• Journal of Aquaculture
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• v.16 no.3
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• pp.196-201
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• 2003

Sessile organisms such as the oyster Crassostrea gigas have been given much attention as a potential biomonitoring indicator to assess the impact of toxicants on aquatic organism. In this study, we exposed cells isolated from gill of oyster (Crassostrea gigas) to hydrogen peroxide in vitro. In addition oysters were in vivo exposed to pyrene and benzo(a)pyrene at various concentrations for 2 weeks. Comet assay was used to detect DNA single strand breaks and to investigate the application of this technique as a tool for aquatic biomonitoring. Hydrogen peroxide increased DNA single strand break with increasing concentration after 30 minutes exposure in vitro. Pyrene and benzo(a)pyrene caused DNA damage only at very high concentration (100 $\mu\textrm{g}$/L or 1000 $\mu\textrm{g}$/L) at two week exposure in vivo. DNA damage was relatively higher at hemocyte than at gill. It suggested that metabolized PAHs are transferred to hemolymph from digestive gland which have a relatively high enzyme activity, and attacked the DNA of hemocyte, while gill accumulated PAHs without degrading them to their metabolites due to low enzyme activity at gill. Both in vitro and in vivo exposure experiments showed that the comet assay is an effective tool on screening whether the organism are exposed to genotoxic contaminants.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.416-423
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• 2000

There is a growing concern that a wide variety of chemicals released into the environment can disrupt the endocrine system of fish, wildlife and humans. Endocrine disrupting chemicals (EDCs) include pesticides such as DDT lindane and atrazine, the food packaging chemicals, phthalates and bisphenol A, alkylphenol ethoxylate detergents and the chemical industry by-products, dioxins. Xenoestrogens in the environment have been argued about health risk, because of estrogen mimetic chemicals are exposed only small amounts to human. A number of in vivo and in vitro assays are now in use to assess the activity of xenoestrogens in the environment. A human breast cancer cell line (MCF-7) was used to develop in vitro screening assay for the detection of xenoestrogenic environmental pollutants. The E-SCREEN (MCF7-BUS) assay is proposed as a reliable, easy and rapid-to-perform method. To optimize and validate this method before it can be used routinely, several phenol compounds and pesticides suspected to be estrogenic were tested using I-SCREEN assay. The results showed that this method is a valuable tool for screening potential estrogen-mimicking environmental pollutants and quantitative determination of estrogeniciy.

• The Korean Journal of Food & Health Convergence
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• v.4 no.4
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• pp.10-17
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• 2018

Capsicum frutescen is known in Sudan, is one of the most commonly used pepper species in cooking and in Sudanese folk medicine. The present study was conducted to investigate antimicrobial (bacteria and fungi) and cytotoxicity (Brine Shrimp Lethality Test) of methanolic extract of Capsicum frutescen (fruits). The extract have been tested in the present study to investigate the in vitro potential effects against Gram positive, Gram negative bacteria and fungi. The selected organisms were Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia and Candida albicans using the cup plate agar diffusion method. The methanol extract of Capsicum frutescen (fruits) exhibited inhibitory effects against Escherichia coli with zone of inhibition (23 mm) and Klebsiella pneumonia with zone of inhibition (17 mm). The phytochemical screening revealed the presence of Tannins, Saponin, Alkaloids, Anthroquinoles and Terpenoids. The Cytotoxicity of methanolic extract of Capsicum frutescens was $LD_{50}$ $64.68{\mu}g/ml$. The activity and presence of compounds known to be biologically active are a validation for the use of Capsicum as a food ingredient and as a therapeutic element of traditional medicine.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.68-73
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• 2005

Epi-xanthatin analogs containing hydrophilic substituents such as carboxylic acid, alcohol, morpholine, amino acid, and glucose derivatives were synthesized and their in vitro cytotoxicity and in vivo antitumor activity were evaluated. The target compounds were generally cytotoxic against tumor cell lines of human origin with $ED_{50}$ values of $0.1{\sim}30{\mu}g/ml$, except the highly hydrophilic analog 6 containing aspartic acid. Contrary to the potent cytotoxicity weakly hydrophilic analogs 2 and 8 were not active in vivo, or even toxic to the test animals. As a result, hydrophilic analog of epi-xanthatin did not show in vitro cytotoxicity and hydrophobic analogs did not show in vivo antitumor activity, thus it is presumed that amphiphilic analogs or those with medium hydrophilicity would exhibit the antitumor potency in vivo.

