长寿地区大米中硒的有机形态及其生物利用度研究

为了探究典型长寿区大米有机硒的赋存形态与人体硒营养水平的关系，本文分析了江西典型长寿区大米中有机硒、谷蛋白硒、硒代蛋氨酸（Selenomethionine, SeMet）等的组成特征，并运用胃肠体外模拟法对大米硒的生物可利用度及其与各有机硒组分之间的相关关系进行了研究。结果表明，大米中的硒主要以有机形式（78.67 ± 13.52%）赋存，其中，53.73 ± 8.27%的有机硒为谷蛋白硒，且65%以上的谷蛋白硒可酶解消化为SeMet。大米硒的生物可利用度为55.58 ± 10.53%。大米谷蛋白中SeMet比例相对较高且易于被人体吸收利用，这可能与当地居民的健康长寿关系密切。不过，SeMet与大米可利用硒的相关系数仅为0.55。因此，未来有必要对大米中不同硒蛋白的代谢产物（如SeMet）进行研究。

Organic Selenium Forms and Selenium Bioavailability in Rice Grains from a typical longevity area, Wentang Town, Yichun City, Jiangxi Province

To explore the relationship between organic selenium (Se) forms in rice and its nutrition levels in human body, this paper analyzed characteristics of the organic Se, the glutelin Se and the Selenomethionine (SeMet) in rice from a typical longevity area in Jiangxi province. An in-vitro gastrointestinal simulation method was selected to discuss the relationship between bioavailability of Se in rice and organic Se forms. The results showed that the organic Se was the dominated form (78.67 ± 13.52%), and the glutelin Se accounted for 53.73 ± 8.27% of the organic Se content, in which more than 65% could be hydrolyzed to the form of SeMet. The simulated results indicated that the bioavailability of Se in rice was 55.58 ± 10.53%. The percentage of SeMet in the rice glutelin was relatively high and SeMet was easily absorbed by the human body, which has a close relationship to the local resident longevity. Nevertheless, the correlation coefficient between the available Se and the SeMet was only 0.55. Thus, it is necessary to investigate the Se-containing-proteins metabolites, such as SeMet in future.