Sun Guo-Xin, Van de Wiele Tom, Alava Pradeep, Tack Filip M G, Du Laing Gijs
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, the Chinese Academy of Sciences, Beijing, China.
Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, Ghent, Belgium.
J Sci Food Agric. 2017 Aug;97(11):3540-3545. doi: 10.1002/jsfa.8208. Epub 2017 Feb 7.
As an essential but also potentially toxic element, both overexposure and underexposure to selenium (Se) can significantly affect public health. Rice is a common source of Se, especially in Asia. Not all Se may be released from the rice and become available for absorption into the bloodstream upon digestion in the gastrointestinal tract. Therefore, the bioaccessibility of Se in cooked white (polished) rice was assessed in vitro using the static gastrointestinal simulator SHIME (Simulator of the Human Intestinal Microbial Ecosystem).
The common cooking procedure in China prior to consumption [i.e. boiling at low rice:water ratios (1:3) until all of the water is absorbed into the rice] did not change total Se levels in the rice. Gastrointestinal digestion of the cooked rice matrix revealed a Se bioaccessibility of 67-76% of total Se. Subsequent microbial activity in the colon reduced the accessibility of Se in the cooked rice to 51-62%.
Not all Se present in cooked white rice should be considered as being bioavailable in the small intestine. A minor part is transferred with the remaining food matrix to the colon, where it is available for the microbial metabolism. © 2017 Society of Chemical Industry.
作为一种必需但也具有潜在毒性的元素，硒（Se）摄入过量或不足都会对公众健康产生重大影响。大米是硒的常见来源，尤其是在亚洲。并非所有的硒都会从大米中释放出来，并在胃肠道消化后被吸收进入血液。因此，使用静态胃肠道模拟器SHIME（人体肠道微生物生态系统模拟器）在体外评估了熟白米（糙米）中硒的生物可及性。
在中国，食用前的常见烹饪方法[即在低米水比（1:3）下煮沸，直到所有水分被大米吸收]不会改变大米中的总硒含量。对煮熟的大米基质进行胃肠道消化后发现，硒的生物可及性占总硒的67-76%。随后结肠中的微生物活动将煮熟大米中硒的可及性降低至51-62%。
并非所有存在于熟白米中的硒都应被视为在小肠中具有生物可利用性。一小部分会随着剩余的食物基质转移到结肠，在那里它可供微生物代谢利用。©2017化学工业协会。
