High-performance liquid chromatography for the characterization of carotenoids in the new sweet orange (Earlygold) grown in Florida, USA

High-performance liquid chromatography with photodiode array detection was developed for the separation and identification of carotenoids from a new sweet orange, Earlygold, Carotenoid pigments were extracted using hexane-actone-ethanol and saponified using 10% methanolic potassium hydroxide. More than 25 carotenoid pigments were separated within 40 min using a ternary gradient (acetonitrile-methanol, methyl tert-butyl ether and water) elution on a C-30 reversed-phase column, The carotenoid pattern of Earlygold was generally similar to the early season Hamlin but with some quantitative differences, especially with violaxanthin. Major carotenoids including violaxanthin, lutein, beta -cryptoxanthin, antheraxanthin. luteoxanthin, zeaxanthin, beta -carotene, and alpha -carotene were identified based on on-line spectral data obtained by a photodiode array detector, and comparison to the spectra of the standards and reported values. A numerical notation, the ratio of the peak heights between absorption bands, was also calculated to compare to the literature values. (C) 2001 Elsevier Science BN. All rights reserved.