract/0.05M glycin(pH 9.4). In this study, several procedures to concentrate and purify intact viruses from beef extract obtained from the adsorbent filters were tested. Among them, organic floccuration was the best reliable method for reconcentration. sample volume could be reduced to 200∼400 folds and the efficiency of virus recovery through the procedure was over 72%. Finally, the samples were filtered through a membrane disk filter and then analyzed by either the plaque assay or combined cell culture-polymerase chain reaction.

• YAKHAK HOEJI
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• v.55 no.3
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• pp.251-259
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• 2011

Cigarette smoke condensate (CSC) is known to be carcinogenic compound. CSC contains many organic compounds such as polycyclic aromatic hydrocarbons (PAHs), and heterocyclic amine compounds (HCAs). Reactive oxygen species (ROS) are also generated and induce oxidative DNA damage during the metabolism of CSC. The rat microsome mediated and DNA repair enzyme treated comet assays together with conventional comet assay were performed to evaluate the mechanisms of CSC genotoxicity. The organic extract of CSC induced oxidative and microsome mediated DNA damage. Vitamin C as a model antioxidant reduced DNA damage in endonuclease III treated comet assay. One of flavonoid, galangin as a CYP1A1 inhibitor, reduced DNA damage in the presence of S-9 mixture. The ethanol extracts of the mixed vegetables (BV) or the mixed fruits (BF) showed potent inhibitory effects against CSC induced DNA damage with oxidative DNA lesions and in the prescence of S-9 mixture. These results indicate that BV and BF could prevent CSC-induced cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P450 in mammalian cells.

• Preventive Nutrition and Food Science
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• v.12 no.4
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• pp.267-272
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• 2007

The objective of this study was to investigate antioxidant activities of Panax ginseng extracted with various solvents including n-hexane, chloroform, EtOAC, n-butanol and water. Among the various ginseng extracts, ethyl acetate (EtOAC) extracts showed the most powerful scavenging activities against DPPH radicals. Among the other solvent extracts, the butanol extract seemed relatively more effective in scavenging activity, followed by chloroform, water and hexane extracts. Moreover, the highest reducing power and ferrous ion chelating activity were found in the EtOAC extract followed by other extracts of ginseng. EtOAC extracts, which exhibited the best antioxidant activities of all solvent extracts of ginseng, possessed higher concentrations of total phenolics (777.61 mg/100 g) than other extracts. These results suggest that EtOAC extracts of ginseng (P. ginseng C.A. Meyer) have the most effective antioxidant capacity compared to n-hexane, chloroform, n-butanol and water tested in this study, and has important applications for the pharmaceutical and food industries.

• Mycobiology
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• v.44 no.4
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• pp.338-342
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• 2016

The culture filtrate of Lentinula edodes shows potent antimicrobial activity against the plant pathogenic bacteria Ralstonia solanacearum. Bioassay-guided fractionation was conducted using Diaion HP-20 column chromatography, and the insoluble active compound was not adsorbed on the resin. Further fractionation by high-performance liquid chromatography (HPLC) suggested that the active compounds were organic acids. Nine organic acids were detected in the culture filtrate of L. edodes; oxalic acid was the major component and exhibited antibacterial activity against nine different phytopathogenic bacteria. Quantitative analysis by HPLC revealed that the content of oxalic acid was higher in the water extract from spent mushroom substrate than in liquid culture. This suggests that the water extract of spent L. edodes substrate is an eco-friendly control agent for plant diseases.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.2
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• pp.109-116
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• 1988

Oriental tobacco (KA 101) was transplanted from Mar. 25 to May 5 with 10 days interval in 1984 and 1985, and its agronomic characteristics, chemical properties ware compared to determine the Proper transplanting time of aromatic tobacco In Korea. As the transplanting was delayed, days to flowering of plant was shortened, length and width of largest leaf, leaf area index tended to decrease. Yield was highest for the Apr. 5th transplanting followed by Mar. 25th planting, then decreased as the planting date was delayed. Quality by price decreased as the transplanting was delayed later than Apr. 25. Delaying transplanting increased nicotine, total nitrogen and ash content, but decreased reducing sugar and petroleum ether extract of cured leaves, The content of volatile organic acids such as 3-methyl pentanoic acid was lower when it was transplanted later than Apr. 25th. Neophytadiene content increased as the transplanting was delayed, but there were no trends with the content of alcohols, aldehydes esters and ketones. Several quality indices including the ratio between the content of volatile organic acids plus petroleum ether extract and ash content plus pH was higher for the Apr. 5th transplanting.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.441-451
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• 2023

