Rao Reena, Lokesh Belur R
Department of Lipid Science and Traditional Foods, Central Food Technological Research Institute, Mysore-570 013, India.
Lipids. 2003 Sep;38(9):913-8. doi: 10.1007/s11745-003-1144-3.
Lipase-catalyzed interesterification was used to prepare structured TG from coconut oil TG by partially replacing some of the atherogenic saturated FA with stearic acid, which is known to have a neutral effect on lipid levels in the body. The level of stearic acid was increased from 4% in the native coconut oil to 40% in the structured lipids, with most of the stearic acid being incorporated into the sn-1 and sn-3 positions of TG. When structured lipids were fed to rats at a 10% level for a period of 60 d, a 15% decrease in total cholesterol and a 23% decrease in LDL cholesterol levels in the serum were observed when compared to those fed coconut oil. Similarly, the total and free cholesterol levels in the livers of the rats fed structured lipids were lowered by 31 and 36%, respectively, when compared to those fed coconut oil. The TG levels in the serum and in the liver showed decreases of 14 and 30%, respectively, in animals fed structured lipids. Rats fed cocoa butter and structured lipids having a similar amount of stearic acid had similar lipid levels in the serum and liver. These studies indicated that the atherogenic potential of coconut oil lipids can be reduced significantly by enriching them with stearic acid. This also changed the physical properties of coconut oil closer to those of cocoa butter as determined by DSC.
脂肪酶催化的酯交换反应被用于从椰子油甘油三酯制备结构化甘油三酯,通过用硬脂酸部分替代一些致动脉粥样硬化的饱和脂肪酸,已知硬脂酸对体内脂质水平具有中性作用。硬脂酸的含量从天然椰子油中的4%增加到结构化脂质中的40%,大部分硬脂酸被并入甘油三酯的sn-1和sn-3位。当以10%的水平给大鼠喂食结构化脂质60天时,与喂食椰子油的大鼠相比,血清中总胆固醇降低了15%,低密度脂蛋白胆固醇水平降低了23%。同样,与喂食椰子油的大鼠相比,喂食结构化脂质的大鼠肝脏中的总胆固醇和游离胆固醇水平分别降低了31%和36%。喂食结构化脂质的动物血清和肝脏中的甘油三酯水平分别降低了14%和30%。喂食可可脂和具有相似硬脂酸含量的结构化脂质的大鼠在血清和肝脏中的脂质水平相似。这些研究表明,通过用硬脂酸富集椰子油脂质,可以显著降低其致动脉粥样硬化的潜力。这也使椰子油的物理性质更接近通过差示扫描量热法测定的可可脂的物理性质。