Periodical batch culture of the immobilized growing fungi Sporotrichum cellulophilum producing cellulase in the nonwoven materials.

The thermophilic fungus Sporotrichum cellulophilum was immobilized with nonwoven materials for cellulase production. The cellulose powder concentration in the medium was an important factor controlling cellulase production. When the cellulose powder concentration in the nonwoven materials was more than 4%, cellulase production was suppressed. The growth of the immobilized fungi depended on the spaces in the nonwoven materials. Immobilized growing fungi were retained by the non-woven materials, and the supernatant medium did not contain mycelia. The heat stability of the immobilized growing fungus was higher than that of the free fungus. The immobilized fungus gave the same FPA as the free mycelium, but the lag time for cellulase production in the immobilized fungus was longer. It was necessary for the only medium to be changed in order to get the immobilized growing fungus to continue producing cellulase. In this instance there was no difference of lag time in comparison with the free cells, and the supply of cellulose powder and polypepton was reduced to two-thirds. After 23 exchanges of the medium (2.6 mg cellulose powder/1 cm(3) nonwoven materials) FPA value was maintained. The periodic batch culture was continued for 69 days.