Antioxidant activity and general fruit characteristics in different ecotypes of Corbarini small tomatoes.

Sixteen ecotypes of Corbarini small tomatoes were studied. The antioxidant activity was evaluated with the DMPD (N, N-dimethyl-p-phenylenediamine) method in the water-soluble fraction (S-AA) and with the ABTS [2, 2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)] method in the water-insoluble fraction (I-AA). S-AA and I-AA were strongly related to each other, varying to a large extent between the ecotypes considered. They were also significantly correlated with fruit weight, total solids, and refractive index. The combination of the latter variables (by multiple regression analysis) accounted for 36% and 44% of the total variability of S-AA and I-AA, respectively. Moreover, when the ecotypes were subdivided according to their shape (round, pear-shaped, oval, and long), S-AA and I-AA were both significantly higher in round tomatoes and lower in the long ones. In conclusion, the antioxidant activity varies to a considerable extent between different ecotypes of Corbarini small tomatoes. These differences are related to shape and some other fruit characteristics.