South African Journal of Botany | 2019
Antioxidant, anti-inflammatory and wound healing properties of medicinal plant extracts used to treat wounds and dermatological disorders
Abstract Medicinal plants used for wound healing and skin diseases are key to unlocking the doors to combating resistance of pathogens to pharmaceuticals and allopathic management. This study was aimed at screening the antioxidant effects, the anti-inflammatory activity and wound healing capacity of traditional medicinal plants used in the treatment of skin conditions and wound healing in KwaZulu-Natal, South Africa. Eleven plant species were selected and separated into different plant parts (bulbs, roots and leaves) and extracted using 50% aqueous methanol. The extracts were assessed for their anti-inflammatory activity using the nitric oxide release and lipoxygenase inhibition assays. Almost all plant species exhibited some degree of anti-inflammatory activity. The observed antioxidant results (DPPH, FRAP, CLAMS) were significant for many of the extracts. The LOX revealed that five of the medicinal plant extracts, Bulbine natalensis, Eucomis autumnalis, Hypericum aethiopicum, Tetradenia riparia and Zantedeschia aethiopica were effective as anti-inflammatory agents with IC50 values below the quercetin control and ranged from 3.55\u202f±\u202f0.11 to 9.52\u202f±\u202f0.11\u202fμg/mL. The results of the wound healing assay/protein precipitating activity were significantly excellent for the three Aloe species, two Bulbine species and support scientific evidence from previous research. The protein-precipitating capacity as a wound healing model was significant for Haworthia limifolia 82.71\u202f±\u202f0.74% while the rest of the plant extracts had moderate to low values. In addition, medicinal plant extracts from E. autumnalis, H. limifolia, H. aethiopicum, T. riparia, and Z. aethiopica demonstrated promising and beneficial results for potential use in the treatment of skin diseases and wound healing. Antioxidant assays as well as anti-inflammatory assays (nitric oxide release and lipoxygenase inhibition assays) and wound healing assays support the dermatological and wound healing usage of these traditional medicinal plants and warrants further investigations and possible isolation of bioactive principles. Overall, the results from this multi-dimensional medicinal plant study provide extensive information on the 11 plant species and their various plant parts.