反应分离耦合技术生产L-苹果酸工艺过程的优化研究

Study on the Optimal Conditions in Simultaneous Reaction and Separation for L-malic Acid Production

运用生物反应分离耦合原理 ,以富马酸钙为底物 ,采用游离延胡索酸酶 ,直接转化生成苹果酸钙。该法相对目前广泛采用的包埋式固定化方法具有工艺流程短、操作简便、转化率、收率高等特点。研究结果表明 ,转化温度为 40℃、pH为 7 0～ 7 5时 ,每升延胡索酸酶液能在 2 0～ 2 8h间将 3 2kg的富马酸钙转化生成苹果酸钙 ,转化率高达 99 9% ,富马酸在产品中的残留在 0 1%左右 ,产品符合美国药典标准 ,成本与化学合成法生产的DL

Based on the principle of coupling reaction and separation process,free cells containing fumarase were used for producing L\|malic acid.The calcium fumarate was used as substrate to produce calcium malate directly.This new method was more advantageous than the traditional immobilized cells conversion system in aspects such as simple equipment and operation,high conversion efficiency and the yield of product.The results showed that at reaction temperature 40℃,pH7.0～7.5,reaction time 20～28h,the conversion efficiency was up to 99.9% and about 3.2kg calcium fumarate was converted to calcium malate per liter enzyme suspension.Also,L\|malic acid produced in free fumarase system satisfied USP criterion,the residual fumaric acid was less than 0.1% and the cost was approximately to that of DL\|malic acid produced by chemical synthesis.