Preliminary Phytochemical Screening and Antioxidant Activity of Robusta Coffee Blossom

Abstract

The Robusta coffee flowers were analyzed for phytochemical composition and antioxidant activity. Flower powders at three different stages were extracted successively with hexane, dichloromethane and methanol, resulting in the extracts of varying yields (1.61-16.01%). All crude extracts were constituted of flavonoids, terpenoids and alkaloids. The methanol crude extracts exhibited the best antioxidant activity on both DPPH (EC₅₀ 0.03-0.13 mg/mL) and reducing power (EC₅₀ 0.19-0.46 mg/mL). It also contained the highest amount of total phenols (28.32-139.88 mg GAE/g extract).