Emerging chemo-biocatalytic routes for valorization of major greenhouse gases (GHG) into industrial products: A comprehensive review

Climate change is one of the major global concerns of 21st century, and the release of excessive greenhouse gases (GHG) is the foremost reason behind. It has become imperative to either capture excessive emission of GHG into the atmosphere or to develop advanced and efficient technologies for preventing further increase in its atmospheric concentration. Algal and microbial enzymes have been found to be effective in catalyzing the conversion of GHG to value-added products like biofuels, chemicals, polymers, biogas, and bioelectricity etc. However, these enzymes yield better catalytic activities when applied in combination with nano-materials having similar prowess for capturing and converting GHG. Replacing conventional chemical production through GHG capture and utilization affects emission of the same throughout the production chain (i.e., from cradle-to-gate). Herein, we analyze the technical potential of hybrid chemo-biocatalytic processes for GHG capture and their utilization to produce valuable industrial compounds. The study addresses the biosynthesis as well as genetic and metabolic engineering of different microbial enzymes for GHG sequestration and conversion. It also reviews recent literature of using different advanced materials for immobilization of enzymes and their subsequent application for GHG sequestration and conversion to valuable products.