Vegetable sprouts enriched with iron: Effects on yield, ROS generation and antioxidative system

Abstract Iron(Fe) deficiency is a widespread nutritional disorder affecting human health and interest is therefore growing in producing plants enriched with this element as a dietary source of Fe. Owing to high nutritional value and improved bioaccessibility of essential elements, sprouts are promising targets for enrichment. In this study an attempt was made to evaluate the effects of enriching vegetable sprouts with Fe on: (i) the concentration of Fe and other ions, (ii) biomass accumulation, (iii) the levels of ROS and (iv) the activity/content of the constituent elements of enzymatic and non-enzymatic anti-oxidative systems. The germination of sprouts in the presence of Fe generated a considerable increase in the concentration of this element, especially in alfalfa (2.3-fold increase). Sprouts enriched with Fe were not depleted of other valuable ions, but their biomass accumulation generally slightly decreased, which was particularly pronounced in the sprouts of crucifers. A higher Fe concentration promoted generation of ROS and simultaneously increased activity of antioxidative enzymes (APX, CAT and GR), and greater contents of phenolic compounds and ascorbic acid. These new findings demonstrate that in the elaboration of enrichment technology, attention must be paid to the possibly elevated levels of ROS in the food products obtained. Of the sprouts tested, radish and alfalfa grown in the presence of Fe in concentrations 12 and 24 mg/L proved to be the most suitable for enrichment with Fe as they accumulated considerable amounts of Fe at still acceptable levels of accumulated biomass and relatively low generation of ROS.