Influence du régime alimentaire sur la concentration en acides aminés non protéiques dans l'hémolymphe des larves âgées d' Agria affinis (Fall.)

Abstract

Results are presented on the non-protein amino acid content in the haemolymph of Agria affinis matured larvae reared on two different diets. The first group of larvae was fed on pork liver, the second group was reared under aseptic conditions on a chemically defined diet whose amino acid mixture was similar in composition to pork liver proteins. Most amino acids were encountered in smaller amounts in diet-fed larvae. Nevertheless, aspartic acid and α-alanine were about equal in the haemolymph of both; asparagine, methionine sulphoxide, and methylhistidine were absent, and the amount of α-amino- n-butyric acid, phenylglutamic acid, proline, and serine exceeded the amount found in liver-fed larvae. The low content of glutamic acid, glutamine, and asparagine shows either a low content or a partial inhibition of transaminases and transamidases concerned in the synthesis of these substances. The transformation of glutamic acid to proline and phenylglutamic acid is done at the expense of its amidation. High concentration of serine is due to the absence of methyl-histidine whose synthesis by transmethylation might be impaired by lack of zinc in the diet.