SWAPNA GUNTUPALLI, LEELA MADHURI CHALASANI, KSHATRI JYOTHI, C.V. RAO B AND BONDILI J.S.
Abstract
The study hypothesizes that enhanced biodegradation of Polycyclic Aromatic Hydrocarbons (PAHs) is achievable with an assemblage of microorganisms that are capable of producing biofilm and biosurfactants. Accordingly, microorganisms were screened and grouped into consortia based on their capabilities to produce biofilm and biosurfactants. Consortium BTSN09 consists of microorganisms positive for either only biofilm or biosurfactant production or both, whereas KLSN09 consists of organisms producing both. Over a period of 42 days, BTSN09 showed 54% and 45% degradation of Phenanthrene (PHE) and Pyrene (PYR) while KLSN09 degraded only 28% and 18% of PHE and PYR with 200mg/L and 100 mg/L concentrations respectively in a liquid medium. In addition, the effect of additive surfactant Tween 80 showed an improved biodegradation to 95% for consortia with PHE and 35% for PYR in 21 days. Microbial consortia also demonstrated good biosurfactant production capacity, achieving maximum oil displacement area and emulsification activity of 19.62 cm2, 59% in presence of PAHs as sole carbon source. Scanning Electron Microscopy analysis revealed exopolysaccharides (EPS) production, micro and macrocolonies formation with different stages of biofim development in presence and absence of Tween 80. Overall, BTSN09 degraded PAHs efficiently compared to KLSN09.