EVALUATION OF WOUND HEALING AND ANTIBACTERIAL ACTIVITIES OF 80% METHANOL CRUDE EXTRACT OF THE LEAVES OF EHRETIA CYMOSA THONN (BORAGINACEAE) IN MICE MODEL

Abstract

Ehretia cymosa is one of the medicinal plants used traditionally for the treatment of wounds and a range of ailments including fever, gastric ulcer, dysentery, and toothache. However, the scientific evidence justifying its pharmacological effect from a preclinical perspective is scant. Objective: The present study was conducted to evaluate wound healing and antibacterial activities of 80 % methanol extract of Ehretia cymosa leaves in mice. Materials and Method: Air dried and powdered leaves of Ehretia cymosa were extracted by cold maceration using 80 % methanol. The extract was studied for determination of its anti- bacterial activity using disk diffusion technique against common bacteria associated with wound infection at a concentration of 100-300 mg/ml. The extract was tested for acute dermal toxicity using a limit test dose of 2000 mg/kg of the 10 % formulation. To evaluate wound healing activities; three wound models excision, incision and burn followed by infection were employed. The extract was also evaluated for the presence of secondary metabolites using standard tests. A one way Analysis of Variance followed by Tukey‘s post hoc multiple comparison tests was used to compare the means of all parameters among groups and within groups. Results: Ehretia cymosa leaves showed significant (p< 0.01) antibacterial activity against the tested bacteria in a dose-dependent manner, a minimum inhibitory concentration ranged from 6.25-75 mg/ml against the tested bacteria and minimum bactericidal concentration against Pseudomonas aeruginosa and Escherichia coli at the concentration of 200 mg/ml were observed. The extract showed no acute dermal toxicity as it was evidenced by zero primary irritation index. Topical ointments using two concentrations of 5% and 10% w/w, resulted in concentration- dependent significant (p< 0.05) wound healing activity in all wound models compared to the negative control. The plant was found to be rich in flavonoids, terpenoids, and tannins. Conclusions: 80 % methanol extract of the leaves of Ehretia cymosa showed wound healing activities this might be due to its sever collagen deposition, antibacterial effect, and presence of secondary metabolites. It is recommended to fractionate for future pharmacological researches, to purify, and identify the active compound with wound healing activities and antibacterial effects