Ultrasound-assisted improvements in biocatalytic activity and production of organic-solvent stable protease from Bacillus circulans MTCC 7942

This study reports the ultrasound-assisted improvements in biocatalytic activity and production of protease from organic solvent-tolerant, alkaliphilic Bacillus circulans MTCC 7942. The strain withstands 10 min ultrasound treatment (33 kHz); this treatment promotes the growth of bacterium. The protease production was improved by 1.5-fold on multiple ultrasound treatment at 0, 6, 12 h intervals. Although the substrate casein remains unaffected by ultrasound treatment (33 kHz, 10 min); the treatment had boosted the enzyme activity of purified protease. Also, the ultrasound treated purified protease showed enhancement in enzyme activity in presence of n-dodecane, n-octane, n-hexadecane, n-decane, xylene, butanol, toluene, pyridine and chloroform.