沪浙地区不同泌乳期母乳脂肪酸组成及分布研究

Fatty Acid Composition and Distribution in Different Lactation Periods of Breast Milk from Shanghai and Zhejiang

研究了我国沪浙地区不同泌乳期(0～1,1～3,3～6和6～12月)母乳总脂肪酸、甘油三酯sn-2位脂肪酸和磷脂脂肪酸组成及分布。结果显示,随着泌乳期的延长,母乳脂肪中的中链饱和脂肪酸(MCSFA)、C_(12:0)和C_(14:0)含量逐渐升高,多不饱和脂肪酸(PUFA)、C_(18:2n-6)(LA)和C_(18:3n-3)(ALA)含量先升高后下降,C_(20:4n-6)(ARA)和C_(22:6n-3)(DHA)含量先显著下降而后趋于稳定,而饱和脂肪酸(SFA)、C_(16:0)和C_(18:0)含量几乎没有变化。母乳脂肪酸在甘油三酯结构中的位置分布具有独特性:MCSFA、SFA、C_(12:0)、C_(16:0)、ARA和DHA主要结合在sn-2位上,而MUFA、C_(18:1n-9)、PUFA、LA和ALA主要分布在sn-1,3位上,且这种独特的位置分布几乎不随泌乳期的变化而变化。母乳磷脂脂肪酸中的ARA和DHA含量尽管在不同泌乳期之间有所差异,但均显著高于其在母乳总脂肪酸中的含量。研究结果为我国婴儿配方乳粉的脂质母乳化特别是结构母乳化提供了重要的数据支撑。

Fatty acid composition and distribution in total lipids, triglyceride sn -2 position and phospholipids of breast milk from Shanghai and Zhejiang during different lactation periods (0~1, 1~3,3~6 and 6~12 months) were investigated.As the lactation period prolonged, the contents of medium-chain saturated fatty acids (MCSFA), C12:0 and C14:0 in breast milk total lipids increased gradually, polyunsaturated fatty acids (PUFA), C18:2n-6 (LA) and C18:3n-3(ALA) levels increased at first and decreased subsequently, while C20:4n-6(ARA) and C22:6n-3(DHA) percentages decreased significantly at first and then tend to be stable.No significant variations were found in the contents of saturated fatty acid (SFA),C16:0 and C18:0 in breast milk total lipids during the whole lactation period.The position distribution of fatty acids in breast milk triglyceride structure was unique:MCSFA, SFA,C12:0,C16:0,ARA and DHA were mainly located in the sn -2 position, while MUFA,C18:1n-9,PUFA, LA and ALA were predominantly esterified in the sn-1 , 3 positions.Such a unique position distribution was very stable throughout the lactation periods.Though the content of ARA and DHA in breast milk phospholipids varied between different lactation stages, they were significantly higher than those in breast milk total lipids.The results obtained in the present study were useful for the lipid simulation especially lipid structure simulation researches of infant formula.