A rapid profiling of hypolipidemic agents in dietary supplements by direct injection tandem mass spectrometry

A new, fast-screening method for identification of various pharmacologically active ingredients in cholesterol-lowering dietary supplements using direct injection mass spectrometry was developed. The optimized method was proven to be useful for multitarget screening: 17 compounds of interest were identified, including monacolin K and its acid form, cynarin, green tea catechines, genistein, daidzein, guggulsterones, allicin and l-arginine. The method was successfully applied for the fingerprint analysis of dietary supplements containing only one or several cholesterol-lowering agents including lovastatin registered as a drug. According to the obtained results, it is apparent that cholesterol-lowering dietary supplements are poorly standardized, as two samples did not contain active ingredients (monacolin K, monacolin K acid form and cynarin). Moreover, the application of the proposed direct injection method to quality control of cholesterol-lowering dietary supplements may be proposed for the routine analysis of a large number of samples in the laboratories of regulatory agencies.