DHA-rich medium- and long-chain triacylglycerols (MLCT) were produced by lipase-catalyzed acidolysis of microbial oil from Schizochytrium sp. with medium-chain fatty acids (MCFA). Four commercial lipases, i.e., NS40086, Novozym 435, Lipozyme RM IM, and Lipozyme TL IM were screened based on their activity and fatty acid specificity. The selected conditions for MLCT synthesis were Lipozyme RM IM as catalyst, reaction time 6 h, lipase load 8 wt%, substrate molar ratio (MCFA/microbial oil) 3:1, and temperature 55 °C. Under the selected conditions, the lipase could be reused successively for 17 cycles without significant loss of lipase activity. The obtained product contained 27.53% MCFA, 95.29% at sn-1,3 positions, and 44.70% DHA, 69.77% at sn-2 position. Fifty-nine types of triacylglycerols (TAG) were identified, in which 35 types of TAG contained MCFA, the content accounting for 55.35%. This product enriched with DHA at sn-2 position and MCFA at sn-1,3 positions can improve its digestion and absorption under an infant’s digestive system, and thus has potential to be used in infant formula to increase the bioavailability of DHA.

富含DHA的中链和长链三酰基甘油（MLCT）是通过脂肪酶催化的裂殖壶菌属微生物油的酸解而产生的。与中链脂肪酸（MCFA）。根据它们的活性和脂肪酸特异性，筛选了四种商业脂肪酶，即NS40086，Novozym 435，Lipozyme RM IM和Lipozyme TL IM。MLCT合成的选择条件为Lipozyme RM IM作为催化剂，反应时间6 h，脂肪酶负载8 wt％，底物摩尔比（MCFA /微生物油）3：1和温度55°C。在所选条件下，脂肪酶可连续重复使用17个循环，而不会显着降低脂肪酶活性。获得的产物包含27.53％的MCFA，在sn -1,3位置的95.29％和44.70％的DHA，在sn的69.77％-2位置。鉴定出59种三酰基甘油（TAG），其中35种TAG含有MCFA，含量为55.35％。该产品在sn -2位置富含DHA，在sn -1,3位置富含MCFA，可以改善其在婴儿消化系统下的消化吸收，因此有潜力用于婴儿配方食品中以提高DHA的生物利用度。