Cell wall-associated transition metals improve alkaline-oxidative pretreatment in diverse hardwoods

摘要: The responses of four diverse hardwoods (hybrid poplar, silver birch, hybrid aspen, and sugar maple) to alkaline hydrogen peroxide (AHP) pretreated at ambient temperature pressure were analyzed gain a deeper understanding the cell wall properties that contribute differences in enzymatic hydrolysis efficacy following alkaline-oxidative pretreatment. yields these increased significantly with increasing wall-associated, redox-active transition metal content. These increases directly correlated improved delignification. Furthermore, we demonstrated improvements could be achieved either through elevated levels naturally-occurring metals, namely Cu, Fe, Mn, or by addition homogeneous catalyst (e.g. Cu 2,2′-bipyridine complexes) capable penetrating into matrix. Removal wall-associated metals chelation resulted substantial decreases AHP pretreatment, while re-addition form complexes limited extent Fe prior pretreatment restored yields. Glycome profiles showed extractability xylan, xyloglucan, pectin epitopes for subjected demonstrating strength association between matrix polymers decreased as consequence