The chemical forms of Se include organic and inorganic Se. The organic Se compounds include Se-containing polysaccharides, Se-containing proteins etc., and the inorganic Se compounds include selenonic acid and the selenite salt. 硒化合物的存在形式包括有机硒和无机硒两种,有机硒主要包括硒多糖、硒蛋白等,无机硒主要包括硒酸和亚硒酸。