Dale Bumpers National Rice Research Center, Agricultural Research Service, U.S. Department of Agriculture, 2890 Highway 130 East, Stuttgart, Arkansas 72160, USA.
J Agric Food Chem. 2012 Sep 12;60(36):9151-61. doi: 10.1021/jf3025453. Epub 2012 Aug 27.
We determined the phenolic, anthocyanin, and proanthocyanidin content of three brown, purple, and red rice brans isolated from different rice varieties using HPLC-PDA with the aid of 27 standards of known structure and matching unknown peaks to a spectral library of known compounds. Antioxidative capacities were determined by DPPH and ORAC and cell-inhibiting effects using an MTT assay. Based on the calculated IC(50) values, the light-brown bran had no effect, the purple bran exhibited a minor effect on leukemia and cervical cancer cells, and the red bran exhibited strong inhibitory effects on leukemia, cervical, and stomach cancer cells. High concentrations of protocatechuic acid and anthocyanins in purple bran and proanthocyanidins in red bran were identified. The red bran was further fractionated on a Sephadex column. Fraction 3 rich in proanthocyanidin oligomers and polymers had the greatest activity. Red bran has the potential to serve as a functional food supplement for human consumption.
我们使用 HPLC-PDA 结合 27 种已知结构的标准品和匹配未知峰的光谱库，确定了三种来自不同水稻品种的棕色、紫色和红色米糠的酚类、花青素和原花青素含量。抗氧化能力通过 DPPH 和 ORAC 以及 MTT 测定细胞抑制作用来确定。根据计算出的 IC(50) 值，浅棕色米糠没有作用，紫色米糠对白血病和宫颈癌细胞有轻微作用，而红色米糠对白血病、宫颈癌和胃癌细胞有强烈的抑制作用。鉴定出紫色米糠中高浓度的原儿茶酸和花青素以及红色米糠中原花青素低聚物和聚合物。富含原花青素低聚物和聚合物的红色米糠级分 3 具有最大的活性。红色米糠有可能作为功能性食品补充剂供人类食用。
