Effect of hybridization on the production of cellulolytic enzymes by aspergillus niger

ABSTRACT

Two non cellulolytic auxotrophic mutants of Aspergillus niger were crossed together. From 20 obtained prototrophs, the segregants of 4 only could give prototrophs indicating that they were stable heterocaryons or diploids. The 4 prototrophs grew well and produced true cellulolytic activity on avicel as a sole carbon source. Cellulase production by the 4 isolates growing in liquid medium in shaken flask cultures has been investigated. In general A. niger isolates were found to be inducible for the enzymes of the cellulase complex [exoglucanase, endoglucanase, and B-glucosidase], and isolate No I was the most potent mold, and it showed about 3 fold that in B-glucosidase production [8.851 unit/ml] when Na NO[3]was used as a nitrogen source