Biofortification of vegetable crops with silicon for human nutrition

Introduction. A healthy and balanced diet prevents the occurrence of many age-related diseases. On the basis of this claim, new types of food, defined novel foods, such as potato selenium, carrot, onion, tomato iodine, have been developed. Objectives. Considering the biological activities induced by silicon (antioxidant activity, increased mineralization of bone, development of connective tissue), the aim of this study was to obtain different silicon biofortificated vegetables (Tatsoi, Mizuna, Portulaca, Bietola and Cicoria) used as mix for the IV gamma product (ready to use), in order to have an useful food for post-menopausal women. In addition, the assessment of bioaccessibility of crops, by in vitro gastro-digestion process, and antioxidant activity on human intestinal cell line, were carried out. Methodology. For the biofortified plants production, a soilless system able to monitoring the effective absorption of the silicon was used. The plants were digested using the protocol described by Ferruzzi et al., (2001) in order assess the bioaccessibility. The antioxidant activity of digesta samples was evaluated on Caco-2 cell line using DCFH-DA probe. Results and conclusions. No modifications on the production and/or quality of the plant were found. A species-related accumulation of silicon was recorded with an mean value of 130 mg/kg fresh weight respect to average value blank of 22 mg/Kg. In addition, the silicon was bioaccessible in a range from 36 to 75% in relation to vegetable species studied. The biofortification significantly (p<0.001) improved the antioxidant activity induced by crops.