中文摘要：

为解决天然发状念珠藻生长缓慢的问题,从天然藻体中分离出细胞对其进行液体悬浮培养。结果表明,液体悬浮培养可以显著提高发状念珠藻细胞的生长速度,同时提高发状念珠藻胞外多糖的产量。采用BG-11培养基,添加2.5 g/L硝酸钠,培养温度25℃,光照强度40μmol/（m^2.s）,转速130 r/min,培养20 d细胞干质量浓度达到1.05 g/L,胞外多糖产量89.9 mg/L。培养发状念珠藻细胞的基本成分和细胞培养液的HPLC指纹图谱分析表明其生化组成和多糖的合成与天然发状念珠藻相似。与其他人工培养方法相比,液体悬浮培养更适合大规模工业化生产。

英文摘要：

Nostoc flagelliforme grows extremely slow in nature.To solve this problem,the liquid suspension culture of Nostoc flagelliforme cells was carried out.The results show that liquid suspension culture can increase the growth rate of cells prominently and the accumulation of exopolysaccarides（EPS） is increased too.When it was cultured in BG-11 medium added with 2.5 g/L of NaNO3 at 25 ℃,light intensity of 40 μmol/（m^2·s）,rotating speed of 130 r/min,the cells grew well.After 20 d cultivation,1.05 g/L cell density and 89.9 mg/L EPS yield were achieved respectively.The biochemical compositions of natural and cultivated Nostoc flagelliforme cells were assayed as well as the fingerprint of cell cultures were analyzed by HPLC.The results show that the cultivated cells and the natural algal cells have the similar components.This technology is more feasible for industrialized production than other artificial culture.