Protective effects of unsaponifiable matter from rice bran on oxidative damage by modulating antioxidant enzyme activities in HepG2 cells

Hyeonmi Ham, Sung Won Yoon, In-Hwan Kim, Jieun Kwak, Jeom Sig Lee, Heon sang Jeong, Junsoo Lee

Research output: Contribution to journalArticle

21 Citations (Scopus)


Rice bran is a byproduct of the rice milling process. It contains high levels of bioactive phytochemicals such as phytosterols, tocopherols, tocotrienols, γ-oryzanol, triterpene alcohol, and other minor compounds, which have antioxidant and health-promoting properties. The objective of this study was to evaluate theprotective effect of unsaponifiable matter (USM) from rice bran against oxidative damages induced by tert-butyl hydroperoxide (TBHP) in HepG2 cells. Levels of cellular reactive oxygen species (ROS), cellular lipid peroxidation, reduced glutathione (GSH), and antioxidant enzyme activity were evaluated as biomarkers of the cellular oxidative status. HepG2 cells were pretreated with various concentrations of USM (0-100μg/mL) for 12h prior to TBHP exposure. Pretreatment of HepG2 cells with USM prevented the cell damage induced by TBHP in a dose-dependent manner. Cellular generation of ROS, formation of malondialdehyde (MDA), and depletion of GSH induced by TBHP were prevented by pretreatment with USM. In addition, treatment with TBHP increased the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. However, pretreatment with USM significantly reduced the activities of these enzymes. These results indicate that treatment of HepG2 cells with USM confers significant protection against oxidative damage by modulating ROS production, GSH levels, and antioxidant enzyme activity.

Original languageEnglish
Pages (from-to)602-608
Number of pages7
JournalLWT - Food Science and Technology
Issue number2
Publication statusPublished - 2015 May 1



  • Antioxidant enzymes
  • HepG2 cells
  • Oxidative stress
  • Rice bran
  • Unsaponifiable matter

ASJC Scopus subject areas

  • Food Science

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