• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.259-264
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• 1999

To evaluate the bacterial reverse mutation of xylooligosaccharide(XO)s the in vitro Ames test using Salmonella typhimurium (TA9S, TAIOO, TA1535, TA1537) and Escherichia coli (WP2 uvrA) was performed. XO was negative in Ames test with Salmonella typhimurium and Escherichia coli with and without rat liver microsomal enzyme (S-9 fraction). According to the results, XO does not cause bacterial reverse mutation.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.203-209
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• 1994

When $^{14}C-{\alpha}-endosulfan$ was incubated with carp liver, kidney and gut preparations, it was metabolized to water soluble and organosoluble metabolites. In an in vitro test, endosulfan was converted to endosulfan ${\alpha}-hydroxyether$ (EHE), endosulfan alcohol (EA) and endosulfan ether (EE). The addition of NADPH resulted in rapid conversion of endosulfan to the metabolites in 105,000 g soluble fraction and microsomes. However, the rate of metabolism of endosulfan in liver, kidney and gut supplemented with NADPH as a cofactor was higher in the 105,000 g soluble fraction than that in the microsomes of carp under incubation conditions. The enzymes probably involved in the metabolism of endosulfan include the glutathione S-transferase (GST) and the mixed function oxidases (MFO), based on the evidence that addition of either GSH or NADPH increased the degradation of endosulfan.

• The Korean Journal of Pharmacology
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• v.16 no.2 s.27
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• pp.45-53
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• 1980

Lipid peroxidation in vitro has been identified as a basic deteriorative reaction in cellular mechanism of aging processes, such as air pollution oxidant damage to cell and to the lung, chlorinated hydrocarbon hepatotoxicity. Many experimental evidences were reported by several investigators that lipid peroxidation could be one of the principle causes for the hepatotoxicity produced by $CCl_4$. It is now reasonably established that $CCl_4$ is activated to a free radical in vivo, that lipid peroxidation occurs very quickly in microsomes prepared from damaged livers, that the peroxidation is associated with loss of enzyme activity of microsomes, and that various antioxidants can protect animals against the hepatotoxic effect of $CCl_4$. Recent studies have drawn attention to some other feature of microsomal lipid peroxidation. Incubation of liver microsomes in the presence of NADPH has led to a loss of cytochrome $P_{450}$. However, the presence of an antioxidant prevented lipid peroxidation and preserved cytochrome $P_{450}$. Decrease of cytochrome $P_{450}$ in microsomes under in vitro incubation can be enhanced by $CCl_4 and these changes were parallel to a loss of microsomal polyunsaturated fatty acid and formation of malonaldehyde. The primary purpose of this experiment was to study the effect of riboflavin tetrabutylate on lipid peroxidation, specially, the relationship between lipid peroxidation and drug metabolizing enzyme system which is located in smooth endoplasmic recticulum as well as the effect of ritoflavin tetrabutylate on drug metabolizing enzyme system of animal treated with $CCl_4$. Albino rats were used for experimental animal. In order to induce drug metabolizing enzyme system, phenobarbital was injected intraperitoneally. $CCl_$ and riboflavin tetrabutylate were given intraperitoneally as solution in olive oil. Microsomal fraction was isolated from liver of animals and TBA value as well as the activity of drug metabolizing enzyme were measured in the microsomal fractions. The results are summerized as following. 1) The secobarbital induced sleeping time of $CCl_4$ treated rat was about 2 times longer than that of the control group. However, the pretreatment with riboflavin tetrabutylate inhibited completely the lengthened sleeping time due to $CCl_4$ treatment. Furthermore TBA value was significantly increased in $CCl_4$ treated rat in comparison to control group tut the increase of TBA value was prevented by the pretreatment with riboflavin tetrabutylate. On the other hand, the activity of hepatic drug metabolizing enzyme was decreased in $CCl_4$ group, however, the pretreatment with riboflavin tetrabutylate also prevented the decrease of the enzyme activity caused by $CCl_4$. 2) The effect of riboflavin tetrabutylate on TBA value and the activity of drug metabolizing enzyme in vitro was similar to in vivo results. Incubation of liver microsome from rat in the presence of $CCl_4$, $Fe^{++}$, or ascorbic acid has led to the marked increase of TBA value, however, the addition of riboflavin tetrabutylate in incubation mixture prevented significantly the increase of TBA value, suggesting the inhibition of lipid peroxidation. In accordance with TBA value, the activity of drug metabolizing enzyme was inhibited in the presence of $CCl_4$, $Fe^{++}$, ascorbic acid but the addition of riboflavin tetrabutylate protected the loss of the enzyme activity in microsome under in vitro incubation.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.114-122
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• 1998

