Identification, quantification, and relative concentrations of carotenoids and their metabolites in human milk and serum.
Thirty-four carotenoids, including 13 geometrical isomers and eight metabolites, in breast milk and serum of three lactating mothers have been separated, identified, quantified, and compared by high-performance liquid chromatography (HPLC)-photodiode array (PDA) detection-mass spectrometry (MS). Among the metabolites were two oxidation products of lycopene 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 been identified in plasma and breast milk. The oxidative metabolites of lycopene with a novel five-membered-ring end group have been identified as epimeric 2,6-cyclolycopene-1,5-diols by comparison of their HPLC-UV/visible-MS profiles with those of fully characterized (1H- and 13C-NMR spectroscopy) synthetic compounds. The HPLC procedures employed also detected vitamin A, two forms of vitamin E (gamma- and alpha-tocopherol), and two non-carotenoid food components, i.e., piperine and caffeine, in serum and breast milk.
Khachik
F
F
Carotenoid Research Unit, Beltsville Human Nutrition Research Center, U.S. Department of Agriculture, ARS, Beltsville, Maryland 20705, USA.
Spangler
C J
CJ
Smith
J C
JC
Canfield
L M
LM
Steck
A
A
Pfander
H
H
D000328:Adult; D002338:Carotenoids / Q000032:analysis* / Q000097:blood*; D005260:Female; D006801:Humans; D007774:Lactation; D008895:Milk, Human / Q000737:chemistry*
D002338:Carotenoids