Fig. 8

a Inhibition of phosphatase activity (PA), reported as IU per g of cell proteins, by adding different amount of PO4−3 in NaC medium under aerobic (solid circles) and anaerobic (empty circles) condition. b Determination of PA in NaC medium with Ag+, Hg2+ and Pd2+ additions (50 mg.l− 1) under aerobic (solid histograms) and anaerobic condition (empty histograms). Standard deviation values are reported as vertical bars