This study was designed to observe the effect of hot water soluble polysaccharides extract(PS) from Lentinus edodes on the enzyme activities related with hepatic function and peroxidation in the rats fed better yellow. The four groups of male SD rats were fed with the diets contained 15% casein(basal diet; NO group), added butter yellow(BO group) or /and PS(NP, BP group) for 6 weeks. The activities of ${\gamma}$-GTP and GPT in BP were significantly lower compared with BO. The activities of glutathione peroxidase, catalase and lactate dehydrogenase were not significantly different between NP and NO, while those activities were significantly lower value in BP than BO. The activities of glutathione S-transferase of the microsomal and cytosol fractions were significantly lower in BP than in BO. The contents of glutathione and malondialdehyde in the liver were considerably low value in BP. In a view of these results the PS of Lentinus edodes prevents the lipid peroxidation and diminishes the liver toxicity caused with better yellow. The superoxide dismutase activity in cytosolic fraction of liver was not found any effect in all groups. But hepatic function enzyme activities such as catalase and glutathione peroxidase, LDH activities were remarkably decreased in the groups 2(basal diet + PS) and the ${\gamma}$-GTP, GOT and GPT activities, too. In liver, the contents of glutathione decreased by PS supplementation but HDL-cholesterol and total cholesterol ratio in plasma decreased at the groups 3, 4. The ${\gamma}$-GTP, GOT and GPT in plasma were remarkably higher in the rats fed the p-DAB than the control group, too. But above enzyme activities significantly decreased in the groups fed PS.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.47-52
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• 1998

3-Hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes the conversion of HMG-CoA to mevalonic acid, the first intermediate of isoprenoid biosynthetic pathway in plants. The enzyme was solubilized with 0.4% Brij (polyoxyethylene ether) W-1 from a microsomal fraction of etiolated rice seedlings (Oryza sativa L.) in which its maximal activity was observed on the fourth day after germination. HMGR was purified to near homogeneity by employing $(NH_4)_2SO_4$ fractionation plus chromatographic procedures including DEAE-Sephadex A-50 and HMG-CoA-hexane-agarose affinity column. The size of the purified enzyme was estimated to be 55 kDa when judged by SDS-PAGE analysis with silver staining method. The apparent $K_m$ and $V_{max}$ values for HMG-CoA were determined to be $180\;{\mu}M$ and 107 pmol/min/mg, and those for NADPH were $810\;{\mu}M$ and 32.1 pmol/min/mg, respectively.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.112-116
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• 1997

The enzymatic properties as well as its distribution in the cerebral region and subcellular organells were investigated for the neurosteroid acyltransferase from the bovine brain, which synthesize the fatty acid esters of the neurosteroids. The cerebellum region was the highest in NSAT activity while the cerebrum was the lowest with 50% of the cerebellar activity. The NSAT was found to be mainly localized in the microsomal fraction. The optimal temperature and pH were $40^{\circ}C$ and 4.9, respectively. When $^3H-DHEA$ was utilized as substrate, the $K_m$ and $V_{max}$ was $32.6\;{\mu}M$ and 4.86 nmole/mg protein/h, respectively. Under the same condition pregnenolone$({\Delta}^5P)$ was a competitive inhibitor with $K_i=22.8\;{\mu}M$ and testosterone was a uncompetitive inhibitor with $K_i=22.8\;{\mu}M$. This may suggest that the NSAT has a different conformation in the acylation of the ${\beta}-hydroxyl$ group at C-3 and C-17.

• Journal of Food Hygiene and Safety
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• v.20 no.3
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• pp.175-178
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• 2005

Clean Natural is a new disinfectant of which main components are propolis and wood vinegar from Quercus mongolica. To evauate the bacterial reverse mutation of Clean Watural, the in vitro Ames test using Salmonella typhimurium TA98, TA100, TA102, TA1535 and TA1537 were performed with clean natural at the concentrations 0, 5, 2.5, and 1.25 mg/ml/plate. Clean Natural was negative in Ames test with Salmonella typhymuyium with and without rat liver microsomal enzyme (S-9 fraction). These results indicate that Clean Watural does not cause bacterial reverse mutation.

