醋酸菌发酵产细菌纤维素培养基和培养条件的优化

以实验室筛选、保藏的汉逊氏葡糖酸醋杆菌(Gluconacetobacter hansenii)为出发菌株,通过单因素实验结合响应面分析,对其产细菌纤维素(bacterial cellulose,BC)的发酵培养基进行优化,并以优化过后的发酵培养基为基础,通过单因素实验结合正交实验,对培养条件进行优化。实验结果如下:当培养基组成为(g/L):蔗糖10,酵母粉9.36,蛋白胨5,磷酸氢二钠2.86,柠檬酸0.3,pH5.96时,BC膜干重最高,约为4.779 g/L。在此基础上,采用接种量10%、装液量50 mL、培养温度30 ℃、培养时间10 d的培养条件,可以获得干重为8.515 g/L的BC膜干重,比优化前的2.022 g/L提高了300%以上。

Optimization of fermentation medium and culture conditions of producing bacterial cellulose of Gluconacetobacter hensennii strain

Single factors tests combined response surface design were carried out to optimize fermentation medium of producing bacterial cellulose of Gluconacetobacter hensennii strain. The strain was isolated by our laboratory from traditional kombucha. Besides,based on the optimized medium,culture conditions were optimized by single factors tests and orthogonal experiments. The results showed that the optimal medium(g/L)contained 10 g sucrose,9.36 g yeast extract powder,5 g peptone,2.86 g disodium hydrogen phosphate,0.3 g citric acid monohydrate,pH5.96. Under the condition,BC dry weight was 4.779 g/L. Based on the medium,performed fermenting progress in 50 mL medium with 10% seed solution at 30℃ for 10 d. Under the condition,BC dry weights could arrived 8.515 g/L and the growth rate was more than 300% compared to control group.