本研究首先以數學模式描述Enterococcus faecalis RKY1及乳酸在批式反應器及饋料批式反應器的生長情形。接著利用基因演算法尋找批式製程最適化的操作條件(pH、初始細菌濃度、初始基質濃度及發酵時間)，以獲得最高的乳酸生產速率，經由最適化後得到的乳酸生產速率為5.1023(g/l*h)。最後以三個目標函數分別在不同的糖蜜進料段數下，利用基因演算法尋找饋料批式製程最佳的進料策略及操作條件，以獲得最高的乳酸產量，經由最適化後得到最高乳酸產量為113.23(g/l)。

In the first part of this research, we describe Enterococcus faecalis RKY1 growth and lactic acid production in a batch reactor and a fed-batch reactor by mathematical model. Then we search the optimal operational conditions by Genetic Algorithm to get the highest lactic productivity. The productivity is 5.1023(g/l*h).
For getting the largest lactic acid amount, we choose three objective functions to find the optimal operational conditions in different fragments by Genetic Algorithm in the finial part of this research. The largest lactic acid amount we get is 113.23(g/l).

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