Wound healing, antimicrobial and antioxidant properties of the leaf and stem bark of Entada africana Guill. & Perr.

Abstract Entada africana (Mimosaceae) is widely used in African traditional medicine as a wound healing agent. This study investigated the wound healing, antimicrobial and anti-oxidant activities of the leaf and stem bark of E. africana in order to scientifically validate its wound healing properties. Methanol extracts of the leaf and stem bark were formulated into creams (5–20%) and tested in the dermal excision wound model in rats. The broth dilution assay was used to determine the antimicrobial activity; DPPH free radical scavenging, ferric reducing power, total antioxidant capacity, total phenolic and total flavonoid content were determined to assess the antioxidant activity. Significant wound healing was demonstrated by topical application of the extract creams. By the 10th day, a total wound surface closure of 98.8%, 95.8%, 96.3% and 73.9% was observed for the 10% stem bark and leaf creams, standard drug and blank cream treated groups respectively. Histopathological examination of the healed tissue sections showed significant collagen production, scanty inflammatory cell infiltrates and re-epithelialization whereas tissues from the blank cream treated group displayed focal areas of abscess and diffused inflammatory cells. The methanol stem bark extract demonstrated antibacterial activity against S. aureus and S. pyogenes with a minimum inhibitory concentration of 1.56 mg/mL. The stem bark and leaf had antioxidant activity and were found to contain a total phenolic content of 47.25 and 133.7 mg/g Gallic acid equivalent respectively and total flavonoid content of 21.06 and 88.21 mg/g quercetin equivalent respectively. The above results indicate that the leaves and stem bark of E. africana have great potential for the treatment of open wounds.