• Journal of the Korean Society of Tobacco Science
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• v.13 no.1
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• pp.19-26
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• 1991

Ames test using special strains which are histidine requiring mutant of Salmonella typhimufium , is widely utilized as short-term bioassay to evaluate the genotoxicity of chemicals. This method requires the liver microsome(5-9 fraction) to provide mammalian metabolism of the compounds, Therefore, the mutagenic potency of the chemicals is affected by not only the intrinsic properties of them but also the efficiency of the in vitro microsomal activation system. For this reason, the complex mixtures such as environmental pollutants from occupational sources, natural products or cigarette smoke condensates(CSC) , might be often appeared the false results. Induction of sister chromatid exchange(SCE) in cultured cells is known as another sensitive and powerful tool for the measurement of genotoxicity and the method has also an advantage which is able to apply to the in vitro and in vivo systems. In the present study, the inducibilities of revertant colonies in tester strain TA98 and SCE in human Iymphocytes by positive controls and total particulated materials(TPM) obtained from various brand(domastic and imported) cigarettes were compared in order to investigate whether the results in Ames test are in agreement with those in SCE analysis. The mutagenic activities of well known mutagens such as B(a)P showed excellent dose-response in the both methods although the induction mechanism was different each other, but cyclophosphamide resulted such effect only in SCE analysis. Most TPM tested showed a similar pattern in the mutagenic activities in those methods. However, only two(one imported brand and one domestic sample cigarettes) among the TMP obtained from various cigarettes appeared the higher induction in SCE than Ames test.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.601-609
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• 1998

The present study was undertaken to examine the role of phospholipase $A_2\;(PLA_2)$ in oxidant-induced inhibition of phosphate transport in primary cultured rabbit renal proximal tubule cells. Uptakes of phosphate and glucose were dose-dependently inhibited by an oxidant t-butylhydroperoxide (tBHP), and the significant inhibition appeared at 0.025 mM of tBHP, whereas tBHP-induced alterations in lipid peroxidation and cell viability were seen at 0.5 mM. tBHP stimulated arachidonic acid (AA) release in a dose-dependent fashion. A $PLA_2$ inhibitor mepacrine prevented tBHP-induced AA release, but it did not alter the inhibition of phosphate uptake and the decrease in cell viability induced by tBHP. tBHP-induced inhibition of phosphate transport was not affected by a PKC inhibitor, staurosporine. tBHP at 0.1 mM did not produce the inhibition of $Na^+-K^+-ATPase$ activity in microsomal fraction, although it significantly inhibited at 1.0 mM. These results suggest that tBHP can inhibit phosphate uptake through a mechanism independent of $PLA_2$ activation, irreversible cell injury, and lipid peroxidation in primary cultured rabbit renal proximal tubular cells.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.199-208
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• 2002

Objective : This study was undertaken to determine if Carthami Semen Aquacupunc- ture(CSA) exerts protective effect against alterations in membrane transport function rabbits with mercury chloride(HG)-induced acute renal failure. Methods : The administration of Hg at a subcutaneous single dose of 10 mg/kg caused a reduction in GFR and an increase in fractional Na excretion, indicating generation of acute renal failure. When CSA were given for 7 days prior to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased in rabbits treated with Hg alone. Results : The increase in rabbits treated with Hg following CSA are significantly lower than that in animals treated with Hg alone. Uptakes of glucose and phosphate in purified isolated brush-border membrane and Na-K-ATPase activity in microsomal fraction were inhibited in rabbits treated with Hg alone. Such changes were prevented by CSA. Uptakes of organic ions, PAH and TEA, in renal cortical slices were inhibited by the administration of Hg, which was prevented by CSA. Exposure of renal cortical slices to Hg in vitro caused an increased LDH release and lipid peroxidation, which was significantly prevented by CSA extract. Conclusions : These results indicate that the administration of Hg causes impairment in reabsorption of solutes in the proximal tubule via the generation of reactive oxygen species. CSA provides the protection against the impairment in proximal reabsorption, and its effect may be resulted from its antioxidant effect.