PRODUCTION OF ORGANIC-ACIDS BY IMMOBILIZED FILAMENTOUS FUNGI

This article reviews current knowledge of the production of organic acids by immobilized filamentous fungi. The most widely used methods of immobilization are based on the adsorption and entrapment of the fungal cells. A variety of carriers have been employed but the open-porous materials and polymers with controlled characteristics are most suitable. Further elucidation of the mechanisms of interaction between cells and carriers may increase control of immobilization procedures. In general, immobilized systems show higher productivity than freely suspended cells and fluidized-bed reactors enable long-term operation of highly aerobic fermentations. The performance of the immobilized filamentous fungi is significantly affected by the nature and age of the cells, medium composition and process parameters, but published work merely describes such effects, with little information on underlying mechanisms.