Phytochemical Composition and Safety Evaluation of Aqueous and Methanolic Leaf Extracts of African grape (Lannea microcarpa) in Swiss Albino Mice

Abstract

African grape (Lannea microcarpa) is widely used in West African ethnoveterinary medicine for treating livestock diseases, including trypanosomiasis. However, comprehensive safety data on its leaf extracts are limited. This study evaluated the phytochemical composition and safety profile of aqueous and methanolic leaf extracts of L. microcarpa in mice. Fresh leaves were extracted using water and methanol. Phytochemical screening was performed using standard qualitative and quantitative methods. Acute toxicity was assessed following OECD Guideline 423 at doses of 1000, 3000, and 5000 mg/kg body weight. Sub-acute toxicity was evaluated over 21 days following OECD Guideline 407, including body weight gain, relative organ weights, serum biochemical parameters (hepatic and renal function), and histopathological examination of liver and kidney. Both extracts contained alkaloids, flavonoids, tannins, phenolic compounds, saponins, terpenoids, steroids, and cardiac glycosides. Methanolic extraction yielded significantly higher total phenolics (86.42 ± 6.31 mg GAE/g), terpenoids (72.54 ± 2.16 mg/g), and steroids (31.42 ± 1.27 mg/g), while aqueous extraction yielded higher flavonoids (98.34 ± 3.67 mg QE/g) and saponins (69.34 ± 2.18 mg/g). The oral LD₅₀ of both extracts exceeded 5000 mg/kg body weight. Sub-acute administration produced no significant changes (p>0.05) in body weight gain, relative organ weights, or serum biochemical parameters. Histopathological examination showed only mild, non-significant changes at higher doses. African grape (Lannea microcarpa) leaf extracts are rich in bioactive phytochemicals and possess a high safety margin, with LD₅₀ > 5000 mg/kg. Repeated oral administration for 21 days caused no significant hepatotoxicity or nephrotoxicity, supporting their safety for medicinal use.