초록
<P><B>Abstract</B></P> <P>One of the main challenges of second generation (2G) ethanol production is the high quantities of phenolic compounds and furan derivatives generated in the pretreatment of the lignocellulosic biomass, which inhibit the enzymatic hydrolysis and fermentation steps. Fast monitoring of these inhibitory compounds could provide better control of the pretreatment, hydrolysis, and fermentation processes by enabling the implementation of strategic process control actions. We investigated the feasibility of monitoring these inhibitory compounds by ultraviolet–visible (UV–Vis) spectroscopy associated with partial least squares (PLS) regression. Hydroxymethylfurfural, furfural, vanillin, and ferulic and p-coumaric acids generated during different severities of liquid hot water pretreatment of sugarcane bagasse were quantified with highly accuracy. In cross-validation (leave-one-out), the PLS-UV–Vis method presented root mean square error of prediction (RMSECV) of around only 5.0%. The results demonstrated that the monitoring performance achieved with PLS-UV–Vis could support future studies of optimization and control protocols for application in industrial processes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Inhibitors from biomass pretreatment hinder the biochemical reactions. </LI> <LI> Rapid monitoring of inhibitors is essential in the 2G ethanol production. </LI> <LI> High accuracy quantification of furaldehydes and phenolic compounds by PLS-UV–Vis. </LI> <LI> PLS-UV–Vis supports optimization and control protocols for biorefineries. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>