Abstract

Abstract The detection of arylsulfatases (enzymes that hydrolyze aryl sulfates) in soils is reported, and a simple method of assaying soil arylsulfatase activity is described. This method involves colorimetric estimation of the p ‐nitrophenol released by arylsulfatase activity when soil is incubated with buffered (pH 5.8) potassium p ‐nitrophenyl sulfate solution and toluene at 37C for 1 hour, and it is rapid, sensitive, and precise. The procedure used to extract p ‐nitrophenol stops arylsulfatase activity, develops the yellow color used to estimate p ‐nitrophenol, and gives quantitative recovery of this compound. Studies of the properties of the arylsulfatases in soils are reported.