Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden.
Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden.
Bioresour Technol. 2018 Jan;247:200-208. doi: 10.1016/j.biortech.2017.09.081. Epub 2017 Sep 14.
Hydrothermal pretreatment improves bioconversion of lignocellulose, but the effects of different acid catalysts are poorly understood. The effects of sulfuric acid (SA) and sulfur dioxide (SD) in continuous steam pretreatment of wood of Norway spruce were compared in the temperature range 195°C-215°C. The inhibitory effects of the pretreatment liquid on cellulolytic enzymes and Saccharomyces cerevisiae yeast were higher for SD- than for SA-pretreated material, and the inhibitory effects increased with increasing pretreatment temperature. However, the susceptibility to cellulolytic enzymes of wood pretreated with SD was 2.0-2.9 times higher than that of wood pretreated with SA at the same temperature. Data conclusively show that the superior convertibility of SD-pretreated material was not due to inhibition phenomena but rather to the greater capability of the SD pretreatment to reduce the particle size through partial delignification and cellulose degradation. Particle size was shown to be correlated with enzymatic digestibility (R 0.97-0.98).
水热预处理可以提高木质纤维素的生物转化效率，但不同酸催化剂的作用效果还不太清楚。在 195°C-215°C 的温度范围内，比较了硫酸（SA）和二氧化硫（SD）在连续蒸汽预处理挪威云杉木材中的作用。预处理液对纤维素酶和酿酒酵母的抑制作用在 SD 预处理材料中比在 SA 预处理材料中更高，并且随着预处理温度的升高而增加。然而，在相同温度下，用 SD 预处理的木材对纤维素酶的敏感性比用 SA 预处理的木材高 2.0-2.9 倍。数据明确表明，SD 预处理材料具有更高的转化率并非由于抑制现象，而是由于 SD 预处理通过部分脱木质素和纤维素降解来减小颗粒尺寸的能力更强。颗粒尺寸与酶解度呈显著相关（R 0.97-0.98）。
