Summary
The endogenous protease activity in various commercially available laundry
detergents of international companies was studied. The maximum protease activity
was found at 501C in pH range 10.5–11.0 in all the tested laundry detergents. The
endogenous protease activity in the tested detergents retained up to 70% on
incubation at 401C for 1 h, whereas less than 30% activity was only found on incubation
at 501C for 1 h. The alkaline protease from an alkalophilic strain of Bacillus cereus was
studied for its compatibility in commercial detergents. The cell free fermented broth
from shake flask culture of the organism showed maximum activity at pH 10.5 and
501C. The protease from B. cereus showed much higher residual activity (more than
80%) on incubation with laundry detergents at 501C for 1 h or longer. The protease
enzyme from B. cereus was found to be superior over the endogenous proteases
present in the tested commercial laundry detergents in comparison to the enzyme
stability during the washing at higher temperature, e.g., 40–501C.
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