After several rounds of milling process for sugars extraction from sugarcane, certain amounts of water-soluble carbohydrates (WSC) still remain in sugarcane bagasse. It is a bottleneck to utilize WSC in sugarcane bagasse biorefinery, since these sugars are easily degraded into inhibitors during pretreatment. Herein, a simple pre-fermentation step before pretreatment was conducted, and 98 % of WSC in bagasse was fermented into d-lactic acid. The obtained d-lactic acid was stably preserved in bagasse and 5-hydroxymethylfurfural (HMF) generation was sharply reduced from 46.0 mg/g to 6.2 mg/g of dry bagasse, after dilute acid pretreatment. Consequently, a higher d-lactic acid titer (57.0 g/L vs 33.2 g/L) was achieved from the whole slurry of the undetoxified and pretreated sugarcane bagasse by one-pot simultaneous saccharification and co-fermentation (SSCF), with the overall yield of 0.58 g/g dry bagasse. This study gave an efficient strategy for enhancing lactic acid production using the lignocellulosic waste from sugar industry.

从甘蔗中提取糖分经过几轮碾磨过程后，一定量的水溶性碳水化合物 (WSC) 仍残留在甘蔗渣中。在甘蔗渣生物精炼中利用WSC是一个瓶颈，因为这些糖在预处理过程中很容易降解成抑制剂。在此，在预处理前进行简单的预发酵步骤，将甘蔗渣中98%的WSC发酵成d-乳酸。经过稀酸预处理后，所获得的d-乳酸在甘蔗渣中稳定保存，5-羟甲基糠醛 (HMF) 的生成量从干甘蔗渣的 46.0 mg/g 急剧减少至 6.2 mg/g。因此，更高的d-通过一锅同步糖化和共发酵（SSCF）从未脱毒和预处理的甘蔗渣全浆中获得乳酸效价（57.0 g/L vs 33.2 g/L），总产量为0.58 g/ g 干甘蔗渣。该研究提供了一种利用制糖工业的木质纤维素废料提高乳酸产量的有效策略。