Open AccessA simple 14 C‐respirometric method for assessing microbial catabolic potential and contaminant bioavailability
Author(s) -
Reid Brian J,
MacLeod Christopher J.A.,
Lee Philip H,
Morriss Alistair W.J.,
Stokes Joanna D,
Semple Kirk T
Publication year - 2001
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2001.tb10555.x
Subject(s) - respirometer , phenanthrene , environmental chemistry , chemistry , bioavailability , respirometry , biodegradation , soil contamination , naphthalene , chromatography , soil water , environmental science , soil science , organic chemistry , biology , bioinformatics , oxygen
This paper describes the validation and application of a simple flask‐based 14 C‐respirometer system designed to assess mineralisation of 14 C‐labelled substrates under defined conditions. Validation of this respirometer system indicated stoichiometric CO 2 trapping up to a maximum of 400 μmol of CO 2 (in a single trap). Polycyclic aromatic hydrocarbon (PAH)‐degrading bacteria were used to measure growth‐linked biodegradation of [ 14 C]naphthalene to 14 CO 2 . A 14 C activity balance of 101.7±8.9% ( n =6 ), after 74 h incubation time and 10 respirometer‐opening events, indicated the suitability of the system for monitoring substrate mineralisation. This respirometric apparatus was then successfully applied to assess: (i) the PAH catabolism of microbes in a field contaminated soil, where naphthalene and phenanthrene were rapidly mineralised and (ii) soil‐associated organic contaminant bioavailability, where increased soil–phenanthrene contact time resulted in a reduction in phenanthrene mineralisation in the soil. The described respirometer system differs from existing respirometer systems in that the CO 2 trap can be removed and replaced quickly and easily. The system is efficient, reproducible, adaptable to many situations, easy to construct and simple to use, it therefore affords advantages over existing systems.