Biosurfactants are surface-active substances synthesized by microorganisms having the properties of reducing surface tension, stabilizing emulsions, promoting foaming and are generally non-toxic and biodegradable. Here an effort was made to screen biosurfactant activity of a protease producing bacteria isolated from municipal solid waste. Strain was identified as Pseudomonas aeruginosa by 16S rDNA based molecular technique. Biosurfactant, obtained from isolated organism was screened by hemolytic assay, drop collapsing method, oil spread method, blue agar plate method and oil spreading technique. In oil spread method kerosene oil shown the best result (58mm) and in emulsification index method petrol has given maximum efficient result (64 % in comparison to 1% of SLS having 58% EI). Besides biosurfactant activity the strain also produces protease enzyme. The strain has shown maximum protease activity at pH 9.5, temperature 37°C and 48 hrs. of incubation time. So, this strain can be used in textile, leather, detergent, pharmaceutical and dairy industries for its dual ability of producing protease enzyme and biosurfactant activity.
