Analysis of the sulfomycin component of alexomycin in animal feed by enhanced solvent extraction and supercritical fluid chromatography

Enhanced solvent extraction (ESE) was used to isolate components of alexomy cin from different types of animal feed samples. It was demonstrated that E SE was more economical as regards money and, for this particular matrix, tw ice as fast as supercritical fluid extraction (SFE) even though it was demo nstrated that alexomycin can be extracted from feed quantitatively using bo th ESE and SFE. Supercritical fluid chromatography was used to separate ale xomycin from other co-extractives of feed since liquid chromatography was u nable to isolate the alexomycin for quantification purposes. Our results al so showed that the concentration of alexomycin in an extruded sample was ap proximately half of the concentration which was originally added to the fee d. (C) 2000 Elsevier Science B.V. All rights reserved.