title: Acute effect of benzo[a]anthracene on the biodegradation of peptone under aerobic conditions.
abstract: BACKGROUND
  This study investigated the acute effect of benzo[a]anthracene, a significant compound among polycyclic aromatic hydrocarbons, on the biodegradation of a synthetic organic substrate-a peptone/meat extract mixture-under aerobic conditions.
  
  
  METHODS
  A laboratory-scale sequencing batch reactor was sustained at steady state at a sludge age of 10 days with substrate feeding. Inhibition tests involved running a series of batch reactors initially seeded with the biomass obtained from the parent reactor. After the biomass seeding, the reactors were started with the peptone mixture and a range of initial benzo[a]anthracene concentrations between 0.5 and 88 mg/L. Experimental profiles of oxygen uptake rates and polyhydroxyalkanoates were evaluated by calibration of a selected model.
  
  
  RESULTS
  Lower doses of benzo[a]anthracene had no effect on process kinetics. The noticeable acute impact was only observed with the addition of 88 mg/L of benzo[a]anthracene, but it was limited with the storage mechanism: the amount of organic substrate diverted to polyhydroxyalkanoates was significantly reduced with a corresponding decrease in the maximum storage rate, k (STO), from 2.7 down to 0.6 day(-1). Similarly, the maximum growth rate from internally stored polyhydroxyalkanoates was lowered from 2.3 to 1.0 day(-1).
  
  
  CONCLUSIONS
  Among the mechanisms for direct substrate utilization, only the hydrolysis rate was slightly reduced, but otherwise, the overall COD removal efficiency was not affected.
authors.affiliation: Department of Environmental Engineering, Faculty of Engineering and Architect, Campus of Avsar, Kahramanmaraş Sütçü Imam University, 46100 Kahramanmaraş, Turkey.
authors.forename: Serden
authors.initials: S
authors.lastname: Başak
authors.forename: Emine Ubay
authors.initials: EU
authors.lastname: Cokgör
authors.forename: Güçlü
authors.initials: G
authors.lastname: Insel
authors.forename: Derin
authors.initials: D
authors.lastname: Orhon
mesh_terms: D001551:Benz(a)Anthracenes / Q000378:metabolism*; D057919:Biological Oxygen Demand Analysis; D010100:Oxygen / Q000378:metabolism; D010461:Peptones / Q000378:metabolism*; D054813:Polyhydroxyalkanoates / Q000378:metabolism; D012722:Sewage / Q000382:microbiology
chemical_list: D001551:Benz(a)Anthracenes; D010461:Peptones; D054813:Polyhydroxyalkanoates; D012722:Sewage; C030935:benz(a)anthracene; D010100:Oxygen