荔枝核提取物抗氧化活性及红外光谱特性

Antioxidant activities and infrared spectroscopic properties of extract from litchi seeds

以荔枝核为原料,以95%的乙醇为提取剂,在超声波的作用下得到荔枝核乙醇提取物。利用提取物对DPPH自由基和羟自由基的清除能力评价其抗氧化活性;同时测定了提取物的总还原能力和总的抗氧化性。最后通过红外光谱对提取物进行了定性分析。实验结果表明:荔枝核提取物具有很强的抗氧化活性,其抗氧化能力大于BHT,小于维生素C;荔枝核提取物清除DPPH·和·OH的IC50分别为0.032、0.160mg/mL。每克荔枝核提取物总抗氧化能力相当于210mgVc的总抗氧化能力;从红外光谱的结果可知,荔枝核提取物主要为黄酮类物质。

The dried samples of litchi seeds were cut into small pieces and soaked in 95% （v/v） ethanolic aqueous solution under the ultrasonic for some time. The extract was decanted,filtered under vacuum, concentrated in a rotary evaporator,and then lyophilized. The resulting extracts were employed for the current study. DPPH radical and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. Total reducing power and antioxidant capacity of the extract were determined at the same time. Qualitative analysis of the extract was studied by infrared spectroscopic. The experiment results showed that the extract could play an important role in the antioxidant activity. The order of antioxidant was Vc〉 extract〉BHT. The IC50 values of extract against DPPH radical and hydroxyl radical were 0.032mg/mL and 0.160mg/mL, respectively. Total antioxidant capacity of per gram extract was equal to 210mg Vc. Main component of the extract was flavonoid from infrared spectroscopic.