Membrane microfiltration fermentation of glucose oxidase with cell recycling

Membrane microfiltration fermentation (MMF) with cell recycling was success fully applied to the production of glucose oxidase (GOD). A plate microfilt ration module was found suitable for such purpose. By feeding whole medium in MMF, the productivity of GOD was much higher than that by feeding glucos e alone. With increasing dilution rate the enzyme productivity increased an d average enzyme activity decreased. The enzyme productivity of MMF under D = 0.12 h(-1) and 0.20 h(-1) were 3871 and 3945 U h(-1) respectively, which was about 3 times as that of batch fermentation (BF) and the average enzym e activity was still as high as 37 U.mL(-1) under D = 0.12 h(-1). The relat ive efficiency of MMF applied to low yield strain was higher than that appl ied to high yield strain.