Chemotype and genotype combined analysis applied to tomato (Lycopersicon esculentum Mill.) analytical traceability

A large number of fresh fruits and vegetables are primary sources of antioxidants; tomato (Lycopersicon esculentum Mill.) is accepted worldwide as a significant source of antioxidant functional compounds (vitamin C, lycopene, rutin). Many cultivars and hybrids of tomato, having different chemical and nutritional characteristics, are available on the market. Tomato cultivars for industrial processing are very different, not only in fruit characteristics (size, shape), but also in lycopene and antioxidant contents. The aim of this study was the chemotyping and genotyping of the tomato varieties Heinz 3402, Leader and Perfectpeel, (1) to evaluate the genetic traceability of these varieties, and (2) to determine whether their functional antioxidants compounds are useful markers of traceability. Principal component analysis (PCA) was first applied to the Random Polymorphic DNA (RAPD) fingerprints, confirming that this approach is a powerful identification method at intra-specific level. Heinz 3402 showed the highest antioxidant activity, followed by Perfectpeel and Leader varieties. Perfectpeel showed the lower lycopene content, while Leader and Heinz 3402 showed significantly higher values (13.68 and 15.78 mg/100 g, fresh weight, respectively). The highest rutin content was observed in Heinz 3402 (12.46 ± 0.69, mg/100 g, fresh weight), followed by Leader (7.87 ± 0.72) and Perfectpeel (2.70 ± 0.68). Antioxidant capacity was significantly correlated with the lycopene and rutin content. Finally, PCA was applied to chemotype data-sets, confirming both mineral content and functional antioxidant compounds as useful markers to unambiguously identify these high-lycopene content varieties.