Secondary chemical building blocks from novel biorefining of agrifood wastes for a future bio-based industrial chemistry

Currently phenols are produced by the chemical industry from fossil hydrocarbons such as coal (which contains 0.2% of phenols) or petroleum. Biomass (which contain 5-8% of phenols) represents a substantial source of under-exploited phenols. By recovering phenols from biomass in the form of secondary chemical building blocks, PHENBUSTER (on the basis of economic and industrial considerations) develops an approach that represents a generally valid solution, due to the fact that these building blocks feed numerous chemical processes. Agro-food wastes contain different type of phenols which are characteristics of the different vegetables used for the food production. On the basis these wastes can then constitute important industrial source of biophenols. The industrial recovery of the biophenols is however limited by some prominent problems to be solved: 1) the distant location and the recovery of wastes on the territory; 2) the low concentration of bio-phenols in comparison to the large amount of wastes to be treated; 3) the management of a large amount of wastes to be transported to the extraction plant and the relative costs; 4) the large amount of wastes to be treated in time due to the scarce stability of the wastes and their seasonality; 5) the high-costs for the special disposal of the exhausted waste after solvent extraction. Furthermore, the biophenols are mainly water soluble, water soluble-esterified and insoluble-bound covalently linked to the polysaccharidic backbones of the vegetable cell wall. In this communication we demonstrate the possibility to perform an extraction of the phenolic fraction from different agro-food wastes throughout a patented adsorption/desorption process using the weak ion exchange after an enzymatic pre-treatment which was developed in order to hydrolyse the vegetable cell wall structures and to release the covalently linked phenolics. The bio-catalytic treatment was used instead of the typical acidic/basic hydrolysis because of the possibility of a easier scale up of the process Our findings demonstrate an economical feasibility for the recovery of biophenols from agrifood wastes through a whole crop approach in a sustainable biorefining process