共轭亚油酸及其生物学功能研究进展

共轭亚油酸（CLA）是含有共轭双键的亚油酸家族的总称,在这个家族中至少有28个同分异构体,它们主要存在于反刍动物的脂肪中.其中含量最多,生物学功能最为广泛的c9t11 CLA,占整个CLA总量的80％～90％.其生物学功能包括抗肿瘤细胞生长、改善心血管系统功能、增强机体免疫力以及预防糖尿病等.其次为t1oc12 CLA,占CLA总量的3％～5％,其主要生物学功能为降低脂肪酸的合成,抑制脂肪细胞的分化与生长等.给反刍动物饲喂具有不同脂肪酸含量特征的油菜籽、长链不饱和脂肪酸等,或对体内硬酯酰辅酶A去饱和酶的活性进行调节,均可提高反刍动物组织中的CLA含量,从而生产出具有促进人体健康的功能性畜产品.未来的研究应该阐明共轭亚油酸中的共轭结构是如何发挥其生物学功能的,在其他营养物质中是否也存在具有生物学功能的结构形式.

Research Development on Conjugated Linoleic Acids and Their Biological Functions

Conjugated linoleic acid （CLA） is a family of linoleic acids with conjugated double bonds.There are at least 28 isomers in this family,which are mainly found in ruminant fats.The isomer with the most biological functions and the most abundance in the tissue is the c9t11 CLA,accounting for 80％～90％ of the total CLA.Its biological functions include anti-tumor cell growth,improving cardiovascular system function,enhancing immunity and preventing diabetes et al.The second abundant isomer is t10c12 CLA,accounting for about 3％～5％ of the total CLA,and its main biological function is to reduce the synthesis of fatty acids and to inhibit the differentiation and growth of fat cells and so on.Feeding ruminant oilseeds,polyunsaturated long chain fatty acids,or regulating the activity of stearic coenzyme A desaturase increase CLA content in ruminant tissues,thereby producing health-promoting and functional animal products.Future studies should clarify how the conjugated structure in linoleic acids exerts their biological functions,and investigate whether there are similar structures with biological functions in other nutrients.