Microorganisms produced biosurfactants are promising agents in the bioremediation of pesticide polluted soils as a result of their biodegradability and non-toxic nature. This study was aimed at screening bacteria for biosurfactant production in pesticide contaminated agricultural soil, and identify them using molecular technique. Ten bacteria species with potentials to degrade lambda-cyhalothrin isolated in our previous study were screened for biosurfactant production via the drop collapse, oil spreading, emulsification index, hydrocarbon overlay agar and bacterial adhesion to hydrocarbon tests. The biosurfactant producers were identified using the 16S rRNA. Results from the biosurfactant screening showed that out of the ten bacteria screened only four of the ten bacteria screened which were identified as Bacillus strains were strongly positive for production of biosurfactant. The four Biosurfactant-Producing Lambda Cyhalothrin- Degrading Bacteria (LCDB-BP) were identified using 16S rRNA as Bacillus tequilensis strain LCDB-BP1, Bacillus subtilis strain LCDB-BP2, Bacillus altitudinis strain LCDB-BP3, and Bacillus subtilis strain LCDB-BP4 with the accession numbers OP703607, OP703608, OP703609 and OP703610 respectively. These organisms can be useful for biosurfactant production and bioremediation of synthetic pyrethroid contaminated soil.

Keywords : Biosurfactant, Synthetic Pyrethroids (SP), Lambda-cyhalothrin (LC), Bacillus species, cultivated soil.