Abstract
Philostigma thonningii (Schum.) is used in many parts of West Africa including Kebbi State, Nigeria for the management of wounds, chronic ulcers, gastric heart pain, and headache. It has been estimated that nearly 6 million people suffer from chronic wounds worldwide. This study aimed to investigate the wound healing activity of Philostigma thonningii leaves. The air-dried powdered leaves were extracted by maceration in methanol to obtain a crude methanolic extract (CME). The CME was screened phytochemically, then prepared into 2.5, 5 and 10% CME ointment by fusion before subjecting to wound healing assay using the wound excision model in Wister albino rats. The results showed a non-dependent dose healing effect owing to CME ointment since wound contraction at 2% and 5% CME treatment yielded higher percent contraction compared to that of 10% maximum dose administered. Comparatively, the treatment groups with CME showed better wound closure and re-epithelization of tissue repair and fibroblast in the granulation tissue formation than those in the untreated group of the negative control (in Group I, DW). However, the animals treated with 5% povidone iodine, PI (in Group II, Standard), showed a better wound contraction and arrangement of granulated tissue repair than those of both the CME treated group and the DW groups in the experiment. Consequently, there was no significant difference (p > 0.05) observed between wounds treated with CME (2.5, 5 and 10) % of P. thonningii leaves, except the standard treatment group with 5% PI, which showed significantly (p<0.05) wound healing activity. Conclusively, the observed wound healing activity of P. thonningii leaves may be attributed to a single or a synergistic effect of phytochemical constituents. The findings have also justified the traditional medicinal uses of P. thonningii leaves for the management of wounds.

Key words: Contraction, Excision, Povidone-iodine, Re-epithelization, Wound healing