Biodegradation Effects of Crude Oil-Polluted Water Using Bacteria Isolates From Sunflower Husk on Fish Growth: Parametric Optimization Using Taguchi Approach

Abstract

Bacteria isolates from sunflower husk were applied for bioremediation of crude oil-contaminated water.Fish weight was monitored in bioremediated water by gravimetric method. Taguchi design matrix was employed for process parameters optimization, which include reaction temperature (20-60oC), inoculums concentration (20-100 CFU/mL), crude oil concentration (50-250 mL/L), reaction time (1-5 hrs), NH4Cl concentration (20-100 mg/L) and K3PO4 concentration (10-50 mg/L) for crude oil degradation and fish growth. Bacteria isolates were characterized by biochemical tests. Water samples were characterized using gas chromatograph-mass spectroscopy (GC-MS), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and carbon-hydrogen-nitrogen (CHN) analysis. Results revealed optimum crude oil degradation of 96.59 ± 0.03 % for 50 mL/L of crude oil in water supplemented with 100 CFU/mL inoculums, 10 mg/L K3PO4 and 10 mg/L NH4Cl at 60oC reaction temperature and 4 hrs reaction time. Also, optimum fish growth of 93.14 ± 0.04 % was achieved in 50 mL/L of crude oil in solution supplemented with 80 CFU/mL inoculums, 10 mg/L K3PO4 and 20 mg/L NH4Cl at 60oC reaction temperature and 5 hrs reaction time. Conclusively, characterization revealed degradation of hydrocarbons in crude oil-contaminated water from heavy into light fractions by the bacteria isolates.