Biological pretreatment for algal biomass feedstock for biofuel production

Addressing the ever-increasing global demand and limiting the dependency on exhaustible fossil fuels led to the foundation for renewable energy research. Biomass obtained from algae seems as a promising feedstock for biofuel production. For the optimal recovery of biofuel, pretreatment of algal biomass is a primary element. This review discusses different biological routes of pretreatment used for algal feedstock, including whole-cell, fungal, and bacterial pretreatments. This manuscript also extensively covers enzymatic pretreatment and its approaches toward augmenting enzyme performances and enhancing biofuel production. Additionally, mutagenesis approaches by rational, semi-rational, and de novo designs using bioinformatics and biotechnological tools are also discussed. Furthermore, how chemical modification of enzymes using non-canonical amino acids and organometallo cofactors improve biofuel production is highlighted. Bioprospecting for biofuel production is an important area of research that contributes to sustainable and renewable energy development using screening of natural habitats, genetic modifications, synthetic biology, and metagenomics approaches. This study gives insight into different biomass pre-treatment and biofuel production methods, especially biogas, biohydrogen, and bioethanol. Furthermore, the review explores the comparative assessment of biological pretreatment of algal biomass and shows that biological processes can result in better biofuel yield from algal biomass.