Variations in bran carotenoid levels within and between rice subgroups

Plant Foods Hum Nutr. 2010 Dec;65(4):358-63. doi: 10.1007/s11130-010-0196-y.

Abstract

Rice (Oryza sativa L.) is a major grain in the human diet and carotenoids are valuable antioxidants. However, little is known about varietal differences in the carotenoid contents of the rice bran. The objective of this study is to determine the relative differences in bran carotenoid levels among all the five subgroups of rice. Measurements were made by a recently described, rapid non-destructive fluorescence quenching method. Confirmation by high performance liquid chromatography (HPLC) after solvent extraction of the bran indicated that the major carotenoid was lutein. Our data showed that carotenoid levels were stable over 10 years of storage. Tropical japonica rice, the most consumed subgroup in the United States, tended to have the lowest levels of carotenoids in the bran while temperate japonicas had the highest. These differences in carotenoid content may open up new opportunities for identifying or breeding rice varieties with higher nutritional value.

MeSH terms

  • Carotenoids / analysis*
  • Lutein / analysis
  • Oryza / chemistry*
  • Oryza / classification*
  • Spectrometry, Fluorescence

Substances

  • Carotenoids
  • Lutein