Screening And Characterization Of Biosurfactant-Producing Bacteria Isolated From Mechanic Workshop Soil In Umuahia Metropolis:- Okezie Oluchi

ABSTRACT Biosurfactants are amphiphilic surface active agents produced by microorganisms. They are complex molecules comprising a wide variety of chemical structure; their hydrophilic part is usually composed ofsugars, amino acids and carboxylic acid groups. This study-screened and characterized bio-surfactant producing bacteria species isolated from contaminated mechanic workshop in Umuahia metropolis. A total of five (5) samples were collected from the selected mechanic workshops and cultured on nutrient agar, mannitol salt agar, and blood agar using spread plate techniques. In the present study a total of ten (10) bacterial strains were isolated and identified using their biochemical characteristics, and cultural morphology. The potential biosurfactant-producing isolates were confirmed to be affiliated to the genus Bacillus sp, Acinetobacter sp, Psuodomonas sp, and Flavobacterium sp. The preliminary screening for biosurfactant production show that only genus Bacillus was able to produce biosurfactant. A total of eight (8) isolates exhibited beta-haemolysis ability while two (2) of the isolates were non-beta haemolytic organisms. The drop-collapse assay showed that only eight (8) out of the ten (10) bacterial isolates were positive while two isolates showed negative result. It was also revealed in this study that isolates S2 (A) of the genus Bacillus had the highest percentage index at (50%); followed by Acinetobacter and Pseudomonas aeruginosa, which recorded 47.5% each. The ability of these bacteria species to synthesize biosurfactant with 50% emulsification index, suggest its potential application in environment clean up procedures.