School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, China.
Molecules. 2013 Aug 13;18(8):9704-16. doi: 10.3390/molecules18089704.
This work was objectively targeted to synthesize extremely pure triacylglycerols (TAG) enriched in conjugated linoleic acids (CLAs) for medical and dietetic purposes. Extremely pure CLA-enriched TAG was successfully synthesized by using the multi-step process: TAG was primarily synthesized by lipase-catalyzed esterification of CLA and glycerol and then the lower glycerides [monoacylglycerol (MAG) and diacylglycerol (DAG)] in the esterification mixtures was hydrolyzed to free fatty acids (FFAs) by a mono- and di-acylglycerol lipase (lipase SMG1), finally, the FFAs were further separated from TAG by low temperature (150 °C) molecular distillation. The operation parameters for the lipase SMG1-catalyzed hydrolysis were optimized using response surface methodology based on the central composite rotatable design (CCRD). The operation parameters included water content, pH and reaction temperature and all of these three parameters showed significant effects on the hydrolysis of lower glycerides. The optimal conditions were obtained with a water content of 66.4% (w/w, with respect to oil mass), pH at 5.7 and 1 h of reaction time at 19.6 °C. Under these conditions, the content of lower glycerides in the reaction mixture decreased from 45.2% to 0.3% and the purity of CLA-enriched TAG reached 99.7%. Further purification of TAG was accomplished by molecular distillation and the final CLA-enriched TAG product yielded 99.8% of TAG. These extremely pure CLA-enriched TAG would be used for in vivo studies in animals and humans in order to get specific information concerning CLA metabolism.
这项工作的目的是合成用于医学和饮食目的的富含共轭亚油酸（CLA）的超纯三酰基甘油（TAG）。通过使用多步工艺成功合成了超纯 CLA 富集的 TAG：通过脂肪酶催化 CLA 和甘油的酯化反应首先合成 TAG，然后通过单酰基和二酰基甘油脂肪酶（脂肪酶 SMG1）将酯化混合物中的较低甘油三酯（单甘油脂（MAG）和二甘油脂（DAG））水解为游离脂肪酸（FFA），最后，通过低温（150°C）分子蒸馏将 FFA 从 TAG 中进一步分离。使用基于中心组合旋转设计（CCRD）的响应面法优化了脂肪酶 SMG1 催化水解的操作参数。操作参数包括含水量、pH 值和反应温度，这三个参数对较低甘油三酯的水解均有显著影响。最佳条件为含水量为 66.4%（w/w，相对于油质量），pH 值为 5.7，反应时间为 19.6°C，反应时间为 1 小时。在这些条件下，反应混合物中较低甘油三酯的含量从 45.2%降低到 0.3%，CLA 富集的 TAG 纯度达到 99.7%。通过分子蒸馏进一步纯化 TAG，最终的 CLA 富集 TAG 产物得到 99.8%的 TAG。这些超纯 CLA 富集的 TAG 将用于动物和人体的体内研究，以获得有关 CLA 代谢的具体信息。
