Bioactive compounds and antioxidative activity of colored rice bran

• Published in: Yàowu shi͡p︡in fenxi 2016-07, Vol.24 (3), p.564-574
• Main Authors: Huang, Yu-Ping, Lai, Hsi-Mei
• Format: Article
• Language: English
• Subjects: Acids; Anthocyanins; Antioxidants; antioxidative activity; Bioactive compounds; Biological activity; Biphenyl Compounds; bran; Chromatography, High Pressure Liquid; Color; colored rice; Dietary fiber; Ethanol; Flavonoids; High performance liquid chromatography; Ionization; Liquid chromatography; Mass spectrometry; Mass spectroscopy; Original; Oryza; Oryza longistaminata; Phenolic acids; Phenols; Phenylpropionates; Plant Extracts; Proanthocyanidins; protocatechualdehyde; Rice; Rice bran; Seeds; Tocopherol; Vitamin E
• ISSN: 1021-9498; 2224-6614
• DOI: 10.1016/j.jfda.2016.01.004

The profiles of bioactive compounds (including phenolics and flavonoids in free and bound fractions, anthocyanins, proanthocyanidins, vitamin E, and γ-oryzanol) of outer and inner rice bran from six colored rice samples collected from local markets were investigated. Proanthocyanidins could only be detected in red rice bran but not in black rice bran. The free fraction of the extracts dominated the total phenolics (72–92%) and the total flavonoids (72–96%) of colored rice bran. Most of the phenolic acids (83–97%) in colored rice bran were present in the bound form. Protocatechualdehyde was identified for the first time in the bound fraction of red rice bran by high performance liquid chromatography-photodiode array/electrospray ionization tandem mass spectrometry. The antioxidative activities of the free fraction of the colored rice bran were attributed to the proanthocyanidins in red colored rice and anthocyanins in black rice, while that of the bound fraction was mainly due to the phenolic acids. [Display omitted]