Valorization of orange peels as a source of natural antioxidants from pectin-extracted compounds

Citrus peels, a major by-product of the fruit industry, are rich in pectic polysaccharides with potential bioactive properties. This study aimed to extract and characterize pectin from orange peels and to evaluate its physicochemical properties and antioxidant potential. The extracted pectin was analyzed for its physicochemical characteristics, and its antioxidant potential was assessed using three in vitro assays: DPPH, ABTS, and FRAP. The extraction yielded 19.0% dry material, with moisture (13.0%), ash (10.3%), total sugars (16.3%), and protein content (0.10%). Phytochemical analysis showed low levels of polyphenols (1.17 mg GAE/g DM), flavonoids (0.55 mg QE/g DM), and condensed tannins (0.10 mg CE/g DM). Despite these low phenolic contents, the pectic extract exhibited significant antioxidant activity in DPPH, ABTS, and FRAP assays, with IC₅₀ values of 2.32, 2.00, and 1.85 mg/mL, respectively. These findings indicate that orange peel pectin is a promising natural antioxidant source with potential applications in the food, nutraceutical, and pharmaceutical industries, promoting the sustainable valorization of citrus by-products.