蓝睡莲多酚类物质抗氧化与降糖作用的研究

Studies on the biological activities of phenolics from Nymphaea stellata willd

测定蓝睡莲甲醇提取物中总酚和总黄酮的含量并研究其抗氧化及降糖活性。方法:通过改进的Folin-Ciocalteu法及比色法,测定提取物中总酚、总黄酮的含量;对提取物的ABTS自由基清除作用、抗氧化能力、酪氨酸酶抑制活性以及α-葡萄糖苷酶抑制活性进行测定。结果:蓝睡莲甲醇提取物总酚含量为(152±12.3)mg/g,总黄酮含量为(51±3.5)mg/g;对酪氨酸酶的半数抑制浓度为(420±22.5)μg/mL(单酚)、(173±10.8)μg/mL(双酚);提取物浓度4μg/mL时,对ABTS自由基清除活力达86.7%;体外大鼠α-葡萄糖苷酶活性抑制实验表明,提取物对麦芽糖酶具有明显抑制作用,而对大鼠小肠蔗糖酶和猪胰α-淀粉酶的抑制作用不明显。结论:蓝睡莲可作为抗氧化剂,褪色剂和抗糖尿病成分,应用于功能性食品、医药和化妆品行业。

The methanol extract from Nymphaea stellata willd.flowers was explored to evaluate their total phenols and flavonoids,together with evaluating their antioxidant,tyrosinase and α-glucosidase inhibitory properties in vitro assay.The total phenols and flavonoids were（152±12.3） mg/g and（51±3.5） mg/g,respectively.This extract showed the high free radical scavenging activity（86.7% at the high concentration of 4 g/mL）,which was higher than that of the positive control,Trolox.Meanwhile,this extract showed the potency for tyrosinase inhibition,the EC50 values of diphenolase and monophenolase were（420±22.5） μg/mL and（173±10.8） μg/mL,respectively.Furthermore,this extract was found to show the potent α-glucosidase inhibition on maltose hydrolyzing activity and show low activity against rat intestinal sucrase and porcine pancreatic α-amylase.From these results,we can conclude that N.stellata could be useful in functional foods,medicines and cosmetics as a natural resource.