Characterization of the phenolic constituents and the antioxidant activity of cytisus multiflorus

The specific interest in naturally occurring antioxidants has lead to an exponential investigation of many traditional medicinal plants, as they are potential candidates for finding new therapeutic and supplementary health products. Cytisus multiflorus, also known as White Spanish Broom, is a leguminous shrub native from Iberian Peninsula that is u sed in folk medicine mainly due to its diuretic and anti-inflammatory properties. Still, despite its common usage for centuries, this plant has been far less studied than other species of the same genus. This study aimed to determine the phenolic composition and to evaluate the antioxidant capacity of Cytisus multiflorus. For that, an ethanolic extract was prepared and its total phenolics and flavone contents were determined. The antioxidant activity was accessed by measuring the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging potential. Also, the extract was fractionated by reversed-phase HPLC and the major phenolic compounds of each fraction were identified by ESI-MS and MSn analysis, in order to establish the specific phenolic profile of the plant. The total amount of phenolic compounds and of flavones accounted for 140 mg/g and 47 mg/g of the ethanolic extract from Cytisus multiflorus, respectively. Also, it exhibited a high antioxidative capacity, with an EC50 value of 29,7 μg/ml. Moreover, the interpretation of the fragmentation pathways under ESI-MS/MS of the collected HPLC fractions allowed concluding that the main phenolic compounds in the plant included chrysin and some glycoside derivatives of luteonine and quercetin. Thus, the overall results suggest that the phenolic extract of the Cytisus multiflorus can be claimed as a good source of natural antioxidants.