文章基本信息

标题：Structural analyses of polymorphic transitions of sn -1,3-distearoyl-2-oleoylglycerol (SOS) and sn -1,3-dioleoyl-2-stearoylglycerol (OSO): assessment on steric hindrance of unsaturated and saturated acyl chain interactions
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作者：Junko Yano ; Kiyotaka Sato ; Fumitoshi Kaneko 等
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：1999
卷号：40
期号：1
页码：140-151
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：Polymorphic transformations in two saturated-unsaturated mixed acid triacylglycerols, SOS ( sn -1,3-distearoyl-2-oleoylglycerol) and OSO ( sn -1,3-dioleoyl-2-stearoylglycerol), have been studied by FT-IR spectroscopy using deuterated specimens in which stearoyl chains are fully deuterated. A reversible phase transition between sub α and α and a series of irreversible transitions (α→γ→β′→β (β₂, β₁) for SOS and α→β′→β for OSO) were studied with an emphasis on the conformational ordering process of stearoyl and oleoyl chains. The α→ sub α reversible transition was due to the orientational change of stearoyl chains in the lateral directions from the hexagonal subcell to a perpendicularly packed one. As the first stage of the series of irreversible transitions from α to β, the conformational ordering of saturated chains took place in the α→γ transition of SOS and in the α→β′ transition of OSO; one stearoyl chain in SOS and OSO takes the all- trans conformation and the second stearoyl chain in SOS takes the bent conformation like those observed in the most stable β-type. As the final stage, the ordering of unsaturated chains occurred in the β′→β transition both for SOS and OSO. A conversion in the layered structure from bilayer to trilayer was also accompanied by the conformational ordering in the α→γ transition of SOS and in the β′→β transition of OSO. —Yano, J., K. Sato, F. Kaneko, D. M. Small, and D. R. Kodali. Structural analyses of polymorphic transitions of sn -1,3-distearoyl-2-oleoylglycerol (SOS) and sn -1,3-dioleoyl-2-stearoylglycerol (OSO): assessment on steric hindrance of unsaturated and saturated acyl chain interactions. J. Lipid Res. 1999. 40: 140–151.
关键词：polymorphism ; phase behavior ; infrared spectroscopy ; molecular packing ; molecular conformation ; deuteration