A new feruloyl glyceride from the roots of Asian rice (Oryza sativa)

Abstract Oryza sativa L., Poaceae, is the most important staple food in the world and provides food for more than half of the world's population. The roots of O. sativa have been used as a traditional medicine in Korea. As part of our continuing efforts to explore structurally new compounds from Korean natural resources, two feruloyl glycerides, 2-O-(E)-feruloyl glyceride (1) and 2-O-(Z)-feruloyl glyceride (2), which is a new compound, together with one known flavonoid, 8-hydroxyacacetin (3), were isolated from the ethanolic extract of the roots of O. sativa using an LC/MS-guided isolation method. The chemical structure of compound 2 was elucidated based on comprehensive 1D and 2D NMR spectroscopic experiments and HR-ESIMS. This study represents the first report of feruloyl glycerides (1-2) identified in O. sativa. In addition, the identification of compound 3 is reported from Asian rice (O. sativa) for the first time. The cytotoxic activities of the isolates 1-3 were evaluated by determining their inhibitory effects on A2780 human ovarian carcinoma cells.

Molecular characterization and genetic diversity of different genotypes of Oryza sativa and Oryza glaberrima

Background: Availability of related rice species is critical for rice breeding and improvement. Two distinct species of domesticated rice exist in the genus Oryza: Oryza sativa (Asian rice) and Oryza glaberrima (African rice). New rice for Africa (NERICA) is derived from interspecific crosses between these two species. Molecular profiling of these germplasms is important for both genetics and breeding studies. We used 30 polymorphic SSR markers to assess the genetic diversity and molecular fingerprints of 53 rice genotypes of O. sativa, O. glaberrima, and NERICA. Results: In total, 180 alleles were detected. Average polymorphism information content and Shannon's information index were 0.638 and 1.390, respectively. Population structure and neighbor-joining phylogenetic tree revealed that 53 genotypes grouped into three distinct subpopulations conforming to the original three groups, except three varieties (IR66417, WAB450-4, MZCD74), and that NERICA showed a smaller genetic distance from O. sativa genotypes (0.774) than from O. glaberrima genotypes (0.889). A molecular fingerprint map of the 53 accessions was constructed with a novel encoding method based on the SSR polymorphic alleles. Ten specific SSR markers displayed different allelic profiles between the O. glaberrima and O. sativa genotypes. Conclusions: Genetic diversity studies revealed that 50 rice types were clustered into different subpopulations whereas three genotypes were admixtures. Molecular fingerprinting and 10 specific markers were obtained to identify the 53 rice genotypes. These results can facilitate the potential utilization of sibling species in rice breeding and molecular classification of O. sativa and O. glaberrima germplasms.