• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.189-196
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• 2010

The removal of phosphorus (P) in the wastewater is essential for the prevention of eutrophication in the river and stream. This study was initiated to evaluate the effect of the various heavy metals on the growth and P removal capacity of Pseudomonas sp., which was well known as phosphorus accumulating microorganism(PAO's) in the EBPR(Enhanced Biological Phosphorus Removal) process. The five heavy metals used in the study were Cu, As, Zn, Ni, and Cd. The growth rate of Pseudomonas sp. was the greatest at $25^{\circ}C$, but the removal efficiency of P was the highest at $30^{\circ}C$. The $IC_{50}$ (median Inhibition Concentration) values of Pseudomonas sp. for the Cu, As, Zn, Ni, and Cd were 2.35, 11.04, 1.80, 4.92, and 0.24 mg/L, respectively. Therefore, it appears that the sensitivity of the heavy metals to Pseudomonas sp. was in the following order: Cd> Zn> Cu> Ni> AS. Also, the P removal efficiencies by Pseudomonas sp. were correspondingly decreased as the concentrations of heavy metals were increased.

• Korean Journal of Environmental Agriculture
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• v.31 no.2
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• pp.185-191
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• 2012

Background: The removal of phosphate(P) in the wastewater is essential for the prevention of eutrophication in the river and stream. This study was initiated to evaluate the P removal by three strains of bacteria isolated from industrial wastewater. The three strains of bacteria, A1, A2, and A3, isolated were identified as Stenotrophomonas maltophilia strain CUPS 3, Rhodococcus erythropolis strain Sco-C01, Bacillus sp. 3434BRRJ, respectively. METHODS AND RESULTS: The experiments evaluating the effects of temperature, P concentration, aeration, and carbon sources on P removal by Bacillus sp. 3434BRRJ were performed in the following conditions: temperature, 15, 25 and $30^{\circ}C$; P concentrations, 20, 30, and 40 mg/L; oxygen condition, aerobic, anaerobic/aerobic conditions; carbon sources, glucose, acetate and mixture of glucose and acetate. As a result, the best optimum conditions for P removal by Bacillus sp. 3434BRRJ were as follows: temperature, $30^{\circ}C$; P concentration, 20 mg/L; carbon sources, mixture of glucose and acetate; oxygen concentration, anaerobic and aerobic conditions. The P removal efficiencies by Bacillus sp. 3434BRRJ, Stenotrophomonas maltophilia strain CUPS, and Rhodococcus erythropolis strain Sco-C01 were 99%, 50%, 20%, respectively. CONCLUSION: As a result, the best optimum conditions for P removal by Bacillus sp. 3434BRRJ selected and used in this study were as follows: temperature, $30^{\circ}C$; P concentration, 20 mg/L; carbon sources, mixture of glucose and acetate; oxygen concentration, anaerobic and aerobic conditions.