Abstract:
Lignin deposits formed on the surface of pretreated lignocellulosic substrates during acidic pretreatments can non-productively adsorb costly enzymes and thereby influence the enzymatic hydrolysis efficiency of cellulose. In this article, peanut protein (PP), a biocompatible non-catalytic protein, was separated from defatted peanut flour (DPF) as a lignin blocking additive to overcome this adverse effect. With the addition of 2.5 g/L PP in enzymatic hydrolysis medium, the glucose yield of the bamboo substrate pretreated by phenylsulfonic acid (PSA) significantly increased from 38 to 94% at a low cellulase loading of 5 FPU/g glucan while achieving a similar glucose yield required a cellulase loading of 17.5 FPU/g glucan without PP addition. Similar promotion effects were also observed on the n-pentanol-pretreated bamboo and PSA-pretreated eucalyptus substrates. The promoting effect of PP on enzymatic hydrolysis was ascribed to blocking lignin deposits via hydrophobic and/or hydrogen-bonding interactions, which significantly reduced the non-productive adsorption of cellulase onto PSA lignin. Meanwhile, PP extraction also facilitated the utilization of residual DPF as the adhesive for producing plywood as compared to that without protein pre-extraction. This scheme provides a sustainable and viable way to improve the value of woody and agriculture biomass. Peanut protein, a biocompatible non-catalytic protein, can block lignin, improve enzymatic hydrolysis efficiency and thereby facilitate the economics of biorefinery.
摘要:
在酸性预处理过程中,在预处理的木质纤维素基材表面上形成的木质素沉积物可能会非生产性地吸附昂贵的酶,从而影响纤维素的酶促水解效率。在这篇文章中,花生蛋白(PP),一种生物相容的非催化蛋白质,与脱脂花生粉(DPF)分离作为木质素阻断添加剂以克服这种不利影响。在酶解介质中添加2.5g/LPP,在5FPU/g葡聚糖的低纤维素酶载量下,经苯基磺酸(PSA)预处理的竹底物的葡萄糖产率从38%显著增加至94%,同时实现相似的葡萄糖产率需要17.5FPU/g葡聚糖的纤维素酶载量而不添加PP。在正戊醇预处理的竹子和PSA预处理的桉树基质上也观察到类似的促进作用。PP对酶促水解的促进作用归因于通过疏水和/或氢键相互作用阻断木质素沉积物。这显著降低了纤维素酶在PSA木质素上的非生产性吸附。同时,与没有蛋白质预提取的情况相比,PP提取还有助于将残留的DPF用作生产胶合板的粘合剂。该方案为提高木本和农业生物质的价值提供了可持续和可行的方法。花生蛋白,一种生物相容的非催化蛋白质,可以阻断木质素,提高酶水解效率,从而促进生物炼制的经济性。