Chapter 9 - Levulinic acid: a potent green chemical in sustainable agriculture

Abstract

The accelerated demand, rising cost, chaotic geopolitical situation, and detrimental environmental impact of fossil fuels have necessitated the introduction of renewable alternative candidates and some sustainable solutions for the betterment of the future of mankind. Levulinic acid (LA) has been identified as one of the platform chemicals that could be produced from starch waste and lignocellulosic biomass via cost-effective chemical conversion which may play a key role in the protection of ecological, economical, and environmental sustainability. LA and its derivatives have many commercial applications in the preparation of pharmaceuticals, fuel and food additives, solvents, specialized biopolymers, agricultural products, and many more. At present, its production is solely based on the petrochemical route but research has shown efficient chemo-enzymatic conversion of cellulose and starch-based waste to LA is an environment viable option that could improve waste management procedures in sustainable agriculture systems. A large number of natural products (cellulose, fructose glucose, inulin), left over from cereals (kernel grain, sugarcane bagasse, corn stover, rice, and paddy straw), unused plant parts (sawdust of poplar, shoot shell of bamboo, pruning of olive tree), invasive weeds (water hyacinth) could emphasize the commercially applicable synthesis of this green chemical from renewable sources. However, the commercialization of the green synthesis of LA requires calibrated energy-efficient pretreatment, appropriate source selection, removal of agricultural waste transportation bottlenecks, an innovative technical collaboration of farmer-researchers-industry, and rigorous environmental and economical assessment. In this review, we have summarized the role of LA as a potential green chemical, enlisted its original, present, and probable sources, depicted the role of LA in different industrial sectors, emphasized the agronomical and technical advancements, highlighted the commercial bottlenecks and suggested some futuristic multifaceted research and development areas which may unfold a new chapter in agricultural waste management and green chemical synthesis without altering the key undertakings of sustainable agriculture.