近年來，通量平衡分析方法已廣泛應用在微生物系統中，可預測微生物的生長和產物的生成。以重建的基因尺寸新陳代謝網路為基礎，本研究建立了一個以電腦模擬釀酒酵母代謝的動態通量平衡分析模式。此動態平衡分析模式結合了細胞內微生物詳細的生化反應和細胞外主要代謝物的質量平衡方程式，真實地描述釀酒酵母的新陳代謝。此外，利用最適化條件搜尋，本研究亦求得雙基質饋料批次發酵下，最大的酒精生產速率，研究中發現利用高濃度葡萄糖進料，使發酵槽中維持低葡萄糖濃度，進而增加木糖的消耗速率，在無氧和通氧的環境下，可得到的酒精生產速率分別為1.3281 g ethanol/L/hr 和 1.9526 g ethanol/L/hr。由此可知，先利用通氧的環境使菌種有良好的生長，可以提升雙基質饋料批次發酵之酒精的生產速率。

Flux balance analysis (FBA) is a popular approach which is used extensively for predicting cellular growth and product secretion patterns in microbial systems. A dynamic flux balance model based on a genome-scale metabolic network reconstruction is developed for in silico analysis of Saccharomyces cerevisiae fermentation. The model couples a detailed steady-state description of primary carbon metabolism with dynamic mass balances on key extracellular species. In addition, model-based dynamic optimization is performed to determine fed-batch operation policies that maximize ethanol productivity on glucose and xylose. Therefore, A optimized fed-batch process designed to maintain a low level of glucose throughout the course of xylose conversion provide ethanol productivity of 1.3281 g ethanol/L/hr and 1.9526 g ethanol/L/hr in anaerobic and aerobic conditions, respectively. The analysis results suggest that enhancements in biomass yield are most beneficial for the increase of fed-batch ethanol productivity in aerobic fermentation.

[中文]
[1] 楊紹廣，「通量平衡分析模式在酒精發酵上的應用」，碩士論文，國立台灣科
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[2] 王子興，「以cybernetic模式建構Pichia stipitis菌之酒精發酵模式與
操作策略分析」，碩士論文，國立台灣科技大學，台北(2009)

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