ABSTRACT
Using the methods of surface balance we compared surface activity of different natural phosphatidylcholines. Dipalmitoylphosphatidylcholine, the principal component of natural surfactant, is characterized by less rapid spreading on the air-water interface compared to unsaturated yolk and soybean phosphatidylcholines, while the absolute rate of surface tension reduction was the same for all test lecithines. The surface activity of modified saturated soybean phosphadtidylcholine (Phospholipon) was similar to that of dipalmitoylphosphatidylcholine. The relationship between saturation of fatty acids in the molecule of phosphatidylcholine and the time of spreading on the air-water interface revealed in this study allows to use this parameter together with equilibrium surface tension for evaluation of surface activity when testing synthetic surfactant constituents.
