摘要
通过正交试验研究米根霉AS3.819利用葡萄糖发酵生产L-乳酸时,发酵培养基中葡萄糖、(NH4)2SO4、KH2PO4、ZnSO4.7H2O、MgSO4对发酵的影响。确定的最佳发酵培养基组成:葡萄糖80 g/L、(NH4)2SO4 2 g/L、KH2PO4 0.3 g/L、ZnSO4.7H2O 0.05 g/L、MgSO4 0.3 g/L。在此培养基组中平均发酵产L-乳酸61.5 g/L,对葡萄糖的平均转化率为76.9%。初步建立米根霉AS3.819利用葡萄糖发酵生产L-乳酸的动力学模型,并通过发酵动力学试验获得到模型参数,对培养基中初始葡萄糖质量浓度分别为72、74 g/L的发酵过程进行预报。结果表明,建立的动力学模型能较好地描述米根霉发酵生产L-乳酸的过程;L-乳酸的生成机制是以生长机制为主的混合动力学机制。
The optimal composition of culture medium for lactic acid fermentation by Rhizopus oryzae AS3.819 using glucose was detemlined by orthogonal experiments as glucose 80 g/L, （NH4）2SO4 2 g/L, KH2PO4 0.3 g/L, ZnSO4·7H2O 0.05 g/L and MgSO4 0.3 g/L. At this optimum culture medium, the lactic acid concentration reached to 61.5 g/L, indicating 76.9% conversation ratio of glucose. Kinetics model of L-actic acid production by Rhizopus oryzae AS3.819 using glucose was setup with consideration of product inhibition on cell growth, and fermentation kinetic experimental results at optimal culture medium of initial glucose 80 g/L were used for the determination of kinetic parameters. Simulated results indicated that the formation of lactic acid by Rhizopus oryzae under this condition is a combined kinetic mechanism, mainly dominated by cell growth rate. Optimization kinetic parameters have been successfully used to predict the fermentation processes with initial glucose concentration of 72 g/L,74 g/L respectively.
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2009年第2期18-22,共5页
Journal of Chinese Institute Of Food Science and Technology
关键词
米根霉
L-乳酸
培养基组成
发酵动力学
Rhizopus oryzae L-lactic acid Culture medium composition Fermentation kinetics
