摘要
利用Sigmoid函数构建了灵芝深层发酵生产胞外多糖和灵芝酸的非结构动力学模型，并根据Boltzmann拟合求解出模型参数，模型预测值能够较好地吻合实验所测值．细胞最大比生长速率μmax为4．63×10^-2h^-1，葡萄糖最大比消耗速率qs，max为6．70×10^-2h^-1，胞外多糖最大比合成速率qEPS,max为4．65×10^-3h^-1，灵芝酸最大比合成速率qGA,max为9．09×10^-4h^-1．灵芝胞外多糖的合成与细胞的生长呈现部分偶联关系；灵芝酸的合成与细胞的生长呈现偶联关系，偶联系数αGA为0．0204g g^-1．胞外多糖对葡萄糖的最大得率系数（YEPS/S）为0．214gg^-1；灵芝发酵40～80h代谢碳流迅速从菌体自身生长迁移至胞外多糖合成，用于合成胞外多糖的最大碳流为23．6％．
The unstructured kinetics of exopolysaccharide （EPS） and ganoderic acid （GA） production by submerged culture of Ganoderma lucidum in bioreactors was investigated based on Sigmoid model. The parameters of the model were determined by Boltzmann simulation, and the value predicted by the model matched well with that obtained from the investigation. The maximum specific cell growth rate （μmax）. the maximum specific glucose consumption rate （qs, max）, the maximum specific EPS production rate （qEPS,max ） and the maximum specific GA production rate （qGA,max ） was 4.63×10^-2h^-1, 6.70×10^-2h^-1, 4.65×10^-3h^-1 and 9.09×10^-4h^-1, respectively. The kinetics of EPS production followed a combined growth-associated and non-growth-associated behavior, whereas GA production followed a growth-associated behavior with a constant associated coefficient （αGA） 0.020 4 g g^-1. The maximum yield coefficient of EPS from glucose （YEPS/S） was 0.214 g g^-1. Carbon flux was rapidly shifted from biomass accumulation to EPS synthesis during 40-80 h in the fermentation process of G. lucidum, and the maximum carbon flux to EPS synthesis was 23.6%. Fig 4, Tab 1, Ref 15
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2008年第4期562-565,共4页
Chinese Journal of Applied and Environmental Biology
