The purpose of this study is to compare the potentials to exhibit biologically active antioxidant actions between white rice (WR) and brown rice (BR) in in vitro assays and a cellular model. The Trolox equivalent (TE) per 1 mg ethanol extract of WR for the 1,1-diphenyl-2-picrylhydrazyl assay was slightly higher than that of BR, whereas the TE per 1 g whole WR was much lower than that for BR. This tendency was very comparable to those for the oxygen radical absorbance capacity and total polyphenol content. Both of the ethanol extracts also similarly suppressed the hydrogen peroxide-induced cytotoxicity and enhanced the gene expression of drug-metabolizing enzymes. Based on the α-tocopherol quantity, its contribution to the cytoprotective effect of the rice extracts is very limited. Taken together, the ethanol extract of WR might be a qualitatively, but not quantitatively, equivalent source of antioxidative phytochemicals to that of BR.

中文翻译：

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白米乙醇提取物作为抗氧化剂来源，定性而非定量等同于糙米。

本研究的目的是比较白米 (WR) 和糙米 (BR) 在体外测定和细胞模型中表现出生物活性抗氧化作用的潜力。对于 1,1-二苯基-2-苦基肼测定，每 1 mg WR 乙醇提取物的 Trolox 当量 (TE) 略高于 BR，而每 1 g 整个 WR 的 TE 远低于 BR。这种趋势与氧自由基吸收能力和总多酚含量的趋势非常相似。两种乙醇提取物也同样抑制过氧化氢诱导的细胞毒性并增强药物代谢酶的基因表达。基于 α-生育酚的数量，它对大米提取物的细胞保护作用的贡献非常有限。综上所述，WR 的乙醇提取物可能是一种定性的，