A simple and effective method has been developed for the immobilization of lipase producing Rhizoupus chinensis on polyurethane foam. In this method the fungal cells with 1-3 specific lipase in their inside are immobilized within the foam matrix. Four types of commercially available polyurethane foam were tested. The ultimate purpose of the process is to produce low-cost biocatalysts for lipase-catalyzed reactions which are being increasingly used for industrial applications.
Effects of several parameters were studied on the cell loading and the hydrolytic activity of intracellular lipase after acetone drying. These parameters were the type, size, and amount of polyurethane foam. In all the cases the intracellular lipase activity obtained with the foam was approximately twice greater than that obtained in the absence of the foam. For the hydrolysis test an olive oil emulsion was used as the feed. Effects of pH, temperature and the concentration of $CaCl_2$ were also investigated on the hydrolytic activity. It was observed that the optimum pH, temperature, and $CaCl_2$ concentration were 7.4, 37℃, and 0.027 (w/v %), repectively.