Watanabe Yomi, Sato Shinichi, Asada Mihoko, Arishima Toshiharu, Iida Yasuhiro, Imagi Jun, Saito Katsuyoshi, Sano Takashi, Sasaki Akiko, Sasaki Ryo, Sato Chiemi, Shibuya Tadahisa, Tsukahara Yuki, Nagai Toshiharu, Fukazawa Toru, Hori Ryuji, Homma Rika, Miyazaki Yosuke, Yamashita Atsushi, Yoshinaga Kazuaki, Watanabe Shimpei
Osaka Municipal Technical Research Institute.
J Oleo Sci. 2015;64(11):1193-205. doi: 10.5650/jos.ess15182.
The positional distributions of fatty acids (FAs) in fats and oils are principally analyzed by selectively transesterifying the target triacylglycerols (TAGs) at the 1(3) position using Pseudozyma (Candida) antarctica lipase, followed by recovering the resulting 2-monoacylglycerols (MAGs) by chromatography. FA compositions were measured by gas chromatography (GC) after methylating target TAGs and 2-MAGs. The method was collaboratively evaluated by 12 laboratories by analyzing the positional FA distributions in soybean, palm, and sardine oils. The maximum reproducibility relative standard deviations for the major FAs and those at the sn-2 positions of soybean, palm, and sardine oils were 4.41% and 3.92% (18:3n-3), 4.48% and 3.82% (18:0), and 8.93 and 8.24% (14:0), respectively. The values at the sn-2 position were always low. Therefore, these results indicated that the variations were mainly caused by the FA analysis procedure, i.e., the methylation and GC analyses, rather than the enzymatic transesterification and chromatography utilized to prepare 2-MAGs from the target oil.
油脂中脂肪酸(FAs)的位置分布主要通过使用南极假丝酵母脂肪酶在1(3)位选择性地对目标三酰甘油(TAGs)进行酯交换,然后通过色谱法回收生成的2-单酰甘油(MAGs)来分析。在对目标TAGs和2-MAGs进行甲基化后,通过气相色谱(GC)测量FA组成。通过分析大豆油、棕榈油和沙丁鱼油中的位置FA分布,12个实验室对该方法进行了协同评估。大豆油、棕榈油和沙丁鱼油中主要FAs以及sn-2位FAs的最大重现性相对标准偏差分别为4.41%和3.92%(18:3n-3)、4.48%和3.82%(18:0)以及8.93和8.24%(14:0)。sn-2位的值始终较低。因此,这些结果表明,变化主要是由FA分析程序,即甲基化和GC分析引起的,而不是由用于从目标油制备2-MAGs的酶促酯交换和色谱法引起的。