The Peroxidase-Mediated Biodegradation of Petroleum Hydrocarbons in a H2o2-Induced Sbr Using In-Situ Production of Peroxidase: Biodegradation Experiments and Bacterial Identification Publisher Pubmed



Shekoohiyan S¹ ; Moussavi G¹ ; Naddafi K²
Source: Journal of Hazardous Materials Published:2016

Abstract

A bacterial peroxidase-mediated oxidizing process was developed for biodegrading total petroleum hydrocarbons (TPH) in a sequencing batch reactor (SBR). Almost complete biodegradation (>99%) of high TPH concentrations (4 g/L) was attained in the bioreactor with a low amount (0.6 mM) of H2O2 at a reaction time of 22 h. A specific TPH biodegradation rate as high as 44.3 mgTPH/gbiomass×h was obtained with this process. The reaction times required for complete biodegradation of TPH concentrations of 1, 2, 3, and 4 g/L were 21, 22, 28, and 30 h, respectively. The catalytic activity of hydrocarbon catalyzing peroxidase was determined to be 1.48 U/mL biomass. The biodegradation of TPH in seawater was similar to that in fresh media (no salt). A mixture of bacteria capable of peroxidase synthesis and hydrocarbon biodegradation including Pseudomonas spp. and Bacillus spp. were identified in the bioreactor. The GC/MS analysis of the effluent indicated that all classes of hydrocarbons could be well-degraded in the H2O2-induced SBR. Accordingly, the peroxidase-mediated process is a promising method for efficiently biodegrading concentrated TPH-laden saline wastewater. © 2016 Elsevier B.V.