Asian Journal of Research in Biochemistry

Leaves of plants, especially soursop (Annona muricata), have been widely exploited for feed formulation, functional food, and medicinal purposes owing to their rich supply of phytochemicals and natural antioxidants. This study was aimed at investigating the phytochemical constituents and the antioxidant activity of soursop leaf extracts using Ferric Reducing Antioxidant Power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, and hydroxyl radical scavenging assays. In soursop leaves, a total of twelve phytochemicals were detected. The results revealed high amounts of anthocyanin (5.34±0.007%), phenol (3.80±0.077 mg/g), alkaloids (3.31±0.077%), cyanogenic glycosides (2.65±0.022%), cardiac glycosides (2.27±0.041%), saponin (1.78±0.021%), flavonoids (1.14±0.099%), tannins (1.06±0.020%), and steroid (1.03±011 mg/g), but low amounts of phytate (0.65±0.024%), oxalate (0.33±0.011%), and hemagglutinin (0.08±0.012 mg/g). Antioxidant assays proved concentration-dependent properties of the aqueous extract of soursop leaf. Strong Fe³⁺ ion reduction was demonstrated by the maximum FRAP activity (63.76±0.014%), which was recorded at 80 mg/ml. Also, the leaf extract was most effective at scavenging DPPH free radicals (87.541%) and hydroxyl radicals (64.045%) at 10 mg/ml and 20 mg/ml, respectively. High anthocyanin, phenolic, and flavonoid contents found in this study suggest that soursop leaf holds weighty antioxidant potential, with implications for protecting against oxidative stress-related damage and potential as a beneficial functional food.