Background Pretreatment of lignocellulosic biomass generates different types of inhibitors (e.g., furfural and acetic acid), which could remarkably inhibit subsequent ethanol fermentation. Here, biochar as an additive in the fermentation broth was first applied to enhance ethanol production by Z. mobilis wild-type strain ZM4 in the presence of typical inhibitors. Results This study showed that the biochar-mediated tolerance to furfural and acetic acid for the strain Z. mobilis ZM4 was the highest reported level, resulting in much higher ethanol productivity under stress conditions than that in non-treated conditions. Further analysis showed that adsorptive detoxification was not the controlling factor for enhanced ethanol production under stress conditions, attributed to its low removal of furfural (< 20%) and incapability of acetic acid removal. When biochar was filtered from the biochar-treated inhibitor-containing broth, it still showed enhanced ethanol production. Furthermore, Z. mobilis immobilized on biochar was also observed. Thus, biochar extracts in the fermentation broth and cell immobilization on biochar might be the controlling factors for enhanced ethanol production under stress conditions. Conclusions These results indicate that biochar-mediated enhanced ethanol fermentation (BMEEF) might be a promising strategy for ethanol production from lignocellulosic biomass.

中文翻译：

---

糠醛和乙酸胁迫下运动发酵单胞菌中生物炭介导的增强乙醇发酵（BMEEF）。


背景木质纤维素生物质的预处理会产生不同类型的抑制剂（例如糠醛和乙酸），它们可以显着抑制随后的乙醇发酵。在此，生物炭作为发酵液中的添加剂首次应用于在典型抑制剂存在下提高运动发酵单胞菌野生型菌株 ZM4 的乙醇产量。结果本研究表明，生物炭介导的运动发酵单胞菌ZM4菌株对糠醛和乙酸的耐受性是报道的最高水平，导致胁迫条件下的乙醇生产率比未处理条件下高得多。进一步分析表明，吸附解毒并不是胁迫条件下乙醇产量增加的控制因素，因为其糠醛去除率低（< 20%）且无法去除乙酸。当从生物炭处理的含有抑制剂的肉汤中过滤生物炭时，它仍然显示出增强的乙醇产量。此外，还观察到固定在生物炭上的运动发酵单胞菌。因此，发酵液中的生物炭提取物和生物炭上的细胞固定可能是胁迫条件下增强乙醇产量的控制因素。结论 这些结果表明生物炭介导的强化乙醇发酵（BMEEF）可能是从木质纤维素生物质生产乙醇的一种有前途的策略。