Fatty acid composition of leaf lipids determined after combined digestion and fatty acid methyl ester formation from fresh tissue

Abstract

A procedure which uses hot methanolic HCl to digest fresh tissue and simultaneously convert the fatty acids of the leaf lipids to the corresponding methyl esters is described. Extraction of the fatty acid methyl esters into a small volume (0.3 ml) of hexane means that a sample for GLC analysis can be taken directly from the tube used for the digestion/methylation reaction. The procedure provides a fatty acid analysis which is comparable to that obtained by a more conventional technique involving separate extraction, saponification, and methylation steps, but the overall yield is reduced by 10-20%. The analysis can be made quantitative by including an internal standard with the tissue sample.