不同分子量茯苓多糖抑制酪氨酸酶活性及抗炎功效的研究

Study on Inhibition of Tyrosinase Activity and Anti-inflammatory Effect of Poria cocos Polysaccharides with Different Molecular Weights

通过超微粉碎茯苓粉,采用热水浸提法获得茯苓粗多糖,粗多糖醇沉后复溶,过截留相对分子质量为5k Da和10 k Da的超滤膜,再经醇沉,冷冻干燥获得不同分子量的茯苓多糖PW-P1、PW-P2和PW-P3。采用体外DPPH自由基清除、LPS诱导NO炎症及酪氨酸酶活性模型,测试其抗炎及美白活性。结果表明,茯苓多糖PW-P1、PW-P2、PW-P3的粗多糖含量分别为96.46%、93.18%、92.25%,且具有良好的清除DPPH自由基作用,其中多糖PW-P3对DPPH自由基的清除率IC50为0.45 mg·mL^(-1),而多糖PW-P1与PW-P2的IC50则大于0.8mg·mL^(-1)。茯苓多糖PW-P1、PW-P2、PW-P3在浓度为50μg·mL^(-1)~1 000μg·mL^(-1)的条件下,对脂多糖诱导的产生的NO有显著的抑制作用,其中多糖PW-P2、PW-P3对NO的抑制率大于多糖PW-P1。初步证实茯苓多糖PW-P1、PW-P2、PW-P3具有一定的抑制酪氨酸酶活性,但其美白活性及其作用机理还有待进一步研究。

The Polysaccharide was prepared by superfine comminution of Poria cocos( Schw.) Wolf powder and hot water extraction. Then the PW-P1, PW-P2 and PW-P3 of different molecular weights were obtained by ultrafiltration membrane with the relative molecular weight of 5 kDa and 10 kDa, after alcohol precipitation and freeze drying. The anti-inflammatory and whitening activities of DPPH free radical scavenging, NO inflammation induced by LPS and tyrosinase activity were tested in vitro. The results showed that the crude polysaccharide contents of PW-P1, PW-P2 and PW-P3 were 96.46%, 93.18% and 92.25%, respectively, and it showed good DPPH free radical scavenging activity. The IC50 of PW-P3 on DPPH free radical scavenging rate was 0.45 mg·mL^(-1). The IC50 of PW-P1 and PW-P2 was greater than 0.8 mg·mL^(-1). PW-P1, PW-P2 and PW-P3 at the concentration of 50 μg·mL^(-1)-1 000 μg·mL^(-1) showed significant inhibitory effect on LPS-induced NO production, and PW-P2 and PW-P3 showed superior inhibitory effect on NO production than PW-P1. PW-P1, PW-P2 and PW-P3 can inhibit tyrosinase activity, but their whitening activity and its mechanism need to be further studied.