厌氧发酵产氢细菌的分离和鉴定及产氢特性

获得优良的产氢菌株,鉴定并研究其产氢特性,为提高其产氢能力提供基础。对样品进行预处理和葡萄糖梯度驯化处理后,采用厌氧培养技术分离单菌落,进行菌株形态学观察、生理生化试验及16S rDNA分子生物学鉴定,并采用分批式厌氧发酵研究其产氢特性。结果表明:其中产氢最优的菌株FML-C1为肠杆菌属细菌,葡萄糖为其产氢的最优碳源,氮源则以酵母粉和蛋白胨混合最佳,最适生长和产氢温度为35℃,最佳初始pH值为6.0,该条件下菌株的气相末端产物中氢体积分数达56.51%。菌株FML-C1为一株良好的厌氧发酵产氢菌,可进一步优化其产氢工艺,以提高其产氢能力。     

L-半胱氨酸浓度对氧化还原电位和生物产氢过程的影响(英文)

The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,hydrogen production rate and hydrogen yield when its concentration was less than 500 mg·L-1,while it had negative effects when its concentration was higher than 500 mg·L-1.The hydrogen production was the highest 1.29 mol·mol-1(H2/glucose) when 300 mg·L-1L-cysteine was added into the culture,and the yield was 9.4% higher than that in the control.The oxidation-reduction potential(ORP) ,which was influenced by L-cysteine,also affected hydrogen production.The ORP values were in the range-300 mV to-150 mV when the L-cysteine concentration was higher than 500 mg·L-1.Although the ORP in this range was favorable for hydrogen production,it was not suitable for the biomass growth.Hence,less hydrogen was produced.When the L-cysteine concentration was lower than 500 mg·L-1,the ORP was more suitable for both biomass growth and hydrogen production.In addition,at least 91%glucose was consumed when L-cysteine was added to the culture media,compared to the 97.37% consumption without L-cysteine added.