• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.202-206
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• 1983

After examining the changes of LDH activity in the liver, brain and kidney of albino rats administrated with various amounts and periods, the following results were obtained: The LDH activity in liver, brain and kidney showed a gradual increase in proportion to the amount of PCB. The LDH activity has considerably increased with PCB administration, the maximum increasing rate shown within the first five days and the second five days respectively for 50 & 100 ppm group and for 10 ppm group. The LDH activity of brain in 50 and 100 ppm group showed its peak increase for the first five days with its subsequent decrease, while there was almost no change until the 1th day in 10 ppm group. The LDH activity in kidney showed the greatest increase between the 10th and 15th day.

• Toxicological Research
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• v.12 no.2
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• pp.155-161
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• 1996

The enzymatic properties for NADPH-P450 reductase domain of a fusion protein between human cytochrome P450 1A1 and rat NADPH-P450 reductase expressed in Escherichia coli were investigated. The fusion plasmid pCW/1A1OR-expressed E. coli membrane showed high NADPH-cytochrome c reductase activity ($830.1\pm 85.8 nmol\cdot min^{-1}\cdot mg protein^{-1}$), while pCW control vector and P 450 1A1 expression vector pCW/1A1 showed relatively quite low activity ($4.35\pm 0.49, 3.27\pm 0.50 nmol\cdot min^{-1}\cdot mg protein^{-1}$, respectively). The kinetic curves for NADPH-cytochrome c reductase followed typical Michaelis-Menten kinetics. The $K_{max}$ and $V_{max}$ for NADPH-dependent reductase activity were $8.24\pm 2.61\mu $and $817.9\pm 60.8 nmol\cdot min^{-1}\cdot mg protein^{-1}$, respectively, whereas those for cytochrome c-dependent reductase activity were $19.97\pm 2.86\mu M$ and $1303.5\pm 67.1 nmol\cdot min^{-1}\cdot mg protein^{-1}$. The reductase activities were also compared with those of rat, porcine and human liver microsomes. The activity of pCW/ 1A1OR-expressed E. coli membrane was 15.2-fold higher than that of rat liver microsome. Treatment with benzo(a)pyrene, 7-ethoxyresorufin and $\alpha$-naphthofiavone which are known as specific substrates or inhibitor for human P450 1A1 increased NADPH-cytochrome c reductase activity of fusion protein in E. coli membrane dose-dependently. These results demonstrate that the membrane topology of fused enzyme may be important for activity of its NADPH-P450 reductase domain.

• Plant Resources
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• v.4 no.3
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• pp.196-199
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• 2001

Medicinal plants were screened for the inhibitory effects on human immunodeficiency virus type 1 pretense. Of the extracts tested, the strong inhibitory effects were observed in the acetone extracts of the pericarp of Camellia japonica. Camelliatannin H from the pericarp of C. japonica showed a potent inhibitory activity on HIV-1 pretense. Effects of the extract and compound from leaves of Zanthoxylum piperitum on the enzyme activities were investigated in the liver of bromobenzene-treated rats. The methanol extract and protocatechuic acid isolated from Z. pipetitum reduced the activity of aniline hydroxylase that increased by bromobenzene, while did not affect the activities of aminopyrin N-demethylase and glutathione S-transferase. The extract and protocatechuic acid recovered significantly the activity of epoxide hydrolase decreased by bromobenzene.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2001.11a
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• pp.68-73
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• 2001

Medicinal plants were screened for the inhibitory effects on human immunodeficiency virus type 1 pretense Of the extracts tested, the strong inhibitory effects were observed in the acetone extracts of the pericarp of Camellia japonica. Camelliatannin H from the pericarp of C. japonica showed a potent inhibitory activity on HIV- 1 pretense. Effects of the extract and compound from leaves of Zanthoxylum piperitum on the enzyme activities were investigated in the liver of bromobenzene-treated rats. The methanol extract and protocatechuic acid isolated from Z. piperitum reduced the activity of aniline hydroxylase that increased by bromobenzene, while did not affect the activities of aminopyrin N-demethylase and glutathione S-transferase The extract and protocatechuic acid recovered significantly the activity of epoxide hydrolase decreased by bromobenzene.

• Journal of Ginseng Research
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• v.20 no.2
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• pp.173-178
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• 1996

Aerobic cells are normally protected from the damage of free radicals by antioxidative on , zymes such as superoxide dismutase (SOD), catalase, glutathione (GSH) peroxidase, GSH S- transferase and GSH reductase which scavenge free radicals as well as nonenzymatic antioxidants such as ceruloplasmin, albumin and nonprotein-SH including GSH. The effects of each component (ginsenoside $Rb_1$, $Rb_2$, Rc, Rd, Re, $Rb_1$, Rf, $Rh_1$ and $Rh_2$) of red ginseng on the antioxidative enzyme activities were investigated in the liver in order to screen antioxidative components of red ginseng. Ginsenoside $Rb_1$ and Rc showed a tendency to increase GSH peroxidase activity, while ginsenoside Rc significantly decreased Cu,Zn-SOD activity. Especially, ginsenoside $Rh_2$ significantly increased catalase activity. These results suggest that ginsenoside $Rh_2$ is an important active component among total saponins of red ginseng.

