1株分离于铀矿的可利用玉米秸秆高效产氢的芽孢杆菌

Biohydrogen production by a newly strain of Bacillus isolated from uranium ore using cornstalk as feedstock

采用二重叠皿隔绝空气培养法从铀矿中分离获得1株可利用玉米秸秆高效产氢的菌株w-14,经生理生化及16S rRNA基因序列分析鉴定为丁酸梭菌(Clostridium butyricum);通过两段发酵技术,研究了用木霉、曲霉菌制备的纤维素酶麸曲酵解玉米秸秆的温度、时间、p H、麸曲用量对底物的糖化效率和w-14菌株利用玉米秸秆酵解物产氢的影响,结果表明:玉米秸秆酵解的麸曲浓度为20 g/L,温度为40℃、时间84 h,p H为5.0时酵解物还原糖为402 mg/g-cs,w-14菌株利用此酵解物发酵累积产氢量为99.7 m L/g-cs;采用正交试验优化出w-14菌株以玉米秸秆酵解物为碳源基质产氢发酵最适条件,并在5 L间歇搅拌深层发酵罐中完成验证,结果表明:初始p H 7.0,种龄16 h,接种量10%,发酵温度37℃,w-14菌株的产氢量达140.24 m L/g-cs,比优化前提高了41.38%。经5 L间歇搅拌深层发酵反应器验证,w-14菌株利用秸秆的最高累积产氢量达149.09 m L/g-cs,氢气浓度达到55.63%。

A newly bacterial strain w-14,efficiently transforming cornstalk to hydrogen,had been isolated from uranium ore samples with strictly anaerobic culturing method. It was finally nomenclatured as Clostridium butyricum on the basis of series of standard identification methods. The influences of glycolysis temperature,glycolysis time,glycolysis p H,bran koji concentration of Trichoderma koningii and Aspergillus bran koji e. t. c on the the substrate saccharification efficiency and hydrogen production by the strain w-14 were investigated. Two periods of fermentation were used to discuss the effect of glycolysis( glycolysis temperature,glycolysis time,glycolysis p H,bran koji concentration of Trichoderma koningii and Aspergillus bran koji) on the substrate saccharification efficiency and hydrogen production by the strain w-14. At the optimum of variables combination,such as 20 g / L of bran koji,an initial p H of 5. 0,incubating at 45 ℃ for 84 h by the Two stages of fermentation technology,the maximum reducing sugar content( 402 mg /g-cs) and cumulative H2 yield of 99. 7 m L / g-cs were obtained. Orthogonal design were used to optimize bio-hydrogen production from cornstalk glycolytic substrates by submerged fermentation. The maximum cumulative H2 yield of140. 24 m L / g-cs,increased by 41. 38%,was achieved at the optimized hydrogen production conditions from the assistance of orthogonal design. Furthermore,it demonstrated that maximum cumulative H2 and the hydrogen content could reach 140. 24 m L / g-cs,55. 63% respectively in 5 L batch fermentation tank.