纖維素可提供大量生質能的來源。本研究由東海大學牧場飼養的乳牛所排放出之糞便中，培養出能降解纖維素產生乙醇的嗜熱厭氧穩定菌群。研究菌群以濾紙(Whatman NO.1)為纖維素基質，由GC-FID分析乙醇產量，其最佳乙醇生成溫度及pH值分別為55-60℃左右及pH 7.7；增加氮源(yeast extract, peptone)濃度至培養基內的最佳乙醇產率之添加濃度均為1g/l；最佳產乙醇率之濾紙濃度為8g/l；降解不同紙類產生乙醇能力為濾紙>影印紙>卡紙>報紙（無法被降解）。培養基內濾紙(10g/l)可於九天內被研究菌群完全降解，其最終乙醇的產率約為0.29g ethanol/g cellulose。 本研究藉由分子生物技術，以巢式聚合?鏈反應－變性梯度電泳凝膠法(Nested PCR-DGGE)分析此菌群16S rDNA中V3-V5的變異區段，利用亮帶擷取，再由PCR擴增萃取核酸片段後，進行定序分析菌群結構及親緣關係。在本研究中發現馴養之後的牛糞菌群之16S rDNA核酸片段與梭菌目(Clostridiales)及嗜厭氧桿菌目(Thermoanaerobacteriales)有接近之親緣關係。 Cellulose can be a major source of biomass energy. Thermophilic anaerobic biodegradation of cellulose by mixed microbial community from dairy cattle manure in Tunghai University range is demonstrated in this study. The pure cellulose (Whatman NO.1 filter paper) is used as the carbon source for producing ethanol by the mixed microbial community. GC-FID is used to analyze ethanol production from cellulose degradation. The optimal ethanol production temperature of the mixed thermophilic anaerobes is 55-60℃. The optimal ethanol production pH of the mixed thermophilic anaerobes is 7.7. Ethanol production can be increased in the mixed culture by adding 1g/l of yeast extract and peptone respectively as nitrogen sources. The optimal substrate concentration for ethanol production is 8g/l filter paper. Various used papers (filter paper, office paper, newspaper and cardboard) were used in this study to test their potential for ethanol production. The result showed the potential of tested used paper for ethanol production by this mixed culture is filter paper > office paper > cardboard > newspaper by the mixed microbial community in this study. The mixed microbial community of this study can completely degrade 10g/l of filter paper in 9 days, during which the ethanol yield is 0.29g ethanol/g cellulose. Phylogenetic and sequence similarity of the variable region (V3-V5) of 16S rDNA from the mixed thermophilic anaerobes is analyzed for their revolutionary relationship by using Nested PCR-denaturing gradient gel electrophoresis (Nested PCR-DGGE) technology. Clostridiales and Thermoanaerobacteriales are the two closest predominant groups in this thermophilic, anaerobic community.