• Journal of Life Science
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• v.11 no.1
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• pp.57-64
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• 2001

The cDNA encoding human NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc GalNac ${\alpha}$2,6-Sialyltransferase (hST6GalNac IV) was isolated by screening of human fetal liver cDNA library with a DNA probe generated from the cDNA sequence of mouse ST6Gal NAc IV (mkST6GalNAc IV). The cDNA sequence included an open reading frame coding for 302 amino acids, and comparative analysis of this cDNA with mST6GalNAc IV showed that each sequence of the predicted coding region contains 88% and 85% identifies in nucleotide and amino acid levels, respecively. The primary structure of this enzyme suggested a putative domain structure, like that in other glycosyltransferases, consisting of a short N-terminal cytoplamic domain, a transmembrane domain and a large C-terminal active domain. This enzyme expressed in COS-7 cells echibited transferase activity toward NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc, fetuin and GM1b, although the activity toward the later is very low, no significant activity being detected toward Gal${\beta}$ 1,3Gal NAc or asialofetuin, the other glycoprotein substrates tested. The $^{14}$ C-sialylated residue of fetuin sialylated by this enzyem with CMP-[$^{14}$C]NeuAc was sensitive to treatment with ${\alpha}$2,8-specific sialidase of Vibrio cholerae but resistant to treatment with ${\alpha}$2,3-specific sialidase (NaNase I), and ${\alpha}$2,3- and ${\alpha}$2,8-specific sialidase of Newcastle disease virus. These results clearly indicated that the expressed enzyme is a type of GalNAc ${\alpha}$2,6-sialyltransferase like mST6GalNAc IV, which requires sialic acid residues linked to Gal${\beta}$1,3GalNAc-residues for its activity.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1110-1114
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• 2008

$\beta$-Glucuronidases of intestinal bacteria are capable of retoxifying compounds that have been detoxified by liver glucuronidation, which is one of the most important detoxication processes in the liver. Therefore, this enzyme is known to accelerate colon cancer invasion and metastasis. Two bromophenols, 2,4,6-tribromophenol (I) and 2,4-dibromophenol (II), were purified from the red alga Grateloupia elliptica. $IC_{50}$ values of bromophenol I and II against Escherichia coli $\beta$-glucuronidase were 5.4 and 8.5 mg/mL, respectively. Hence, bromophenols of G. elliptica, a potent $\beta$-glucuronidase inhibitor, can be used as a novel pharmaceutical agent for the prevention and treatment of colon cancer.

• Journal of Nutrition and Health
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• v.34 no.5
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• pp.493-498
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• 2001

To investigate the effects of Ixeris sonchifolia Hance diets on serum and hepatic lipid levles and enzyme activities in rats administered with ethanol chronically, Sprague-Dawley male rats were AIN-76 diet(control), control diet plus ethanol, control plus Ixeris sonchifolia Hance diet, or control plus Ixeris sonchifolia Hance diet plus ethanol for 30 days. Ixeris sonchifolia Hance diets significantly decreased the serum total cholesterol, triglyceride, LDL-cholesterol, and GOT levels that were increased due to the chronic ethanol administration. In addition, Ixeris sonchifolia Hance diets significantly decreased the liver triglyceride and total lipid levels that were increased due to the ethanol administration. The present findings, combined with previous data showing differences in the effects of cabbage diets having a high or a low level of GABA on the lipid levels and the serum Y-GPT activity of rats(Cha and OH[2000] J. Korean Soc. Food Sci. Nutr. 29, 500-505) raise the possibility that GABA in plants could have a nytraceutical role in the recovery of chronic alcohol-related diseases. (Korean J Nutrition 34(5) : 493∼498, 2001)

• Journal of Pharmaceutical Investigation
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• v.41 no.3
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• pp.143-146
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• 2011

Scutellariae Radix is widely used in the traditional herbal medicine for the treatment of fever, cough, dysentery, hepatitis and hypertension in Korea, China and Japan. In this study, we investigated the effects of 70% ethanolic extract of Scutellariae Radix (SRE) on CYP450-mediated drug metabolism in the in vitro systems using human liver microsomes and hepatocytes. The microsomal incubation assay showed that SRE inhibited the drug metabolism reactions catalyzed by CYP1A2, CYP2C8 and CYP2C9 in a dose-dependent manner. In particular, SRE was shown to strongly inhibit the metabolic activity of CYP1A2 with an $IC_{50}$ value of 4.6 ${\mu}g/mL$. When SRE was evaluated for its effect on the induction of CYP450 enzyme activities in cryopreserved human hepatocytes, SRE did not exhibit any effect.

• YAKHAK HOEJI
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• v.49 no.4
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• pp.340-346
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• 2005

To investigate the effect of Feelch on alcohol metabolism, we measured both blood alcohol concentration in human and hepatic alcohol metabolizing enzyme activity in rats. The blood alcohol concentration in Feelch-ingested group was significantly lower than that in water-ingested group at 0, 40, and 80 minute after alcohol intake. The blood alcohol concentration between male and female taken 300ml of $21\%$ alcohol showed the significant differences; the peak value of blood alcohol concentration in male and female were $0.083\pm0.014\%\;and\;0.108\pm0.018\%$, respectively. In alcohol-fed rats, aldehyde dehydrogenase (ALDH) activity was significantly increased, whereas alcohol dehydrogenase (ADH) activity was not changed. In both Feelch-fed group and Feelch plus alcohol-fed group, ADH and ALDH activity were significantly increased as compared with each control group. Feelch decreased phospholipase $A_2$ activity and lipid peroxidation in hepatic tissue and activities of serum aminotransferases as compared with control. These results suggest that Feelch may have a hepatoprotective effects and this is likely due to lower blood alcohol concentration via the increment of hepatic ADH and ALDH activity.