IDENTIFICATION OF LUTEIN IN CRUDE PALM OIL AND EVALUATION OF CAROTENOIDS AT VARIOUS RIPENING STAGES OF THE OIL PALM FRUIT

摘要

The xanthophylls in crude palm oil (CPO) were identified as lutein, α-carotene 5,6-epoxide, α-carotene 5,8-epoxide, and β-carotene 5,6-epoxide and/or β-carotene 5',6'-epoxide based on their electronic absorption maxima from HPLC-PDA. Lutein, a dihydroxy carotenoid, was isolated from CPO extract and its structure confirmed by co-elution with an authentic standard using HPLC-photodiode array (PDA) and mass spectra. At 7 DAA (days after anthesis), lutein was predominant with only trace amounts of α- and β-carotenes. At 21, 84 and 126 DAA, the levels of α- and β-carotenes increased although lutein still predominated. However, when the palm fruit ripens at 140 DAA, the level of lutein decreased dramatically to a minor carotene while α- and β-carotenes predominated with other minor carotenes, i.e. phytoene, lycopene, β-zeacarot.ene, γ-carotene, ζ-carotene, formed.