The effect of assorted pretreatments on cellulose of selected vegetable waste and enzymatic hydrolysis

Pretreatment of biomass for the production of biofuels and value added products involves physical disruption of the polymeric linkages of lignocellulosic material which enhances the accessibility of lignocellulases and removes lignin. To investigate the impact of assorted pretreatments on structural changes, low lignin containing vegetable waste was selected as the biomass source. The combined effects of NaCl under different physical conditions on the biomass material were evaluated. Amounts of soluble sugars, monomeric phenols, holocellulose, inhibitors of hydrolysis and fermentation formed were determined. Physical and microstructural alterations of the material were analysed by XRD, FTIR and SEM. Accessibility of enzymes to the cellulose material was evaluated by quantifying the release of sugars in enzymatic hydrolysis for various pretreatment methods. The data revealed that pretreatment with NaCl is cost effective, ecofriendly and the process efficiency is comparable with common pretreatment methods like alkali, acid, ammonia, super critical fluid extraction etc. This is the first report on the use of sodium chloride for the pretreatment of vegetable waste.

► We studied the efficacy of assorted pretreatments on structural changes of lignocellulosic vegetable waste.
► Steam-sodium chloride pretreatment resulted in better structural changes of biomass.
► Enzymatic hydrolysis of various pretreated materials was carried out by in-house produced enzymes.
► Maximum hydrolysis of cellulosic material was attained with steam NaCl pretreatment.