Assessment of indigenous bacterial isolates for diesel biodegradation potential (T-1581) (MFN 8631)

Abstract

Worldwide, utilization of diesel as a fuel possesses significant threats to aquatic and terrestrial environment. Being mobile and toxic in nature, it causes adverse effects o exposed mechanisms. The objective of the study was to isolate and examine efficiencies of indigenous bacterial isolates in a batch experiment. 15 Isolates were screened according to their capabilities to survive in harsh diesel environment. A series of experiments were conducted using incubator shaker containing MSM, bacteria along with diesel. The screened isolates were tested with 1% (10000mg/L) and 3% (30000mg/L) (v/v) diesel to check their potential. A consortium for the best isolates was also tested in a similar fashion to investigate the degradation trend. Results of 16srRNA identified that the best isolates, A1 and E5, were Bacillus sp, with accession number MK583607 and MK387180 respectively. The Monod model applied for bacillus species utilizing as a substrate showed maximum specific bacteria growth was 0.1131 1/hr for E5 while at 3% dose it was 0.1287 1/hr. While for the strain A1 it was 0.0522 1/hr. The degradation characteristics of strain E5 in 3% (v/v) diesel were analyzed using GC-MS. The analysis results unraveled, Bacillus strain E5 capabilities to almost degrade all components of diesel oil, with a degradation ratio of up to 60% after 16 hours of incubation at 37 in MSM. The diesel oil utilized as a major carbon source had hydrocarbon ranging between C11–C27. All the compounds had been depleted with favorable consumption of C14, Tetrad cane with removal of 88%, followed by Hexadecane C16 which was 75%. The results indicated that both the species had the capabilities to consume diesel as a substrate especially E5 and having the capabilities to bio remediate hydrocarbon polluted sites