Senna podocarpa Emulgel: A Herbal Alternative for Chemical Burn Wound Treatment

Abstract Senna podocarpa (SP) leaves are used in folk medicines for treatment of burns and wounds as poultices on wound surface. However, to the best of our knowledge, the wound healing ability of this plant has not been scientifically evaluated. This work aimed to determine the wound healing potential of the crude extract of SP leaves, and to evaluate the benefit of its preparation as an emulgel. In this study, the formulations of 2.5% of SP emulgel (F1) and 7.5% of SP emulgel (F2) were prepared by mixing the emulsion phase with the gel phase in a ratio of 1:1, and then physical appearance, globule size, pH, viscosity, swelling, water activity, extrudability, occlusion, spreadability, stability, and wound healing ability were determined. Phytochemical screening showed the presence of alkaloids, saponins, tannins, cardiac glycosides, flavonoids, anthraquinones, and phenols within the hydro-ethanolic extract of SP leaves, and high flavonoid content is believed to be responsible for its healing attributes. Our formulations showed acceptable physical properties. Hematoxylin-eosin and Verhoeff–Van Gieson stain showed that F2 could induce the accumulation of fibroblasts, fibrocytes, inflammatory cells, gland cells, epidermal cells, adipocytes, and collagen in the process of wound healing in mice injured with hydrochloric acid. Encouragingly, the percent of wound contractions in mice treated with F1, F2, and SP leaf poultice were 64, 87, and 50, respectively, suggesting the superior healing properties exhibited by SP emulgel over SP leaf poultice, and this may due to the occlusive property of emulgels. In conclusion, F2 of crude extract of SP leaves has better pharmacological effects on burn and wound healing, and may represent a preferred choice to treat burn wounds in the future.