Ti Huihui, Li Qing, Zhang Ruifen, Zhang Mingwei, Deng Yuanyuan, Wei Zhencheng, Chi Jianwei, Zhang Yan
Sericultural and Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, PR China.
Sericultural and Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, PR China.
Food Chem. 2014 Sep 15;159:166-74. doi: 10.1016/j.foodchem.2014.03.029. Epub 2014 Mar 17.
This study quantified free and bound phytochemicals and their antioxidant activity in the endosperm and bran/embryo of different indica rice varieties. Phytochemicals mainly existed as free form in the bran/embryo and as both free and bound forms in the endosperm. The average values of total phenolic content, flavonoid content, FRAP, ABTS and ORAC values in the bran/embryo were 3.1, 10.4, 8.2, 11.2 and 11.4 times higher than those in the endosperm, respectively. In whole brown rice, the bran contributed 59.2%, 53.7%, 47.7%, 55.5% and 56.9% of total phenolics, flavonoids, FRAP, ABTS and ORAC values, respectively. Seven individual phenolics (gallic, protocatechuic, chlorogenic, caffeic, syringic, coumaric and ferulic acids) were detected with most coumaric and ferulic acids in the bran. All measurements exhibited varietal differences. These findings provide important information for improving human health by encouraging the consumption of whole brown rice and its use in food product development.
本研究对不同籼稻品种胚乳和麸皮/胚中的游离和结合态植物化学物质及其抗氧化活性进行了定量分析。植物化学物质在麸皮/胚中主要以游离形式存在，在胚乳中则以游离和结合两种形式存在。麸皮/胚中总酚含量、黄酮含量、铁还原抗氧化能力（FRAP）、2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸（ABTS）和氧自由基吸收能力（ORAC）的平均值分别比胚乳中的高3.1倍、10.4倍、8.2倍、11.2倍和11.4倍。在糙米中，麸皮分别占总酚、黄酮、FRAP、ABTS和ORAC值的59.2%、53.7%、47.7%、55.5%和56.9%。检测到七种单一酚类物质（没食子酸、原儿茶酸、绿原酸、咖啡酸、丁香酸、香豆酸和阿魏酸），其中麸皮中香豆酸和阿魏酸含量最高。所有测量结果均表现出品种差异。这些发现为鼓励食用糙米及其在食品开发中的应用以改善人类健康提供了重要信息。
