Journal of Pure and Applied MicrobiologyVol. 3 No. 2

Thermostable Alkaline Protease from a Soil Isolate of Alkalophilic Bacillus species

C. Vijaya*, D. Vani, G. Jayabalan and A. Babu Thandapani

Pharmaceutical Biotechnology Laboratory, Centre for PG studies, Ultra College of Pharmacy, Madurai - 625 020, India.

Received on 18 February 2009 and accepted on 21 April 2009



A soil isolate of Bacillus species (UVV1) was identified to produce extracellular alkaline protease under submerged fermentation in shake flask culture. Casein digestion was followed for assaying the alkaline protease activity. The operation variables optimized for improved alkaline protease production were pH, temperature and incubation time. A pH of 9 and temperature range of 50°C - 60°C favour the growth of the isolate as well as the production of protease with highest activity. Protease production was increased as the incubation time was prolonged up to 120 hours except for the span of 48 – 72 hours when a reduction in enzyme activity was noticed. The characterization studies on the crude enzyme reveal that the proteolytic activity was maximum at pH 9 and temperature 60° C.

Keywords : acillus soil isolate, Alkaline protease, Casein digestion, Production optimization