Über die optische Aktivität der durch biochemische Synthese entstandenen Acetoine

Abstract

Optically active acetoin was prepared by treating pea, soybean, lupine and lucerne meals, and animal tissues with Na-pyruvate and acetaldehyde. Protein was removed by trichloracetic acid, and the pH of the filtrate adjusted to 4.5 by the addition of Na2HPO4.12 H2O. The acetoin soln. was conc. by repeated distillation at 100[degree] under atmospheric pressure without racemization tak-ing place. From the seed meal acetoin having an optical rotation of (a)20D- + 38[degree] was obtained. A variable mixture of acetoin was obtained from animal tissues, (a)20D for pigeon muscle and swine liver being [long dash]74[degree], and for swine muscle and swine kidney being [long dash]86[degree]. The decarboxylating mechanism of pyruvic acid was the same in yeast and animal cells, but was different in plant cells. It made no difference in activity whether the acetoin was formed from added pyruvate or aldehyde.