PENICILLIUM-NOTATUM-1 A NEW SOURCE OF DEXTRANASE

Two hundred and fifteen fungal strains were screened for extracellular dextranase production with a diffusion plate method. The best enzymat ic activity (12-19 DU ml(-1)) was achieved by Penicillium notatum 1, a species for which the dextranase productivity has not yet been publis hed. Some of the parameters affecting enzyme production have been stan dardized. The enzyme in crude state was relatively stable, its maximal activity was at 50 degrees C and at pH 5.0. Conidia of the selected s train were mutagenized, and isolated mutants were tested for productio n of dextranase in submerged culture. The most active mutant, P. notat um 1-I-77, showed over two-times higher dextranase activity than the p arent P. notatum 1.