ATP CONTENT IN ACTIVATED-SLUDGE

The ATP content in activated sludge was investigated using the boiled HEPES buffer extraction method. The ATP contents in different sludge s amples ranged from 0.2 to 1.5 mg.g-dry wt.-1, and corresponded to 7.7 to 57% of the contents of microorganisms at the logarithmic growth pha se (average 2.6 mg.g-dry wt.-1). A good correlation (r=0.701) was obse rved between the ATP contents and the oxygen consumption rates (V(A)) of activated sludge samples. The ATP content remained constant for up to 12 hours in an activated sludge sample stored at 4-degrees-C.