P. Riso et M. Porrini, DETERMINATION OF CAROTENOIDS IN VEGETABLE FOODS AND PLASMA, International journal for vitamin and nutrition research, 67(1), 1997, pp. 47-54
In this paper a HPLC method for the determination of lutein, zeaxanthi
n, beta-cryptoxanthin, alpha-carotene, beta-carotene and lycopene in m
ixed vegetables and fruit and in human plasma is described. The carote
noids were well separated and the separation was achieved within fifte
en minutes using a HPLC system consisting of a 5 mu m Vydac 201TP54 C-
18 column, an UV detector; methanol-tetrahydrofuran (95:5 v/v) as mobi
le phase and a flow rate of 1.0 ml/min. The validity of the separation
method was determined by evaluating the linearity of the calibration
graphs of each carotenoid (between 0.1 and 1.0 mu g/ml for all compoun
ds except lycopene between 0.1 and 0.8 mu g/ml, r=0.999) and the accur
acy of the chromatographic response (CV <10%). The reproducibility of
the retention times was also good. In the foods samples the extraction
procedure was very effective whereas, the saponification step signifi
cantly damaged some of the carotenoids. In the plasma the extraction a
nd separation of these compounds were also effective and the qualitati
ve data obtained comparable with those reported in literature. The use
of echinenone as internal standard helped to improve quality control.