Comparative Impact of Solvent Extracts of Spondias mombin Leaves on In-vitro Antioxidant and Acetylcholinesterase Inhibitory Activities
Uduenevwo Francis Evuen *
Department of Biochemistry, College of Natural and Applied Sciences, Western Delta University, P.M.B. 10, Oghara, Delta State, Nigeria.
Enyohwo Dennis Kpomah
Department of Biochemistry, Federal University, Otuoke, Bayelsa State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
The underlying cause of a number of neurological disorders is oxidative stress. Given the dearth of medications now available to treat such disorders and their accompanying detrimental impacts, an urgent need exists for the global identification of brand-new antioxidants and acetylcholinesterase (AChE) inhibitors. This study evaluated the comparative impacts of the antioxidant and acetylcholinesterase activities of n-hexane, ethyl acetate, and methanol extracts of S. mombin leaves. The dried leaf samples of the plant were triturated. Following maceration of the powdered plant materials in each of the three extraction solvents (methanol, n-hexane, and ethyl acetate), the resulting solutions were separately subjected to lyophilization. The in-vitro antioxidant analysis was determined by employing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and lipid peroxidation (LPO) assays. Acetylcholinesterase (AChE) inhibitory abilities of the various extracts were also evaluated using a standard protocol. The methanol extract showed the greatest DPPH scavenging (75.91%) and AChE inhibitory (40.17%) properties in the DPPH and AChE inhibitory assays, respectively. The DPPH and lipid peroxidation assays also demonstrated that all extracts had dose-dependent antioxidant properties. In addition, evaluations of each extract's ability to inhibit lipid peroxidation revealed that, at initial concentrations of 0.05 mg/L and 0.1 mg/L, the methanol extract displayed stronger LPO inhibitory effects (5.90%, 6.15%) than the n-hexane (4.00%, 5.4%) and ethyl acetate (3.26%, 3.99%) extracts. Nonetheless, the n-hexane extract showed a greater LPO inhibitory effect (10.00%, 10.34%) at higher dosages of 0.2 mg/L and 0.5 mg/L respectively. The results of this study have shown that methanol is the best solvent for exploiting the pharmacological benefits of S. mombin leaves thereby reasserting the numerous applications of the plant in traditional medicine. It has also paved the way for the development of novel therapeutic alternatives for a range of neurodegenerative disorders and other health concerns.
Keywords: Acetylcholinesterase inhibitor, natural antioxidant, lipid peroxidation, solvent extracts, neurodegenerative disorders