Relationship to reducing sugar production and scanning electron microscope structure to pretreated hemp hurd biomass (Cannabis sativa)

Lignocellulosic biomass is a highly rigid and recalcitrant structure which requires pretreatment to loosen chemical bonds to make accessible monomeric sugars for biofuel production. In this study, locally available biomass, that is hemp (Cannabis sativa), a low cost feedstock for ethanol production, has been used for the production of fermentable sugars. Hemp hurd biomass (HHB) was exposed to five different pretreatments which included dilute acid (H2SO4), alkaline (NaOH), alkaline peroxide, hot water and one stage dilute acid (H2SO4). Different pretreatments resulted in loosening and degradation of HHB structure thus facilitating enzymatic saccharification at optimized parameters (pH–4.8 and 50 °C). The changes in the reactive groups (hydroxyl or acetyl) of the HHB were confirmed by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Scanning electron microscopy (SEM) was employed to characterize the surface morphology of untreated and treated HHB. Finally, enzymatic saccharification demonstrated maximum yield of total sugars (743 mg g−1) that are suitable for biofuel production.