Determination of interactions between nutrients in Oryza sativa L. naturally enriched in Se: tissue localization and characterization using XRF and atomic absorption
Selenium (Se) was first considerate as toxic, being today considered as an antioxidant trace mineral important for health and development. Lack of selenium in humans has been associate with high risk of mortality, deficient immune functions, cognitive decline, Keshman disease and white muscle disease. The growing demand for efficient, bioeconomic and sustainable strategies to increase Se content in rice is therefore justified, as is the study of the technical and nutritional implications inherent to its production and industrial processing for food products.
Se biofortification is a strategy that promotes nutrient enhancement in food crops and can increase nutrient uptake and accumulation in the human body. The technical itinerary was implemented, using two commercial varieties of rice (Ariete and Ceres) and two advanced lines of INIAV National Rice Genetic Improvement Program (OP1505 and OP1509). Five selenium concentrations were tested in the forms of selenate and sodium selenite by foliar application. It was verified using the EDXRF M4 Tornado ™ system, by spectral mapping, the preferential location of Se in rice. As such, it was found that Se was preferentially accumulated in the inner zone of rice grain. The contents of C, H and O, present in the different treatment concentrations, were also quantified. The average of Se biofortification index in variety Ceres was 16,3 % and the opposite was verified in variety Ariete, by atomic absorption.