Schmidt Walter F, Mookherji Swati, Crawford Michael A
United States Department of Agriculture, Beltsville Agricultural Research Service, Agricultural Research Service, Beltsville, MD 20705, USA.
Chem Phys Lipids. 2009 Mar;158(1):10-5. doi: 10.1016/j.chemphyslip.2008.12.005. Epub 2008 Dec 25.
The structural basis of immiscibility of stearic acid (SA) in two unsaturated lipids at room temperature was examined. A 5% SA mixture in octadec-9-enoic acid (OA) is cloudy; a 5% SA solution in the methyl ester of OA (MeOA) is fully miscible. At 10% SA in MeOA, a clear and immiscible phase formed. The composition of this immiscible phase however was not 10% SA, but 25% SA. Adding additional SA altered the amount of the second phase, not its stoichiometry. Molecular mechanics explains the molecular basis for the ratio of saturated and unsaturated lipids in the different phases. Packing order of lipids within a unit volume explains the discrete lipid composition ratio forming each of the observed miscible and immiscible phases. The smallest unit cell volume that explains the observed stoichiometry is a cube (not a sphere).
研究了硬脂酸（SA）在室温下于两种不饱和脂质中不互溶的结构基础。在9-十八烯酸（OA）中5%的SA混合物是浑浊的；在OA的甲酯（MeOA）中5%的SA溶液是完全互溶的。在MeOA中10%的SA时，形成了一个清澈且不互溶的相。然而，这个不互溶相的组成不是10%的SA，而是25%的SA。添加额外的SA改变了第二相的量，而非其化学计量比。分子力学解释了不同相中饱和与不饱和脂质比例的分子基础。单位体积内脂质的堆积顺序解释了形成每个观察到的互溶和不互溶相的离散脂质组成比。解释观察到的化学计量比的最小晶胞体积是一个立方体（而非球体）。
Zotero 插件