Revalorization of agro-food industrial by-products based on sustainable phenolics extraction

ESPINO, MAGDALENA; SILVA, MARÍA F.; DE LOS ÁNGELES FERNÁNDEZ, MARÍA; GOMEZ, FEDERICO J. V.; BOITEUX, JOANA

Mendoza

Simposio; 24th Latin-American Symposium on Biotechnology, Biomedical, Biopharmaceutical, and Industrial Applications of Capillary Electrophoresis and Microchip Technology; 2018

Agro-food industry generates significant amounts of byproducts that are discarded and can be a serious environmental problem. Nevertheless, food by-products are an extraordinary source of bioactive compounds, including phenolic compounds1. The extraction, separation and determination of these compounds is performed by traditional schemes; such as solid phase extraction (SPE) with organic solvents or water, in combination with high resolution separation methods2. The development of new green agents for the substitution of hazardous solvents is one of the key subjects in Green Chemistry. In this sense, a new generation of solvents, called Natural deep eutectic solvents (NADES), has emerged in the last decade as promising green media. The common NADES components are sugars (glucose, sacarose, fructose, etc.); organic acids (lactic, malic, citric acids, etc.); urea and choline chloride3. In this work, an environmentally friendly method for the phenolic compound extraction from agro-food industrial byproducts was developed in order to contribute with their sustainable valorization. A NADES was chemometrically-designed and compared with traditional solvents in terms of analyte stabilization. The combination of lactic acid, glucose and 15% water (LGH-15) was selected as optimal. A high-efficiency ultrasound-assisted extraction mediated by LGH-15 prior to HPLC-DAD allows the determination of 14 phenols in onion, olive, tomato and pear industrial byproducts. NADES synthesis as well as the extraction procedures were optimized by Response Surface Methodology. Thus, phenolic determination in these complex samples was achieved by a simple, non expensive, eco-friendly and robust system. The application to different matrices demonstrated the versatility of the proposed method. NADES opens interesting perspectives for their potential use as vehicles of bioactive compounds as food additives or pharmaceuticals.