改善Pichia stipites CBS6054生產生質酒精之代謝通量分析

Flux Balance Analysis for Improving Product Bioethanol by Pichia Stipites CBS6054

鄧永強(Weng-Keong Tang)

指導教授 ： 王逢盛

國立中正大學/工學院/化學工程學系/碩士(2015年)

摘要

生質酒精是利用微生物醱酵把生質源料中的醣分轉化為酒精。而製造生質酒精的源料大致可分為糖質原料、澱粉質原料、纖維質原料。其中，纖維質原料經過水解程序可得到五碳糖與六碳糖(大部分是木糖與葡萄糖)。例如蔗渣是製糖的廢棄物，主要由木質纖維素組成，木質纖維素含有纖維素（約占38 ~ 50 ％）、半纖維素（約占23 ~32 ％）、木質素（約占15 ~ 25 ％），其中的纖維素與半纖維素可被水解成木糖以及葡萄糖。本研究透過代謝網路模型iTL885模擬P. stipitis CBS6054生產酒精的情況，利用通量平衡分析（Flux Balance Analysis, FBA）計算Pichia stipitis利用葡萄糖及木糖生產酒精的速率。模擬結果發現，當葡萄糖和木糖同時存在，葡萄糖的攝取速率為15.37 mmol/g dry weight/h，木糖的攝取速率為2.87 mmol/g dry weight/h，酒精的生產速率為21.14 mmol/g dry weight/h，符合P. stipitis先利用葡萄糖進行醱酵，直到葡萄糖消耗完畢，才開始有效利用木糖的特性，說明iTL885有非常高的可信性。

關鍵字

通量平衡分析 ； 生質酒精

並列摘要

Bioethanol, ethanol, which is converted from the sugar in biomass by microbial fermentation. The raw material of bioethanol production is roughly divided into sugar, starch material and fibrous material. Pentose and hexose can be obtained by the hydrolysis of fibrous material (mostly xylose and glucose).Such as bagasse, which is the waste after sugar production, is composed of lignocellulose mainly, containing cellulose (about 38 to 50%), hemicellulose (about 23 to 32%), lignin (about 15 to 25%), and then cellulose and hemicellulose can be hydrolyzed to xylose and glucose.This study simulate Pichia stipitis CBS6054 ethanol production by metabolic network model iTL885, using Flux Balance Analysis(FBA) to calculate the ethanol productivity by P. stipitis utilizing glucose and xylose. As a result of simulation, the uptake flux of glucose and xylose are 15.37 mmol/g dry weight/h and 2.87 mmol/g dry weight/h respectively, the production flux of ethanol is 21.14 mmol/g dry weight/h when glucose and xylose coexisting, conform the property of P. stipitis that is first using glucose to ferment, until the glucose had been consumed, so we can trust the model iTL885 is collect.

並列關鍵字

flux balance analysis ； bioethanol ； P. stipitis

參考文獻

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