Antioxidant activities of ethanolic extract of Annona muricata against different pro-oxidant induced lipid peroxidation in rat brain and liver

Background and objective: Over the years, numerous works have documented the antioxidant potency of Annona muricata as well as it medicinal actions against myriad of ailments. However, there is still vague information as regard its antioxidant ability against diverse types of prooxidants. This work is carried out to deduce the antioxidant capacity of ethanol extract of A. muricata against different pro-oxidants in the cerebral and hepatic tissues of rats in in vitro models. Methods: Fresh leaves of A. muricata were washed, air-dried, pulverized and extracted with ethanol. Rats were euthanized and the tissues (brain and liver) were removed and homogenized in 50mM Tris-HCl, pH 7.4. The homogenates were centrifuged for 10min at 4000rpm to obtain a low-speed supernatant that was used for TBARS assay in the presence of extract and five different pro-oxidants; Iron (II) sulphate, hydrogen peroxide, 3-Nitropropionic acid, Sodium nitroprusside and quinolinic acid. Results: The results reveal that A. muricata extract displayed strong potency against lipid peroxidation in both the brain and liver tissue homogenates by inhibiting the production of thiobarbituric acid reactive substances irrespective of the prooxidant used. This polytropic antioxidant ability of A. muricata extract could be linked to its high polyphenolic content which confers on it, a strong redox property as well as a hydrogen donating power. This research therefore paves way for further investigation on the therapeutic actions of A. muricata in lipid peroxidation mediated ailments and diseases.