蜂胶不同溶剂萃取物组成和抗氧化性的研究

以蜂胶为原料，分别以甲醇、乙醇、氯仿、蒸馏水为溶剂进行萃取，测定各萃取物总酚与黄酮类物质的含量，通过测定还原能力，清除DPPH 自由基能力的测定来比较4 种不同萃取物的抗氧化性。结果表明：甲醇萃取物具有较强的抗氧化性。甲醇萃取物浓度为0.25mg/ml 时还原力高达1.162，且浓度为0.05mg/ml 时对DPPH 自由基清除率为64.676%。乙醇萃取物通过石油醚、氯仿、乙酸乙酯、丙酮依次分级萃取后所得到4 种萃取物各项指标测定结果表明，氯仿萃取了蜂胶乙醇萃取物中主要成分，但乙酸乙酯和丙酮萃取物的还原能力及清除DPPH 自由基清除能力较佳，在浓度为0.05mg/ml 时还原力分别为2.087 和1.798，DPPH自由基清除率达87.724% 和88.013%。

Chemical Compositions and Antioxidant Activity of Different Solvent Extracts from Propolis

Different solvents such as methanol, ethanol, chloroform and distilled water were used to extract propolis. The contents of total flavonoids and total phenols in different solvent extracts were analyzed. Meanwhile, reducing power and DPPH free radical scavenging capacity were determined to compare antioxidant activity of four different solvent extracts. Results indicated that methanol and ethanol extracts had strong antioxidant activity. The reducing power of methanol extract was as high as 1.162 at 0.25 mg/ml concentration of and scavenging rate of methanol extract for DPPH free radicals was 64.676% at 0.05 mg/ml concentration of. The sequential extractions using petroleum ether, chloroform, ethyl acetate and acetone were applied to ethanol extract of propolis. A maximum extraction efficiency was achieved using chloroform. The reducing power of chloroform-soluble extract reached 2.087 and the scavenging capacity for DPPH free radicals as high as 87.724% at 0.05 mg/ml concentration.