蛹虫草SOD高活性菌株筛选及液体培养条件优化

Screening and fermentation optimization of Cordyceps militaris having high SOD activity

建立了一种较为系统的蛹虫草液体发酵产SOD的培养条件。以4种来源蛹虫草( Cordyceps militaris )菌株YCC-B、YCC-C、YCC-W、YCC-Y为研究对象,以生物量和SOD活性为指标,筛选出SOD高活性菌株。之后优化SOD高活性菌株的液体发酵条件,以生物量、SOD清除超氧阴离子能力(清除率)、酶活力和比活力为测定指标,选取接种量、装液量和pH展开3因素3水平的正交实验。经筛选,得到SOD高活性菌株为YCC-W。通过优化YCC-W的液体发酵条件,得出最佳组合为接种量4%,装液量100 mL/250 mL和pH 5.5。SOD清除率可提高41.17%,达到54.84%;SOD 酶活力可提高42.04%,达到19.74 U/mL;比活力可提高44.23%,达到56.34 U/mg。该研究提供了通过蛹虫草菌丝体发酵产SOD的方法,在替代传统动物血液获取SOD上具有一定的应用前景;通过系统优化发酵条件SOD活性得到显著提升,通过继续扩大实验规模,有望用于SOD的规模化生产。

To establish a fermentation process to produce SOD by Cordyceps militaris, the biomass and SOD activity of the mycelia from four strains of C. militaris ,YCC-B, YCC-C, YCC-W, and YCC-Y, were examined. Of which, C. militaris YCC-W produced the highest activity of SOD. The optimized fermentation condition for producing SOD from YCC-W was as follows: 4% inoculum, 100 mL working volume in a 250 mL flask, and at pH=5.5. Under this condition, the SOD activity was 19.74 U/mL (increased 42.04%) and the specific activity was 56.34 U/mg (enhanced by 44.23%). Besides, the removal rate of SOD increased by 41.17% and reached 54.84%. In conclusion, this study provides a new method for producing SOD by C. militaris fermentation, which shows a certain application prospect in replacing traditional animal blood to obtain SOD.