The aim of this study was to investigate the prediction of C-14-phenanthrene and C-14-hexadecane biodegradation in the presence of other hydrocarbons in soil using beta- and alpha-cyclodextrin (CD) solutions, respectively. Prediction of the biodegradation of C-14-phenanthrene using the P-CD extraction was robust under single, co-contaminant and multiple contaminant conditions (r(2) = 0.92, slope of best fit line = 0.87, intercept = 7.24, n = 84). Prediction of C-14-hexadecane using the alpha-CD extraction was robust under single and co-contaminant conditions (r(2) = 0.92, slope of best fit line=0.97, intercept=1.24, n = 60); however, the alpha-CD could not accurately predict C-14-hexadecane biodegradation in the presence of multiple contaminants. The presence of multiple contaminants enhanced C-14-hexadecane mineralisation, but did not enhance extractability. The results from this study provide further evidence for the application of HPCD extractions for the measurement of microbial accessibility in soil. (C) 2008 Elsevier Ltd. All rights reserved.
- cyclodextrin extraction technique
- microbial availability
- organic contaminants
- PAH bioavailability