Enhancement of PAH biomineralization rates by cyclodextrins under Fe(III)-reducing conditions.
Amendment of a soil slurry with low concentrations of a cyclodextrin, hydroxypropyl-beta-cyclodextrin (HPCD), (0.05-0.5 g l(-1)) increased the phenanthrene mineralization rate of a microbial consortium by 25% under Fe(III)-reducing conditions. Although a higher concentration (5.0 g l(-1)) resulted in a faster initial rate of mineralization, mineralization ceased after 25 days with maximum mineralization 17% lower than the control (no HPCD). At lower HPCD concentrations, mineralization was still taking place at day 76. Although pH should affect Fe(III) solubility, mineralization rates at pH 6.0 and 8.0 were comparable. Decreasing the temperature reduced the extent and rate of mineralization, but mineralization rates at 10 degrees C were still 60% of that obtained at 30 degrees C.
Ramsay
Juliana A
JA
Department of Chemical Engineering, Queen's University, Kingston, Ont., Canada K7L 3N6. ramsayj@chee.queensu.ca
Robertson
Kevin
K
vanLoon
Gary
G
Acay
Nick
N
Ramsay
Bruce A
BA
D000073738:2-Hydroxypropyl-beta-cyclodextrin; D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D003033:Coal Tar; D005290:Ferric Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry / Q000378:metabolism*; D012989:Soil Pollutants / Q000378:metabolism*; D012995:Solubility; D047392:beta-Cyclodextrins / Q000737:chemistry*
D005290:Ferric Compounds; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; D047392:beta-Cyclodextrins; D000073738:2-Hydroxypropyl-beta-cyclodextrin; D003033:Coal Tar