高效产氢菌株Enterococcus sp. LG1的分离及产氢特性

Isolation and Characterization of a New High Efficient H2-producing Bacterium Enterococcus sp. LG1

摘要:

采用Hungate厌氧培养技术分别从厌氧污泥、好氧污泥及河底泥中分离出12株厌氧产氢细菌, 并对其中的Enterococcus sp. LG1(注册号: EU258743)进行了研究。结果表明, 该株细菌为专性厌氧菌, 经革兰氏染色结果为阴性。通过16S rDNA 碱基测序和比对证实, 该菌株是目前尚未报道过的1个新菌种, 初步确定其细菌学上的分类地位。同时, 以灭菌预处理的污泥为底物培养基, 对该菌的产氢能力及污泥发酵过程中底物性质变化(SCOD、可溶性蛋白质、总糖和pH值等)进行了探讨。实验结果显示, 产氢菌Enterococcus sp. LG1的发酵过程中只有H2和CO2产生, 无CH4产生。产气量最高为36.48 mL/g TCOD, 氢气含量高达73.5%, 为已报道文献中以污泥为底物发酵制氢中之最高。根据污泥发酵产物分析得知, 该菌的发酵类行为典型的丁酸型发酵。

Abstract:

12 strains of H2-producing bacteria were isolated and purified from anaerobic sludge, aerobic sludge and river bottom sludge by Hungate method. A new species of high efficient hydrogen production bacterium Enterococcus sp. LG1 (registration number: EU258743 ) was studied deeply. It was showed that the Enterococcus sp. LG1 was an anaerobic and Gram-negative bacterium. Sequence analysis of this type of clones showed that it was affiliated with the genus Enterococcus and it was not reported yet in other paper at present. Meanwhile, batch tests of anaerobic fermentative hydrogen production by Enterococcus sp. LG1 were investigated by using sterilization pretreated sludge as substrate. The changes of soluble COD, protein, carbohydrate and pH value during hydrogen fermentation were monitored. It was found that only hydrogen and carbon dioxide were produced by this strain and no methane was detected during fermentation. The maximal hydrogen yield was 36.48 mL/g TCOD and the hydrogen concentration in the gas phase was 73.5%. The Enterococcus sp. LG1 was a butyrate fermentation bacteria analyzed by metabolites.