Maintenance of Nitrogen Balance in a Young Woman by Substitution of α-Ketoisovaleric Acid for Valine

Abstract

Negative nitrogen balance was induced in a young female by removing valine from a diet containing 10.3 g of nitrogen composed of glycine, diammonium citrate and the eight essential L-amino acids in the proportion present in egg protein. Addition of α-ketoisovaleric acid decreased negative nitrogen balance and reverted it to equilibrium when an amount equivalent to three times that of valine was administered. Negative nitrogen balance returned when α-keto acid supplement was withdrawn.