Valorization of agro-industrial residues for production of commercial biorefinery products

Agro-food industrial residues (AFIRs) are produced in vast amounts around the world. These wastes are commonly called lignocellulosic wastes that are a source of value-added products. Solid-state fermentation (SSF) for bioconversion of lignocellulosic waste, which produces various bioproducts, has economic and environmental advantages. The lignocellulosic compounds are biorenewable and most plentiful resource on earth that can be utilized for manufacturing value-added products. Furthermore, the use of lignocellulosic, starchy, and other agro-industrial by-products in the manufacture of these biomolecules has yet to be thoroughly investigated. As a result, there is a vast opportunity for the development of cost-effective, sustainable biorefining technologies. The main components of lignocellulosic biomass used in biorefineries are cellulose, hemicellulose and lignin. To obtain final biobased products, these components must be processed through a series of procedures that include pretreatments, enzymatic hydrolysis, and fermentation. Biotechnology techniques and process engineering are critical in developing integrated processes for producing various value-added products from lignocellulosic biomass, including biofuels, biochemicals, bioactive substances, enzymes, and biomaterials. This review focuses on the valorization potential of lignocellulosic, palm oil mill, brewing, and dairy biomass produced as agri-food industrial by-products for developing biobased products in the biorefinery scenario. It is the first review of its kind to include variety of products that can be derived from different wastes encircling all the pros and cons of current technology and focusing on future improvements.