Golden apple snails (Pomacea canaliculata) were first introduced as food for high protein source and were later widely used as a means of weeding in rice paddies by taking of their vigorous feeding habits. Since 2000, the wintering of golden snails has been found and damage to rice plants occurred by them. To prevent damage, a means to control golden apple snails has become necessary. In this study, we investigated the possibility of eco-friendly control of golden apple snail by using Styrax japonicus fruit that grow naturally in-country. When the ethanol extract of the fruit was treated for controlling golden apple snail, the effect of over 90% was confirmed at 250 and 125 ppm after 1 day. Using UPLC MS analysis, two major compounds, dihydrorotenone known as a natural pesticide was detected. The molluscicidal activity was confrimed at 50 ppm of dihydrorotenone standard material. Our results showed that the possibility of developing an eco-friendly agent of golden apple snail using S. japonicus fruit was confirmed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.2
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• pp.189-194
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• 2015

Streptococcus mutans (S. mutans) is one of the most important bacteria in the formation of dental plaque and dental caries. S. mutans adheres to an acquired pellicle formed on the tooth surface, and aggregates with many oral bacteria, and initiates plaque formation by synthesizing glucan from sucrose, which is catalyzed by glucosyltransferases. S. mutans metabolizes the dietary sugar to the organic acids. The organic acids demineralize tooth surface and result in dental caries. Galla Chinensis have been traditionally used for stopping bleeding of gingiva, removing edema and halitosis, drainage, fixing the teeth and as an antiphlogistic agent. In previous reports, antibacterial effects of Galla Chinensis have been investigated whereas anti-cariogenic effects is still not examined enough. Therefore we tested effects of ethanol extracts of Galla Chinensis on the cariogenic properties such as the growth, acid production, adhesion, and insoluble glucan synthesis of S. mutans. In the result, ethanol extracts of Galla Chinensis showed the inhibition of S. mutans growth and organic acids production over 0.031 mg/ml concentrations. The adhesion of S. mutans to Saliva-coated Hydroxyapatite beads S-HAs has decreased with the increase of concentration of ethanol extracts of Galla Chinensis. And it seems to have adhesion inhibitory effect in concentration of over 0.25 mg/ml. It gives us the result that Galla Chinensis have anti-caries effects. But ethanol extract of Galla Chinensis didn't have inhibitory effect on insoluble glucan synthesis. Preliminary phytochemical analysis of the ethanol extract of Galla Chinensis showed strong phenolic compounds, medium steroids & terpenoids and glycosides, and weak organic acids and peptides. These results suggest that the ethanol extracts of Galla Chinensis may have anti-cariogenic properties, which may be able to be related with strong phenolic compounds.

• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.85-94
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• 1986

To study fate of carbofuran in paddy system, C-14 labelled carbofuran was applied to paddy water containing rice seedlings and time course study was made on the distribution, metabolism and chemical transformation of the systemic insecticide. Carbofuran was readily absorbed by plant root and translocated to shoots where most of the radioactivities were confined to leaf tips. The fact that gradual increases in radioactivities of both aqueous phase extracts and non-extractable fractions of plants (shoots and root) increased with incubation is taken as an evidence that reactions (phase I and II) proceed in rice plants. Carbofuran and its five metabolites were all detected by TLC in organic phase extracts of paddy plants or soil. Evidence was put forward that carbofuran and its five metabolites were all identified as aglycones of conjugates. 7-benzofuranol and 3-hydroxycarbofuran were the most abundant aglycones. Soil microbes appears to have little effects on the metabolism of carbofuran. They increased radioactivity of non-extractable fraction and reduced that of organic phase extracts of paddy soil.