Angle resolved depolarised resonance Raman studies of beta-carotene in lipid/water mixtures

The orientational ordering of beta-carotene incorporated in lamellar model membranes above their main phase transitions has been studied by angle resolved depolarised Resonance Raman scattering. The ordering strongly depends on the chemical composition of the lipid bilayers: in di-oleoyl lecithin (DOPC) the carotenoid molecules lie parallel to the bilayer plane, while in di-galactosyl diglyceride ( DGDG ) a bimodal distribution was found with molecules lying both parallel and perpendicular to the membrane phase.