Distribution of Selenium in Bovine Milk and Selenium Deficiency in Rats Fed Casein-based Diets, Monitored by Lipid Peroxide Level and Glutathione Peroxidase Activity
Year: 1981
Type: article
Abstract: A major proportion of selenium in bovine milk was found in fluorornetric analysis to be associated with the casein fraction, largely in alkali-labile form, and the rest with the whey fraction mostly in free selenite form.This uneven distribution of milk selenium seems to provide an explanation for selenium deficiency in purified caseins.The activity of glutathione peroxidase, a selenoprotein, in the liver of growing male rats fed ad libitum low-selenium diets containing either vitamin-free casein or Torula yeast 0.065 ±0.012 or 0.015 ±0.004fig Se/g diet, respectively) for 3 weeks decreased to 4 to 6% of that of the control rats fed a commercial stock diet (0.185±0.092figSe/g diet).Selenium status was evaluated by three different parameters for the rats assigned under pair-feeding regimen to those vitamin-free casein-based diets which were supplemented with graded levels of selenium as sodiumselenite.Thehepatic levels of the thiobarbituric acid-reactive substance, an indication of lipid peroxidation, decreased to control level with selenium supplementation per g diet of 0. 1 fig and over.The hepatic glutathione peroxidase activity reached a plateau above a 0. 1 figjg diet of selenium supplementation, whereas the erythrocyte enzyme activity increased with increasing levels of supplementary selenium.These results support the notion that semi-purified diets containing vitamin-free casein as a prime protein source would not satisfy the selenium requirement of growing animals unless deliberately supplemented with additional selenium.
Authors: Munehiro Yoshida, Kyoden Yasumoto, Kimikazu Iwami, Hiroyuki Tashiro
Institution: Kyoto University
Language: English
Subfield: Nutrition and Dietetics
Field: Nursing
Domain: Health Sciences
SDG: Zero hunger
Open Access status: bronze
OpenAlex ID: W2010632387