Studies on the Detergency of Phosphate-Free Detergents for Home-Use

Part 7 : Oily Soil Removal in the Formulation of Protease and Lipase

Abstract

Using the phosphate-free detergents formulated with protease and lipase, the effects of stability of lipolytic enzyme, lipase, in the washing solution on the removal of oily soils from cotton fabric were investigated at pH 9.5, 30°C.
1) Activities of two kinds of lipases originated from Rhizopus and Mucor, were reduced by anionic surfactants, and stabilized by adding nonionic polymers.
2) The removal of oleic acid and triolein were promoted in the solution of sodium sulfite as an alkaline reduction agent.
3) Nonpolar triolein was removed effectively in lipase solution containing reducing agent and PVA caused by their synergistic effects.
4) In the model formulations of detergent, protease/lipase/DBS systems, oily soils were removed not only by the actions of hydrolysis of lipase but also by those of synergistic effects caused by interactions between oily soils and other soil, such as protein, on the fabric, and by interactions between the soils and formulated compounds.