蛹虫草液体发酵产物冻干粉的抗氧化活性及保肝作用

目的研究蛹虫草液体发酵产物冻干粉的抗氧化活性及保肝作用。方法采用真空冷冻干燥的方法将蛹虫草液体发酵产物制成干粉并对冻干粉主要成分进行分析测定，通过DPPH自由基清除实验和衰老小鼠模型验证蛹虫草发酵产物冻干粉的抗氧化活性，通过小鼠急性肝损伤实验研究冻干粉的保肝作用，采用急性毒性试验验证冻干粉的安全性。结果蛹虫草发酵产物冻干粉含丰富的粗纤维、粗多糖、粗三萜及黄酮类物质。蛹虫草发酵产物冻干粉对DPPH自由基的半数有效浓度（EC50）为8．12mg／mL，在16mg／mL时对DPPH自由基的清除率为61．56％，与0．02mg／mL的维生素C（Vc）清除能力相当；蛹虫草发酵产物能显著提高衰老模型小鼠血清和肝脏中的总超氧化物歧化酶（T-SOD）、谷胱甘肽过氧化物酶（GSH-px）活力水平，降低丙二醛（MDA）含量，高剂量组的抗衰老效果与阳性药Vc组的抗氧化能力相当。小鼠急性肝损伤试验结果显示，冻干粉能有效降低模型组小鼠血液中门冬氨酸氨基转移酶（AST）与丙氨酸氨基转移酶（ALT）水平（P〈0．05）。冻干粉的半数致死量（LD50）远大于国家无毒标准15g／kg，属于无毒级别。结论蛹虫草发酵产物具有良好的抗氧化活性和保肝作用，且安全无毒。

Anti-oxidative activity and hepatoprotective effect of lyophUized powder of liquid fermentation products from Cordyceps militaris

Objective To test the anti-oxidative activity of lyophilized powder of liquid fermentation products from Cordyceps militaris. Methods The lyophilized powder of liquid fermentation products from Cordyceps militaris was prepared by freezing and drying process, then, the anti-oxidative capacity of lyophilized powder was measured by DPPH tests in vitro and the aging mouse model was induced by D-galactose in vivo. Results The results indicated that the EC50 value of the lyophilized powder on scavenging DPPH free radical activity was 8.12 mg/mL, comparing to Vitamin C （Vc）, and the scavenging DPPH activity of the lyophilized powder with the concentration of 16 mg/mL was equal to that of 0.02 mg/mL Vc; The aging mice model tests indicated the lyophilized powder could effectively improve the levels of total superoxide dismutase （T-SOD） and glutathione peroxidase （GSH-px）, reduce the level of malondiadehyde （MDA） in serum and liver of aging mice （P 〈 0.05）. The acute liver injury test results showed that the lyophilized powder could effectively reduce the contents of aspartate transaminase （GOT） and glutamic-pyruvic transaminase （GPT） in serum of mice with acute liver injury （P 〈 0.05）. Toxic tests indicated that the lyophitized belonged to the Non-toxic level. Conclusion The Cordyceps militaris liquid fermentation products as a safety food have strong anti-oxidative activity and hepatoprotective effect.