Identification of alkyldiacylglycerols containing saturated methyl branched chains in the Harderian gland of guinea pig.

More than 90% of total lipids in the Harderian gland of guinea pig was identified as 1-alkyl-2,3-diacylglycerol. The alkyl and acyl moieties consisted of saturated aliphatic chains ranging from 14 to 21 carbon atoms and from 15 to 26 carbon atoms, respectively. About 60 mol% of them had methyl branches, which were located at the even-numbered carbon atoms. Mono- and di-methyl branched chains accounted for most of the branched chains. The aliphatic chains contained methyl branches especially in the alkyl chains at the 1-position and the acyl chains at the 2-position