• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.551-563
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• 2022

L-asparaginase (E.C. 3.5.1.1) purified from bacterial cells is widely used in the food industry, as well as in the treatment of childhood acute lymphoblastic leukemia. In the present study, the Burkholderia pseudomallei L-asparaginase gene was cloned into the pGEX-2T DNA plasmid, expressed in E. coli BL21 (DE3) pLysS, and purified to homogeneity using Glutathione Sepharose chromatography with 7.26 purification fold and 16.01% recovery. The purified enzyme exhibited a molecular weight of ~33.6 kDa with SDS-PAGE and showed maximal activity at 50℃ and pH 8.0. It retained 95.1, 89.6%, and 70.2% initial activity after 60 min at 30℃, 40℃, and 50℃, respectively. The enzyme reserved its activity at 30℃ and 37℃ up to 24 h. The enzyme had optimum pH of 8 and reserved 50% activity up to 24 h. The recombinant enzyme showed the highest substrate specificity towards L-asparaginase substrate, while no detectable specificity was observed for L-glutamine, urea, and acrylamide at 10 mM concentration. THP-1, a human leukemia cell line, displayed significant morphological alterations after being treated with recombinant L-asparaginase and the IC₅₀ of the purified enzyme was recorded as 0.8 IU. Furthermore, the purified recombinant Lasparaginase improved cytotoxicity in liver cancer HepG2 and breast cancer MCF-7 cell lines, with IC₅₀ values of 1.53 and 18 IU, respectively.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.05a
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• pp.130.2-130.2
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• 2003

• Journal of Food Hygiene and Safety
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• v.9 no.1
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• pp.15-21
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• 1994

The mutagenic activity of four phenothiazine derivatives such as chlorpromazine, perphenazine, trifluoperazine and thioridazine in conjunction with UV-A irradiation or not based on the Ames plate incorporation test in the presence and absence of liver microsomal enzyme(S9 fraction). None of these compounds and their photo-excited were detected as mutagen in the Salmonella microsome assay with TA 98 and TA 100.

• Journal of Ginseng Research
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• v.16 no.3
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• pp.190-197
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• 1992

The increased level of glucose, ketone bodies, non-esterified fatty acids and lactate in blood, decrease of glycogen content, phosphofructokinase activities and glucokinase activity and the increased level of glucose-6-phosphatase activity in the liver of streptozotocin injected rats were significantly moderated by ginseng saponin administration. It is not likely, however, that the hypoglycomic action of ginseng saponin might be due to their direct action on enzyme activities, since the saponin effect of servers enzymes in vitro was not enough to explain such an appreciable hypoglycemic activity of the saponin in streptozotocin induced diabetic rats, for which much work have to be done.

• Archives of Pharmacal Research
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• v.13 no.2
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• pp.132-135
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• 1990

Polyhydroxystilbenes including resveratrol were reported to competitively inhibit monoamine oxidase-A-without structural relation with substrates and cynthetic inhibitors for the enzyme. We attempt to explore a plausible mechanism for their inhibitory activity on MAO-A. All the polyhydroxystilbenes tested showed the antioxidant activity on liver homogenate. Furthermore, the antioxidant activity turned out to closely correlate with the MAO-A inhibitory activity.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.166-166
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this is detoxification and metabolizing more than 50% clinical drugs in use. The transcription of CYP3A4 is regulated by the Pregnenolone X receptor (PXR),of which human form is Steroid and Xenobiotics receptor (SXR).(omitted)

• Proceedings of the PSK Conference
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• 2003.10a
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• pp.70-70
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• 2003

In mammalians, ketone bodies (acetoacetate, D(-)-3-hydroxybutyrate and acetone) are generated mainly in the liver via the 3-hydroxy-3-methylglutaryl-CoA pathway, carried to and utilized in extrahepatic tissues as an energy source during starvation and diabetes in particular due to their overproduction as the consequence of elevated fatty acid oxidation and lowered glucose metabolism. (omitted)

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.8
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• pp.1169-1177
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• 2012

