超声波辅助酶法制备壳寡糖及抗氧化活性研究

Study on preparation of chitosan oligosaccharide by ultrasonic-enzyme synergistic method and its antioxidant activity

壳寡糖是壳聚糖降解后的产物,其与壳聚糖相比分子量更小,水溶性更好,生物利用度更高的特点。本实验拟采用超声波辅助果胶酶处理壳聚糖制备壳寡糖,通过正交试验优化制备工艺。结果表明,最佳工艺条件为:酶浓度1600 U/g,酶解温度50℃,反应时间60 min,超声波功率120 W。在该条件下获得的降解产物中还原糖浓度为1.96 mg/mL,制备效果优于超声波和酶解分别降解的方法。对此法制备的壳寡糖的体外抗氧化活性进行研究,结果表明对DPPH自由基和羟自由基均有较强的清除能力。

Chitosan oligosaccharide is the degradation product of chitosan, which has small molecular weight, good water - soluble and a higher oavailability. In this experiment chitosan was degraded by pectinase under ultrasonic wave. The orthogonal experiments were conducted to obtain the optimal hydrolysis conditions, The results showed that the opti- mal technological condition was as follows： pectinase addition 1600 U/g, enzymolysis temperature 50 ℃, enzymolysis time under ultrasonic wave 60 min and ultrasonic power 120 W. In these conditions, the concentration of reducing sug- ar was determined to 1.96 mg/mL, and the effect was better than the preparation effect by ultrasonic method and enzymatic hydrolysis respectively. The antioxidative activities of chitosan oligosaccharideprepared by this method were studied. The results showed that chitosan oligosaceharidedemonstrated significant scavenging effects on DPPH and hydroxyl radical.