Abstract
An extra-cellular thermo-alkaliphillic protease producing Bacillus was isolated from the soil and identified to be Bacillus tequilensis MTCC 9585 by microscopic, colony morphology, biochemical and 16S ribotyping. B. tequilensis MTCC 9585 produces protease up to 21 h of growth but interestingly 90% of the protease production occurred, just after 6 h of growth. The organism grew as well as and produced enzyme at wide pH (5 to 12) and temperature range (4, 25, 37 and 50°C), though optimum temperature and pH for the growth of the Bacillus were 37°C and pH 7.0. Optimum pH for enzyme activity coincided with optimum pH for enzyme production at pH 10. Optimum temperature for enzyme activity was 60°C and the enzyme stayed stable over the period of 270 days (9 months) at 10°C. Metal ions like Ca2+, Mg2+, K+ increased the enzyme activity whereas Cu2+, Zn2+inhibit the activity slightly. Wash performance and stain removal efficiency increased when partially purified enzyme was used in conjunction with selected detergent. B. tequilensiscan be a potential candidate for use in detergent industry because: of couple of reasons such as (i) 90% of the protease is produced only after 6 h of growth (economically viable), (ii) it’s activity in wide pH and temperature range (iii) it’s stability over the period of 9 months at 10°C indicating good shelf life and (iv) detergent compatibility. Key words: Bacillus tequilensis, alkaline protease, pH, temperature, detergent compatibility.
Highlights
Commercial proteases are produced by various bacteria and about 35% of the total microbial enzymes used in detergent are from bacterial sources (Huang et al, 2006)
Detergents are used at elevated washing temperatures, but currently there is considerable interest in the identification of alkaline proteases, which are effective over a wide temperature and pH range
We report isolation of thermostable, alkaliophilic protease produced by Bacillus tequilensis MTCC-9585 and its stability as well as the activity in the presence of commercial powered detergents
Summary
Commercial proteases are produced by various bacteria and about 35% of the total microbial enzymes used in detergent are from bacterial sources (Huang et al, 2006). Various species of Bacillus produce a variety of extracellular and intracellular protease (Beison et al, 2000; Huang et al, 2003; Nascimento et al, 2006; Rao et al, 2007). Bacillus is otherwise an attractive microbial producer for variety of reasons, including their high growth rates leading to short fermentation cycles, production of extracellular proteins and are regarded as GRAS (Generally regarded as safe) industrial tool. Licheniformis and Subtilisin Novo produced by Bacillus amyloliquefaciens have been the enzymes of choice in detergent so far (Horikoshi, 1990). We report isolation of thermostable, alkaliophilic protease produced by Bacillus tequilensis MTCC-9585 and its stability as well as the activity in the presence of commercial powered detergents
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
