Fingerprinting Agro-Industrial Waste: Using Polysaccharides from Cell Walls to Biomaterials

Climate change resulting from human development necessitates increased land use, food, and energy consumption, underscoring the need for sustainable development. Incorporating various feedstock into value-added liquid fuels and bioproducts is essential for achieving sustainability. Most biomass consists of cell walls, which serve as a primary carbon source for bioenergy and biorefinery processes. This structure contains a cellulose core where lignin and hemicelluloses are crosslinked and embedded in a pectin matrix, forming diverse polysaccharide architectures across different species and tissues. Nineteen agro-industrial wastes were analyzed for their potential use in a circular economy. The analysis included cell wall composition, saccharification, and calorific potential. Thermal capacity and degradation were similar among the evaluated wastes. The feedstocks of corn cob, corn straw, soybean husk, and industrial paper residue exhibited a higher saccharification capacity despite having lower lignin and uronic acid contents, with cell walls comprising 30% glucose and 60% xylose. Therefore, corn, soybean, industrial paper residue, and sugarcane are more promising for bioethanol production. Additionally, duckweed, barley, sorghum, wheat, rice, bean, and coffee residues could serve as feedstocks for other by-products in green chemistry, generating valuable products. Our findings show that agro-industrial residues display a variety of polymers that are functional for various applications in different industry sectors.