Microbial valorization of corncob: Novel route for biotechnological products for sustainable bioeconomy

Abstract Huge amount of renewable biomass in excess of 140 billion metric tons is generated annually due to agro-industrial activities. The agrowastes are often disposed indiscriminately or burnt off, thereby constituting environmental menace and contribute to global warming through the generation of greenhouse gases. Most frequently, the biomasses despite their richness in nutrients are also not found suitable for deserving applications. Among the agrowastes, generation of corncob occupies a prime position due to large scale cultivation of maize worldwide, as more than 200 million tons of corncobs are produced yearly. In recent times, to achieve environmental sustainability, value-addition to wastes, and promotion of advances in bio- and circular economy, agrowastes are now being investigated for valorization through biotechnological route. The preponderance of microbes with their concomitant production of different varieties of degradative enzymes makes them suitable for bioconversion of agrowastes to viable bioproducts in eco-friendly manner. The valorization of agrowastes is in direct responses to achieving five of the goals of SDG; particularly good health and wellbeing (SDG 3), clean water and sanitation (SDG 6), affordable and clean energy (SDG 7), industry and innovation (SDG 9), and climate action (SDG 13). In this review, we present recent activities on biotechnological valorization of corncob to create new range of bio- and nanoproducts to stimulate more research endeavours in this area.