黄秋葵粗多糖体外抗氧化活性测定

目的:测定黄秋葵粗多糖(RPS)的体外抗氧化活性.方法:采用水提醇沉淀法提取黄秋葵RPS,并用蒽酮-硫酸法测定RPS的含量,应用1,1-二苯基苦味酰基苯肼(DPPH)氧化法检测0.086、0.171、0.342、0.684、1.367和2.734 g/L RPS对 DPPH自由基(DPPH·)的清除率,水杨酸法检测0.157、0.313、0.625、1.250、2.500和5.000 g/L RPS对羟基自由基(·OH)的清除率,邻苯三酚自氧化法检测0.086、0.171、0.342、0.684、1.367和2.734 g/L RPS对超氧阴离子自由基(O2÷)的清除率,以维生素C作阳性对照.结果:黄秋葵中RPS含量为(11.23±0.04)%.RPS对DPDH·、·OH和O2÷的体外清除率呈现剂量依赖性.2.734 g/L RPS对DPPH·和O2÷的清除率分别达(44.48±0.64)%及(35.67±0.21)%,5.000 g/L RPS对·OH的清除率达(68.63±0.07)%.其清除能力较维生素C稍弱.结论:黄秋葵RPS具有较明显的体外抗氧化能力.

Determination of antioxidant activity of okra raw polysaccharides in vitro

Aim:To study the antioxidant activity of okra raw polysaccharides(RPS) in vitro.Methods:RPS was extracted from fresh okra by hot water,then precipitated by alcohol,and its total sugar content was determined by the anthrone-sulfuric acid method.1,1-dipheny-2-picrylhy-drazyl(DPPH) oxidation method was adopted for measuring the DPPH free radicals(DPPH·) clearance of 0.086,0.171,0.342,0.684,1.367,2.734 g/L RPS,salicylic acid method was adopted for measuring hydroxyl radicals(·OH) clearance of 0.157,0.313,0.625,1.250,2.500,5.000 g/L RPS,pyrogallol autoxidation method was adopted for determining superoxide anion free radicals(O2÷) clearance of 0.086,0.171,0.342,0.684,1.367,2.734 g/L RPS.Vitamin C was selected as a positive control.Results:The content of RPS was(11.23±0.04)%.The scavenging effects of RPS had certain dosage-dependent trend and was lower than that of Vitamin C.When the concentration of RPS was 2.734 g/L,the clearance rates of DPPH·and O2÷ were(44.48±0.64)% and(35.67±0.21)%,respectively.The clearance rate of ·OH was(68.63±0.07)% when the concentration was 5.000 g/L.Conclusion:Okra RPS exhibit obvious antioxidant activity in vitro.