title: ABTS assay of phenol oxidase activity in soil.
abstract: Phenol oxidases (PO) are involved in degradation of many recalcitrant aromatic compounds and may be sensitive to some pollutants. Hence, their activities may be a useful indicator for evaluating soil quality and health. To this end, the aim of this study was to develop a simple method to assay PO activity directly in bulk samples by spectrophotometric test using 2,2'-azinobis-(-3 ethylbenzothiazoline-6-sulfononic acid) diammonium salt (ABTS) as the substrate. Three Mediterranean soils were used as models. For each soil, we studied the kinetic parameters and the effects of certain factors (i.e. amount of soil, pH, temperature, incubation time and substrate concentration) in order to determine the optimum conditions for the ABTS assay. Results showed that PO attain their optimum activities when incubating 0.1 g of soil at 30 degrees C for 5 min with 10 ml of a Modified Universal Buffer (MUB) at pH 2 and 200 microl of a 0.1 M ABTS solution.
authors.affiliation: Institut Méditerranéen d'Ecologie et de Paléoécologie, UMR CNRS 6116, Equipe d'Ecologie Microbienne, Case 452, Université Paul Cézanne Aix-Marseille III, Faculté des Sciences et Techniques de Saint-Jérôme, Marseille, France. carine.floch@univ-cezanne.fr
authors.forename: Carine
authors.initials: C
authors.lastname: Floch
authors.forename: Enrique
authors.initials: E
authors.lastname: Alarcon-Gutiérrez
authors.forename: Stéven
authors.initials: S
authors.lastname: Criquet
mesh_terms: D052160:Benzothiazoles / Q000378:metabolism*; D001681:Biological Assay; D002021:Buffers; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D014442:Monophenol Monooxygenase / Q000737:chemistry / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D013451:Sulfonic Acids / Q000378:metabolism*; D013696:Temperature
chemical_list: D052160:Benzothiazoles; D002021:Buffers; D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D014442:Monophenol Monooxygenase