Isolation of factors in linseed oil meal protective against chronic selenosis in rats.

Two new cyanogenic glycosides, linustatin and neolinustatin, were isolated from linseed oil meal. Each of the compounds was fed to rats in a corn-based diet at levels of 0.1 and 0.2%. At the 0.2% level, both substances gave significant protection against growth depression caused by 9 ppm selenium as sodium selenite. Both compounds also promoted a significant increase in liver and kidney weight over the selenium control animals. Linustatin and neolinustatin are closely related in structure to linamarin and lotaustralin and were found to be present in linseed oil meal at levels of 0.17 and 0.19%, respectively. Linamarin fed at the level of 0.2% also gave significant protection against growth depression and liver damage. A related cyanogenic glycoside, amygdalin, appeared to give a small but nonsignificant protective response. The isolation of the two new glycosides provides a probable explanation for the protective activity of linseed oil meal against selenium toxicity.