A rapid method for stereospecific glyceride analysis and its application to soybean and oat varieties

摘要

Rapid methods for the analysis of glyceride structure were explored so they could be applied to the determination of the extent of variation in glyceride structure of oilseed crops and possible use in oil crop breeding. For analysis of the sn-2-position of glycerol and the generation of diglycerides for stereospecific analysis, a method was adopted in which pancreatic lipase hydrolysis of the triglycerides and subsequent separation of the mono- and diglycerides was achieved on one thin layer silica gel plate;Attempts to phosphorylate diglycerides for stereospecific analysis of the glycerides on thin layer plates either with the enzyme diglyceride kinase or phenyldichlorophosphate were unsuccessful. But if the diglycerides were phosphorylated with phenyldichlorophosphate in a test tube, the phosphatide that were formed could be hydrolyzed with snake venom and the products separated on a single thin layer silica gel plate. These procedures made a reasonably rapid method possible;These methods were applied to a number of varieties and plant introductions of soybeans, Glycine max, and a closely related wild species, Glycine soya. A number of oat varieties, Avena sativa, and a closely related wild species, Avena sterilis, were also analyzed. The results were similar to those previously reported for soybeans and other oilseed plants. There was a linear relationship between the amount of a fatty acid on a particular position of glycerol and the amount of the fatty acid in the whole oil. Lines were fitted to the data by linear regression. None of the varieties and introductions tested varied widely from the linear relation. The plants deviating most from the linear relations need to be advanced a generation and retested to determine if the variation is genetic or environmental.