Fatty acids of bovine milk glycolipids and phospholipids and their specific distribution in the diacylglycerophospholipids

Abstract

Milk lipids were fraetionated by silicic acid column chronlatography and preparative thinlayer chromatography [TLC). Ceramide monohexoside (CMH), eeramide dihexoside (CDH), phosphatidyl ethanolamine (PE), phosphatidyl choline (PC), phosphatidyl serine (PS), and ~phingomyelin (Sph) were isolated, and the purity of each was checked by infrared spectroscopy and TLC. The diacylphospholipids were hydrotyzed with phospholipase A and the products separated by TLC. Fatty acid methyl esters were prepared from the various fractions and analyzed by gas chromatography.The glycolipids, CMH and CDH, and Sph contained large amounts of long-chain saturated fatty acids, especially C2.,:., C2:~:., and C,,4:,.PE, PS, and PC contained C~o-C,,,, normal and branched-chain saturated fatty acids, and C15-'C2o unsaturated fatty acids (mainly monoenes). The distributions of saturated acids between the a'-and B-positions were respectively : PE, 46 and 11%; PS, 65 and 19%; and PC, 72 and 53%. PC was exceptional in that there was 10.8% myristie acid in the B-position and only 5.6% in the a'-position. PE and PS were similar in composition except that in PE oleic acid was evenly distributed, and in PS was largely in the B-position. In general, PC was much more saturated than PE or PS, and there was no overall pattern governing the specific distribution of the fatty acids in the three diaeylphospholipids. Comparison with PC from other bovine tissues and from egg lecithin showed that fatty acids are located much less specifically in milk phospholipids than in PC from other sources.

Comparison of dairy phospholipid preparative extraction protocols in combination with analysis by high performance liquid chromatography coupled to a charged aerosol detector

“…These elution patterns are in agreement with those described by Deschamps et al (2001) and Fagan and Wijesundera (2004). Sub-peaks for both bovine PC and milk fat SM standards were observed due to the large number of molecular species that exist of which lipid chemists have been aware of for many years (Christie, Noble, & Davies, 1987;Karlsson, Michelsen, & Odham, 1998;Morrison, Jack, & Smith, 1965).…”

Identification and Quantitative Analysis of Phospholipids in Cocoa Beans

“…Phosphatidyl inositol and phosphatidyl serine were separated by Skipski et al (1964), but cardiolipin and phosphatidic acid could not be differentiated. Morrison et al (1965) used two solvent systems on two separate plates to resolve most of the polar lipids from bovine milk but phosphatidyl inositol was not separated in their study.…”

Composition lipidique d'un sous-produit de lactosérum de caséinerie

“…Des glucocéramides témoins (Sigma) contenant 98% d'acides gras hydroxylés migrent à une distance inférieure à celle observée pour CMH de PLP (migration non représentée). L'ordre de migration des lipides polaires de PLP diffère légèrement de celui donné par Morrison et al (1965), avec ce système de solvants. L'inversion constatée pour PE et CDH rapproche nos résultats de ceux V Ducruet et al rapport acides gras saturés : acides gras insaturés voisin de celui obtenu pour PC mais sa composition s'en distingue par une proportion plus faible de C14:0 et de C16:0, qui est compensée par la présence d'environ 28% d'acides gras à longue chaîne, pour l'essentiel, saturés (C22:0 à C24:0).…”

“…Systèmes de migration chromatographique sur couche mince pour l'étude des lipides de la poudre Iipoprotéique (PLP). Systèmes l, Il et 111*: d'aprèsWolff et al (1984); Système IV* : d'aprèsSkipski et Barclay (1969); Système V : d'aprèsMorrison et al (1965). * : pour ces 2 systèmes, le front du solvant 2 est arrêté à 2 cm en dessous du front du solvant 1. systems used for Iipid thin layer chromatography from Iipoproteic powder (PLP).…”

“…Influence du type d'hydrolyse. a : selonMorrison et al (1965) : babeurre, transméthylation par BF 3 -méthanol 90 min à 100 oC; b: selonMorrison et Hay (1965) : babeurre, saponification puis méthylation par BF 3 -méthanol 24 h à 110°C; C : selonKayser et Patton (1970) : membrane du globule gras, transméthylation par HCI-méthanol 18 h-24 h à 80 oC; d : pourcentage relatif exprimé par rapport à la somme des acides gras rapportés dans le tableau. Pour l'intérêt de la comparaison, les sommes des acides gras provenant des références bibliographiques sont ramenées à 100. ces acides à longue chaîne.…”