ABSTRACT
The issue of sustainable biofuels for the transportation sector is gaining attention due to strict international and national regulations, specifically with respect to eco-friendliness and the potential for reduction of greenhouse gases with biofuel usage. Cellulose from lignocellulosic biomass can be used to produce bioethanol, however doing so requires additional processes using enzymes to break down the cellulosic materials into sugars. Liquid wastes like kitchen food waste and commercial food waste, sludges from sewage, animal dung, and agricultural waste can be utilized incorporating different enzymes such as cellulases, amylases, pectinases, lipases, and proteases for the valorization of these liquid wastes in bioethanol and petrochemical production. The hydrolytic enzymatic conversion of agricultural waste to bioethanol can be performed utilizing Hymenobacter sp. CKS3. Hymenobacter genus has been relatively less explored and offers huge potential for bio-based industrial applications. Cellulosic ethanol also has the hypothetical ability to provide substantial lifecycle GHG reductions compared to petroleum-based gasoline. Hence an “enzymatic-valorization” strategy needs to be in place to convert lignocellulosic biomass (LB) using second-generation biofuel production into multifarious bio-based valuable products. This chapter discusses strategies for enzymatic bioethanol production and biofuels valorization considering the different types of wastes utilized and the enzymes used for the conversion process.
