Pigments, Polyphenols and Antioxidant Activity of Leaf Extracts from Four Wild Rose Species Grown in Sicily

Leaf methanolic extracts of four wild Rose species (Rosa canina L., R. corymbifera Borkh., R. micrantha Borrer ex Sm and R. sempervirens L.) grown in Sicily were analysed in order to evaluate differences among indigenous roses which could be used such as source of bioactive compounds and natural antioxidants. Leaves were harvested during two different periods (June and October) and their morphological characteristics were described. Leaf content of chlorophylls, total anthocyanins, total flavonoids, total polyphenols (Folin-Ciocalteu method) and antioxidant activity (DPPH method) were determined. Results showed that the contents of chlorophylls and carotenoids were higher in leaves of all species harvested in June than in those harvested in October. On the contrary, total anthocyanins of R. micrantha and R. corymbifera leaves were higher in October. Total polyphenol content was higher in leaves of all species were harvested in October. No difference in total flavonoids content was recorded between the two harvest periods but only among the four species. Antioxidant activity was generally high in leaf extracts of all species in both periods and, particularly, in R. micrantha leaves harvested in June. These outcomes seem to support the assessment that leaves harvested from some Sicilian wild roses may be used as promising source of healthy compounds and that their content varies with the species and harvest period.