响应面法优化多聚原飞燕草素超声波降解工艺及其抗氧化性的研究

姜坤; 叶焕烽; 叶秦轩; 杨海花

doi:10.13386/j.issn1002-0306.2020100222

响应面法优化多聚原飞燕草素超声波降解工艺及其抗氧化性的研究

Optimization Technology of Ultrasonic Degradation of Polymeric Prodelphinidin by Response Surface Methodology and Its Antioxidant Activity

摘要

摘要: 研究从杨梅叶中提取制备多聚原飞燕草素，并采用HPLC-DAD-ESIMS等方法对其结构进行了表征。利用单因素实验分析了超声时间、温度等超声波处理条件对多聚体的降解规律。在此基础之上，通过Box-Behnken响应面试验研究了超声波降解多聚原飞燕草素的条件，并采用DPPH·法和ABTS·⁺法比较了降解前后的抗氧化活性。结果表明制备的多聚原飞燕草素提取率为5.96%，平均聚合度为27.8，其结构组成主要为EGCG。超声波处理不同条件均对多聚体的降解有影响作用，其中主要影响因素为时间、温度、功率与占空比（P<0.05）。通过Box-Behnken响应面试验确定的最优降解条件为超声时间74 min，温度44 ℃，超声功率361 W，脉冲占空比67%，对应小分子的低聚原花色素得率为17.31%。超声波处理后多聚原飞燕草素相比处理前抗氧化活性显著提高（P<0.01）。

Abstract: In this research, polymeric prodelphinidins (PPs) were extracted and prepared from bayberry leaves and characterized using HPLC-DAD-ESIMS. Then effects of ultrasonic time, temperature, power and duty cycle on PPs were analyzed using one single factor test. On the above bases, the response surface methodology with Box-Behnken design was employed to study the ultrasonic conditions. Furthermore, the antioxidant capacity of PPs were determined before and after ultrasonic treatment by DPPH· and ABTS·⁺ methods. The results showed that yield of PPs from bayberry leaves was 5.96% (dry weight) with an average degree of polymerization of 27.8 and with a main structural component of EGCG. Ultrasonic treatments with different conditions had different influence on PPs degradation. Factors of ultrasonic time, temperature, power and duty cycle had significant effects (P<0.05). The optimized ultrasonic conditions were as follows: Ultrasonic time 74 min, temperature 44 ℃, ultrasonic power 361 W, and duty cycle 67%. Under these conditions, the yield of oligomeric prodelphinidins was 17.31%. After sonication, PPs possessed more significant antioxidant capacity than before (P<0.01).