• Proceedings of the Korean Environmental Health Society Conference
• /
• 2001.04a
• /
• pp.119-119
• /
• 2001

• BMB Reports
• /
• v.41 no.3
• /
• pp.254-258
• /
• 2008

Lipase was purified from squid (Todarodes pacificus) liver in an attempt to investigate the possibility of applying the enzyme for biotechnological applications. Crude extract of squid liver was initially fractionated by the batch type ion exchange chromatography. The fraction containing lipase activity was further purified with an octyl-Sepharose column. Finally, lipase was purified by eluting active protein from a non-dissociating polyacrylamide gel after zymographic analysis. Molecular weight of the purified enzyme was determined to be 27 kDa by SDS-polyacrylamide gel electrophoresis. The enzyme showed the highest activity at a temperature range of $35-40^{\circ}C$ and at pH 8.0. The activity was almost completely inhibited at 1 mM concentration of $Hg^{2+}$ or $Cu^{2+}$ ion. Partial amino acid sequence of the enzyme was also determined.

• Toxicological Research
• /
• v.22 no.1
• /
• pp.39-45
• /
• 2006

As the antioxidant and free radical scavenger, glutathione (GSH) participates in the preservation of cellular redox status and defense against reactive oxygen species and xenobiotics. Glutamate-cysteine ligase (GCL; also known as ${\gamma}$-glutamylcysteine synthetase, EC 6.3.2.2) is the rate limiting enzyme in GSH synthesis. In the present study, the accurate method for determination of GCL activity in crude liver extracts was developed by measuring both ${\gamma}$-glutamylcysteine and GSH from cysteine in the presence of glutamate, glycine and an ATP-generating system. We added glycine to promote the conversion of ${\gamma}$-glutamylcysteine to GSH, and to minimize the possibility of ${\gamma}$-glutamylcysteine metabolism to cysteine and oxoproline by ${\gamma}$-glutamylcyclotransferase. We established optimal conditions and substrate concentrations for the enzyme assay, and verified that inhibition of GCL by GSH did not interfere with this assay. Therefore, this assay of hepatic GCL under optimal conditions could provide a more accurate measurement of this enzyme activity in the crude liver extracts.

• YAKHAK HOEJI
• /
• v.34 no.2
• /
• pp.112-116
• /
• 1990

8-Acyl-2-hydroxyphenzaine -5, 10-dioxides and 8-acyl-2-aminophenazine-5, 10-dioxides bearing n-butanoyl, n-hexanoyl and n-octanoyl groups were synthesized. It was attempted to observe the effect of phenazine dioxide derivatives on the hepatic xanthine oxidase activity in this study. As the activity of xanthine oxidase, the key enzyme in the generation of superoxide anion radical ($O_2$), was measured in the presence of phenazine dioxide derivatives, the action of 8-acyl-2-hydroxyphenazine-5,10-dioxide derivatives inhibited with increase of numbers of carbon atom bearing 8-acyl group. Moreover, when plotted on double reciprocal form, the Vmax value decrease as increase of numbers of carbon atom bearing acyl groups without affecting the Km value. However, the hepatic xanthine oxidase activity was not changed by 8-acyl-2-aminophenazine-5,10-dioxide derivatives.

• Korean Journal of Pharmacognosy
• /
• v.17 no.3
• /
• pp.189-194
• /
• 1986

The single acute treatment of mice with the steam distillate, non-volatile ether extract and methanol extract from mace, arils of Myristica fragrans(Myristicaceae) caused a significant prolongation of hexobarbital-induced narcosis, an increase in strychnine toxicity as well as a significant decrease in hepatic microsomal drug metabolizing enzyme activities. On seven daily consecutive administrations, however, the duration of narcosis was markedly shortened and significant increases in the hepatic enzyme activities were shown. From the non-volatile ether fraction, macelignan, a new lignan, mp $70{\sim}72^{\circ}$ was isolated as an active principle.

• Toxicological Research
• /
• v.14 no.3
• /
• pp.285-291
• /
• 1998

This study was designed to examine the effects of polyundaturated fatty acid(PUFA) from different sourecs on hepatic lipogenic enzyme and peroxisomal ${\beta}$-oxidation in murine hepatocarcinogenesis initiated by diethylnitrodamine (DEN). Male Sprague-Dawley rats were fed one of three diets containing 10%(w/w)fat; fish oil-corn oil blended(FO), corn oil-beef tallow-fish oil blended(CF), or corn oil-beef tallow-perilla oil blended (CP), from the gestation period. At 10 weeks, animals were received a single inraperitoneal injection of DEN (200mg/kg body weight), were subjected to two-thirds partial hepatectomy 3 weeks later and were sacrificed 8 weeks after DEN initiation. The areas of placental glutathione S-transferase (GST-P) positive foci were significantly smaller in rats fed fish oil containing diets (FO and CF) than those fed CP diet. Fish oil feeding significantly decreased th activities of lipogenic enzyme. Rats fed fish oil containing diets (FO, CF) exhibited the lower fatty acid synthase (FAS) activity than those fed CP diet and FAS activity was positively correlated with areas of GSP-P positivie foci. Glucose-6-phophate dehydrogenase activity was the lowest and peroxisomal ${\beta}$-oxidation was stimulated in rats fed FO diet compared to other groups. It was also found that serum cholesterol was decreased in FO group. Therefore, the preventive effect against hepatocarcinogenesis and hypolipidemic effect of fish oil can be explained partly by suppression of the hepatic lipogenesis and by increase of peroxisomal ${\beta}$-oxidation.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.2
• /
• pp.278-286
• /
• 2015

