Grandgirard A, Piconneaux A, Sebedio J L, O'Keefe S F, Semon E, Le Quére J L
Station de Recherches sur la Qualite des Aliments de l'Homme, Dijon, France.
Lipids. 1989 Sep;24(9):799-804. doi: 10.1007/BF02544587.
Mono trans geometrical isomers of 20:5 n-3 and 22:6 n-3 were detected in liver lipids of rats fed heated linseed oil. The isomers were identified as being 20:5 delta 5c,8c,11c,14c,17t and 22:6 delta 4c,7c,10c,13c,16c,19t. These fatty acids were isolated as methyl esters by preparative high-performance liquid chromatography (HPLC) on reversed phase columns followed by silver nitrate thin layer chromatography (AgNO3-TLC). The structures were identified using partial hydrazine reduction, AgNO3-TLC of the resulting monoenes, oxidative ozonolysis of each monoene band, and gas-liquid chromatography (GLC) of the resulting dimethyl esters and monomethyl esters. Fourier-transform-infrared spectrometry confirmed the trans geometry in isolated 20:5 and 22:6 isomers. The isomers of eicosapentaenoic and docosahexaenoic acids in liver lipids probably resulted from desaturation and elongation of 18:3 delta 9c,12c,15t, a geometrical isomer of linolenic acid present in the heated dietary oil.
在喂食加热亚麻籽油的大鼠肝脏脂质中检测到了20:5 n-3和22:6 n-3的单反式几何异构体。这些异构体被鉴定为20:5 δ5c,8c,11c,14c,17t和22:6 δ4c,7c,10c,13c,16c,19t。通过反相柱制备高效液相色谱（HPLC），随后进行硝酸银薄层色谱（AgNO3-TLC），将这些脂肪酸分离为甲酯。使用部分肼还原、所得单烯的AgNO3-TLC、每个单烯带的氧化臭氧分解以及所得二甲酯和单甲酯的气液色谱（GLC）来鉴定结构。傅里叶变换红外光谱证实了分离出的20:5和22:6异构体中的反式几何结构。肝脏脂质中二十碳五烯酸和二十二碳六烯酸的异构体可能是由加热食用油中存在的亚麻酸几何异构体18:3 δ9c,12c,15t的去饱和和延长作用产生的。
