Tocopherol content of skeletal muscle; comparison of chemical and bioassay methods.

The number of determinations of tocopherols in muscle tissue reported in the literature is small. This may be due to the complexity and timeconsuming technique of both the chemical and biological methods, as well as to the poor agreement between the two assays. An accurate account of the chemical assay of vitamin E has recently been compiled in Dr. K. C. D. Hickman’s 1aboratory.l The fact that the chemical determinations usually yielded smaller values than the bioassays was probably due to hydrolysis of the extracts to eliminate fats and filtration through an adsorbent earth to separate the tocopherols from carotenes. These procedures were found to be unnecessary if the method of I&units and Beaver (1, 2) for the determination of tocopherols in the presence of fats was applied to muscle extracts.