海洋沉积物中铁还原细菌组成及异化铁还原与产氢性质分析

Composition of Fe(III)-reducing bacteria from marine sediments and characteristics of dissimilatory iron reduction coupled to hydrogen production

摘要:

【背景】一些铁还原细菌具有异化铁还原与产氢的能力，该类细菌在环境污染修复的同时能够解决能源问题。【目的】从海洋沉积物中富集获得异化铁还原菌群，明确混合菌群组成、异化铁还原及产氢性质。获得海洋沉积物中异化铁还原混合菌群组成，分析菌群异化铁还原和产氢性质。【方法】利用高通量测序技术分析异化铁还原菌群的优势菌组成，在此基础上，分析异化铁还原混合菌群在不同电子供体培养条件下异化铁还原能力和产氢性质。【结果】高通量数据表明，在不溶性氢氧化铁为电子受体和葡萄糖为电子供体厌氧培养条件下，混合菌群的优势菌属主要是梭菌(Clostridium)，属于发酵型异化铁还原细菌。混合菌群能够利用电子供体蔗糖、葡萄糖以及丙酮酸钠进行异化铁还原及发酵产氢。葡萄糖为电子供体时，菌群累积产生Fe(II)浓度和产氢量最高，分别是59.34±6.73 mg/L和629.70±11.42 mL/L。【结论】异化铁还原混合菌群同时具有异化铁还原和产氢能力，拓宽了发酵型异化铁还原细菌的种质资源，探索异化铁还原细菌在生物能源方面的应用。

Abstract:

[Background] Some anaerobic bacteria with simultaneous dissimilatory iron reduction and hydrogen production, belonging to fermentative dissimilatory Fe(III)-reducing bacteria, have been paid more and more attention for dual characteristics of energy-saving and environment-friendliness. [Objective] The composition of dissimilatory Fe(III) reduction mixed bacteria in marine sediments was obtained, and the characteristics of dissimilatory Fe(III) reduction and hydrogen production were analyzed. [Methods] The dominant population of Fe(III)-reducing mixed culture was obtained using high-throughput sequencing data, and on this basis the characteristics of microbial Fe(III) reduction coupled to hydrogen production were analyzed under the condition with six different electron donors. [Results] The result of high-throughput sequencing data showed that the dominant population was Clostridium, which was attributed to fermentative-type dissimilatory Fe(III)-reducing bacteria. The mixed culture could reduce Fe(III) and produce hydrogen using sucrose, glucose and sodium pyruvate as electron donor and iron hydroxide as electron acceptor. Among the six electron donors, glucose was the most effective electron donor for double characteristics with high microbial Fe(III) reduction and hydrogen production, with Fe(II) concentration of 59.34±6.73 mg/L and hydrogen production of 629.70±11.42 mL/L. [Conclusion] The results provide evidence for the application of dissimilatory Fe(III)-reducing bacteria for biological hydrogen production, which will widen the germplasm resource of fermentative-type dissimilatory Fe(III)-reducing bacteria.