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.

From the fruits of Gardenia jasminoides several carotenoids were isolated and identified. Crocetin (1) was characterized by UV/vis, cochromatography, and LC-MS. The following glycosyl esters of crocetin (1) were identified:  crocin (crocetin di(β-gentiobiosyl) ester) (6) by UV/vis, 1H- and 13C-NMR, and FAB-MS and crocetin mono(β-gentiobiosyl) ester (4) by UV/vis, 1H-NMR, and LC-MS. There are strong indications for the presence of 13Z-crocin (9) (UV/vis, 1H-NMR, and LC-MS). From saffron (Crocus sativus L.), another glycosyl ester of crocetin (1) was isolated. It was identified as crocetin (β-gentiobiosyl) (β-neapolitanosyl) ester (7) by UV/vis, 1H-NMR, and MS. Keywords: Carotenoids; glycosyl esters; isolation; structure elucidation; Gardenia jasminoides; saffron; Crocus sativus

Sixteen carotenoids were isolated from the flesh of Brazilian red guavas (Psidium guajava L.). Their structures were established by means of UV-visible, 400 and 500 MHz (1)H NMR, 120 and 125 MHz (13)C NMR, mass, and circular dichroism spectra. The carotenoids were identified as phytofluene, (all-E)-, (9Z)-, (13Z)-, and (15Z)-beta-carotene, (all-E)-gamma-carotene, (all-E)-, (9Z)-, (13Z)-, and (15Z)-lycopene, (all-E,3R)-beta-cryptoxanthin, (all-E, 3R)-rubixanthin, (all-E,3S,5R,8S)-cryptoflavin, (all-E,3R,3'R, 6'R)-lutein, (all-E,3S,5R,6R,3'S,5'R,8'R)-, and (all-E,3S,5R,6R,3'S, 5'R,8'S)-neochrome. Thirteen of the carotenoids identified are reported as guava carotenoids for the first time.

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Two oxidative metabolites of lycopene in tomato paste, tomato juice, and human serum have been prepared by partial synthesis from oxidation of lycopene with m-chloroperbenzoic acid (MCPBA) followed by acidic hydrolysis. Extensive 1H and 13C NMR spectroscopy studies of the purified products of these reactions have confirmed that the major oxidation products of lycopene (I) are lycopene 1,2-epoxide (II) and lycopene 5,6-epoxide (III) (tentative assignment). Several diepoxides of lycopene, namely, lycopene 1,2;5,6-diepoxide (IV), lycopene 1,2;5‘,6‘-diepoxide (V), lycopene 5,6;5‘,6‘-diepoxide (VI), and lycopene 1,2;1‘,2‘-diepoxide (VII), which were formed as minor products, were tentatively identified. Whereas lycopene 1,2-epoxide was found to be fairly stable, lycopene 5,6-epoxide underwent cyclization to form a mixture of diastereomeric epoxides A (VIII, major) and B (IX, minor). The trivial names of 2,6-cyclolycopene-1,5-epoxides A (VIII) and B (IX) have been assigned to these compounds with a novel five-membered ring end-group. Hydrolysis of VIII and IX in dilute solutions of sulfuric acid gave an epimeric mixture of 2,6-cyclolycopene-1,5-diols A (X, major) and B (XI, minor). During chromatographic purification on n-silica gel, II and III partially cyclized to 1,16-didehydro-2,6-cyclolycopen-5-ol (XII) and epoxides VIII and IX partially converted to their respective diols, X and XI. In the course of isolation and purification, the oxidation products of lycopene with MCPBA were found to be extremely sensitive to chromatography on n-silica gel and underwent rearrangement to a number of cyclic epoxides and diols. Upon acid treatment of the mixture of lycopene epoxides, a bicyclic diepoxide of lycopene was formed, which was identified as lycopene 1,6;2,5-diepoxide (XIII). Diols X and XI have also been detected at low concentrations in tomato paste, tomato juice, and human serum. All synthetic compounds have been fully characterized by NMR, UV−vis, and MS. Keywords: 1,16-Didehydro-2,6-cyclolycopen-5-ol; 2,6-cyclolycopene-1,5-diol; 2,6-cyclolycopene-1,5-epoxide; lycopene 1,6;2,5-diepoxide; lycopene 5,6-epoxide; lycopene oxidation products; new serum carotenoids; carotenoid metabolites; NMR; HPLC/mass spectrometry

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