Phenolic profile of wild fruits of Rosa micrantha ex Sm. and Rosa canina L. from Northeast Portugal

Phenolic metabolites are common constituents of fruits and vegetables, and t he interest of plant phenolic extracts derives from the evidence of their potent antioxidant activity and their wide range of pharmacologic properties including anticancer, antimicrobial and platelet aggregation inhibition activities [1]. Rosa canina L. fruits are eaten raw as snacks and possess prophylactic and therapeutic activities against a wide range of ailments. Rosa micrantha ex Sm. fruits are used to prepare homemade remedies that prevent or heal several human disorders and animal diseases [2] This study aimed to characterize the phenolic compounds present in the above mentioned wild fruits. The analysis of phenolic compounds was carried out by reversed-phase HPLC-DAD-ESI/MS, in order to establish the specific phenolic profile in two Rose species. R. canina and R. micrantha presented a very similar profile being detected different classes of flavonoids, but no phenolic acids were found in these samples. The highest flavone/ols (11.16 mg/100g), flavan-3-ols and galloyl derivates (19.90 mg/100g), and anthocyanins (1.19 mg/100g) content were found in R. micrantha fruits. Taxifolin pentoside was the most abundant flavanonol found in these fruits and represented 1.18 mg/100 mg for R. canina and 2.68 mg/100 g for R. micrantha. Methyl gallate hexoside was only found in R. micrantha (2.45 mg/ 100g). (+)-Catechin was the most abundant flavan-3-ol found in the samples (R. canina 3.59 mg/100 g and R. micrantha 4.93 mg/ 100g), whereas cyanidin 3-D-glucoside was the only anthocyanin detected (R. canina 0.68 μg/100 g and R. micrantha 1.19 μg/100 g). The studied fruits may have great potential for food industries as a source of colors and flavors, as well as bioactive molecules such as phenolic compounds for dietary supplements or functional foods.FCT and COMPETE/QREN/EU: strategic project PEst-OE/AGR/ UI0690/2011 (CIMO); grant SFRH/BD/78307/2011 to R. Guimaraes, and "Compromisso para a Ciencia 2008" contract of L. Barros