title: Thermotropic phase behaviour of lipid bilayers containing carotenoid pigment canthaxanthin: a differential scanning calorimetry study.
abstract: In this study we address the problem of the effect of canthaxanthin on the thermotropic properties of lipid membranes formed with lipids which differ in the thickness of their hydrophobic core, size of polar heads or presence of the ester carbonyl group. For all the lipids a decrease in main transition enthalpy has been observed, indicating that canthaxanthin alters the membrane properties in its gel phase. The strongest influence of canthaxanthin on main phase transition and pretransition has been observed for the lipid having the thinnest hydrophobic region. Component analysis indicates a distinct cooperativity change, which most probably colligates with the formation of new thermotropic phases. The effect of canthaxanthin has been almost negligible in the case of phosphatidylethanolamines. The absence of the ester carbonyl group results in different thermotropic behavior, especially for low canthaxanthin concentrations. The effect of canthaxanthin is explained in terms of its organization within the membrane.
authors.affiliation: Department of Physics, Agricultural University, 20-033 Lublin, Poland. sujak@ar.lublin.pl
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Sujak
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Strzałka
authors.forename: Wiesław I
authors.initials: WI
authors.lastname: Gruszecki
mesh_terms: D002152:Calorimetry, Differential Scanning; D016644:Canthaxanthin / Q000737:chemistry*; D002338:Carotenoids / Q000737:chemistry; D005782:Gels; D006358:Hot Temperature; D057927:Hydrophobic and Hydrophilic Interactions; D008051:Lipid Bilayers / Q000737:chemistry*; D008563:Membrane Lipids / Q000737:chemistry; D044367:Phase Transition; D013696:Temperature
chemical_list: D005782:Gels; D008051:Lipid Bilayers; D008563:Membrane Lipids; D002338:Carotenoids; D016644:Canthaxanthin