Sicilian myrtle diversity: evaluation of leaf total phenols content and antioxidant properties

Myrtle (Myrtus communis L.) is an aromatic plant spontaneously growing andincreasingly cultivated in Mediterranean area. Recently, interest on myrtle plant isgrowing due to the pharmacological and antioxidant properties since myrtle leavesare important sources of phenolic and antioxidant compounds with health-promotingeffects. Plant genotype is the primary factor affecting antioxidant activity and phenolcontent. For this reason, a core collection of local selected myrtle accessions fromSicily was evaluated with the aim to identify genotypes with high antioxidant value.Thirty-six myrtle individuals belonging to seven populations were studied for leaftotal phenols, tannins and antioxidant activity. Results of quantitative determinationof total phenols, tannins and antioxidant activity measured with two protocols (DPPHand ABTS radical scavenging activity) revealed a high variability of myrtle genotypesfor these parameters. Leaves of the accession MTR11 belonging to Scopello populationhad the highest total phenol content as catechin equivalents (5495 mg CE 100 g-1 dw)and the highest antioxidant activity (DPPH: 53.7 mmols Trolox 100 g-1 dw; ABTS: 61.6mmols Trolox 100 g-1 dw). On the contrary, the lowest phenols content (1540.7 mg CE100 g-1 dw) and the lowest antioxidant activity (DPPH: 13.9 mmols Trolox 100 g-1 dw;ABTS: 16.7 mmols Trolox 100 g-1 dw) were determined in the genotype MTR7belonging to Zingaro population. The concentration of tannins in the leaves of myrtleanalyzed ranged from 78.3 mg CE 100 g-1 dw to 356.9 mg CE 100 g-1 dw, in MRT7 ofZingaro and in 2MRT6 of Misilmeri populations respectively.