keywords: Aspergillus oryzae, Optimization, Mannolyitc enzymes, β-1,4-mannosidase, Solid State Fermentation
Refined and complex mannan-containing substrates were investigated for their ability to induce β-1,4-mannosidase enzyme production in Aspergillus oryzae PT4 in a solid substrate fermentation condition, while optimizing the fermentation process using the best complex carbon source and One Factor at Time (OFAT) approach. Various carbon, nitrogen sources and some environmental factors were varied and enzyme titre assayed. Regulation of enzyme production in this organism was also studied in the presence of 0.2g of easily utilizable sugars per gram of the complex carbon source. Copra meal was the best carbon source after Locust Bean Gum. Addition of nitrogen source while using copra meal reduced the amount of enzyme produced by this isolate. The pH of 5.0, moisture content of 100% v/v, inoculum size of 8% v/v, temperature of 30 oC and incubation time of 10 days were the best fermentation condition for the production of β-1,4-mannosidase by Aspergillus oryzae PT4. Mannosidase enzyme production in this isolate was highly inductive. Using the above set of conditions, enzyme titre was optimized from 39.24±0.19 to 87.55±3.80 U/gds.