A mathematical approach to lipolysis based on the interrelationship of physicochemical and biochemical data

A novel approach is described for the quantitation of the parameters involved in lipolytic activity. The activity of lipase purified from human pancreatic juice against an oil-water emulsion depends on the degree of emulsification, the type of emulsifier used, the type and the concentration of bile salt, the concentration of colipase and, finally, on the ζ-potential of the interface. The ζ-potential, in turn, depends on the partition of bile salt molecules between the micellar state in the bulk and their adsorption on the oil-water interface. None of these parameters correlates straightforward with lipase activity. However, if several parameters are taken into account, the enzyme activity determined in our system obeys a multiparametric equation where the variables are: the conjugation of bile salts, the number of hydroxy groups, their aggregation number and, finally, the ζ-potential of the oil droplets.