Structural and Functional Characterization of TwoPennisetumsp. Biomass during Ultrasono-Assisted Alkali Pretreatment and Enzymatic Hydrolysis for Understanding the Mechanism of Targeted Delignification and Enhanced Saccharification

Abstract

The recalcitrance offered by lignocellulose to get converted into simple sugars makes its conversion process complicated, hence pretreatment is required prior to enzymatic hydrolysis and fermentation. Ultrasonication-assisted alkali pretreatment (UA-NaOH) was found to be an effective pretreatment for delignification and enzymatic hydrolysis of denanath grass (DG) and hybrid napier grasses (HNG) in terms of maximum delignification and reducing sugar production. To determine the mechanism of pretreatment and enzymatic hydrolysis, the structural and functional characterization of native and pretreated grass biomass were investigated using SEM (scanning electron microscope), FT-IR (Fourier transformation infrared) spectroscopy, TGA (thermal gravimetric analysis), DSC (differential scanning) spectroscopy, and solid state 13C CP/MAS NMR (cross-polarization magic angle spinning nuclear magnetic resonance) spectroscopy. The surface erosions, distorted surface morphology and deconstruction of the cell wall compone...