초록
<P><B>Research highlights</B></P><P>► This is first report on statistical optimization of β-keratinase enzyme production and purification from <I>Brevibacillus</I> sp. AS-S10-II strain. ► An alkaline β-keratinase (Brevicarnase) with molecular mass of 83.2kDa displayed optimum activity at 45°C and pH 12.5. ► Brevicarnase demonstrated application oriented properties such as excellent thermostability, compatibility with commercial laundry detergents at a concentration of 0.1% (v/v) and dehairing activity suggesting its inclusion in commercial laundry detergent formulations and in leather- industry as eco-friendly dehairing agent.</P> <P><B>Abstract</B></P><P>Present study is the first report on production and purification of β-keratinase enzyme from a bacterium belongs to the genus <I>Brevibacillus</I>. The response surface optimized alkaline β-keratinase production by this strain was achieved as 923.0×10<SUP>3</SUP>Ul<SUP>−1</SUP> post 48h of incubation. An alkaline β-keratinase (Brevicarnase) having molecular mass of 83.2kDa purified from this strain showed optimum activity at 45°C and pH 12.5, respectively. The <I>K</I><SUB>m</SUB> and <I>V</I><SUB>max</SUB> values of β-keratinase towards keratin were determined as 0.3mgml<SUP>−1</SUP> and 4.5μmolmin<SUP>−1</SUP>mg<SUP>−1</SUP>, respectively. The Brevicarnase demonstrated appreciable thermo-stability and stability in the presence of anionic and non-ionic surfactants, oxidizing and bleaching agents, EDTA, and compatibility with the tested commercial laundry detergents at a concentration of 0.1%. The purified β-keratinase did not show collagen-degrading activity however, demonstrated dehairing property when tested on goat skin. These properties reinforce the feasibility of inclusion of Brevicarnase in laundry detergent formulations and in leather-industry.</P>