IDENTIFICATION, QUANTIFICATION, AND RELATIVE CONCENTRATIONS OF CAROTENOIDS AND THEIR METABOLITES IN HUMAN-MILK AND SERUM

Thirty-four carotenoids, including 13 geometrical isomers and eight me tabolites, in breast milk and serum of three lactating mothers have be en separated, identified, quantified, and compared by high-performance liquid chromatography (HPLC)-photodiode array (PDA) detection-mass sp ectrometry(MS). Among the metabolites were two oxidation products of l ycopene and four of lutein/zeaxanthin. In addition, two metabolites of lutein, formed as a result of dehydration of this dihydroxycarotenoid under acidic conditions similar to those of the stomach, have also be en identified in plasma and breast milk, The oxidative metabolites of lycopene with a novel five-membered-ring end group have been identifie d as epimeric 2,6-cyclolycopene-1,5-diols by comparison of their HPLC- UV/visible-MS profiles with those of fully characterized (H-1- and C-1 3-NMR spectroscopy) synthetic compounds. The HPLC procedures employed also detected vitamin A, two forms of vitamin E (gamma- and alpha-toco pherol), and two non-carotenoid food components, i.e., piperine and ca ffeine, in serum and breast milk.