• Korean Journal of Veterinary Research
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• v.52 no.2
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• pp.105-113
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• 2012

In this study, a medicinal herbal plant, Meliae fructus, was examined and screened for anti-Helicobacter (H.) pylori activity. Seventy percent ethanol was used for herbal extraction. For anti-H. pylori activity screening, inhibitory zone tests as an in vitro assay and in vivo study using a Mongolian gerbil (Meriones unguiculatus) model were performed. Also, the safety of herbal compounds was evaluated by animal study. As a result of inhibitory zone test, Meliae fructus extract demonstrated strong anti-H. pylori activities. Also, as results of in vivo animal studies, Meliae fructus demonstrated strong therapeutic effects against H. pylori infection according to the criteria of histological examination and rapid urease test. As results of the safety study, after 28 days treatment of the Meliae fructus extract, the animals were not detected any grossly and histological changes. These results demonstrate that it can be successfully cured against H. pylori infection and protected from H. pylori-induced pathology with Meliae fructus. It could be a promising native herbal treatment for patients with gastric complaints including gastric ulcer caused by H. pylori.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.297-301
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• 1996

옥수수 깜부기병균에 대한 살균제 활성검정시 실내 검정과 온실 유묘검정과의 상관정도를 조사하기 위하여 5가지 살균제를 공시하여 실내와 온실에서 깜부기병균에 대한 억제효과를 비교하였다. 실내검정방법으로 사용한 최소생육억제농도법, 저지원법, 소생자발아검정법의 결과는 모두 온실유묘검정에서 얻어진 결과와 상관이 높았으며 특히 저지원법은 유묘검정결과와 매우 높은 상관관계를 보였다. 따라서 저지원법과 같은 실내검정방법은 대량의 활성검정시 간이검정방법으로 유용하게 이용될 수 있으리라 생각된다.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.110-114
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• 2004

Through in vitro screening for biocontrol agents (BCAs) against Streptomyces scabiei causing potato (Solanum tuberosum) common scab, 19 streptomycete and 17 fungal isolates with antagonistic activity were selected as BCA candidates. For the selection of BCA candidates which are highly resistant to 10 kinds of antibiotics or pesticides, chemical susceptibility testing was initially performed in vitro. A remarkable degree of variation in susceptibility to antibiotics or pesticides was observed among the isolates tested. Streptomycete A020645 isolate was highly resistant to all the tested chemicals except neomycin up to 5,000 ppm. On the other hand, out of 36 antagonistic microbes subjected to in vivo pot tests using cultivar Daejima, four streptomycete isolates namely, A020645, A010321, A010564, and A020973, showed high antagonistic activity with >60% and 55% control value, respectively, and high chemical resistance to 10 kinds of chemicals. Therefore, these isolates were selected as potential BCAs for the control of potato common scab.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.02a
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• pp.84-84
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• 2001

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.135.1-135.1
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• 2000

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.105-112
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• 1997

Didymella bryoniae, gummy stem blight fungus of cucurbits, has been known not to produce its pycnidium in vitro without irradiation. Various methods for producing pycnidiospores of the fungus as an inoculum have been used. However, those methods have not been verified in terms of efficiency of the productivity, activity and synchronous maturation of the inoculum. Therefore, a pycnidiospore production method in vitro that is highly reliable and reproducible has to be developed to obtain a large amount of inoculum for screening disease resistant varieties or effective fungicides. Here we standardized a mass-production technique for pycnidiospores of D. bryoniae in vitro by comprehensively finding the optimal conditions such as kinds and thickness of cultural medium, growing temperature, and quality and duration of irradiation as well as examining the activity and pathogenicity of the pycnidiospores reproduced. In brief, mycelial colony on the PDA plate was cultured at 26$^{\circ}C$ for 2 days under the darkness, and then the plate was irradiated under the UV light (12 hr/a day) for 2~3 days at the same temperature(26$^{\circ}C$). Two days after UV irradiation, a great number of pycnidia was simultaneously formed. This plate was subjected to darkness again for 4~5 days to mature pycnidiospores. We could obtain a large amount of inoculum that is synchronously matured in a short period of time through the above procedures.