Effect of the Fe-HBED chelate on the nutritional quality of tomato fruits

Despite active debate about Fe fortification of food due to Fe fertilization, not much is known about influence of Fe availability on fruit quality, including tomatoes. Thus, our goal was to study the effect of Fe-HBED chelate on the nutritional quality of tomato (Solanum lycopersicum L.) fruits. The results showed that supraoptimal Fe-HBED supplementation caused cultivar-dependent detrimental changes in elemental status of fruit pericarp. Following Fe supplementation significant increases in xanthophylls and beta-carotene contents were recorded. The results showed that Fe supplementation did not strongly interfere with metabolism of amino acids and other secondary metabolites, as contents of free amino acids, lycopene, soluble phenolics and flavonoids were not significantly affected. Moreover, differences in further lycopene trafficking into different branches of secondary metabolism (biosynthesis of carotenoids and xanthophylls) were observed. The data point out the important impact of Fe supplementation on nutritional quality (elemental composition and content of carotenoids and xanthophylls) of tomato fruits and warn against usage of Fe-oversupplied soil or Fe-enriched water for cultivation of tomatoes.