Relationship between the activity of soybean lipoxygenase 1 and the physicochemical characteristics of model food emulsion systems

The paper describes the relationship between the physicochemical characteri stics of model oi-in-water emulsion systems containing oil droplets and sol uble fragments (monomers and micelles) and the activity of pure soybean lip oxygenase 1. The method of emulsification, as well as the chemistry and con centration of surfactant and substrate molecules, was manipulated to modify the overall physicochemical properties of ternary emulsions. The effect of these experimental factors on the size and relative concentration of oil d roplets and soluble fragments was examined with static light scattering and turbidity measurements. Lipoxygenase 1 activity was assayed polarographica lly. Experimental factors that increase the critical micelle concentration of the monomers and facilitate their transport out of micelles, as well as across the oil-water interfaces and into the aqueous phase, were shown to i mprove the activity of the enzyme and vice versa.