Polyphenols profile and antioxidant activity of skin and pulp of a rare apple from Marche region (Italy)

BACKGROUND: Apples are an important source of polyphenols in the human diet and the consumption of this fruit has been linked to the prevention of degenerative diseases. RESULTS: Catechins, procyanidins, hydroxycinnamic acids, flavonol glycosides, dihydrochalcone glycosides and one anthocyanin: cyanidin-3-O-galactoside, were identified both in the peel and pulp. Procyanidins, catechins and flavonols represent the main constituents of peel. Concerning the antioxidant activity, in the reduction of the stable DPPH radical and in the inhibition of lipid peroxidation, the ethanolic extracts of red peel and red pulp showed a good similar activity comparable to ascorbic acid in the DPPH test and about ten times more active than BHT in the lipoxygenase test, and were much more active than aqueous extracts. The ORAC value of red pulp aqueous extract resulted comparable to that of red berries: vaccinium, rubus and ribes, foods appreciated for their health value. CONCLUSION: This apple contains an appreciable amount of polyphenols also in the flesh; this variety with red flesh can also be useful for researchers engaged in apples varietal innovation in addition to being used as food apple.