STRUCTURAL INVESTIGATIONS OF BETA' TRIACYLGLYCEROLS - AN X-RAY-DIFFRACTION AND MICROSCOPIC STUDY OF TWINNED BETA' CRYSTALS

被引:22
作者
BIRKER, PJMWL [1 ]
DEJONG, S [1 ]
ROIJERS, EC [1 ]
VANSOEST, TC [1 ]
机构
[1] UNILEVER RES LABS VLAARDINGEN,3133 AT VLAARDINGEN,NETHERLANDS
关键词
BETA'; CRYSTAL STRUCTURE; ELECTRON MICROSCOPY; FAT; POLYMORPHISM; TRIACYLGLYCEROL; TWINNING; X-RAY DIFFRACTION;
D O I
10.1007/BF02657533
中图分类号
O69 [应用化学];
学科分类号
081704 ;
摘要
To reveal the structure of beta' triacylglycerols in detail, LML (C12C14C12) was purified by a zone-melting procedure, and twinned crystals of beta' stable LML were obtained from a melt. beta' LML crystallizes in the monoclinic space group C2, with eight molecules in the unit cell. A powder X-ray diffraction study of solid compounds of 1:1 mixtures of selected triacylglycerols led to the conclusion that the triacylglycerol molecules in the beta' modification have a 1,2 chair-conformation (i.e., the fatty acid chains on glycerol positions 1 and 2 are adjacent, with the chain on the 3-position forming the back rest of the chair). Packing studies and the positions of two-fold axes and two-fold screw axes in the unit cell require that the molecules are bent at the glycerol site. The fatty acid chains make an angle of 25-degrees with the long axis of the unit cell. Electron micrographs and precession photographs indicate that the twinning results from the stacking of a large number of thin crystalline platelets in two distinct orientations.
引用
收藏
页码:895 / 906
页数:12
相关论文
共 21 条
[1]  
Abrahamsson S, 1978, Prog Chem Fats Other Lipids, V16, P125, DOI 10.1016/0079-6832(78)90039-3
[2]   HABIT OF TRIGLYCERIDE CRYSTALS [J].
ALBON, N ;
PACKER, A .
NATURE, 1965, 207 (5001) :1088-&
[3]   POLYMORPHISM OF GLYCERIDES [J].
CHAPMAN, D .
CHEMICAL REVIEWS, 1962, 62 (05) :433-&
[4]  
DeJong S., 1978, ACTA CRYST, VB34, P1570, DOI [10.1107/S0567740878006093, DOI 10.1107/S0567740878006093]
[5]   CRYSTAL STRUCTURE OF A DIACID TRIGLYCERIDE [J].
DOYNE, TH ;
GORDON, JT .
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY, 1968, 45 (05) :333-&
[6]  
Hagemann JW, 1988, CRYSTALLIZATION POLY
[7]   ON THE CRYSTAL-STRUCTURE OF THE BETA'-FORM OF TRIGLYCERIDES AND STRUCTURAL-CHANGES AT THE PHASE-TRANSITIONS LIQ.-]ALPHA-]BETA'-]BETA [J].
HERNQVIST, L ;
LARSSON, K .
FETTE SEIFEN ANSTRICHMITTEL, 1982, 84 (09) :349-354
[8]   ON THE CRYSTAL-STRUCTURE OF THE BETA'-1-FORM OF TRIGLYCERIDES AND THE MECHANISM BEHIND THE BETA'-1-]BETA-TRANSITION OF FATS [J].
HERNQVIST, L .
FETT WISSENSCHAFT TECHNOLOGIE-FAT SCIENCE TECHNOLOGY, 1988, 90 (11) :451-454
[9]   REFINEMENT OF STRUCTURE OF BETA-TRICAPRIN [J].
JENSEN, LH ;
MABIS, AJ .
ACTA CRYSTALLOGRAPHICA, 1966, 21 :770-&
[10]   TIME RESOLVED X-RAY-DIFFRACTION STUDIES OF THE POLYMORPHIC BEHAVIOR OF TRIPALMITIN USING SYNCHROTRON RADIATION [J].
KELLENS, M ;
MEEUSSEN, W ;
RIEKEL, C ;
REYNAERS, H .
CHEMISTRY AND PHYSICS OF LIPIDS, 1990, 52 (02) :79-98