Phytochemical profile, acute oral toxicity, antioxidant, and antispasmodic effects of ethyl acetate and aqueous residual fractions of Diospyros mespiliformis Hochst. ex A. DC (Ebenaceae) leaves on isolated duodenum of rat

Abstract

Introduction: Diospyros mespiliformis Hochst. ex A. Rich (Ebenaceae) is a nutritional, artisanal and medicinal plant. It is used in alternative medicine in Burkina Faso for the treatment of conjunctivitis, menorrhagia, dysentery, and especially diarrhea. Aims: Our study aimed to evaluate the chemical profile, the antioxidant and anti-inflammatory activities, the safety of use, and the spasmolytic effects of the fractions obtained from the aqueous decoction of the leaves of Diospyros mespiliformis. Methods: Phytochemical screening by HPTLC and the determination of compounds of interest were carried out. The antioxidant activity was evaluated according to the ABTS, DPPH, FRAP, and LPO methods. The inhibitory activity of Phospholipase A2 and 15-lipoxygenase was evaluated. Acute oral toxicity was carried out on female mice (NMRI). The ex vivo spasmolytic effect of the fractions was tested on isolated rat duodenum using ACh and BaCl2 as contracting agents. Results: At the end of these tests, the fractions contain flavonoids, tannins, sterols, triterpenes, and saponosides. The content of total phenolics was respectively for the ethyl acetate fraction (EAF) and the residual aqueous fraction (RAF) 84.15±1.73 mg EAT/g and 89.67±2.35 mg EAT/g. That of flavonoids was respectively 45.91 ± 0.98 mg EQ/g and 10.46±0.28 mg EQ/g for the two fractions. The 50% inhibitory concentrations (IC50) of EAF for the ABTS, DPPH, and FRAP tests were 2.26±0.16 μg/mL, 22.34±7.23 μg/mL and 1136.25±0.90 mol EAA/g respectively, and an inhibition % of 43.80 ± 6.31% for LPO. For RAF, the IC50 were in the same range as EAF of 16.82±0.23 μg/mL, 18.58±2.91 μg/mL, 1138.4±1.27 mol EAA/g and an inhibition of 45.14±10.35% for LPO. The fractions had an inhibitory effect on phospholipase A2 compared to Betamethasone. Finally, the most active EAF caused a spasmolytic effect with Emax of 87.4±15.71% and 90.40±7.84%, respectively, during contractions induced by BaCl2 and ACh. Conclusion: Finally, this work provided scientific data and could justify the use of D. mespiliformis leaves in the treatment of diarrhea.
 Keywords: Diospyros mespiliformis, Leaves, Antioxidants, Anti-inflammatory, Safety of use, Spasmolytic