Analysis of Lycopene Stereoisomers in Tomato Extracts and Human Serum

3 ANALYSIS OF LYCOPENE STEREOISOMERS IN TOMATO EXTRACTS AND HUMAN SERUM 

Vegetables are the most important source of carotenoids for humans. Most vegetables contain a variety of carotenoids [30,31]. Only carrots O-carotene) and tomatoes (lycopene) [32] contain one major carotenoid. However, even in these vegetables, several minor components can be identified, most of them geometrical isomers - structurally similar, but nevertheless totally different. For nutritional aspects, the level of these stereoisomers in nature is significant, because their biomedical properties can differ enormously. 

As shown, tomatoes contain solely carotenes - lycopene (95 % of the total carotenoid content) and (3-carotene (5 %). The good resolution and shape of the separation is due to the enhanced shape selectivity of C30 stationary phases in comparison to Cis phases [33,34], Furthermore, C30 phases have a higher loading capacity, and therefore are preferably suitable for LC-NMR experiments [35-37]. 

Peak Retention time (min) Peak area (%) Identification 

The human body stores a variety of carotenes (lycopene, a- and (3-carotenes), as well as xanthophylls (lutein, zeaxanthin and cryptoxanthin) [38]. Besides the main naturally occurring all-E configuration, there also exist some Z-stereoi-somers of (3-carotene and lycopene in the human serum at remarkable levels, as shown in Table 5.2.2 [39,40]. 

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