http://link.springer.com/article/10.1007/s10532-013-9644-3

Andrea Bagi, Daniela M. Pampanin, Anders Lanzén, Torleiv Bilstad, Roald
Kommedal
Naphthalene biodegradation in temperate and arctic marine microcosms
Biodegradation
February 2014, Volume 25, Issue 1, pp 111-125
DOI 10.1007/s10532-013-9644-3
Abstract: Naphthalene, the smallest polycyclic aromatic hydrocarbon
(PAH), is found in abundance in crude oil, its major source in marine
environments. PAH removal occurs via biodegradation, a key process
determining their fate in the sea. Adequate estimation of PAH
biodegradation rates is essential for environmental risk assessment and
response planning using numerical models such as the oil spill
contingency and response (OSCAR) model. Using naphthalene as a model
compound, biodegradation rate, temperature response and bacterial
community composition of seawaters from two climatically different areas
(North Sea and Arctic Ocean) were studied and compared. Naphthalene
degradation was followed by measuring oxygen consumption in closed
bottles using the OxiTop® system. Microbial communities of untreated and
naphthalene exposed samples were analysed by polymerase chain reaction
denaturing gradient gel electrophoresis (PCR–DGGE) and pyrosequencing.
Three times higher naphthalene degradation rate coefficients were
observed in arctic seawater samples compared to temperate, at all
incubation temperatures. Rate coefficients at in situ temperatures were
however, similar (0.048 day−1 for temperate and 0.068 day−1 for arctic).
Naphthalene biodegradation rates decreased with similar Q10 ratios (3.3
and 3.5) in both seawaters. Using the temperature compensation method
implemented in the OSCAR model, Q10 = 2, biodegradation in arctic
seawater was underestimated when calculated from the measured temperate
k1 value, showing that temperature difference alone could not predict
biodegradation rates adequately. Temperate and arctic untreated seawater
communities were different as revealed by pyrosequencing. Geographic
origin of seawater affected the community composition of exposed samples.
Keywords: Hydrocarbons; Naphthalene; Biodegradation; Q10;
Pyrosequencing; DGGE; Seawater