Natural occurrence of oleanolic acid and related pentacyclic triterpenoid saponins in traditional wound healing herbs

Oleanolic acid in a natural pentacyclic triterpenoid compound which occur widely in medical plants. Many traditional wound healing herbs contain saponin glycosides heaving oleanolic acid as aglycone. Oleanolic acid along with its structural isomer namely ursolic acid also has common occurrence in wound healing traditional herbs. Wound healing property of the traditional herbs in mainly due to their antibacterial, antiseptic, antiinflammatory and immunomodulatory properties. Antiinflammatory property of number of herbal drugs is mainly by inhibiting the cyclooxygenase (COX)-2 enzyme activity. Even it was found that saponins are effective against number of bacterial strains and fungi. Saponins are wonderful immunomodulators and rejuvenators by modulating the innate immune response. Rejuvenation always helps in reconstruction of granulating tissue and its maturation into a connective tissue which is a key process in wound healing. Well known saponin containing herbs like Leucas aspera, Olea europaea, Achyranthes aspera, Glycyrrhiza glabra, Ocimum sanctum, Panax ginseng etc., represents the significant effect on wound healing. Extracts of these herbs enhanced the proliferation, granulation tissue formation and collagen deposition in cutaneous wound healing. In conclusion, pentacyclic triterpenoid saponins have potential therapeutic role in process of wound healing. The present review is an approach to enlighten the natural occurrence of these saponins in traditional wound healing herbs.