Abstract: The electronic absorption spectral shifts of all-E-β,β-carotene and ψ,ψ-carotene in supercritical carbon dioxide were studied. Experimental results indicated that hypsochromic spectral shifts of all-E-β,β-carotence and ψ,ψ-carotene in CO2 phase are observed in comparison of those in hexane. Additionally,bathochromic spectral shifts of the tested carotenes are observed while pressure and temperature variations-induced increase in the density of CO2 takes place. Both of the spectral shifts are considered fundamentally to be related with polarizability term (further referred to the refractive index) variation of CO2 according to the established spectral theory of carotenoids in organic solvents.

Key words: &beta, -carotene； lycopene； electronic absorption spectrum； supercritical fluid；