Aim of the study: In South Africa the local population relies extensively on indigenous plants in the formulation of traditional medicines to treat skin ailments. The scientific merits of many of these plants used to treat wounds and burns are yet to be validated. Bulbine (B.) natalensis and B. frutescens of the Asphodelaceae family are indigenous to only southern Africa and are widely used as a skin remedy. This study aimed to explore the scientific value of these plants through investigating the in vivo biochemical effects of B. natalensis and B. frutescens on cutaneous wounds.
Material and Methods: Excisional and incisional wounds treated with either B. natalensis or B. frutescens and mirrored control wounds were created on the back of 12 domestic pigs. Wound contraction was recorded daily. The excisional wounds, biopsied at days 2, 4, 7, 10 and 16, were used to analyse the biochemical composition of the wounds by estimating the total amount of protein, DNA, collagen and hexosamine present. The incisional wounds, biopsied at day 16, were used to test the tensile strength of the healed wounds using a tensiometer.
Results: Wound contraction following treatment with B. natalensis on days 2, 4 and 10 (p = .004, 0.007 and 0.03, respectively), and B. frutescens on day 4 (p = 0.004) increased significantly when compared to the corresponding untreated wounds. The tensile strength of the wounds treated with the leaf gels was significantly stronger than that of the untreated wounds. There was also a significant increase in the collagen, protein and DNA content of the B. natalensis- and B. frutescens-treated wounds compared with that of the untreated wounds (collagen content: p = 0.014 and 0.018; protein content: p = 0.03 and 0.04; DNA content p = 0.04 and 0.04; respectively) over the 16-day experimental period. Treatment with both leaf gels followed the same pattern in hexosamine content with a maximum hexosamine content on day 4 followed by a steady decrease to day 16. No significant difference between the hexosamine content of the wounds of animals treated with either B. frutescens or B. natalensis was found.
Conclusions: These findings validate the traditional use of the leaf gel extracts of B. frutescens and B. natalensis in the treatment of wounds and may warrant further investigation towards producing a low-cost effective topical treatment for wounds.