Utilization of Eggshell Membrane and Olive Leaf Extract for the Preparation of Functional Materials

Foods. 2021 Apr 9;10(4):806. doi: 10.3390/foods10040806.

Abstract

Eggshell membrane (ESM) is a natural proteinaceous by-product of the food industry, especially in the pasteurized egg industry, resulting in the availability of much discarded egg waste. In the literature, eggshell (ES) and ESM usage for their adsorbent properties to remove various organic and inorganic hazardous chemicals, especially from wastewater, has gained interest. In addition, agricultural (olive leaf) and food industry (eggshell and eggshell membrane) waste can together be valorized to produce value-added functional products. This study's objective was to evaluate the eggshell membrane's loading capacity for bioactive compounds obtained from olive leaf extract (OLE) in order to prepare functional biomaterial. In this study, waste eggshell membranes were used to adsorb the phenolic compounds from olive leaf extract to design functional biomaterials. Using the foam separation method, both separation of the eggshell membrane and adsorption of bioactive compounds to the eggshell membrane were achieved simultaneously. The characterization studies showed that OLE was successfully adsorbed to the eggshell membrane. Cytotoxicity and antimicrobial studies showed that prepared OLE-loaded membranes were functional materials with bioactive properties. In conclusion, ESM was determined as a promising protein in the production of functional antioxidative and antimicrobial food or dietary supplement after the adsorption of bioactive olive leaf polyphenols.

Keywords: antimicrobial; cytotoxicity; eggshell membrane; functional material; olive leaf extract.