Novel applications of crude bacterial biosurfactant

Abstract

The present study was aimed to produce economically viable biosurfactant with novel applications. A total of 23 bacterial cultures isolated from mangrove sediment and garden compost samples on nutrient agar medium were tested for the prroduction of biosurfactant by growing in Mineral salt medium with 1 percent mineral oil as sole carbon sourcefor 24-48 h and the amount of biosurfactant was quantified by the standard Orcinol method using L-rhamnose as standard. Ten isolates selected as potential based on maximum amount of biosurfactant production were used and the crude biosurfactant produced by them were further subjected for various confirmation studies such as oil spread method, hemolysis test, drop collapse test, blue agar plate method and emulsification activity. The antimicrobial (against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Proteus vulgaris) and anti-biofilm activities (against pre-formed Bacillus subtilisbiofilm) of crude biosurfactant from all the ten isolates were investigated. Biosurfactant from two novel isolates identified as Bacillus sp and Klebsiella sp showed positive for maximum confirmation tests and also exhibited promising anti-bacterial and anti-biofilm activities. Thus,the present study recommends the use of crude biosurfactant as a potential alternative to chemical surfactantsmaking theirapplication a cost-effectiveand sustainable use.