Nitrogenous Excretory Products of Trichinella spiralis Larvae

Abstract

The literature contains little information on the catabolic processes of nitrogen metabolism of nematode larvae. Studies on the adults of various species indicate that the principal product is ammonia, which amounts to 30 to 50% of the soluble excreted nitrogen in most cases (Weinland, 1904; Rogers, 1952; Savel, 1954). The remainder of the soluble nitrogen is accounted for as polypeptides, proteins, amino acids, small amounts of amines (Weinland, 1904; Flury, 1912; Rogers, 1952, 1955), and also as urea and/or uric acid in some species (Chitwood, 1938; Rogers, 1952; Savel, 1954). The present report concerns a quantitative evaluation of the soluble nitrogenous materials excreted by Trichinella spiralis larvae incubated aerobically in saline under axenic conditions, supplementing previous observations on the carbohydrate and lipid metabolism of this organism (von Brand, Weinstein, Mehlman, and Weinbach, 1952). The advantages of working with bacteria-free larvae were twofold. It was possible to obtain sterile incubates without the use of chemical sterilizing agents or the addition of antibiotics. The latter was important because it obviated the difficulties of separating the nitrogen-containing antibiotics from the excretory products. There was also no possibility of contamination by bacterial metabolites.