Acetate and p-coumaric acid, which inhibit fermentation, are important byproducts from the sugarcane biomass pretreatment and hydrolysis steps. At the same time, organic and phenolic acids are valuable substrates to produce bioelectricity in Microbial Fuel Cells (MFCs). Here, we operated an MFC with a synthetic non-fermentable fraction of sugarcane biomass hydrolysates; we employed acetate spiked with p-coumaric acid as substrates. At maximum activity of the bacterial community, the potential and power density of the MFC fed with acetate alone reached 0.47 V and 478 mW m⁻², respectively; upon addition of 0.1 mM p-coumaric acid, these values decreased to 0.34 V and 398 mW m⁻², respectively. p-Coumaric acid at 0.1 mM was efficiently metabolized (79 %) in the MFC by a minimalist, but robust bacterial community composed mainly of Pseudomonas spp. and Pseudochrobactrum spp. Our work suggests that p-coumaric acid can be applied to generate energy, adding value to a non-fermentable fraction obtained in the sugarcane biorefinery.

乙酸和对香豆酸会抑制发酵，它们是甘蔗生物质预处理和水解步骤的重要副产物。同时，有机酸和酚酸是微生物燃料电池 (MFC) 中产生生物电的宝贵底物。在这里，我们使用合成的不可发酵甘蔗生物质水解物部分操作 MFC；我们使用掺有对香豆酸的醋酸盐作为底物。在细菌群落的最大活性下，单独加入醋酸盐的 MFC 的电位和功率密度分别达到 0.47 V 和 478 mW m ^-2；添加 0.1 mM对香豆酸后，这些值分别降低至 0.34 V 和 398 mW m ^-2。p-0.1 mM 的香豆酸在 MFC 中被一个极简但强大的细菌群落有效代谢 (79%)，主要由假单胞菌属组成。和Pseudochrobactrum spp。我们的工作表明，对香豆酸可用于产生能量，为甘蔗生物精炼厂中获得的不可发酵部分增加价值。