Reference Number: 462
Anthocyanins are naturally active substances. In this study, anthocyanins from black rice were obtained by membrane filtration and column chromatography separation. Five anthocyanin monomers in black rice extract were identified by HPLC-MS/MS, and the major anthocyanin monomer (cyanidin-3-glucoside, C3G) was purified by preparative HPLC (Pre-HPLC). The proliferative effects of the anthocyanins on Bifidobacteria and Lactobacillus were investigated by determining the media pH, bacterial populations and metabolic products. After anaerobic incubation at 37 °C for 48 h, not only the pH of the media containing C3G was lower than that of the extract of black rice anthocyanin (BRAE), but the numbers of both Bifidobacteria and Lactobacillus were also significantly increased. Furthermore, hydroxyphenylpropionic, hydroxyphenylacetic, and hydroxybenzoic acids and other metabolites were detected by GC-MS in vitro. Our results revealed that the anthocyanins and anthocyanin monomers from black rice had prebiotic activity and they were metabolized into several small molecules by Bifidobacteria and Lactobacillus.
Significance of this study to the baker:
Black rice (Oryza sativa L.) is included within our botanical blends.
Black Rice is a crop from the plant rice with a long cultivation time and is mostly cultivated in China and other Asian countries. Its colour stems from the abundant level of anthocyanins located in the aleurone layer of the black rice. This have been identified as highly effective antioxidants. This laboratory study provides evidence that the anthocyanins found in Black Rice increase levels of the beneficial gut bacteria, Bifidobacteria and Lactobacillus. It explains how these bacteria feed on the anthocyanins as prebiotics and their fermentation in the gut produces further metabolites to promote the health of our gastrointestinal health. We do however need further human trials.