响应面法优化蛹虫草深层培养产菌丝及虫草素的发酵工艺

通过单因素试验和响应面设计对蛹虫草液体深层发酵工艺进行优化。结果显示,最适的碳氮源是葡萄糖和蛋白胨;培养的适宜条件:装液量100 mL,初始pH值5.0,发酵周期为8 d;对于虫草素产量影响最显著的无机盐是FeSO_4。Plackett-Burman设计从8个因子中筛选出4个显著因子,经最陡爬坡和响应面设计,结果表明,葡萄糖31.58 g/L,蛋白胨34.48 g/L,腺嘌呤0.88 g/L,甘氨酸15.48 g/L为发酵培养基的最佳组合;优化条件下,虫草素的产量为917.53 mg/L,生物量为30.06 g/L,较优化前分别提高了108.30%和29.06%。

Enhanced Production of Mycelia Biomass and Cordycepin by Submerged Culture of Cordycepsmilitaris with Response Surface Methodology

Effects of medium composition and fermentation conditions on production of mycelia and Cordycepin by traditional Chinese edible mushroom,Cordycepsmilitaris are investigated by submerged cultivation.The favorable carbon sources and nitrogen sources are glucose and peptone respectively.The optional culture conditionsare obtained as follows:100 mL of medium working volume in the 250 mL shake-flask,initial pH of medium at 5,and a fermentation period of 8 d.Among six mental ions,Ferrous sulfate is found to be the most significant factor increasing concentration of cordycepin in fermentation broth.To enhance further production of mycelia and cordycepin,the effects of medium composition is studied with the utilization of response surface methodology.Response surface analysis reveals that the ideal composition of medium is as follows:31.58 g/L glucose,34.48 g/L peptone,0.88 g/L adenine,and 15.48 g/L glycine.Under the optional conditions the maximum concentration of mycelia and cordycepinare 30.06 g/L and 917.53 mg/L,respectively,which are 29.06%and 108.30%higher thanresults prior to optimization.