BIOMASS RELATIONSHIP TO GROWTH AND PHOSPHATE-UPTAKE OF PSEUDOMONAS-FLUORESCENS, ESCHERICHIA-COLI AND ACINETOBACTER RADIORESISTENS IN MIXED LIQUOR MEDIUM

The ability of Pseudomonas fluorescens, Escherichia coli and Acinetoba cter radioresistens to remove phosphate during growth was related to t he initial biomass as well as to growth stages and bacterial species, Phosphate was removed by these bacteria under favourable conditions as well as under unfavourable conditions of growth, Experiments showed a relationship between a high initial cell density and phosphate uptake , More phosphate was released than removed when low initial cell densi ties (10(2)-10(5) cells ml(-1)) were used, At a high initial biomass c oncentration (10(8) cells ml(-1)), phosphate was removed during the la g phase and during logarithmic growth by P. fluorescens, Escherichia c oli, at high initial biomass concentrations (10(7) cells ml (1)), accu mulated most of the phosphate during the first hour of the lag phase a nd/or during logarithmic growth and in some cases removed a small quan tity of phosphate during the stationary growth phase, Acinetobacter ra dioresistens, at high initial cell densities (10(6), 10(7) cells mi (1 )) removed most of phosphate during the first hour of the lag phase an d some phosphate during the stationary growth phase, Pseudomonas fluor escens removed phosphate more than A. radioresistens and E. coli with specific average ranges from 3.00-28.50 mg L(-1) compared to average r anges of 4.92-17.14 mg L(-1) for A. radioresistens and to average rang es of 0.50-8.50 mg L(-1) for E. coli.