化学法测定发酵液中的C群流脑多糖

Determinating polysaccharide of N. meninyitidis group C in fermentation broth by chemistry method

目的 根据《中国药典》（2010年版）收入的C群流脑多糖测定的唾液酸法,结合发酵工艺过程监测的需要,建立C群脑膜炎球菌发酵液中C群流脑多糖定量测定的方法.方法 发酵液经离心（12000r/min,10min）除去菌体,上清液用1.5μL10％十六烷基三甲基溴化铵（CTAB）沉淀多糖.多糖用1mol/L CaC12溶液溶解后进行显色、有机相萃取.有机相于波长580nm测定光吸收值,从标准曲线得到唾液酸的浓度并计算出发酵液中C群流脑多糖的浓度.结果 试验表明此法用于发酵液中C群流脑多糖含量的测定稳定性好,回收率在85％～115％,能够很好反映C群脑膜炎球菌发酵过程中C群流脑多糖的产量变化.结论 本法准确性高,重复性好,结果可靠,可用于发酵液中C群流脑多糖的定量分析.

Objective To create a method for determinating polysaccharide of N. meninyitidis group C in fermentation broth, which developed by adopting the method from Chinese Pharmacopoeia 2010 edition and considering the need of monitoring the fermentation process. Methods The fermentation broth is centrifuged by 12000r/min, 10min, polysaccharide is separated from the supernatant by adding 1.5μL 10% hexadecyl trimethyl -ammonium bromide（CTAB）. The polysaccharide will be, dissolved by lmol/L CaC12, then colored and extracted by organic phase which be mensured its absorbance at 580rim by using the spectrophotometer. We can get sialic acid concentration by using standard curve and calculate polysaccharide concentration in fermentation. Results The tests indicated that the recovery for the sample was in the range 85% to 115%, and stability and repeatability of results were good. Conclusion The method can be used for determinating polysaccharide ofN. meninyitidis group C from fermentation broth.