This study investigated softwood hemicelluloses degradation pathways during alkaline hydrogen peroxide (AHP) pretreatment of Douglas fir. It was found that glucomannan is much more susceptible to alkaline pretreatment than xylan. Organic acids, including lactic, succinic, glycolic and formic acid are the predominant products from glucomannan degradation. At low treatment temperature (90°C), a small amount of formic acid is produced from glucomannan, whereas glucomannan degradation to lactic acid and succinic acid becomes the main reactions at 140°C and 180°C. The addition of H2O2 during alkaline pretreatment of D. fir led to a significant removal of lignin, which subsequently facilitated glucomannan solubilization. However, H2O2 has little direct effect on the glucomannan degradation reaction. The main degradation pathways involved in glucomannan conversion to organics acids are elucidated. The results from this study demonstrate the potential to optimize pretreatment conditions to maximize the value of biomass hemicellulose.

中文翻译：

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碱性过氧化氢软木预处理：半纤维素降解途径。

这项研究调查了道格拉斯冷杉的碱性过氧化氢（AHP）预处理期间软木半纤维素的降解途径。发现葡甘露聚糖比木聚糖更易受碱性预处理。有机酸，包括乳酸，琥珀酸，乙醇酸和甲酸是葡甘露聚糖降解的主要产物。在较低的处理温度（90°C）下，葡甘露聚糖产生少量甲酸，而葡甘露聚糖降解为乳酸和琥珀酸则成为140°C和180°C的主要反应。在杉木的碱性预处理过程中加入H2O2导致木质素的大量去除，随后促进了葡甘露聚糖的增溶作用。然而，H 2 O 2对葡甘露聚糖降解反应几乎没有直接影响。阐明了葡甘露聚糖转化为有机酸的主要降解途径。这项研究的结果证明了优化预处理条件以最大化生物质半纤维素价值的潜力。