Vitamin E profile in rice (Oryza sativa L.) seeds grown and commercialized in Costa Rica

Abstract

Introduction. Rice (Oryza sativa L.) is one of the most consumed cereals worldwide, the indica and japonica subspecies are the most cultivated. The vitamin E present in rice has a high antioxidant activity that contributes to extend the longevity of its seeds. Its quantification allows to know the nutritional contribution of this vitamin. Objective. To analyze the vitamin E profile in seeds of indica (registered commercial, aromatic, promising in development) and japonica subspecies of rice (O. sativa L.), consumed in Costa Rica. Materials and methods. Twenty-seven materials grown in the Chorotega and Brunca regions of Costa Rica, harvested in 2020 were analyzed. Vitamin E was quantified by ultra-high performance liquid chromatography coupled to triple quadrupole mass detection with chemical ionization source at atmospheric pressure at the Centro para Investigaciones en Granos y Semillas (CIGRAS), Universidad de Costa Rica, in 2021. Results. In the vitamin E profile, a characteristic clustering was obtained for the japonica samples, which was opposite to that presented by the indica samples. The majority compounds were γ-tocotrienol, α-tocopherol, and γ-tocopherol, the range of total vitamin E concentration was 5.50 to 33.20 μg g-1, where the japonica subspecies reported the lowest amount (6.30-8.80 μg g-1), while the Nayuribe sample, belonging to the registered commercial indica subspecies, obtained the highest concentration (33.20 ± 7.40 μg g-1). Conclusion. Although the analyzed subvarieties are phylogenetically from the same species, the significant differences found in the nutritional intake of vitamin E may be due to intrinsic characteristics of each subspecies. The significantly high vitamin E content in the Nayuribe sample showed that it is possible to find stocks for a high vitamin E content among the varieties analyzed.