Abstract
In order to develop the admicellar system, lipase from Candida rugosa was immobilized into an admicellar system consisting of silica gel and nonionic surfactant, Triton X-100. Adsorption mechanism of lipase on the admicelles was different from bare silica gel. On bare silica, multilayer adsorption of lipase molecules was supposed due to a scarce affinity to the silica surfaces. On the other hand, in the case of admicelles, the adsorption isotherm of lipase was well correlated with the Langmuir model. Such transformation of isotherms was not observed in the case of lysozyme. These behaviors were explained by two aspects; electrostatic interaction due to the isoelectric point of both enzymes and surface charge of silica gel, and affinity originated in hydrophobicities of enzyme surface. From H.F.S. values, it was presumed that the surface of lipase from Candida rugosa was relatively hydrophobic and lysozyme had a rather hydrophilic surface. In addition, activity of lipase could be maintained in Triton X-100 layers on silica gel after washing by buffer solution.
