Studies on optimal co-cultural conditions for microorganism culture producing biomass generating ethanol

• Main Authors: Yeh Tsung Wei, 葉宗葦
• Other Authors: 劉裕國
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/20224277511228554765

碩士 === 長庚大學 === 化工與材料工程研究所 === 95 === The purpose of this study is to produce alternative energy - ethanol from the agricultural waste including cellulose, hemicellulose and lignin, etc. We will develop a new co-culture system of the simultaneous saccharification and fermentation to deal with cellulose costly and effectively. Cellulose-degrading microbes were isolated from samples obtained from different environments and selected. 193 strains of cellulose-degrading microbes isolated from different environments were screened in this study. Trichoderma reesei ATCC26921 was found to be the most efficient cellulose-degrading microbe. By the use of T. reesei, a reducing sugars concentration (0.4070g/l) was obtained with a hydrolysis yield of 7.33% in culture condition of 30℃, 200rpm, initial pH6.0~7.0, and 96h. Unfortunately, the ethanol concentration was 0.1% only, when combine with Zymomonas mobilis ATCC29191 fermentation system. However, in the same culture condition, when supplementing the T. reesei with Aspergillus niger ATCC16888, we could increase the reducing sugars concentration up to 2.5708g/l and hydrolysis yield of 46.27%. The ethanol concentration was also increasing up to 4.24g/l when Z. mobilis fermentation system was added thereafter. Further development of the immobilized-cell system including the feasibility of using carrier and the optimum immobilization method were also investigated in this study. The preliminary results showed the microbe can be immobilized in the carrier completely with uniformly distribution. The total results showed high potential of ethanol production from agricultural waste in new co-culture system.