Effect of linamarin on thiocyanate production and thyroid activity in rats

The principal cyanogenic glucoside in cassava is linamarin (2-hydroxyisobutyronitrile-beta-D-glucoside). Addition of pure linamarin to a diet based on 10% vitamin-free casein did not affect the weight gain of rats. However, as expected, the animals that received the casein diet supplemented with methionine gained more weight than those that received the unsupplemented diet. The amount of thiocyanate ion excreted in the urine by the animals that received linamarin was higher than that excreted by the animals that did not receive linamarin at both levels of dietary methionine. The plasma thiocyanate concentration was also higher for linamarin-fed animals than for animals that did not receive linamarin. Higher plasma thiocyanate levels were associated with a lower percentage uptake of radioiodine by the thyroid.