pH值对普鲁兰多糖发酵的影响及其机理分析

摘要

Influence of different pH was studied to influence on pullulan production by Aureobsidium pullulans CGMCCNO.7055.UDP-glucose level and its related enzymes that was phosphoglucomutase(PGM)and Uridine diphosphate glucose pyrophosphorylase(UGPase)were measured,which was used to analyze the fermentation mechanism.It was found a method that was two-phase controlling pH for fermentation.It showed that the first phase was controlled initial pH value to 6.0 in 24 h of the fermentation,then the second phase was controlled constant pH to 5 after fermenting 24 h(OD6200.5)调控pH值到5.0并维持恒定,此阶段磷酸葡萄糖变位酶(PGM)和UDPG焦磷酸化酶(UGPase)活性最高.采用该方法使普鲁兰多糖产量达到(92.5±2.41)g/L,生物量达到(13.87± 0.89)g/L,经相关性检验发现该发酵条件下普鲁兰多糖产量与尿苷二磷酸葡萄糖含量呈显著负相关关系.