Isolation and Characterization of Hexadecane Degrading Bacteria from Oil- polluted soil in Gio Community, Niger Delta, Nigeria

Abstract

This study investigated the presence of viable indigenous hexadecane degraders in chronically polluted soil in Gio community, Niger Delta. Crude oil-polluted samples were collected from the four GPS coordinate points at depth of 0-0.15m (Gio polluted surface soil [GPS]), 1m (Gio polluted subsurface soil [GPSS]) respectively and Gio unpolluted control soil (GUPS) was collected from approximately 1000m away from the polluted site. Gas chromatography - flame ionization detector (GC-FID) analysis for total petroleum hydrocarbon (TPH) were 36,776 ppm, 14,100 ppm, 480 ppm for GPS, GPSS and GUPS respectively. Polycyclic aromatic hydrocarbon (PAHs) concentrations determined were 12,210 ppm, 3,250 ppm, 23 ppm for GPS, GPSS and GUPS respectively. Total cultivable hydrocarbon utilizing bacterial count (TCHUB) for GPS, GPSS and GUPS were 6.6 × 105cfu/g, 6.4 × 105cfu/g and 3.96 × 104cfu/g respectively. Out of the 22 bacteria isolated and characterized from the crude oil enrichment method, Pseudomonas sp. (65 %), Bacillus sp. (66%), Achromobacter sp. Proteus sp.(45%) and Serratia sp (40%). demonstrated higher biodegradation potential for hexadecane using 2,6-dichlorophenol indophenols (DCPIP) redox indicator. In conclusion the extant autochthonous bacteria are metabolically active, can effectively degrade hexadecane and could be good candidates for bioremediation.