经胆碱氨基酸水溶液预处理的水稻秸秆中残余木质素对多糖酶水解抑制作用的研究

The Influence of Lignin on Enzymatic Hydrolysis of Polysaccharides from Rice Straw Pretreated with [Ch] [AA]-water

摘要:

本文通过考察牛血清蛋白（BSA）的添加量和不同纤维素酶用量下其添加与否对水稻秸秆残渣中多糖酶水解效率的影响，以及比较不同木质素含量的底物对纤维素酶催化行为的影响来探讨[胆碱][氨基酸]处理水稻秸秆残渣后其残留木质素对纤维素酶活性的抑制作用大小。结果发现，低酶量下，BSA的添加对纤维素和半纤维素的酶水解降解度有轻微的促进作用，分别最多提高5%及7%；而高纤维素酶用量时，其促进作用甚微。且经该类离子液体处理后的不同木质素含量的水稻秸秆基本上对酶蛋白皆无显著吸附和抑制作用。可见，该类离子液体可去除部分木质素以提高酶分子对多糖底物的可及性，此为多糖酶水解效率提高的关键因素，而该法所形成的残余木质素对酶蛋白的非特异吸附或抑制作用相对较弱。

Abstract:

The effect of bovine serum albumin (BSA) addition on the enzymatic hydrolysis of rice straw residues containing different lignin content obtained by different [Ch][AA] ILs-water mixture pretreatment were investigated. The results showed that a slight increase in cellulose and xylan digestibility occurred under low enzyme loading after BSA pre-incubation; the maximum digestibility was increased by 5% and 7% BSA, respectively. However, there was no clear enhancement in cellulose and xylan digestibility with high enzyme loading. This study also found that the rice straw lignin content did not affect enzyme adsorption when pretreated with different [Ch] [AA] ILs-water mixtures. Overall, the results indicate that it is polysaccharide accessibility to enzymes rather than lignin adsorption and inhibition of enzymes that mainly determines the efficiency of enzymatic degradation of polysaccharides in the rice straw residues obtained by [Ch][AA] ILs-water mixture pretreatment.