Production, purification and characterization of protease by aspergillus flavus under solid state fermentation

الملخص EN

Protease production under solid state fermentation (SSF) was investigated using isolated Aspergillus flavus.

Different agroindustrial waste products were evaluated to check the possibility of potential utilization of substrates in SSF for protease production by Aspergillus flavus using wheat bran as a substrate.

The results showed that the optimum conditions for maximum protease production were found to be 7th day of incubation at pH 5.0, temperature 30oC ; inoculum size 3% ; substrate concentration 3 % and 3 % KNO3 as nitrogen source.

The purified enzyme produced 5.8 fold with recovery of 3.2 % by DEAE-column chromatography and the molecular weight was estimated to be 46kDa by SDS-PAGE.

It has a Vmax value of 60.0 U / mg and Km value of 0.6 mg/ml at pH of 7.

The enzyme activity was found to be stable at 500 C and it was stimulated by metal ions like Cu2+ and Zn2+ and inhibited by Ca2+ and Mg 2+.