ABSTRACT
Purpose@#The rice germ fraction is a better source of protein, lipid, and fiber than the rice endosperm. Furthermore, the rice germ is rich in bioactive phytochemicals such as γ-aminobutyric acid, tocopherols, tocotrienols, phytic acid, and so on. In this study, the phytosterol content and antioxidant activity of Keunnunjami germ (KG) or normal rice germ supplement were investigated in healthy adult rats. @*Methods@#In vitro, quantitative assessment of phytosterols, including β-sitosterol, campesterol, cycloartenol, and stigmasterol, was performed. Comparative antioxidant activities of 2 rice germs were measured based on DPPH radical scavenging activity, reducing power, and ABTS radical scavenging capacity. In vivo, male Spraque-Dawley rats (30-weeks-old) were randomly assigned a diet of normal control (NC, AIN-93M diet), AIN-93M diet supplemented with normal rice germ 3% (NG3), or AIN-93M diet supplemented with KG 3% (KG3) and fed for 8 weeks. @*Results@#KG contained significantly higher campesterol and stigmasterol contents and antioxidant activity than normal rice germ. The KG3 group exhibited significantly lower body weight gain as well as inguinal and total white adipose tissue weights. There were no significant differences in plasma glucose, insulin, C-peptide, or homeostasis model assessment of insulin resistance level among the 3 groups. The plasma tumor necrosis factor-α concentration was significantly lower while leptin, advanced oxidation protein products, and interleukin-6 showed downward trends in the KG3 group. In addition, the superoxide dismutase level of the KG3 group was significantly higher compared to the NC and NG3 groups. @*Conclusion@#This study indicates that KG can be considered as a valuable source of phytosterol components. Lastly, KG has strong antioxidant properties and may have potential to ameliorate elevation of proinflammatory cytokine production with age.
ABSTRACT
BACKGROUND/OBJECTIVES: Oxidative stress is a major cause of cancer. This study investigated the effects of the ethanol extracts from germinated and non-germinated Keunnunjami rice, a blackish-purple pigmented cultivar with giant embryo, on selected human cancer cell lines and on the antioxidant defense system of mice fed with a high-fat diet. MATERIALS/METHODS: High fat-fed mice were orally administered with either distilled water (HF) or extracts (0.25%, w/w) from brown (B), germinated brown (GB), Keunnunjami (K), and germinated Keunnunjami (GK) rice. RESULTS: In comparison with the brown rice extract, Keunnunjami extract showed higher anticancer effect against cervical and gastric cell lines but lower anticancer activity on liver and colon cancer cells. Mice from the HF group showed significantly higher lipid peroxidation and lower antioxidant enzyme activities than the control group. However, the oxidative stress induced by high-fat diet markedly decreased in B, GB, K, and GK groups as compared with the HF group. CONCLUSIONS: Germination may be an effective method for improving the anticancer and antioxidative properties of Keunnunjami rice and extracts from germinated Keunnunjami rice may serve as a therapeutic agent against cervical and gastric cancers and oxidative damage.