• 한국식품영양과학회지
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• 제20권3호
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• pp.209-213
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• 1991

Methanethiol을 흰쥐에 투여시 혈청중 alanine aminotransferase 활성이 대조군 보다 약 3배의 유의한 증가를 보였으며, 이때 간 및 혈청중 xanthine oxidase 활성은 감소되는 경향을 보였다. 또한 간효소맥과 methanethiol의 혼액을 $37^{\circ}C$에서 preincuabation 시킨후 in vitro에서 xanthine oxidase활성을 측정 하였을때 본 효소의 활성이 억제됨과 동시에 기절인 xanthine의 량을 변화 시켜가면서 관찰한 kinetic 실험에서도 대조 시험에 비하여 Km치가 높게 나타났다.

• 약학회지
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• 제39권5호
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• pp.521-527
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• 1995

This study was done to determine the effect of lead acetate on the activities of the hepatic cytosofic xanthine oxidase and aldehyde oxidase which were well known as oxygen free radical generating enzyme in vitro. Lead ion accelerated the formation of lipid peroxide and the increment of xanthine oxidase(type O) activity and the type conversion ratio from xanthine dehydrogenase to xanthine oxidase dose-dependently. But xanthine dehydrogenase(type D) activity was decreased. Aldehyde oxidase activity was not changed by lead ion. These data suggested that lead-induced cellular to)dcity may be concerned partially with xanthine oxidase mediated lipid peroxidation.

• 약학회지
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• 제38권2호
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• pp.211-217
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• 1994

Copper intoxication and disturbance of copper metabolism induced various oxygen-derived free radicals related damages. The effect of copper ion on xanthine oxidase activity and type conversion of the enzyme which is concerned to generation of reactive oxygen species, was investigated, It was observed that xanthine oxidase activity was increased by addition of copper ion in the reaction mixture in proportional to the concentration of the metal ion until $60\;{\mu}M$, while the enzyme activity was inhibited in higher concentration of copper treatment. On the other hand, xanthine dehydrogenase activity was inhibited by copper ion addition with concentration dependently. Preincubation of enzyme source with $30\;{\mu}M$ of copper ion, which concentration marked increased the xanthine oxidase activity, unchanged the enzyme activity and type conversion compare to control in vitro system. It was also observed that copper induced xanthine oxidase activity and the enzyme type conversion was protected by dithiothreitol and penicillamine. These results indicate that the increment of the type conversion of xanthine oxidase necessarilly need the presence of copper ion in enzyme assay system.

• 동아시아식생활학회지
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• 제5권3호
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• pp.215-221
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• 1995

This study was undertaken to investigate the effect of Taraxacum herba extract on the hepatic xanthine oxidase activity as a oxygen free radical generating enzyme in vitro and in vivo. It was observed that partial purified hepatic xanthine oxidase (type O) activity was strongly inhibited by the addition of Taraxacum herba n-butanol extract in vitro. The Km value of xanthine oxidase without affecting the Vmax value for xanthine was significantly increased by the addition of ta-dase (type O) activity was significantly inhibited by the treatment of Taraxacum gerba n-butanol ex-tract for 5days(over 40mg/kg, i.p), whereas, xanthine oxidase (type D) activity was not changed by the injection of Taracacum herba n-butanol extract. Meanwhile, liver weight / body weight(%), serum alanine aminotransferase activity and hepatic lipid peroxide content in Taraxacum herba n-buta-nol extract-treated rat were not changed. These findings led us to conclude that Taraxacum herba n-butanol extract may regulate the hepatic xanthine oxidase type O activity to prevent toxic effect of oxidative stress by the oxygen free radicals.

• 한국식품영양과학회지
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• 제20권6호
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• pp.527-537
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• 1991

To evaluate an effect of liver xanthine oxidase on the induction of liver damage, carbon tetrachloride (CCl4) was intraperitoneally injected twice at 0.1ml/100g body weight to the rate fed a low (LP)or high protein diet(HP) while the control group fed LP or HP received only olive oil. The changing rate of liver xanthine oxidas activity was compared with that of a free radical generating enzyme, liver aniline hydroxylase and a scavenging enzyme, glutathions S-transferase activity between the rate fed a LP and those fed HP, and the two groups treated with CCl4. Concomitantly, the degree of liver damage which could be considered as the paramete for CCl4 metabolism in case of CCl4-intoxicated animal was observed in the present experimental conditions and the effect of allopurinol, xanthine oxidase inhibitor, on the CCl4-toxicity of rate liver was alos demostrated. On the other hand, the comparative effect of actinomycin D on the liver and serum xanthine oxidase of CCl4-treated rats fed HP with that of those fed LP and the kinetics of purifed liver enzyme from the liver of CCl4-treated rats fed HP was also compared with that of those fed LP to clarify the differences of xanthine oxidase activity between two groups. The increasing rate of liver weigth/body wt, serum levels of ALT and the decreasing rate of hepatic ALT activity and protein contents to each control group were higher in CCl4-treated rats fed HP than those fed LP. Under the animal models as indentified by the present data herein, the liver xanthine oxidase activity was higher in CCl4-treated rats fed HP than those fed LP, and the control group fed HP also showed the much higher activity xanthine oxidase than that fed LP, whereas there were no differences in the activity of hepatic aniline hydroxylase and glutathions S-transferase between the two group treated with CCl4. Although the hepatic aniline hydroxylase activity was somewhat higher in the rats fed HP than those fed LP, the increasing rate of liver xanthine oxidase to the rats fed LP was higher in those fed HP than that of liver aniline hydroxylase. The degree of liver damage identified such as liver weight and serum ALT activity was less in the CCl4-treated rats pretreated with allopurinol. These results suggest that even a system at which xanthine oxidase acts as well as the drug metabolizing enzyme may influence the acelatin of CCl4 metabolism. In addition, the purified liver xanthine oxidase from CCl4-treated rats fed HP showed decreased Km value when compared to its control group. The Km value of liver xanthine oxidase of CCl4-treated rats fed LP showed a similar Km value with its control group. Furthermore, the decreasing rate of liver and serum xanthine oxidase acitivity in CCl4-treated rats pretreated with actinomycin D to the CCl4-treated rats was higher in rats fed HP than in those fed LP. These results suggest that the inductino of xanthine oxidase in CCl4-treated rats fed HP may be greater than in those fed LP.

