Bioactive compounds and antioxidant activity of organically grown tomato (Solanum lycopersicum L.) cultivars as affected by fertilization

In this study, the antioxidant properties of two tomato cultivars Firenze and Rio Grande grown organically in an open-field under different combinations of organic fertilizer sources were investigated, lycopene, total phenols and flavonoids contents, as well as lipophilic, hydrophilic and total antioxidant activities were determined. Significant differences were found between tomato cvs in lycopene and antioxidant activity. Firenze cv showed higher lycopene, lipophilic, hydrophilic and total antioxidant activities when compared to cv Rio Grande. On the other hand, even though antioxidant activity was affected by the different organic fertilizer treatments, tomato bioactive compounds were not affected whatever the cv. LAA ranged from 123.8 μM Trolox/100 g fresh weight (fw) in cv Rio Grande to 153.4 μM Trolox/100 g fw in cv Firenze and was significantly correlated to lycopene (r = 0.45; p < 0.05) content. HAA ranged from 81.5 μM Trolox/100 g fw in cv Rio Grande to 101.3 μM Trolox/100 g fw in cv Firenze and was not significantly correlated to total phenols and flavonoids contents. Although these data require confirmation over a longer period of time, this investigation emphasizes the satisfactory organic tomato antioxidant attributes.

► We report the antioxidant properties of organically grown tomato cultivars.
► Cultivar affects antioxidant properties of organically grown tomato.
► Fertilizer treatments affect organic tomato antioxidant activity.
► Organic tomato antioxidant attributes were satisfactory.