Steam pretreatment is an effective approach to open up the intact lignocellulosic matrix for biofuels and animal feed production. However, crop residues especially corn stover contain certain amounts of water-soluble carbohydrates (WSC), which are easily degraded into toxic 5-hydroxymethylfurfural (HMF) at high temperature and bring negative effects on subsequent utilization of lignocellulose biomass. Few studies have focused on the WSC loss and proposed a corresponding solution to utilize them in steam pretreatment. This study introduced a solid-state fermentation prior to steam pretreatment of corn stover to convert WSC into lactic acid, which could catalyze the hydrolysis of hemicellulose and acetyl groups in pretreatment. Compared to the regular steam pretreatment at the same severity (180 °C for 5 min), the conversion yields of xylan and arabinan in the steam pretreatment were both increased from 9.6% and 37.2% to 28.8% and 69.6%, respectively. Cellulose conversion also increased from 48.1% to 50.7% in the subsequent enzymatic hydrolysis. On the other hand, the generation of the toxic HMF reduced by 42.1% due to the pre-conversion of WSC into the relatively thermal stable lactic acid. This study provided an effective approach to process corn stover with higher hydrolysis yield and lower inhibitor generation.

蒸汽预处理是打开完整的木质纤维素基质用于生物燃料和动物饲料生产的有效方法。但是，农作物残留物，特别是玉米秸秆，含有一定量的水溶性碳水化合物（WSC），在高温下容易降解为有毒的5-羟甲基糠醛（HMF），并对木质纤维素生物质的后续利用带来负面影响。很少有研究关注WSC的损失，并提出了相应的解决方案来将其用于蒸汽预处理。这项研究在玉米秸秆的蒸汽预处理之前进行了固态发酵，以将WSC转化为乳酸，这可以催化预处理中的半纤维素和乙酰基水解。与相同强度（180°C 5分钟）的常规蒸汽预处理相比，蒸汽预处理中木聚糖和阿拉伯聚糖的转化率分别从9.6％和37.2％分别提高到28.8％和69.6％。在随后的酶水解中，纤维素转化率也从48.1％增加到50.7％。另一方面，由于WSC预先转化为相对热稳定的乳酸，有毒HMF的生成量减少了42.1％。这项研究提供了一种有效的方法来加工玉米秸秆，具有较高的水解产量和较低的抑制剂生成量。1％是由于WSC预先转化为相对热稳定的乳酸。这项研究提供了一种有效的方法来加工玉米秸秆，具有较高的水解产量和较低的抑制剂生成量。1％是由于WSC预先转化为相对热稳定的乳酸。这项研究提供了一种有效的方法来加工玉米秸秆，具有较高的水解产量和较低的抑制剂生成量。