Isolation and characterization of monoacetyldiglycerides from bovine udder

Monoacetyldiglycerides (MADGs) were isolated from an animal tissue, bovine udder, by solvent extraction and silica gel column chromatography, Monoacet yldiglyceride structures were identified using a variety of 1-D and 2-D NMR techniques and collision-induced dissociation (CID) tandem mass spectromet ry coupled with fast atom bombardment, CID of sodium-adducted molecular ion s ([M+Na](+)) generated numerous types of product ions providing informatio n on the double bond position of fatty acyl groups as well as fatty acid co mpositions. Structural analysis led to the classification of the MADGs isol ated from bovine udder as 1-palmitoyl-2-lauroyl-3-acetyl-rac-glycerol, 1,2- dimyristoyl-3-acetyl-rac-glycerol, 1-palmitoyl-2-myristoyl-3-acetyl-rac-gly cerol, 1-oleoyl-2-myristoyl-3-acetyl-rac-glycerol 1-palmitoyl-2-palmitoleoy l-3-acetyl-rac-glycerol, 1,2-dipalmitoyl-3-acetyl-rac-glycerol, 1-linoleoyl -2-palmitoyl-3-acetyl-rac-glycerol, 1-oleoyl-2-palmitoleoyl-3-acetyl-rac-gl ycerol, 1-oleoyl-2-palmitoyl-3-acetyl-rac-glycerol, 1-stearoyl-2-palmitoyl- 3-acetyl-rac-glycerol, 1-oleoyl-2-linoleoyl-3-acetyl-rac-glycerol, 1,2-diol eoyl-3-acetyl-rac-glycerol, and 1-stearoyl-2-oleoyl-3-acetyl-rac-glycerol.