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Biodegradation of alkyl branched aromatic alkanoic naphthenic acids by Pseudomonas putida KT2440

Johnson, Richard J and Smith, Ben E and Rowland, Steven J and Whitby, Corinne (2013) 'Biodegradation of alkyl branched aromatic alkanoic naphthenic acids by Pseudomonas putida KT2440.' International Biodeterioration & Biodegradation, 81. pp. 3-8. ISSN 0964-8305

Johnson et al 2011 (IBB) finalrevised.pdf

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The majority of the world's crude oil reserves consist of highly biodegraded heavy and super heavy crude oils and oil sands that have not yet been fully exploited. These vast resources contain complex mixtures of carboxylic acids known as naphthenic acids (NAs). NAs cause major environmental and economic problems, as they are recalcitrant, corrosive and toxic. Although aromatic acids make up a small proportion of most NA mixtures, they have demonstrable toxicities to some organisms (e.g. some bacteria and algae) and ideally need to be removed or reduced by remediation. The present study analysed the ability of Pseudomonas putida KT2440 to degrade highly recalcitrant aromatic acids, as exemplified by the alkyl phenylalkanoic acid (4'-t-butylphenyl)-4-butanoic acid (t-BPBA) and the more degradable (4'-n-butylphenyl)-4-butanoic acid (n-BPBA). n-BPBA was completely metabolized after 14 days, with the production of a persistent metabolite identified as (4'-n-butylphenyl)ethanoic acid (BPEA) which resulted from removal of two carbon atoms from the carboxyl side chain (beta-oxidation) as observed previously with a mixed consortium. However, when n-BPBA concentration was increased two-fold, degradation decreased by 56% with a concomitant six-fold decrease in cell numbers, suggesting that at greater concentrations, n-BPBA may be toxic to P. putida KT2440. In contrast, P. putida KT2440 was unable to degrade the highly recalcitrant t-BPBA even after 49 days. These findings have implications for NA bioremediation in the environment. © 2011.

Item Type: Article
Uncontrolled Keywords: Beta-oxidation; Naphthenic acids; Bioremediation
Subjects: Q Science > QH Natural history > QH301 Biology
Divisions: Faculty of Science and Health
Faculty of Science and Health > Life Sciences, School of
SWORD Depositor: Elements
Depositing User: Elements
Date Deposited: 26 Jan 2012 15:24
Last Modified: 05 Apr 2022 06:38

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