The overall purpose of this study was to investigate the effects of Chunggukjang and Greentea-Chunggukjang on the lipid profile, lipid peroxidation and antioxidative enzyme activities of liver tissue in growing male rats fed cholesterol. Twenty seven rats were divided into three treatment groups (Control, Chunggukjang and Greentea-Chunggukjang) and were given experimental diets with 1% cholesterol for 9 weeks. All rats in this study were fed a casein-based diet. Chunggukjang groups were fed diet containing 33.1% Chunggukjang powder. The Chunggukjang and Greentea-Chunggukjang groups showed significantly lower weight gain, food efficiency ratio than the control group regardless of Chunggukjang type. Serum total cholesterol was significantly lower in the Chunggukjang group than in the control group, whereas serum triglyceride and atherogenic index were significantly lower in the Greentea-Chunggukjang group than in the control group. Hepatic triglyceride contents was not significantly different among the diets. However, hepatic cholesterol content was significantly lower in the Greentea-Chunggukjang group than in the control group. Lipid peroxidation of malondialdehyde (MDA) contents was significantly lower in the Chunggukjang and Greentea-Chunggukjang groups than in the control group. Activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) in liver tissue of the Chunggukjang and Greentea-Chunggukjang groups were not significantly different. It can be concluded that Chunggukjang and Greentea-Chunggukjang influence lipid profile and hepatic malondialdehyde contents in growing male rats fed cholesterol.

• Korean Journal of Environmental Biology
• /
• v.24 no.2 s.62
• /
• pp.195-200
• /
• 2006

The response of hepatic mixed function oxygenase (MFO) system was investigated in olive flounder exposed to formalin. Hepatic microsome of olive flounder incubated in vitro with formalin demonstrated the induction of cytochrome P450 (CYP), ethoxyresorufin deethylase (EROD), cytochrome P450 reductase (P450R) and cytochrome b5 reductase (b5R) activity. In addition, olive flounder was exposed to 100, 300 and 500 ppm of formalin for 1 h and then transferred to a flow-through type of 1000 L aquarium. Hepatic MFO enzyme activity was determined for 72 h. As the result, hepatic CYP, P450R and EROD activities increased following exposure of formalin, but b5R and GST showed no significant change. These results imply that CYP and P450R can be considered as main hepatic enzymes involving in detoxification of formalin.

• BMB Reports
• /
• v.28 no.6
• /
• pp.490-493
• /
• 1995

We investigated the effect of hydrogen peroxide-treated metallothionein on the hepatic xanthine oxidase activity in vitro. When the metallothionein was preincubated with 1 mM of hydrogen peroxide, the activity of xanthine oxidase and type conversion were elevated dose-dependently by the addition of metallothionein into the reaction mixture. While increasing the treatment of hydrogen peroxide to the $50{\mu}g$of metallothionein, the xanthine oxidase activity and type conversion ratio were remarkably elevated dose dependently compared to the control. When cadmium ion was added to the reaction mixture, the increasing pattern of the enzyme activity was similar to the effect of hydrogen peroxide-treated metallothionein. DTT or penicillamine restored the increasing activity and type conversion of xanthine oxidase by the cadmium ion to the control level.

• Journal of Ginseng Research
• /
• v.27 no.1
• /
• pp.1-10
• /
• 2003

In present study, we examined whether or not the pretreatment of Korean Red Ginseng (KRG) could protect hepatotoxicity induced by carbon tetrachloride (CCl$_4$) and D-galatosamine (GalN). For this study, we not only tested activity of various plasma enzymes (AST, ALT, SDH, LDH), which are used as indicators of liver disease, but also checked the change of liver components such as lipid, glutathione and cytochromes content, and several liver enzyme activity. Pretreatment of KRG for two weeks significantly reduced the elevated plasma enzyme activities induced by CCl$_4$ and GalN. Pretreatment of KRG also restored the hepatic enzymes, malonedialdehyde formation, and depletion of reduced glutathione content induced by CCl$_4$ and GalN to near normal level. However, ${\gamma}$-glutamylcysteine synthetase activity was lot affected by KRG. These results suggest that KRG shows the hepatoprotective effect by reducing lipid peroxidation, by reducing the activity of free radical generating enzymes, and by preserving the hepatic glutathione.