• 미생물과산업
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• 제19권4호
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• pp.14-26
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• 1993

Optimizing protein production in recombinant E. coli strains involves manipulation of genetic and environmental factors. In designing a production system, attention must be paid to gene expression efficiency, culture conditions and bioreactor configuration. Although not much emphasis was given to the physiology of host strains in this review, an understanding of the relationship between the physiology of host cell growth and the overproduction of a cloned gene protein is of primary importance to the improvement of the recombinant fermentation processes. Sometimes it is desirable to make use of gene fusion systems, e.g. protein A, polypeptide, gutathione-S-transferase, or pneumococcal murein hydrolase fusion, to facilitate protein purification.

• 대한의생명과학회지
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• 제12권1호
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• pp.49-52
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• 2006

To elucidate the effect of antioxidant complex containing $\beta-carotene$, vitamin E, vitamin C, Ginkgo Biloba leaf extract and selenium on oxygen :tree radical production and detoxification system, rats were fed normal diet and normal diet with antioxidant complex 0.1%, 0.3% and 0.5% for 3 weeks. Feed efficiency ratio, changes in body weight, weight gain and amounts of feces of rat are similar in four groups. Liver weight per body weight and hepatic lipid peroxide weight increased in 0.5% group. However, hepatic glutathione contents in all antioxidant complex added groups were significantly increased compare with normal control group. On the other hand, the activity of xanthine oxidase was a little increased due to the amounts of antioxidant complex. Superoxide dismutase and gutathione peroxidase activity of 0.1% antioxidant complex added group were increased about $10{\sim}20%$ in comparison to normal control group. These results suggest that the supplementation of antioxidant complex 0.1% to basal diet may reduce the hepatic damage caused by free radicals.

• Biomolecules & Therapeutics
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• 제10권4호
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• pp.287-292
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• 2002

To find new inhibitory effects from oriental drugs, Albizziae root was extracted in methanol and the extracted was stepwisely fractionated by hexane, chloroform, ethylacetate, butanol and water. In cytotoxic effect of Albizziae root fractions against cancer cell lines including human hepatoma cells(HepG2) were investigated. Expecially the butanol fraction exhibited a inhibition effects on the growth of human hepatoma cells(HepG2). It inhibited of HepG2 cells with the value of IC50. The activities of qutathione after B(a)P treatment were markedly decreased than control, but those levels were increased by the treatment of Albizziae root methanol fraction. The activity of glutathione-S-transferase after B(a)P treatment were markedly decreased than control, but those levels were increased by the treatment of Albizziae root methanol traction. Induction of phase II enzymes is a major mechanism of chemoprevention. The induction levels of quinone reductase(QR) activity in cultured murine hepatoma(Hepa IcIc7)cell by methanol extract of Albizziae root were measured. Among the tested tractions, the extracts of butanol were found to induce QR activities over 2.8 fold than control. These results suggest that Albizziae root has chemopreventive Potential by inducing QR activities and GST levels and increasing GSH

• Journal of Nutrition and Health
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• 제35권2호
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• pp.183-191
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• 2002

The purpose of this study was to investigate the effect of dietary mushroom powder on blood glucose levels, seam lipid levels, glucose 6-phosphtase (G6Pase), thiobarbituric arid reactive substance (TBARS) and glutathione enzymes in diabetic rats treated with streptozotocin (STZ). Four groups of rats (Sprague-Dawley male rats, 180-200 g) were fed as follows: normal rats were fed a control diet (C), diabetic rats were file a control diet (CD), normal fats were fed a mushroom powder diet (M), and diabetic rals were find mushroom powder diet (MD). Diabetes was induced by single injection of streptozotocin (60 mg/kg B.W.). The animals were fed ad libium each of the experimental diets for five weeks. Food and water intake was determined every day. Blood glucose and serum total cholesterol levels were determined every week. After five weeks, the rats were sacrificed and blood glucose, serum total cholesterol, triglyceride levels and glutathione enzymes were measured. HDL-cholesterol levels were analyzed and LDL-cholesterol concentrations were calculated by equation. There was body weight loss in the diabetic rats, but the MD group showed less body weight loss than the CD group. Blood glucose and serum total cholesterol level of the MD group were lower than those of the CD group (p < 0.05). Also, serum total cholesterol of the M group was lower than that of the C group (p < 0.05). But the serum triglyceride level of the diabetic rats (CD and MD) was higher than that of the normal rats (C and M). However, there was no significant difference between the control diet group and the mushroom diet group. Serum HDL-cholesterol levels of the C group and CD group were higher than that of the M group (p < 0.05), and the MD group was not significantly different. But the serum LDL-cholesterol levels of the M group were lower than those of the C group (p < 0.05). Activity of hepatic microsomal G6Pase significantly increased in the CD and MD, reaching levels higher than those of the C and M groups. Hepateic gutathione S-transferase (GST, glutathione reductase (GR) and glutathione peroxidase (GPX) activity was not significant. But renal GST, GR and GPX activity in the MD group was lower than that of the CD group (p < 0.05). These results suggest that dietary mushroom reduces renal disorders such as oxidation and aging of tissue. In conclusion, dietary mushroom groups reduced blood glucose and cholesterol levels in STZ-induced diabetic rats and renal glutathione enzymes activity was averted in diabetic rats.

• 한국식품위생안전성학회지
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• 제25권3호
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• pp.269-277
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• 2010

본 연구에서는 azoxymethane (AOM)과 dextran sodium sulfate (DSS)로 유도된 대장 발암과정에 대한 셀레늄의 방어 효과를 조사하였다. 셀레늄 결핍(0.02 ppm Se), 정상(0.1 ppm Se), 과다(0.5 ppm Se)사료를 12주간 식이로 급여하여 혈액검사와 대장암 발생의 초기단계인 aberrant crypt foci (ACF)수를 측정했으며, 암 발생율을 조사하였다. ICP-AES를 사용하여 간의 셀레늄 농도를 측정하였으며, 또한 셀레늄포함 항산화효소인 glutathione peroxidase (GPx) 활성을 알아보았다. 또한 TUNEL assay와 PCNA, $\beta$-catenin에 대한 면역조직 염색을 수행하였다. ACF 수 및 종양 발생률에 있어서, 셀레늄과다사료를 급여한 군이 정상셀레늄사료를 급여한 군보다 낮았으며, 셀레늄결핍사료를 급여한 군은 오히려 ACF 수 및 종양 발생률이 높았다. GPx 활성은 셀레늄의 섭취가 과다한 군에서 높게 나타났으며, 이 때, TUNEL에서 apoptotic positive cell이 증가하는 것을 확인했다. 또한 셀레늄의 섭취가 과다한 군에서 PCNA와 $\beta$-catenin의 발현이 감소됨을 볼 수 있었다. 본 마우스 모델실험에서 셀레늄은 여러 기전에 의해 대장암 발생을 억제할 수 있을 것으로 사료된다.