Phytochemical Constituent and Toxicity Assessment of Methanol Leaf Extract and Fractions of Ficus exasperata Vahl in Rats

Abstract

Ficus exasperata Vahl is widely used in traditional medicine across Africa for the 
management of diabetes mellitus, hypertension, and other conditions. However, 
its safety profile remains inadequately characterized. This study evaluated the 
phytochemical composition as well as the acute and sub-acute oral toxicity of the 
crude methanol extract and fractions of F. exasperata leaves in Wistar rats. 
Phytochemicals, including total phenolics, flavonoids, alkaloids, saponins, and 
tannins, were quantified using standard spectrophotometric methods. Acute 
toxicity was assessed following a single oral administration of 2000 - 5000 mg/kg 
extract per animal according to OECD guidelines, while sub-acute toxicity was 
evaluated by daily oral administration of 300 mg/kg crude extract and fractions 
for 21 days. Biochemical indices of liver and kidney function (alanine 
aminotransferase, aspartate aminotransferase, urea, and creatinine) were 
measured. The extract and fractions contained appreciable levels of phenolics 
(0.55–2.51 mg gallic acid equivalents/g dry weight), flavonoids (33.98–57.03 mg 
quercetin equivalents/g dry weight), alkaloids (32.04%), saponins (8.10%), and 
tannins (4.04%). No mortality or overt signs of toxicity were observed at 5000 
mg/kg. However, repeated dosing for 21 days produced significant (p < 0.05) 
elevations in plasma transaminases, while urea and creatinine levels remained 
unchanged (p > 0.05). These findings suggest that F. exasperata leaf extracts 
are acutely safe but may exert hepatotoxic effects with prolonged use.