透明质酸产生菌的化学诱变及发酵条件探索

Studies on chemical mutation and fermentational condition of streptococcus zooepidemicus

以兽疫链球菌(Streptococcuszooepidemicus)C55151为原始菌种,经N-甲基-N -硝基-N-亚硝基胍(NTG)诱变处理,获得一株高产透明质酸(Hyaluronicacid,HA)的变异株J18,其HA产量较原始株提高一倍.利用正交设计试验探索出该变异株的最佳发酵培养基配比为葡萄糖50g/L,酵母膏30g/L,硫酸镁0.5g/L.发现添加十二烷基硫酸钠(SDS)能够大幅度提高HA产量.同时对原始株、变异株的发酵过程进行了研究,发现变异株J18在发酵的任何时间,其HA产量都高于原始菌种,且菌体浓度与发酵液中的葡萄糖浓度及pH值呈负相关性.

After wild streptococcus zooepidemicus C55151 was mutated byN-methyl-N-nitro-N-nitrosogua-nidin(NTG), a mutanted strain(J18) capable of producing HA in a high yield was acquired, which can produce HA twice as much as the original strain. The optimum fermentation culture medium was studied by an orthogonal method, which contained glucose 50 g/L, yeast extract paste 30 g/L, (MgSO_4) (0.5) g/L. It was found that SDS can improve the yield of HA obviously. The kinetics of the HA fermentation process of the original one was compared with that of the mutanted strain.