Growth Kinetics of Aerobic Heterotrophic Bacteria and Cyanobacteria During Biodegradation of Total Petroleum Hydrocarbon in Bodo Creek

Abstract

Laboratory studies on resident aerobic heterotrophic bacteria and cyanobacteria isolated from crude oil contaminated Bodo creek characterized by moderate salinity was investigated for total petroleum hydrocarbon degradation using GC-FID (Agilent 6890 model). Monod's empirical expression to determine the specific growth rate based on the effect of the limiting substrate-total petroleum hydrocarbons. The growth of aerobic heterotrophic bacteria and cyanobacteria increased with decrease in TPH and its percentage loss in all the treatments monitored did not vary significantly with time using a one-way analysis of variance (ANOVA) (p>0.05). The values for the maximum specific growth rate (µm) and the saturation constant (K s) for the treatment were; aerobic heterotrophic bacteria, AHB µm = 0.02823day-1 , K s = 4229.61 mg/L; cyanobacteria, CB, µm = 0.01468 day-1 K s = 2130.21 mg/L, consortium of aerobic heterotrophic bacteria and cyanobacteria, AHB + CB, µm = 0.06085day-1 , K s = 1716.51 mg/L and the control, µm = 0.074033 day-1 , K s = 6200.71. The result obtained throughout the study implies that the consortium of aerobic heterotrophic bacteria and cyanobacteria had higher affinity for TPH having the lowest K s value of 1716.51 mg/L compared to the other treatment options.