土曲霉菌体形态对衣康酸生产效率的影响

Effect of Morphology of Aspergillus terreus on Itaconic Acid Production Efficiency

以土曲霉Aspergillus terreus发酵生产衣康酸(IA),通过改变孢子接种量和摇瓶类型,获得A.terreus在深层发酵过程中的3种形态:菌丝、菌团和菌球,研究了3种形态下发酵液的流变性能和IA生产效率.结果表明,当A.terreus为菌团时单位细胞合成IA能力和消耗葡萄糖能力最高.通过调节培养基中KH2PO4浓度和培养温度考察菌团大小对IA积累的影响,单位细胞合成IA能力和消耗葡萄糖能力与菌团直径密切相关,KH2PO4为0、35℃时菌团直径最佳,为0.40～0.50mm,单位细胞合成IA能力和消耗葡萄糖能力分别为4.42g/g和8.38g/g,比KH2PO4 0.05g/L、37℃时提高35.4%和27.5%.

Using Aspergillus terreus to produce itaconic acid （IA）, its three morphologies （dispersed mycelia, clump and pellet） were obtained by manipulating inoculum level and flask shape. Then the effects of three morphologies on broth rheology and IA production showed that higher yield of IA on DCW and yield of glucose on DCW were achieved at the clump, than that of dispersed mycelia and pellet. Furthermore, the effect of clump diameter on IA production was investigated by changing KH2PO4 content and culture temperature, which demonstrated that the yield of IA on DCW and yield of glucose on DCW were closely correlated with clump diameter. The optimal clump diameter range for higher yield of IA on DCW was 0.40-0.50 mm, and the yield of IA on DCW and the yield of glucose on DCW were achieved at 4.42 g/g and 8.38 g/g under the conditions of KH2PO4 content 0 and 35 ℃, which was 35.4% and 27.5% higher than the corresponding values of KH2PO4 content 0.05 g/L and 37 ℃, respectively.