Valorization of olive mill wastewater using adsorption resins for pharmaceutical and cosmetic applications

The valorization of food wastes is a challenging opportunity for a green, sustainable and competitive development of industry. In Mediterranean area approximately 30 million m3 of olive mill wastewater (OMW), characterized by a high pollutant load, are produced annually as byproduct of the extraction process of olive oil. OMW presents high values of chemical oxygen demand (COD), suspended solids and several pollutants difficult to biodegrade (such as tannins, polyphenols and lipids) which may exert phytotoxic effects. However, in addition to being a serious environmental and economical issue, OMW can also represent a precious resource of potentially valuable molecules such as polyphenols (or "biophenols"), and carbohydrates. In particular, biophenols like hydroxytyrosol, tyrosol, oleuropein and verbascoside show an acclaimed antioxidant activity and can find useful applications in pharmaceutical and cosmetic industry. In this work OMW were treated with different adsorption resins to obtain chemically distinct pools of molecules characterized by high contents in poliphenols or carbohydrates. The fractions were tested both for moisturizing suitability in cosmetic, and in eye drops formulation for ophthalmic applications (ophthalmic nutraceuticals). Optimization and recycle of the adsorbent materials were studied as well. To evaluate the feasibility and the economic value at industrial level, the procedure is actually undergoing a scale-up process and the development of an automatized pilot prototype is in progress.