Isolation and characterization of Penicillium funiculosum mutants with enhanced glucose oxidase production

After the mutagenesis of Penicillium funiculosum with UV light and N-nitroso-N-methylurea, 83 of 2237 grown colonies were surrounded with increased zones of glucose oxidase diffusion. Analysis of the glucose oxidase activity of selected mutant strains grown in submerged cultures allowed 18 mutant strains to be obtained whose glucose oxidase activity was 5-153% higher (in a medium with glucose) and 4-83% higher(in a medium with sucrose) than that of the parent strain. Two of these mutant strains, UV6.31 and NMU95-132, possessed high glucose oxidase activity when grown in media with glucose or sucrose and produced large amounts of mycelia. The active and morphologically stable mutant P. funiculosum NMU95-132 was chosen for further selection work.