STRAIN IMPROVEMENT OF RHIZOPUS-ORYZAE FOR PRODUCTION OF L(+)-LACTIC ACID AND GLUCOAMYLASE

Thirty-eight L(+)-lactic acid-overproducing mutants were isolated by mutagenizing a parent strain of Rhizopus oryzae NRRL 395 with u.v. and/or N-methyl-N'-nitro-N-nitrosoguanidine. Three mutants, 1N1, 3N4 and 3N6, were found to yield significantly more L(+)-lactic acid in a rice medium than the parent strain. Of the mutants examined, only mutant 3N4 produced more glucoamylase than the parent strain.