A sequential co-culture approach of cellulosome producing Clostridium thermocellum ATCC 27405 and solventogenic Clostridium beijerinckii NCIMB 8052 was investigated for directly converting lignocellulosic substrates to butanol under anaerobic condition. C. thermocellum was cultured on the medium containing 50 g⋅L−1 corncob at 60℃. By maintaining different pH in the different stages of fermentation and periodically supplying 55 g⋅L−1 corncob at exponential growth phase, 94.3 g⋅L−1 corncob was efficiently degraded and 37.4 g⋅L−1 reducing sugar accumulation was typically obtained in acid-hydrolyzed supernatant for 120 h. In the reducing sugar accumulation, the concentration of pentose and glucose are 24.8 g⋅L−1 and 5.28 g⋅L−1, respectively. Co-culture of C. thermocellum and C. beijerinckii results in the efficient utilization of corncob. The yield of ABE (acetone, butanol and ethanol) is 16.0 g⋅L−1, in which butanol is 8.75 g⋅L−1. The result shows that the sequential co-culture of C. thermocellum and C. beijerinckii offers the potential of lowering biofuel production costs due to the lack of cellulase cost and the effective simultaneous fermentation of hexose and pentose.% 通过纤维小体产生菌Clostridium thermocellum ATCC 27405与产溶剂菌Clostridium beijerinckii NCIMB 8052的偶联培养，直接从木质纤维原料厌氧发酵生产丁醇。首先考察C. thermocellum在60℃下对玉米棒芯的降解情况，初始玉米棒芯浓度为50 g⋅L−1。分阶段控制发酵pH，并在指数生长期内间歇补给55 g⋅L−1玉米棒芯，C. thermocellum 120 h内降解94.3 g⋅L−1玉米棒芯，发酵上清液经稀硫酸水解后，测得总还原糖含量为37.4 g⋅L−1，其中戊糖含量24.8 g⋅L−1，葡萄糖含量5.28 g⋅L−1。进一步研究C. thermocellum和C. beijerinckii偶联发酵，利用玉米棒芯生产总溶剂(丙酮、丁醇、乙醇)浓度达16.0 g⋅L−1，其中丁醇产量高达8.75 g⋅L−1。研究结果表明：该偶联发酵体系无须添加外源纤维素酶，并能同时发酵己糖和戊糖，具有实现生物燃料低成本生产的潜力。
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