枣多糖不同提取工艺优化及其免疫活性初探

Optimization of Different Extraction Processes of Jujube Polysaccharides and Comparison of Their Immunological Activities

摘要: 为探究不同提取工艺对枣多糖提取效果及生物活性的影响，采用热水浸提法、超声冰浴提取法以及酶解提取法提取枣多糖，优化出各自最佳提取工艺，并比较三种提取方法提取的枣多糖的免疫活性。结果表明：热水浸提法的最优提取条件为：液料比25:1 (mL/g)，提取温度90℃，提取时间2 h，此时枣多糖的提取率为54.27% ± 2.64%；超声冰浴提取法的最优工艺为：液料比25:1 (mL/g)，超声功率300 W，超声时间20 min，在最优提取条件下枣多糖提取率为56.93% ± 2.79%；酶解法的最优提取工艺为：0.5%混合酶(果胶酶:木瓜蛋白酶 = 1:1)，酶解时间2 h，酶解温度40℃，液料比25:1 (mL/g)，pH 4.0，此时枣多糖的提取率为55.22% ± 2.54%。对比三种不同方法可知，超声法得到的多糖提取率最高。另外，MTT以及促进免疫因子释放实验表明，三种工艺均对RAW264.7巨噬细胞有一定的毒性，但促进细胞的免疫因子释放，其中热水浸提法提取的多糖免疫活性最强。

Abstract: In order to explore the effects of different extraction processes on the extraction and bioactivity of jujube polysaccharides, jujube polysaccharides were extracted by hot water extraction, ultrasonic ice bath extraction and enzymatic extraction, and the best extraction techniques were optimized. We performed different extraction methods for the analysis of immunological activity. The results showed that the optimum extraction conditions for hot water extraction were as follows: liquid to solid ratio of 25:1 (mL/g), extraction temperature of 90˚C, extraction time of 2 h, at which time the extraction rate of jujube polysaccharide was 54.27% ± 2.64%. The optimal process of ice bath extraction method is: liquid to material ratio 25:1 (mL/g), ultrasonic power 300 W, ultrasonic time 20 min; under the optimal extraction conditions, the extraction rate of jujube polysaccharide is 56.93 ± 2.79%; the best enzyme extraction process is: 0.5% mixed enzyme (pectinase:papain = 1:1), enzymatic hydrolysis time 2 h, enzymatic hydrolysis temperature 40˚C, liquid to material ratio 25:1 (mL/g), pH 4.0; at this time, the extraction rate of jujube polysaccharide was 55.22% ± 2.54%. Comparing the three different methods, the extraction rate of polysaccharide obtained by ultrasonic method is the highest. In addition, MTT and immune factor release experiments showed that all the three processes were toxic to RAW264.7 macrophages, but promoted the release of immune factors. The polysaccharide extracted by hot water extraction method had the strongest immunological activity.