• 한국식품영양과학회지
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• 제22권4호
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• pp.418-422
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• 1993

기능성 식품과 생약재료의 이용을 위한 연구의 일환으로 한국산 녹차로부터 탄닌을 분리하여 xanthine oxidase 저해효과를 측정하였다. 녹차의 acetone 추출물에서 xanthine oxidase 저해효과가 있음이 확인되었고 정제된 탄닌의 효소 저해효과를 검토한 결과 xanthine oxidase 저해의 경우 galloyl tannin류가 nonga-lloyl tannin류보다 활성이 더 우수하였고 구조적 이성체에서도 (+)-catechin류 보다 (-)-epicatechin류가 효소저해 효과가 더 좋았으며, 각 물질간 상승 효과가 인정되었다. 녹차에서의 탄닌류는 xanthine oxidase에 대해 비경쟁적 저해를 하는 것을 알 수 있었다.

• Journal of Applied Biological Chemistry
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• 제62권3호
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• pp.275-280
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• 2019

약용식물 67종의 생리활성 부위를 대상으로 열수 추출물이 in vitro에서 xanthine oxidase의 활성에 미치는 효과를 확인하였다. 약용식물 중에서 황금, 지각, 하수오, 갈근, 청피, 복분자, 녹차 및 지실 추출물은 xanthine oxidase의 활성을 강력하게 저해하여 항통풍 천연소재로서의 활용 가능성이 높게 나타났다. 하수오 뿌리 추출물은 열과 pH에 대한 안정성이 우수하였고, 농도에 비례하여 xanthine oxidase의 활성을 저해하였다. 하수오 추출물은 2.0 mg/0.1 mL의 농도에서 xanthine oxidase에 대해 73.8%의 저해 효과를 나타내었다.

• BMB Reports
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• 제28권6호
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• pp.490-493
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• 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.

• Archives of Pharmacal Research
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• 제18권1호
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• pp.56-59
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• 1995

The effect of ceruloplasmin or copper ion on hepatic xanthine oxidase activity and type conversion was investigated using rat liver in vitro. It was observed that ceruloplasmin increased xanthine oxidase type conversion depending on duration of its storage. Xanthine oxidase (type O) activity and type conversion in incubation mixture was increased by the addition of heated celuroplasmin in a temperature dependent manner. The type conversioin of xanthine oxidase induced by heated ceruloplasmin was retumed to normal by the tratment with DTT or penicillamine. The effect of copper ion on type conversion of xanthine oxidase was similar to that of heated ceruloplasmin.

• 한국식품영양학회지
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• 제14권2호
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• pp.120-125
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• 2001

시중에서 흔하게 구할 수 있고 즐겨 마시는 차로 이용이 되고 있는 감잎을 시료로 택하여 메탄올로 추출한 후 헥산, 클로로포름, 에틸아세테이트, 부탄올, 물 등으로 각각 분획하여 xanthine oxidase에 대한 저해 효과를 살펴보았다. 메탄올 추출물에서는 시료 2.0mg/ml 첨가 시 78%의 높은 저해효과를 나타내었으며 농도가 증가할수록 저해효과가 우수한 것으로 나타났다. 또한 메탄올 추출물을 농도별로 첨가하여 반응시간에 따른 저해효과를 살펴본 결과 반응시간 1분에 가장 급속한 저해효과를 나타내었으며 시간이 증가할수록 효소 저해율의 증가는 완만하였다. 한편 각 용매별 획분에서도 마찬가지로 농도가 증가할수록 xanthine oxidase에 대한 저해효과가 증가하였으며 특히 에틸아세테이트 획분에서는 2.0mg/ml 첨가시 87%의 높은 저해율을 나타내어 xanthine oxidase에 대해 저해 효과가 가장 뛰어남을 알 수 있었다. 각 용매별 획분에 대하여 반응 시간별로 잔존하는 xanthine oxidase의 활성도는 에틸아세테이트 획분과 헥산 획분에서 가장 낮은 반면 물 획분에서 가장 높았으며, 각 획분 모두 반응시간 1분 안에 xanthine oxidase의 활성도가 급격히 감소되었고 그 이후 시간이 경과함에 따라서는 다소 완만한 감소를 나타내었다.