COMPARATIVE STUDIES ON MAJOR NUTRITIONAL COMPONENTS OF RICE WITH A GIANT EMBRYO AND A NORMAL EMBRYO

Abstract

Two subspecies of rice, Oryza sativa ssp. indica rice mutant II-gel and O. sativa ssp. japonica rice mutant XS-gel, were characterized by an enlarged embryo compared to their wild types. Significant increases in crude lipid content; crude protein content; vitamin Bl (V B1 ); vitamin B2; vitamin E (V E ); essential amino acids such as arginine, aspartic acid, glutamic acid, lysine and methionine and mineral elements such as Ca, Fe, Mg, K, P and Zn were detected in rice with a giant embryo (ge). The nutrients in the brown rice changed drastically after pre-germination. The dramatic nutrient enrichments were observed. in the pre-germinated brown rice with a ge. The six major enhanced nutrients were γ-amino-butyric acid (GABA), lysine, Mg, V B1 , V E and Ca, and the amounts were 7.3 and 4.7 times enriched for GABA, 3.4 and 3.0 times for lysine, 2.9 and 2.7 times for Mg, 2.8 and 2.5 times for V B1 , 2.5 and 2.2 times for V E and 2.1 and 1.8 times for Ca, respectively, relative to those in the brown rice with a normal embryo. The results suggest that a ge can be used as a phenotypic marker for food processors to select rice enriched with certain nutritional components, and that the application of giant-embryo rice would help develop cultivars with an improved nutritional content.