The influence of biochar (BC) on anerobic digestion (AD) of organic wastes have been widely studied. However, the effect of BC on rate-limiting step during AD of lignocellulosic waste, i.e. the hydrolysis and acidogenesis step, is rarely studied and the underlying mechanisms have not been investigated. In this study, the benefits of BC with respect to dark fermentative hydrogen production were explored in a fermentation system by a heat-shocked consortium from sewage sludge (SS) with pretreated sugarcane bagasse (PSCB) as carbon source. The results showed that biochar boosted biohydrogen production by 317.1% through stimulating bacterial growth, improving critical enzymatic activities, manipulating the ratio of NADH/NAD⁺ and enhancing electron transfer efficiency of fermentation system. Furthermore, cellulolytic Lachnospiraceae was efficiently enriched and electroactive bacteria were selectively colonized and the ecological niche was formed on the surface of biochar. Synergistic effect between functional bacteria and extracellular electron transfer (EET) in electroactive bacteria were assumed to be established and maintained by biochar amendment. This study shed light on the underlying mechanisms of improved performance of biohydrogen production from lignocellulosic waste during mesophilic dark fermentation by BC supplementation.

生物炭（BC）对有机废物厌氧消化（AD）的影响已得到广泛研究。然而，很少研究 BC 对木质纤维素废物 AD 过程中的限速步骤（即水解和酸化步骤）的影响，并且尚未研究其潜在机制。在这项研究中，BC 在发酵系统中探索了 BC 在暗发酵制氢方面的好处，该系统由来自污水污泥 (SS) 的热激财团以预处理的甘蔗渣 (PSCB) 作为碳源。结果表明，生物炭通过刺激细菌生长、提高关键酶活性、控制 NADH/NAD ⁺的比率，将生物氢产量提高了 317.1%提高发酵系统的电子转移效率。此外，纤维素分解毛螺菌科被有效富集，电活性细菌被选择性定殖，并在生物炭表面形成生态位。假设通过生物炭修正建立和维持功能细菌与电活性细菌中细胞外电子转移（EET）之间的协同效应。这项研究揭示了在通过 BC 补充进行的嗜温暗发酵过程中提高木质纤维素废物生产生物氢性能的潜在机制。