胶红酵母J6发酵培养基的优化及其生长曲线的绘制

摘要

In this study,medium composition was optimized for improving carotenoid yield and investigating the growth characteristics of Rhodotorula mucilaginosa J6 in liquid fermentation,and the growth curve was plotted.On the basis of the fermentation medium whose formula were as follows:2% glucose,2% peptone,1% yeast extract,2% sodium chloride and 0. 05% magnesium sulfate,the optimization experiment of fermentation medium of the R. mucilaginosa J6 strain about selecting types of carbon sources,nitrogen sources,inorganic salts and medium components was conducted by orthogonal test.The content of pigment(carotenoids) and biomass were used as the evaluation index for optimizing the fermentation medium of R. mucilaginosa J6. The R. mucilaginosa J6 was inoculated in 12 bottles with fermentation medium,and a flask of fermented liquid was removed every 6 h.The number of live bacteria and total bacteria of R.mucilaginosa J6 were determined by blood count plate methodology,and then the growth curve was drawn. The results showed that,compared to the previous strain,the biomass of R. mucilaginosa J6 in optimal fermentation medium was 16.791 0 g/L,which was increased by 161.39%, and the pigment yield was 331.406 μg/g,which was increased by 151.78%.The optimal fermentation medium formula was 2% trehalose,2% peptone,2% yeast extract,0. 5% beef extract,2% sodium chloride and 0.025% manganese sulfate.The growth curve of R.mucilaginosa J6 was plotted. The lag phase,logarithmic growth phase,stationary phase and decline phase of R.mucilaginosa J6 were the first 6—18 h,18—36 h,36—48 h and 48—72 h,respectively.%为了提高胶红酵母J6的类胡萝卜素产量,探讨其液体发酵的生长特性,对其发酵培养基成分进行优化,并绘制生长曲线.用2%葡萄糖、2%蛋白胨、1%酵母膏、2% NaCl和0.05% MgSO4配制发酵培养基,在此基础上进行碳源、氮源、无机盐的种类选择及培养基成分的正交试验,以色素(类胡萝卜素)含量和生物量作为胶红酵母J6发酵培养基优化效果的评价指标.将胶红酵母J6接种于12瓶发酵培养基中,每隔6 h取出1瓶发酵液,用血球计数板法测定胶红酵母J6的活菌数和总菌数,绘制生长曲线.结果表明,发酵培养基优化后,胶红酵母J6的生物量达到16.7910 g/L,比优化前提高了161.39%;色素含量为331.406 μg/g,比优化前提高了151.78%;综合考虑,优化后的发酵培养基配方是:2%海藻糖、2%蛋白胨、2%酵母膏、0.5%牛肉膏、2% NaCl 和0.025% MnSO4.绘制出了胶红酵母J6生长曲线,6~18 h为迟缓期,18~36 h为对数生长期,36~48 h为稳定期,48~72 h为衰亡期.