Purification, Characterization and De-Staining Potentials of a Thermotolerant Protease Produced by Fusarium oxysporum

Abstract

Proteases are important industrial enzymes and fungi prove to be good sources of such enzymes. Purification techniques are however necessary for increased specificity in activity and better industrial value. Based on this, a protease produced by a Fusarium oxysporum was purified to homogeneity by Sephadex G-200 column and α–casein agarose chromatography. The enzyme had a molecular weight of 70 kDa in SDS-PAGE. Purified Fusarium oxysporum protease had a specific activity of 93.88 U/mg protein. The purification magnitude was 7.7 and the total yield was 20 %. Purified protease had an optimum pH of 5.0 while the optimum temperature was 40 °C. The enzyme was also thermotolerant (approximately 100 % at 40 °C for 2 h). The enzyme activity was stimulated by surfactants and metal ions like, Tween-20 and Mg2+. Enzyme activity was inhibited in presence of PMSF and EDTA. Casein was found to be the best substrate for protease activity of Fusarium oxysporum FWT1. Protease were tested upon blood stain for de-clotting of blood and was found to exhibit good de-clotting and de-staining activity after 15 minutes treatment time.