Studies on Distribution of Biosurfactant Producing Bacteria in Contaminated and Undisturbed Soils of Kanchipuram

Ever increasing environmental concern about chemical surfactants triggers attention to microbial derived surface-active compounds, essentially due to their low toxicity and biodegradable nature. At present, biosurfactants are predominantly used in remediation of pollutants, in the enhanced transport of metabolites in bacteria, in enhanced oil recovery, as cosmetic additives, in biological control. However, little is known about the distribution and prevalence of biosurfactant-producing bacteria in the environment. The primary objective of this study was to determine how common culturable surfactant producing bacteria are present in contaminated and undisturbed soil samples in and around Kanchipuram (12°50ʹ23"N 79°42ʹ0"E), Tamilnadu, India. A series of each 5 contaminated and undisturbed soils were collected and plated on R2A agar. Totally, 155 morphologically different bacterial isolates were obtained and qualitatively screened for biosurfactant production in mineral salts medium containing 2% glucose. Out of 155 isolates, eight isolates were positive for biosurfactant production, representing most of the soils tested. Quantitative estimation of surface activity identified two potent biosurfactant producing strains Bacillus sp.BS3 and Pseudomonas sp. Maximum surface activity was observed to be 26.58 x 10-3 nm-1 and 20.60 x 10-3 nm-1 respectively for Bacillus sp.BS3 and Pseudomonas sp. BS5. The present study is a preliminary demonstration that the Indian soils are rich in biosurfactant producing bacteria, which can be exploited for industrial production of biosurfactants