Phytochemical composition and antioxidant activity of high-lycopene tomato ( Solanum lycopersicum L.) cultivars grown in Southern Italy

Abstract

In this study, the antioxidant components and of six high-lycopene (Lyco 1, Lyco 2, HLY 02, HLY 13, HLY 18 and Kalvert) and one ordinary (Donald) tomato cultivars (cvs) grown simultaneously in an open-field of the Southern Italy were investigated. Lycopene, β-carotene, lutein, total phenols, flavonoids, ascorbic acid (AsA), dehydroascorbic acid (DHA) and total vitamin C (AsA + DHA) contents, as well as hydrophilic and lipophilic antioxidant activities (HAA and LAA) were determined. Significant differences were detected among tomato cvs in all studied antioxidant components, as well as in the antioxidant activity of their hydrophilic and lipophilic fractions. High-lycopene tomato cvs showed higher lycopene, β-carotene, HAA and LAA when compared to cv Donald. Cv HLY 18 showed the highest lycopene and β-carotene content with 232.9 mg/kg fresh weight (fw) and 19.4 mg/kg fw, respectively. Except for Kalvert, high-lycopene tomato cvs also obtained higher total vitamin C levels, with cv HLY 13 top ranking with an average of 352.8 mg/kg fw. LAA ranged from 133.5 μM Trolox/100 g fw in cv Donald to 540.1 μM Trolox/100 g fw in cv Lyco 2 and was significantly correlated to lycopene ( r = 0.53; p < 0.01) and β-carotene ( r = 0.56; p < 0.01) contents. A variation between 2.7- and 4.0-fold was found in LAA of high-lycopene tomato cvs compared to Donald. HAA was significantly correlated to the amount of DHA ( r = 0.61; p < 0.01) and total vitamin C ( r = 0.60; p < 0.01). Although these data require confirmation over a longer period of time, this investigation suggests a promising use of the high-lycopene tomato cvs for the production of tomatoes with higher nutritional quality.