Purification and characterization of detergent-compatible protease from Aspergillus terreus gr.

Abstract

The possibility of using Aspergillus terreus protease in detergent formulations was investigated. Sodium dodecyl sulfate (SDS) and native polyacrylamide gel electrophoresis indicated that the purified alkaline protease (148.9 U/mg) is a monomeric enzyme with a molecular mass of 16 ± 1 kDa. This was confirmed by liquid chromatography–mass spectrometry. The active enzyme degraded the co-polymerized gelatin. The protease demonstrated excellent stability at pH range 8.0–12.0 with optimum at pH 11.0. It was almost 100 % stable at 50 °C for 24 h, enhanced by Ca2+ and Mg2+, but inhibited by Hg2+, and strongly inhibited by phenylmethyl sulfonyl fluoride. It showed maximum activity against casein followed by gelatin; its Vmax was 12.8 U/ml with its corresponding KM of 5.4 mg/ml. The proteolytic activity was activated by Tween-80, Triton-100 and SDS, and remained unaltered in the presence of H2O2 and NaClO. The enzyme exhibited higher storage stability at 4, 28 and −20 °C. It was stable and compatible to the desired level in the local detergents. The addition of the protease to the Super wheel improved its blood stain removal. The isolated protease can thus be a choice option in detergent industry.

Characterization of the Crude Alkaline Extracellular Protease of Yarrowia lipolytica YlTun15

“…The average residual activity of the extracted protease showed a linear and significant decrease with pH drop. This result is consistent with that found for protease extracted from other micro-organisms (Kumar and Tagaki, 1999;Ma et al, 2007), but a higher pH value (11) was found for an optimal activity of protease from Aspergillus terreus (Niyonzima and More, 2015), which was also inactive at low pH. It was also reported that a large amount of alkaline protease could be secreted under neutral condition and three acids protease can be secreted by Y. lipolytica (Barth and Gaillardin, 1997).…”

“…Analogous results were found for the A. pullulan, A. terreus and B. subtilis , Niyonzima and More, 2015, and Alam et al, 2017.The inhibitory effect of mercury was due to the fact that it reacts with protein thiol groups and with histidine and tryptophan residues (Bezawada et al, 2011, Barth andGaillardin, 1997). The Cu 2+ and Mn 2+ cations seem to have an antagonistic effect on the enzyme activity ( Figure 5).…”

“…This decrease might be explained by the ice crystal formation that inactivates enzymes (Beena et al, 2012). Comparing to this result, Niyonzima and More (2015) found that for Aspergillus terreus the protease decrease with 9% after 40 days storage in -20°C.…”

“…Up to 5 mM, the protease activities in the presence of EDTA and SDS were 74% and 55% respectively. Correspondingly, proteases from Aspergillus terreus and Aspergillus tamari exhibited a stability in the presence of EDTA (Anandan et al, 2007, Niyonzima andMore, 2015). Such finding approve that Yarrowia lipolytica protease do not belong to the metalloprotein group, and could be of interest to the detergent industry as the stability of protease in the presence of chelating agents such as EDTA is a prerequisite for any detergent enzyme (Beg and Gupta, 2003).…”

Novel Protease from <i>Aspergillus tamarii</i> URM4634: Production and Characterization Using Inexpensive Agroindustrial Substrates by Solid-State Fermentation

“…Lineweaver-Burk plot of initial velocity of the extracellular protease from Aspergillus tamarii URM4634 is shown in Figure 3. The K M = 5.4 mg/mL were recorded for the detergent-compatible protease from Aspergillus terreus [32]. Ha et al [33] has reported a commercial protease with K M = 24.9 mg/mL the fungus 31K in the degradation of meat proteins.…”