An experiment was conducted to determine the effects of different amounts of dietary linoleic acid (LA) on growth performance, serum biochemical traits, meat quality, fatty acids composition of muscle and liver, acetyl-CoA carboxylase (ACC) and carnitine palmitoyl transferase 1 (CPT 1) mRNA expression in the liver of 9 wks old to 13 wks old growing meat rabbits. One hundred and fifty 9 wks old meat rabbits were allocated to individual cages and randomly divided into five groups. Animals in each group were fed with a diet with the following LA addition concentrations: 0, 3, 6, 9 and 12 g/kg diet (as-fed basis) and LA concentrations were 0.84, 1.21, 1.34, 1.61 and 1.80% in the diet, respectively. The results showed as follows: the dietary LA levels significantly affected muscle color of LL included $a^*$ and $b^*$ of experimental rabbits (p<0.05). The linear effect of LA on serum high density lipoprotein cholesterol was obtained (p = 0.0119). The saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) contents of LL decreased and the polyunsaturated fatty acids (PUFAs) content of LL increased with dietary LA increase (p<0.0001). The PUFA n-6 content and PUFA n-3 content in the LL was significantly affected by the dietary LA levels (p<0.01, p<0.05). The MUFAs content in the liver decreased and the PUFAs contents in the liver increased with dietary LA increase (p<0.0001). The PUFA n-6 content and the PUFA n-6/n-3 ratio in the liver increased and PUFA n-3 content in the liver decreased with dietary LA increase (p<0.01). The linear effect of LA on CPT 1 mRNA expression in the liver was obtained (p = 0.0081). In summary, dietary LA addition had significant effects on liver and muscle fatty acid composition (increased PUFAs) of 9 wks old to 13 wks old growing meat rabbits, but had little effects on growth performance, meat physical traits and mRNA expression of liver relative enzyme of experimental rabbits.

• Applied Microscopy
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• v.31 no.1
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• pp.37-47
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• 2001

In order to investigate a pathogenesis of liver damage induced by skin burn, thermal injury was induced by scald burn on entirely dorsal surface in rats (total burn surface area $20\sim25\%$) except for inhalated injury. At 5 and 24 h after scald burn, biochemical assay and morphological changes in serum and liver tissue were examined. Skin burn increased liver weight (% of body weight, p<0.05) and the activity of serum aniline amino-transferase (ALT, p<0.05), in addition, the activity of xanthine oxidase (XO), an enzyme of oxygen free radical generating system, was elevated (p<0.01) in serum, but not in skin and in liver. Postburn treatment of allopurinol intraperitoneally decreased liver weight, serum ALT activity and serum XO activity. Scald burn induced ultrastructurally swelling of endoplasmic reticulum, ribosome detachment, accumulation of lipid, dilatation of bile canaliculi and intercellular space, neutrophil infiltration, activation of Kupffer's cells and degeneration of hepatocytic microvilli. Futhermore , thermal injury decreased not only the protein concentration in plasma but also the number of intravascular leukocytes, that indicates induction of edema formation with protein exudation and inflammation by neutrophil infiltration into the internal organs. However allopurinol injection after burn inhibited post burn ultrastructural changes. These data suggest that acute dermal scald burn injury leads to liver damage, that is related to elevation of xanthine oxidase activity in serum. Xanthine oxidase may be a key role in the pathogenesis of liver damage induced by skin burn.

• Nutrition Research and Practice
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• v.4 no.2
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• pp.93-98
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• 2010

Our previous study demonstrated that methanolic extract of Chrysanthemum zawadskii Herbich var. latilobum Kitamura (Compositae) has the potential to induce detoxifying enzymes such as NAD(P)H:(quinone acceptor) oxidoreductase 1 (EC 1.6.99.2) (NQO1, QR) and glutathione S-transferase (GST). In this study we further fractionated methanolic extract of Chrysanthemum zawadskii and investigated the detoxifying enzyme-inducing potential of each fraction. The fraction (CZ-6) shown the highest QR-inducing activity was found to contain (+)-(3S,4S,5R,8S)-(E)-8-acetoxy-4-hydroxy-3-isovaleroyloxy-2-(hexa-2,4-diynyliden)-1,6-dioxaspiro [4,5] decane and increased QR enzyme activity in a dose-dependent manner. Furthermore, CZ-6 fraction caused a dose-dependent enhancement of luciferase activity in HepG2-C8 cells generated by stably transfecting antioxidant response element-luciferase gene construct, suggesting that it induces antioxidant/detoxifying enzymes through antioxidant response element (ARE)-mediated transcriptional activation of the relevant genes. Although CZ-6 fraction failed to induce hepatic QR in mice over the control, it restored QR activity suppressed by $CCl_4$ treatment to the control level. Hepatic injury induced by $CCl_4$ was also slightly protected by pretreatment with CZ-6. In conclusion, although CZ-6 fractionated from methanolic extract of Chrysanthemum zawadskii did not cause a significant QR induction in mice organs such as liver, kidney, and stomach, it showed protective effect from liver damage caused by $CCl_4$.