混合培养发酵L-苹果酸的研究

A Study on L-Malic Acid Fermentation by Mixed Culture

采用 A- 2 3菌株和 V- 81菌株混合培养发酵 L -苹果酸 ,分别探讨碳源浓度对 A- 2 3菌株和 V-81菌株发酵水平的影响 .试验表明 ,A- 2 3菌株产延胡索酸能力强 ,V- 81菌株具有高活性延胡索酸酶 .在此基础上 ,研究 A- 2 3菌株和 V- 81菌株混合培养方式对发酵 L-苹果酸的影响 .结果表明 ,A- 2 3菌株接入含有 150 g· L-1葡萄糖的混合发酵培养基中培养 3d,后接入 V- 81菌株并继续培养 2 d,产酸水平最高 ,L-苹果酸浓度达 73.3g· L-1,对投糖浓度的摩尔转化率达 6 5.6 % .

Lmalic acid fermentation was performed by a mixed culture of strain A 23 and strain V 81. The effect of concentration of carbon source on the fermentation level of both strain A 23 and strain V 81 was investigated. The experimental results showed that strain A 23 was very capable of producing fumaric acid while strain V 81 had strong fumarase activity. On the basis of above investigation, the influence of the way for a mixed culture of strain A 23 and strain V 81 on L malic acid fermantation was further studied. The result indicated that the highest L malic acid yield was acquired when strain A 23 was inoculated and cultured in the mixed fermentation medium containing 150 g·L -1 glucose for 3 days, then strain V 81 was inoculated and cultured for 2 days. The concentration of L malic acid reached 73.3 g·L -1 while its molar conversion rate to initial glucose concentration in the medium amounted to 65.6%.