Caratterizzazione del profilo fenolico di alcune pesche e nettarine

Natural products, commonly known as "phytochemicals", are presently arousing great attention in the scientific community for their nutritional and dietetic value as antioxidant molecules. Fruits and vegetables are the principle sources of antioxidant compounds and, among these molecules, phenolic compounds are considered as the more actives and powerful phytochemicals. Quality and quantity of phenolic compounds are both relevant aspects to investigate in order to evaluate the potential antioxidant property of a specific fruit specie. Information on peaches phenolics composition, specifically in relation to the large number of cultivars actually present on the market, are still incomplete. This research therefore aimed to develop a suitable methodology for the analysis of phenolic compounds of peaches and nectarines common in the Italian Prunus persica cultivar scenario. Yellow and white pulp peaches (cv Redhaven and cv Fidelia) and nectarines (cv Stark Red Gold and cv Silver Rome) were compared for their phenolic contents at harvest stage and the potential intake of these molecules were estimated for the different fruit tissues. Qualitative differences among skin and pulp tissues weredetected. In detail, specific chromatografic peaks were characteristic of skin samples only, therefore showing the presence of a certain number of tissue-specific phenolic compounds (quercetin derivatives and anthocyanins, for instance). As regarding the average total phenolics concnetrations of the different analysed cultivars, values ranged from 3 to 4 mg/g DW (skin) and from 1 to 1.5 mg/g DW (pulp), with the relevant exception of cv Silver Rome (a nectarine) that showed a clearly higher concentrations. Skin tissue concentrations were approximately 3 fold higher than in pulp tissue, showing therefore the putative nutritional difference of a peach consumed after peeling or as a whole.