产胞外多糖泰山羊肚菌液体培养条件的优化

对泰山羊肚菌产胞外多糖 (exopolysaccharides,EPS)的液体培养基组成和发酵条件进行了优化 ,最适碳源是葡萄糖 ,最适氮源是NH4NO3 。正交试验确定最佳培养基组成为麸皮 2 0 0 g/L ,葡萄糖 30 g/L ,NH4NO3 1g/L ,KH2 PO42 g/L ,MgSO4·7H2 O 1 5 g/L。最佳发酵条件为 2 5℃ ,起始 pH值 6 5 ,装液量 10 0mL/瓶 ,接种量10 % ,摇床转速 2 0 0r/min ,发酵时间 4d。在此条件下 ,其胞外多糖含量 (2 135 4 4 1mg/L)比对照(14 5 4 6 39mg/L)提高了 4 6 8%。

Liquid Fermentation Conditions of Exopolysaccharides Produced by Morchella esculenta

The optimum fermentation culture and fermentation conditions of exopolysaccharides(EPS) produced by Morchella esculenta were obtained. The experiments for EPS production showed that glucose and NH 4NO 3 are the optimum carbon and nitrogen sources. The fermentation medium obtained by orthogonal tests of the fermentations contains bran 200 g/L,glucose 30 g/L,NH 4NO 3 1 g/L,KH 2PO 4 2 g/L,MgSO 4·7H 2O 1.5 g/L.The optimum fermentation conditions are initial pH 6.5, inoculation volume 10%, fermentation temperature 25℃,medium volume in flask 100 ml and fermentetion time 4days. Morchella esculenta produces EPS with the productivity of 2 135.441 μg/mL under the optimum conditions, which is 46.8% higher than that under the original conditions (1 454.639 mg/L).