This study investigated the impact of humic acid (HA) on enzymatic pretreatment efficiency, focusing on sludge properties and HA molecular structure. The results showed that enzymatic pretreatment alleviates HA inhibition, improving hydrolysis efficiency. In the presence of HA, soluble proteins and polysaccharides in the enzyme-cocktail group reached 27.7 mg/L and 23.9 mg/L, 1.4 and 1.3 times higher than the blank group, respectively. The enzyme-cocktail group also had the highest soluble DNA concentration (19.4 mg/L) and the lowest viable cell proportion (69.3 %), indicating effective cell lysis. Enzyme-cocktail pretreatment reduced electrostatic repulsion, enhancing the mobility of extracellular organics. Enzyme interactions with HA released internal hydrolases and decreased amide groups on the HA surface, increasing the availability of biodegradable substrates. Overall, enzymatic pretreatment proves effective in mitigating HA-induced inhibition, thereby improving sludge biodegradation and enhancing carbon recovery in anaerobic fermentation.

中文翻译：

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酶溶菌酶联合预处理对腐植酸抑制下污泥有机物水解效果的研究


本研究调查了腐植酸 （HA） 对酶前处理效率的影响，重点关注污泥性质和 HA 分子结构。结果表明，酶前处理减轻了 HA 抑制，提高了水解效率。在 HA 存在下，酶-鸡尾酒组的可溶性蛋白和多糖分别达到 27.7 mg/L 和 23.9 mg/L，分别是空白组的 1.4 和 1.3 倍。酶混合物组的可溶性 DNA 浓度最高 （19.4 mg/L） 和活细胞比例最低 （69.3 %），表明细胞裂解有效。酶混合物预处理减少了静电排斥，增强了细胞外有机物的流动性。酶与 HA 的相互作用释放了内部水解酶并减少了 HA 表面的酰胺基团，从而增加了可生物降解底物的可用性。总体而言，酶预处理被证明可有效减轻 HA 诱导的抑制，从而改善污泥生物降解并增强厌氧发酵中的碳回收率。