Enzymic hydrolysis of diol lipids by pancreatic lipase

Chain length and positional specificities of pancreatic lipase for diol lipids have been examined by use of the synthetic substrates such as the diol esters and related esters that contain C6--C20 even-numbered saturated acids and oleic acid as fatty acids, and ethylene glycol, 1,2- and 1,3-propanediols, 1,3-, 1,4-, and 2,3-butanediols, monohydric alcohols, and glycerol as alcohols. No remarkable difference in the degree of hydrolysis was observed in the case of diol esters having C14--C20 fatty acids at least during 30-min digestion, though hydrolysis reached a maximum in diol diotanoates after the same period. Pancreatic lipase specifically released only the fatty acids esterified with the primary hydroxyl groups of diols.