Polyphenol Profile and Antioxidant Potential of Peels from Anna andGolden Dorsett Apple Varieties Grown in Uganda

Abstract

Introduction: This study characterized the polyphenol profile and antioxidant properties of peels from two Ugandan-grown apple varieties (Anna and Golden Dorsett) and compared them to an imported variety (Cripps Red) Methods: The polyphenol composition and antioxidant properties in apple peels were analyzed using High Performance Liquid Chromatography (HPLC). Results: A total of 19 polyphenols were identified in Anna and 18 in Golden Dorsett and Cripps Red. Ugandan-grown apple varieties had higher total polyphenol content (474.88–489.96 mg/100g) than Cripps Red (453.39 mg/100g). Ellagic acid (111.32–113.93 mg/100g) and cinnamic acid (58.07–101.89 mg/100g) were significantly (p <0.05) more abundant in Ugandan-grown apples than in Cripps Red. Antioxidant activity was highest in Anna (85.13%), followed by Golden Dorsett (79.51%) and Cripps Red (71.04%). Total antioxidant capacity was highest in Golden Dorsett (148.72 mM-TE), followed by Crips Red (147.95 mM-TE) and Anna (113.37 mM-TE). Discussion: Since the apple varieties grown in Uganda were harvested from the same orchard, variations in their polyphenol profiles could be due to varietal difference while the observed difference between Cripps Red and the Ugandan-grown apple varieties could be due to both variety and geographic location. The higher polyphenol levels observed in the peels of apple varieties grown in Uganda relative to Cripps Red and other global varieties may stem from genetic variability coupled with local climatic and soil factors. Conclusion: The study findings revealed that peels from locally grown apple varieties in Uganda have higher polyphenol content and stronger antioxidant properties compared to the Cripps Red variety.