Antioxidative Potentials of Annona muricata Pulp and Allium cepa Bulb Juices

Aim: To establish the in vitro antioxidative potentials of juice samples of Annona muricata (soursop) fruit pulp and Allium cepa (onion) bulb. Study Design: The experimental research design was adopted in this study, but without intervention. Place and Duration of Study: Springboard Laboratories, Awka, Nigeria, in June 2022. Methodology: Traditional method of juice preparation was used to prepare the juices of the soursop fruit pulp and onion bulb. The parameters assayed for were; ferric reducing antioxidant power (FRAP), nitric oxide, ABTS (2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid), superoxide, hydrogen peroxide (H2O2), DPPH (2,2-diphenyl-1-picrylhydrazyl), hydroxyl radical scavenging activities, total phenol content, total antioxidant capacity, and total flavonoids content using standard laboratory techniques at 100, 200 and 300 mg/ml concentrations of the samples in triplicates. Appropriate standards were set up alongside the tests to compare antioxidant properties of the test sample. Results: The results showed that Annona muricata pulp and Allium cepa bulb juices, at the concentrations studied, possessed these antioxidant properties studied in varying quantities. It was also observed that values for total antioxidant capacity for soursop juice at 300 mg/ml concentration, and ABTS scavenging activity for onion juice at all concentrations were significantly higher than the reference. The value obtained for DPPH scavenging activity for onion juice at 300 mg/ml concentration and total flavonoids content for onion juice were statistically similar to the reference. Conclusion: Both juices are natural sources of exogenous antioxidants which can be exploited to benefit humans.