Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università degli Studi di Foggia, Via Napoli 25, Foggia, Italy.
STAR Agroenergy Research Group, University of Foggia, Via Gramsci, 89-91, Foggia, Italy.
Appl Microbiol Biotechnol. 2016 Jan;100(1):493-504. doi: 10.1007/s00253-015-7002-6. Epub 2015 Oct 1.
To enhance the productivity of mixed microbial cultures for fermentative bio-hydrogen production, chemical-physical pre-treatments of the original seed are needed to suppress the activity of hydrogen (H2)-consuming microbes. This approach might influence negatively the composition and diversity of the hydrogen-producing community with consequences on the functional stability of the H2-producing systems in case of perturbations. In this study, we aimed at investigating the effect of different types of pre-treatment on the performance of hydrogen production systems in the presence of an inhibitor, such as 5-hydroxymethylfurfural (HMF). The efficiency and the microbial community structure of batch reactors amended with HMF and inoculated with non-pretreated and pretreated (acid, heat shock, and aeration) anaerobic sludge were evaluated and compared with control systems. The type of pre-treatments influenced the microbial community assembly and activity in inhibited systems, with significant effect on the performance. Cumulative H2 production tests showed that the pre-aerated systems (control and HMF inhibited) were the most efficient, while the difference of the lag phase of the pre-acidified control and HMF-added test was negligible. Analyses of the structure of the enriched microbial community in the systems through PCR-denaturing gradient gel electrophoresis (DGGE) followed by band sequencing revealed that the differences in performance were mostly related to shifts in the metabolic pathways rather than in the predominant species. In conclusion, the findings suggest that the use of specific inoculum pre-treatment could contribute to regulate the metabolic activity of the fermentative H2-producing bacteria in order to enhance the bio-energy production.
为了提高混合微生物培养物在发酵生物制氢中的生产力，需要对原始种子进行化学-物理预处理，以抑制氢（H2）消耗微生物的活性。这种方法可能会对产氢微生物群落的组成和多样性产生负面影响，从而对产氢系统的功能稳定性产生影响。在本研究中，我们旨在研究不同类型的预处理对存在抑制剂（如 5-羟甲基糠醛（HMF））时产氢系统性能的影响。评估并比较了添加 HMF 并接种未经预处理和预处理（酸、热冲击和曝气）厌氧污泥的批式反应器的效率和微生物群落结构与对照系统。预处理的类型影响了抑制系统中微生物群落的组装和活性，对性能有显著影响。累积产氢试验表明，预曝气系统（对照和 HMF 抑制）效率最高，而预酸化对照和 HMF 添加试验的滞后期差异可忽略不计。通过 PCR-变性梯度凝胶电泳（DGGE）对系统中富集微生物群落的结构进行分析，然后进行条带测序，结果表明，性能差异主要与代谢途径的变化有关，而不是与主要物种有关。总之，这些发现表明，使用特定的接种物预处理可以有助于调节发酵产氢细菌的代谢活性，从而提高生物能源的产量。
