Volatile fatty acids from axenic Ascaris lumbricoides

Abstract

1. 1. The investigations in this study have been concerned with the separation and identification by gas-liquid chromatography of the methyl esters of volatile fatty acids excreted from axenic Ascaris lumbricoides. 2. 2. Ten methyl ester peaks, of which three were major components and seven minor components, were detected. All but one were tentatively identified by comparison with the relative retention times of comparable standards under the same conditions. 3. 3. The three major components were positively identified by infrared spectroscopy and preparation of amide derivatives as α-methyl n-butyric, n-valeric, and isocaproic acids. The minor components were acetic, propionic, isobutyric and/or trimethylacetic, n-butyric, trans-α-niethyl crotonic (tiglic), and n-caproic acids, plus an unknown branched C 7 or C 8 acid. 4. 4. The total mole percentages of the methyl esters of different carbon numbers were: C 2, 0.27%; C 3, 0.77%; C 4, 1.14%; C 5, 38.0%; C 6, 56.2%; and C 7–8 3.56%. The most abundant individual acids found were isocaproic, 55.1 mole %, and α-methyl- n-butryic, 31.8 mole %.