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以高温厌氧细菌热纤维梭菌(Clostridium thermocellum LQRI)和嗜热厌氧乙醇菌(Thermoanaerobacter ethanolicus X514和Thermoanaerobacter pseudoethanolicus39E)为对象,以纤维素为微生物利用的底物,分析了LQRI纯培养和LQRI+Thermoanaerobacter混合培养对纤维素降解、酒精生产及终产物分布的影响.结果表明,LQRI+Thermoanaerobacter混合培养的酒精生产能力和纤维素降解率明显高于LQRI纯培养.在混合培养体系中,LQRI+X514的酒精生产能力明显高于LQRI+39E.培养基中无外源酵母粉条件下,LQRI纯培养酒精最高浓度约为11.5mmol/L,LQRI+X514和LQRI+39E混合培养最高酒精浓度分别约为71mmol/L和36.5mmol/L,相同的底物纤维素浓度条件LQRI+X514和LQRI+39E混合培养酒精浓度分别约为LQRI纯培养的5～11倍和3～5倍,纤维素降解率分别都约为LQRI纯培养的1.5～5.0倍;培养基中0.6%外源酵母粉存在条件下,LQRI纯培养酒精最高浓度约为12.9mmol/L,LQRI+X514和LQRI+39E混合培养最高酒精浓度分别约为263.5mmol/L和143.5mmol/L,相同的底物纤维素浓度条件LQRI+X514和LQRI+39E混合培养酒精浓度分别约为LQRI纯培养的8～22倍和8～12倍,纤维素降解率均约为LQRI纯培养的1.1倍.在5%Solka Floc为底物和0.6%外源酵母粉的条件下,LQRI+X514混合培养酒精浓度最高可达到263.5mmol/L,相当于1.2%(质量浓度)的酒精,LQRI+39E约为143mmol/L.
Clostridium thermocellum LQRI and Thermoanaerobacter ethanolicus X514 and Thermoanaerobacter pseudoethanolicus39E were used as substrates to investigate the effects of LQRI pure culture and LQRI + Thermoanaerobacter mixed culture on cellulose degradation, alcohol production and final product distribution.The results showed that LQRI + Thermoanaerobacter mixed culture ethanol production ability and cellulose degradation rate was significantly higher than LQRI pure culture.In the mixed culture system, LQRI + X514 Alcohol production ability was significantly higher than that of LQRI + 39E.The maximum concentration of pure LQRI alcohol was about 11.5mmol / L under the condition of no exogenous yeast powder in the medium, and the highest alcohol concentration of LQRI + X514 and LQRI + 39E mixed culture was about 71mmol / L and 36.5mmol / L, respectively. Under the same conditions of substrate cellulose concentration, the mixed culture alcohol concentrations of LQRI + X514 and LQRI + 39E were about 5 ~ 11 times and 3 ~ 5 times higher than that of pure LQRI culture respectively. The results showed that the highest concentration of pure LQRI cultured alcohol was about 12.9 mmol / L in the presence of 0.6% exogenous yeast extract in the medium, LQRI + X514 And LQRI + 39E were about 263.5mmol / L and 143.5mmol / L, respectively. Under the same substrate concentration of cellulose, the concentrations of LQRI + X514 and LQRI + 39E mixed culture were about 8 ~ 22 times and 8 ~ 12 times, cellulose degradation rates were about 1.1 times the pure LQRI culture in 5% Solka Floc substrate and 0.6% exogenous yeast powder conditions, LQRI + X514 mixed culture of the highest alcohol concentration Reached 263.5 mmol / L, corresponding to 1.2% (mass concentration) of alcohol, LQRI + 39E was about 143 mmol / L.