Abstract: Carotenoid oxidation products have various structures, among which epoxides and
apo- or seco-carotenoids are the two main families. Although both these compound types are
widely found in the natural world, the sensitivity of carotenoids to oxidation means they can
also be an unwanted presence in in vitro assays. On the other hand, carotenoid oxidation
products have also provided chemists with useful chemical tools for the structural identification of carotenoids, and in the natural world they are important biological mediators for
plants and animals. In vitro, carotenoid oxidation products have been found to exert various
effects which are either potentially beneficial or, on the contrary, detrimental to human
health. However, to date, few carotenoid oxidation products have been found in humans.
In order to isolate and characterize carotenoid oxidation products and identify their
mechanism of formation, we set up two chemical oxidation systems. Lycopene was oxidized
with potassium permanganate in a biphasic system to produce the fullest possible range of
apo-lycopenals and some diapocarotene-dials. Biomimetic chemical systems of a heminic
enzyme center were shown to oxidize lycopene and β-carotene into different families of molecules. Analysis by high-performance liquid chromatography coupled with a diode arrayUV/vis detector and a mass spectrometry detector (HPLC–DAD–MS) was used to gain insight into the possible mechanisms of formation of the carotenoid oxidation products formed
by these biomimetic systems