AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cer...AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant.展开更多
Polysaccharides of Tricholoma matsutake Sing. were extracted with boilingwater, followed by precipitating with ethanol. Two membranes of different molecular weight cut-off, namely, 30 kD and 10 kD were chosen with ult...Polysaccharides of Tricholoma matsutake Sing. were extracted with boilingwater, followed by precipitating with ethanol. Two membranes of different molecular weight cut-off, namely, 30 kD and 10 kD were chosen with ultrafiltration. The antioxidant activity of the purification polysaccharides was evaluated by various antioxidant assay, including DPPH （l,l-diphenyl-2-picrylhydrazyl） radical scavenging, superoxide anion radical scavenging and hydrogen peroxide scavenging. The scavenging effect on hydroxyl radical and DPPH radical, which may be comparable to Vitamin C, while the scavenging effect on superoxide anion radicals was not obvious.展开更多
Lagenaria siceraria （Molina） Standl., known as bottle gourd is widely available throughout Vietnam as an edible vegetable. Bottle gourd is a commonly fruit but there are little reports about its biological activitie...Lagenaria siceraria （Molina） Standl., known as bottle gourd is widely available throughout Vietnam as an edible vegetable. Bottle gourd is a commonly fruit but there are little reports about its biological activities. The aim of the present study was to evaluate antioxidant activity and anti-hyperglycemic potential of ethanolic extract of bottle gourd. The ethanolic extract was tested for its antioxidant activity on chelating power, the ferric reducing/antioxidant power assay （FRAP） and the 1, 1-diphenyl-2-picryl-hydrazyl （DPPH） free radical scavenging assay. The results showed that chelating activity was 80.02%, FRAP value was 92.84 μmol Fe^2＋/g and active radical scavenging which showed an IC50 was 49.50 μg/ml. The five different doses of ethanolic extract were treated by oral tolerance to mice body before oral glucose tolerance and blood glucose level was measured using glucose oxidase method. The result indicated that inhibition percentage of ethanolic extract of bottle gourd at the dose of 400 mg/kg in glucose-induced hyperglycemic mice was effectively similar to standard drug glibenclamide. The results obtained indicate that ethanolic extract from bottle gourd is the potential antioxidant and anti-hyperglycemic agent.展开更多
文摘AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant.
文摘Polysaccharides of Tricholoma matsutake Sing. were extracted with boilingwater, followed by precipitating with ethanol. Two membranes of different molecular weight cut-off, namely, 30 kD and 10 kD were chosen with ultrafiltration. The antioxidant activity of the purification polysaccharides was evaluated by various antioxidant assay, including DPPH （l,l-diphenyl-2-picrylhydrazyl） radical scavenging, superoxide anion radical scavenging and hydrogen peroxide scavenging. The scavenging effect on hydroxyl radical and DPPH radical, which may be comparable to Vitamin C, while the scavenging effect on superoxide anion radicals was not obvious.
文摘Lagenaria siceraria （Molina） Standl., known as bottle gourd is widely available throughout Vietnam as an edible vegetable. Bottle gourd is a commonly fruit but there are little reports about its biological activities. The aim of the present study was to evaluate antioxidant activity and anti-hyperglycemic potential of ethanolic extract of bottle gourd. The ethanolic extract was tested for its antioxidant activity on chelating power, the ferric reducing/antioxidant power assay （FRAP） and the 1, 1-diphenyl-2-picryl-hydrazyl （DPPH） free radical scavenging assay. The results showed that chelating activity was 80.02%, FRAP value was 92.84 μmol Fe^2＋/g and active radical scavenging which showed an IC50 was 49.50 μg/ml. The five different doses of ethanolic extract were treated by oral tolerance to mice body before oral glucose tolerance and blood glucose level was measured using glucose oxidase method. The result indicated that inhibition percentage of ethanolic extract of bottle gourd at the dose of 400 mg/kg in glucose-induced hyperglycemic mice was effectively similar to standard drug glibenclamide. The results obtained indicate that ethanolic extract from bottle gourd is the potential antioxidant and anti-hyperglycemic agent.
