Docosahexaenoic acid

Neat arachidonic acid, docosapentaenoic acid, and docosahexaenoic acid were obtained from NuChek Prep (Elysian, MN). d8-arachidonic acid and d5-docosahexaenoic acid were purchased from Cayman Chemicals (Ann Arbor, MI). 17:0a/20:4a-PC, 17:0a/20:4a-PE, 17:0a/20:4a-PG, 17:0a/20:4a-PI, 17:0a/20:4a-PS, 17:0a/20:4a-PA, 21:0a/22:6a-PC, 21:0a/22:6a-PE, 21:0a/22:6a-PG, 21:0a/22:6a-PI, 21:0a/22:6a-PS, and 21:0a/22:6a-PA in methanol were purchased from Avanti Polar Lipids (Alabaster, AB). Pentafluorobenzyl bromide (PFB) and N,N-diisopropylethylamine (DIEA) were obtained from Sigma-Aldrich (St. Louis, MO).

TWM was obtained from Qianjin Xieli Pharmaceutical Co., Ltd (Hunan, China). TP (>98% pure) was provided by Guilin Sanjin Biologics Co., Ltd (Guanxi, China). Docosahexaenoic acid (C22:6n3), docosanoic acid (C22:0), eicosapentaenoic acid (C20:5n3), eicosatrienoic acid (C20:3n6), arachidonic acid (C20:4n6), arachidic acid (C20:0), nonadecadienoic acid (C19:2n6), γ-linolenic acid (C18:3n6), α-linolenic acid (C18:3n3), linoleic acid (C18:2n6), oleic acid (C18:1n9), cis-vaccenic acid (C18:1n7), stearic acid (C18:0), palmitic acid (C16:0), palmitoleic acid (C16:1n7), myristic acid (C14:0) and lauric acid (C12:0) were purchased from Nu-Chek Prep (Elysian, MN, USA). Their purities were above 98%. Trimethylsilane diazomethane (TMSCHN₂) in n-hexane (2 mol/L) was purchased from Energy Chemical (Shanghai, China). The other chemical reagents were purchased from Xilong Scientific Co., Ltd (Guangdong, China).