<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Alkaline protease production, extraction and characterization from alkaliphilic <i style="mso-bidi-font-style:normal">Bacillus licheniformis</i> KBDL4: A Lonar soda lake isolate</span>

Abstract

A bacterium producing an alkaline protease was isolated from the Lonar soda lake, Buldhana district (19°58' N; 76°31' E), Maharashtra, India. The most appropriate medium for the growth and protease production was composed of (g/L): casein 10; yeast extract 4; KH₂PO₄ 0.5, K₂HPO₄ 0.5 and CaCl₂0.5. The enzyme showed maximum activity with and without 5 m<i style="mso-bidi-font-style: normal">M</i> Ca²⁺ at 70 and 60 ^oC, respectively. The enzyme retained 40 and 82% of its initial activity after heating for 60 min at 60 ^oC, in absence and presence of 5 m<i style="mso-bidi-font-style:normal">M</i> CaCl₂respectively. The enzyme remained active and stable at <i style="mso-bidi-font-style:normal">p</i>H 8-12, with an optimum at <i style="mso-bidi-font-style:normal">p</i>H 10. The enzyme showed stability towards non-ionic and anionic surfactants, and oxidizing agents. It also showed excellent stability and compatibility with commonly used laundry detergents. Wash performance analysis revealed that enzyme could effectively remove blood stains. It also showed decomposition of gelatinous coating on X- ray film.