Science

The metabolic mechanism of antioxidant properties of black rice is mapped

Worker's Daily - China Worker's Network Reporter Huang Zhewen Correspondent Wei Fei

The reporter learned from the Chinese Academy of Agricultural Sciences that the innovation team of the Institute of Crop Science of the Institute for the discovery and innovative use of excellent germplasm resources of rice has analyzed the metabolic mechanism of antioxidant properties of rice black rice, and revealed the differences of metabolites and metabolic pathways between colored brown rice and colorless brown rice, black rice and other colored brown rice at the metabolic level. Recently, the research results were published online in the journal Food Chemistry.

The metabolic mechanism of antioxidant properties of black rice is mapped

The appearance of brown rice in different colors, BR means black rice, RR means red rice, GR means glutinous rice, WR, means white rice (Photo by Institute of Agricultural Science, Chinese Academy of Agricultural Sciences)

According to the introduction, brown rice is the whole grain rice that still retains the seed coat and embryo after husking, which has higher nutritional value than refined rice. Compared with colorless brown rice, colored brown rice, especially black rice, generally contains more protein, trace elements, vitamins and other nutrients, and is rich in anthocyanins, phenolic acids, flavonoids, with strong antioxidant properties, but so far little research has been reported on the metabolic mechanism of antioxidant properties of black rice and other colored brown rice.

Using black rice, red rice, glutinous rice and white rice (all brown rice) created by the team as test materials, the study systematically resolved the differences in metabolites and metabolic pathways between colored rice and colorless rice, and black rice and non-black rice through extensive targeted metabolomics analysis. The differences in metabolites between black rice and glutinous rice and white rice, red rice and glutinous rice and white rice, and black rice and red rice were identified as 281, 305, 241, 267 and 265 metabolites, respectively. Among them, secondary metabolites accounted for more than 50% of the differential metabolites between black rice and glutinous rice and white rice, and secondary metabolites accounted for more than 40% of the differential metabolites between red rice and glutinous rice and white rice.

It was found that these secondary metabolites are mainly flavonoids, phenolic acids and alkaloids, which have strong antioxidant activity and have anti-aging, regulation of body functions and disease prevention effects. Further analysis of 117 differential metabolites specific to black rice showed that the main ones were 58 flavonoids and 25 phenolic acids, and their main significant enrichment pathways were biosynthesis of flavonoids, biosynthesis of anthocyanins, biosynthesis of flavonoids and flavonols.

This study reveals the differences in metabolites and metabolic pathways among different types of brown rice, and provides a scientific basis for functional rice breeding.