Exploration of Serbian biodiversity for the discovery of bioactive natural products with skin beneficial effects

Abstract

The Balkan Peninsula has a long tradition in folk medicine and a plethora of plant species are utilised in treating skin disorders [1]. Within the context of the EU project “EthnoHERBS”, the aim of this study was the phytochemical and biological investigation of Serbian plants that have been traditionally used in the treatment of skin ailments (hyperpigmentation, wound healing). Eighty two plant species, selected based on ethnobotanical studies, were extracted successively with dichloromethane, methanol and methanol:water (1:1) and their chemical profile was investigated through high-performance thin-layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC DAD). The total phenolic (TPC) and total flavonoid content (TFC) were evaluat ed using the Folin-Ciocalteau and the aluminium chloride colorimetric method, respectively. The antioxidant capacity of extracts was determined through the DPPH assay (concentration of 200 µg/mL), and their anti-tyrosinase and an ti-collagenase activity was tested at a concentration of 300 µg/mL and 100 µg/ mL, respectively. Several secondary metabolites were detected in the extracts such as terpenes, flavonoids, tannins, etc. The highest antioxidant activity was found in the extracts of Mentha longifolia, Hypericum perforatum and Cotinus coggyria. The hydroalcoholic and the methanolic extracts of Cotinus coggyria demonstrated the best anti-tyrosinase (IC50 = 36.27 μg/mL) and the best an ti-collagenase (IC50 = 18.13 μg/mL) activity, respectively. In conclusion, ex ploitation of traditional knowledge can provide valuable information for the development of natural products with beneficial skin effects