海洋中海藻糖产生菌的筛选及发酵条件优化

从180余份海水、海泥样品中筛选得到60株产海藻糖较高的菌株,编号为2-14的菌株海藻糖产量最高,为127.9mg/g cell。对2-14菌株进行形态特征、培养特征及生理生化试验,鉴定该菌株为红酵母属(Rhodotorula sp.)。研究摇瓶发酵条件对红酵母海藻糖产量的影响,结果为:初始pH5.5,发酵温度28℃,装液量75mL(250mL三角瓶中)。采用优化后发酵条件红酵母海藻糖产量为193.3mg/g cell,优化前对照值为132.1mg/g cell,优化后的结果是优化前的1.46倍。在5L发酵罐中培养得到最佳发酵时间为54h,发酵罐培养发酵液中海藻糖含量最高达2.5g/L,为摇瓶培养的1.6倍。

Screening and Fermentation Optimization of Trehalose-Producing Strain from Marine

60 strains capable of producing trehalose were screened out from 180 seawater and marine mud samples, strain 2-14 could produce the highest trehalose which was 127.9 mg/g cell. Strain 2-14 was identified as Rhodotorula sp. based on its morphological properties, cultural characteristics, physiological and biochemical properties. The effect of shake flask fermentation conditions of the strain on trehalose production was studied, the optimum fermentation conditions were determined as follows： the initial pH 5.5, temperature 28 ℃, broth volume 75 mL （i.e., 30% for a 250 mL culture flask）. After the adoption of optimization condition trehalose yield was 193.3 mg/g cell which was 1.46 times as that of control value at 132.1 mg/g cell before optimization. The optimum culture time was 54 h in 5 L fermentor, trehalose yield was 2.5 g/L which was 1.6 times as that in shake flask.