Lipid components, fatty acid distributions of triacylglycerols and phospholipids in rice brans

Hiromi Yoshida; Takaaki Tanigawa; Naoko Yoshida; Isoko Kuriyama; Yuka Tomiyama; Yoshiyuki Mizushina

doi:10.1016/j.foodchem.2011.04.102

Lipid components, fatty acid distributions of triacylglycerols and phospholipids in rice brans

Food Chem. 2011 Nov 15;129(2):479-484. doi: 10.1016/j.foodchem.2011.04.102. Epub 2011 May 4.

Authors

Hiromi Yoshida¹, Takaaki Tanigawa², Naoko Yoshida³, Isoko Kuriyama², Yuka Tomiyama², Yoshiyuki Mizushina⁴

Affiliations

¹ Department of Nutritional Science, Kobe Gakuin University, Kobe, Hyogo 651-2180, Japan; Cooperative Research Center of Life Sciences, Kobe Gakuin University, Kobe, Hyogo 650-8586, Japan. Electronic address: yoshida@nutr.kobegakuin.ac.jp.
² Department of Nutritional Science, Kobe Gakuin University, Kobe, Hyogo 651-2180, Japan.
³ Department of Biochemical Sciences, College of Sciences, Ritsumeikan University, Kusatu, Shiga 525-8577, Japan.
⁴ Department of Nutritional Science, Kobe Gakuin University, Kobe, Hyogo 651-2180, Japan; Cooperative Research Center of Life Sciences, Kobe Gakuin University, Kobe, Hyogo 650-8586, Japan.

PMID: 30634254
DOI: 10.1016/j.foodchem.2011.04.102

Abstract

Endogenous tocochromanols in extracted lipids from rice brans of the five cultivars were determined by high-performance liquid chromatography, and were investigated in relation to the fatty acid (FA) distribution of triacylglycerols (TAG) and phospholipids (PL). The dominant tocols were α-tocopherol and γ-tocotrienol, followed by α-tocotrienol and with much smaller amounts of γ-tocopherol and δ-tocotrienol. The lipids of these rice brans comprised mainly TAG (80.6-86.0wt.%), free FA (4.2-9.0wt.%), and phospholipids (5.5-6.7wt.%), whilst other components were also detected in minor proportions (0.2-2.1wt.%). The PL components included phosphatidyl choline (31.8-46.8wt.%), phosphatidyl ethanolamine (25.0-38.9wt.%) and phosphatidyl inositol (20.2-23.2wt.%). Comparison of these different cultivars showed, with a few exceptions, no significant differences (P>0.05) in FA distribution. FA distribution of TAG among the five cultivars was evident in the rice brans: unsaturated FA were predominantly concentrated at the sn-2 position and saturated FA primarily occupying the sn-1 or sn-3 position. These results suggest that the tocopherol content, lipid component, and FA distribution in rice brans are not dependent on the cultivation areas during the growing season.

Keywords: Fatty acid compositions; Phospholipids; Rice bran lipids; Tocopherols; Tocotrienols; Triacylglycerols.