文摘
Preconditioning of lignocellulosic biomass unfortunately leads to the formation of degradation byproducts that severely inhibit the subsequent enzymatic hydrolysis. This study attempts to prioritize these degradation compounds such that a basis for their mitigation can be developed. Rice straw prehydrolyzates, produced by hot water pretreatment at 220 °C and 52 min, were fractionated using centrifugal partition chromatography (CPC) into phenolics, furans, organic acids, monomeric and oligomeric sugars. Purified inhibitors were tested against substrate conversion efficiencies of exo-cellulase enzyme from Hypocrea jecorina. Results showed that rice straw phenolics at 1 g/L reduced the specific hydrolysis rate by 92% compared to that of control. It was followed by acetic acid, which reduced enzyme efficiency by 87% at 1 g/L. The CPC purified xylo-oligosaccharides only inhibited the initial substrate hydrolysis rate of exo-cellulase, that which recovered over time and was comparable to that of the control after 150 min of incubation.