辣木叶提取物的制备及抗氧化活性

采用16种提取方法制备辣木叶提取物,考察不同提取方法对辣木叶蛋白、糖类、多酚类物质提取率和抗氧化剂溶出率的影响。采用乙酸乙酯萃取辣木叶提取物,研究水相中蛋白(水解蛋白)、糖类和乙酸乙酯相中多酚类物质相互作用对辣木叶提取物抗氧化活性的影响。结果表明:采用酶法以及酶法耦合乙醇提取法可以制备蛋白(水解蛋白)、糖类和多酚类物质含量高且抗氧化活性强的辣木叶提取物。采用Ns37071蛋白酶、胰酶时,所得辣木叶提取物蛋白、糖类、多酚类物质提取率最高,抗氧化活性最强。蛋白(水解蛋白)和糖类物质对辣木叶提取物抗氧化活性的贡献大于多酚类物质,是辣木叶提取物发挥抗氧化活性的重要物质基础。此外,辣木叶提取物中蛋白(水解蛋白)、糖类、多酚类物质存在协同增效或拮抗作用。

Preparation of Moringa oleifera Leaf Extracts and Their Antioxidant Activities

Active components were extracted from Moringa oleifera leaves using 16 different methods. The effects of different extraction methods on the yields of proteins, saccharides, phenolics and antioxidants were investigated. In the case of ethyl acetate extraction, the effect of the interaction among proteins (protein hydrolysates) and saccharides in the aqueous phase and phenolics in the ethyl acetate phase on the antioxidant activity of Moringa oleifera leaf extracts was evaluated. An extract with high contents of proteins, saccharides and phenolics and strong antioxidant activity was obtained by enzymatic extraction or enzyme-assisted ethanol extraction. Ns37071 protease and pancreatin, respectively gave the highest yield of proteins, saccharides and phenolics and strongest antioxidant activity. Proteins (protein hydrolysates) and saccharides made greater contribution to the antioxidant activity of Moringa oleifera leaf extract that did phenolics. Furthermore, there were synergistic or antagonistic effects among proteins, saccharides and phenolics in the extract.