Phytochemical, Antioxidant, Anti-Nociceptive and Anti-Inflammatory Studies of the Water and Methanol Extracts Obtained from the Leaves of Fagaropsis Angolensis (Engl.) H.M. Gardner (Rutaceae)

Abstract

Fagaropsis angolensis is widely used in African traditional medicine system to manage oxidative stress-associated diseases and lacks scientific evidence. The study investigated the phytochemical, antioxidant, anti-nociceptive and anti-inflammatory properties of F. angolensis leaf extracts. Extracts were prepared by maceration and standard qualitative methods were used for phytochemical screening. Total phenolic and total flavonoid contents were done by using Folin-Ciocalteu and aluminum chloride calorimetricmethods, respectively. Antioxidant activity was evaluated using 2, 2-Diphenyl-1- picrylhydrazyl (DPPH) method. Acetic acid-induced writhing and carrageenan-induced hind paw edema mouse models were used in anti-nociceptive and anti- inflammatory activities respectively. The presence of steroids, phenols, alkaloids, flavonoids, anthraquinones, glycoside and coumarins were observed. Total phenolic content for methanol extract was 55.52 ± 3.05 and the water extract was 48 ± 0.185 mgGAE/g (p<0.05). While, total flavonoid content for methanol extract was 172.53 ± 7.095 and that of water extracts was 42.23 ± 0.101 mgCE/g (p<0.05). IC50 values of less than 1 μg/ml were revealed in the DPPH assay. Percentage (%) writhing inhibition did not show any difference between the tested doses of plant extracts and standard aspirin at 150 mg/kg (p>0.05), indicative of potent anti-nociceptive activity. There was no significant difference in percentage paw edema inhibition between the plant extracts and the dexamethasone standard at 10 mg/kg (p>0.05), indicative of potent anti-inflammatory activity.This study adds to existing knowledge about the utilization of F. angolensis in traditional medicine for the management of related to oxidative stress including pain and inflammatory reactions.