Study on wound healing activity of Punica granatum peel

The methanolic extract of dried pomegranate (Punica granatum) peels showed the presence of a high content of phenolic compounds (44.0%) along with other constituents. This extract was formulated as a 10% (wt/wt) water-soluble gel and was studied for its wound healing property against an excision wound on the skin of Wistar rats. The activity was compared with that of a commercial topical antibacterial applicant. The wound healing activity was assessed by measuring the percent contraction in skin and estimation of collagen content in terms of hydroxyproline content. Healed skin was also subjected to histopathological studies to examine the microscopic changes. The animals treated with 2.5% gel showed moderate healing (55.8% and 40.8% healing compared with negative and positive controls, respectively), whereas the group treated with 5.0% gel showed good healing (59.5% and 44.5% healing compared with negative and positive controls, respectively). The amount of hydroxyproline increased by twofold in the group treated with 5.0% gel. Histopathological studies also supported the wound healing on application of the gels. The group of rats that received 5.0% gel showed complete healing after 10 days, whereas in rats treated with 2.5% gel, healing was observed on day 12, in contrast to the positive control animals receiving the blank gel, which took 16-18 days for complete healing. The results of this study may be extended to different types of wounds so that the formulation could be exploited to develop it as a topical dermatological formulation. High-performance liquid chromatography analysis of the extract showed the presence of gallic acid and catechin as major components.