Composition of phenolic compounds and antioxidant activity of different varieties of Mirabelle plum (P. domestica L. ssp syrica var cerea).

Abstract

The aim of this study was to evaluate the impact of Mirabelle plum variety, the part of the fruit (peel or pulp) and soil quality on composition of phenolic compounds and antioxidant activity of these fruits. Two varieties of Mirabelle plum fruits (yellow and red) were harvested in 2 places in the North of Poland - Lubawa and Debiniec - that varied in soil quality. Fruit peel and flesh were separated and tested individually. The composition of phenolic compounds was characterized using HPLC-DAD-MS, total antioxidant activity was assessed by spectrophotometric tests (ABTS, DPPH, FC). Antioxidant profiles were obtained using TLC and HPLC with post-column derivatization. All considered factors turned out to have strong impact on composition of phenolic compounds as well as on antioxidant activity. The highest content of phenolic compounds was observed in red Mirabelle plum peel from Debiniec (29.8 mg/g d.w.). Peels showed three to ten times higher content of phenolic compounds than pulp from corresponding fruits. Red fruits showed higher antioxidant activity than yellow fruits, because of their anthocyanins content. Both red and yellow varieties harvested in Debiniec turned out to be richer source of phenolic compounds than the same varieties harvested from Lubawa.