天冬多糖的复合酶提取工艺优化及其理化性质、吸湿性和抗氧化活性

Optimization of Compound Enzyme Extraction Process of Asparagus cochinchinensis Polysaccharides: Physicochemical Properties, Hygroscopicity, and Antioxidant Activity

摘要:

采用响应面法优化天冬粗多糖的复合酶提取工艺，考察提取时间、提取温度、酶底质量比和缓冲液pH值对天冬粗多糖得率的影响，并对最优条件下获得的天冬粗多糖的理化指标、抗氧化活性和吸湿性进行鉴定。结果表明，复合酶法提取天冬粗多糖的最佳工艺条件为提取时间4.5 h，提取温度42.0 ℃，酶底质量比1.5%，缓冲液pH值5.3，粗多糖得率为18.54%。天冬粗多糖中糖纯度高达95.49%，蛋白质和多酚含量分别为1.07%和0.11%。单糖组成结果表明，天冬粗多糖主要由葡萄糖、果糖、岩藻糖、半乳糖和木糖组成，摩尔比为53.91:26.00:6.19:5.33:4.53，且具有双螺旋结构。吸湿性实验结果表明，天冬粗多糖的吸湿率，与甘油的吸湿率相似，远高于透明质酸钠的吸湿率；抗氧化实验结果表明，天冬粗多糖具有良好的抗氧化活性。该研究为复合酶法提取并获得新型的高纯度、高活性的天冬粗多糖开发利用提供了理论基础和应用价值。

Abstract:

Response surface methodology was used to optimize the compound enzyme extraction process of Asparagus cochinchinensis crude polysaccharides. The effects of extraction time, temperature, enzyme to substrate mass ratio, and buffer pH on the yield of A. cochinchinensis crude polysaccharides were investigated. Physicochemical indices, antioxidant activity, and hygroscopicity of A. cochinchinensis crude polysaccharides obtained under the optimal conditions were identified. The optimal conditions for compound enzymatic extraction of A. cochinchinensis crude polysaccharides were an extraction time was 4.5 h, extraction temperature of 42.0 ℃, enzyme to substrate mass ratio of 1.5%, and buffer pH of 5.3. The optimized yield of crude polysaccharides was 18.5%, sugar purity of A. cochinchinensis crude polysaccharides reached 95.49%, and protein and polyphenol contents were 1.07% and 0.11%, respectively. Monosaccharide composition analysis revealed that A. cochinchinensis crude polysaccharides mainly consisted of glucose, fructose, fucose, galactose, and xylose in a respective molarratio of 53.91:26.00:6.19:5.33:4.53, and a double helix structure. Hygroscopic analysis revealed a similar moisture absorption rate of A. cochinchinensis crude polysaccharides to that of glycerol, but a markedly higher rate than that of sodium hyaluronate. A. cochinchinensis crude polysaccharides displayed good antioxidant activity. The findings provide a theoretical basis for the enzyme-assisted extraction of highly pure and active A. cochinchinensis crude polysaccharides, which may have valuable potential applications.