Phosphatase activity in anaerobic bioreactors for wastewater treatment.

Phosphatase (PO4ase) activity was investigated in continuous and fed-batch anaerobic bioreactors for wastewater treatment. PO4ase levels were high in continuously fed reactors (880-2632 micromol/L/h), compared to a fed-batch reactor (FBR) (540-1249 micromol/L/h). Alkaline and acid PO4ases were present in all the reactors, but in varying magnitudes and total PO4ase activity exhibited a 10-30% variation even at steady-state reactor conditions. The PO4ase activity was not affected by the inorganic phosphate (Pi) level in the reactors, but biomass level and wastewater type, including specific PO4ases (either alkaline or acid), strongly influenced the PO4ase activity in a reactor. Both flocculated and suspended cells produced PO4ase, and 60-65% of the enzyme was cell bound, remaining entrapped in the extracellular matrix and in cell-free form. Batch studies with anaerobic sludge showed a negative correlation between Pi and PO4ase activity. An increase in PO4ase activity was observed under starvation and higher salinity (above 15 g/L). Glucose and propionate (at 10 mM level) induced PO4ase activity, whereas acetate and butyrate (10 mM) addition had no response. This study also reveals that Archaea and bacteria contributed 45% and 55%, respectively, of total PO4ase activity in anaerobic sludge.

[1]  Y. Bashan,et al.  Recent advances in removing phosphorus from wastewater and its future use as fertilizer (1997-2003). , 2004, Water research.

[2]  E. Sakshaug,et al.  Alkaline phosphatase activity of Skeletonema costatum populations in the Trondheimsfjord , 1983 .

[3]  C. Lim.  The effect of environmental factors on the physiology of Aeromonas hydrophila in lake water , 1995 .

[4]  T. J. Hurst,et al.  Acid and alkaline phosphatase activity in anaerobic digested sludge: A biochemical predictor of digester failure , 1981 .

[5]  Yin Li,et al.  Microbial enzymatic activities in aerobic activated sludge model reactors , 2006 .

[6]  B. Pletschke,et al.  The enzymology of sludge solubilisation utilising sulphate reducing systems: Properties of proteases and phosphatases , 2002 .

[7]  K. Chitra,et al.  The Buoyant Filter Bioreactor: a high-rate anaerobic reactor for complex wastewater--process dynamics with dairy effluent. , 2005, Water research.

[8]  R. Wetzel,et al.  Effects of Photosynthesis on Bacterial Phosphatase Production in Biofilms , 2001, Microbial Ecology.

[9]  G. Guibaud,et al.  Relations between extraction protocols for activated sludge extracellular polymeric substances (EPS) and complexation properties of Pb and Cd with EPS: Part II. Consequences of EPS extraction methods on Pb2+ and Cd2+ complexation , 2006 .

[10]  R. Clément,et al.  Influence of phosphate ions and alkaline phosphatase activity of cells on survival ofEscherichia coli in seawater , 1990, Microbial Ecology.

[11]  P. Nielsen,et al.  Enzymatic activity in the activated-sludge floc matrix , 1995, Applied Microbiology and Biotechnology.

[12]  R. Özkanca,et al.  The effects of osmotic stress on survival and alkaline phosphatase activity of Aeromonas hydrophila , 1996 .

[13]  J. Block,et al.  Availability of low and high molecular weight substrates to extracellular enzymes in whole and dispersed activated sludges , 2002 .

[14]  P. Ginestet,et al.  Transfer of organic matter between wastewater and activated sludge flocs. , 2001, Water research.

[15]  P. E. Jørgensen,et al.  Enzyme activities in waste water and activated sludge , 1992 .

[16]  Michael A. Bull,et al.  The distribution of bacterial activity in an anaerobic fluidized bed reactor , 1984 .

[17]  H. Lemmer,et al.  Population density and enzyme activities of heterotrophic bacteria in sewer biofilms and activated sludge , 1994 .

[18]  A. Farnet,et al.  Annual dynamics of phosphatase activities in an evergreen oak litter: influence of biotic and abiotic factors. , 2004 .

[19]  T. Mino,et al.  Estimation of the rate of slowly biodegradable COD (SBCOD) hydrolysis under anaerobic, anoxic and aerobic conditions by experiments using starch as model substrate , 1995 .

[20]  B. Eliosov,et al.  Hydrolysis of particulate organics in activated sludge systems , 1995 .

[21]  L. Macaskie,et al.  Cadmium accumulation by a Citrobacter sp. , 1984, Journal of general microbiology.

[22]  G. Geesey,et al.  Localization and Identification of Populations of Phosphatase-Active Bacterial Cells Associated with Activated Sludge Flocs , 1999, Microbial Ecology.

[23]  A. Wilkins.  Physiological Factors in the Regulation of Alkaline Phosphatase Synthesis in Escherichia coli , 1972, Journal of bacteriology.

[24]  Aleksieva,et al.  Regulation of extracellular acid phosphatase biosynthesis by phosphates in proteinase producing fungus Humicola lutea 120-5. , 2000, Enzyme and microbial technology.

[25]  J. Raheb,et al.  Alkaline phosphatase activity of Flexibacter chinensis under starvation stress in water microcosms , 2006 .

[26]  R. Amann,et al.  Combination of 16S rRNA-targeted oligonucleotide probes with flow cytometry for analyzing mixed microbial populations , 1990, Applied and environmental microbiology.

[27]  L. Masse,et al.  Effect of hydrolysis pretreatment on fat degradation during anaerobic digestion of slaughterhouse wastewater , 2003 .

[28]  J. Content,et al.  The cell surface associated phosphatase activity of Mycobacterium bovis BCG is not regulated by environmental inorganic phosphate. , 2001, FEMS microbiology letters.

[29]  O. H. Lowry,et al.  A method for the rapid determination of alkaline phosphates with five cubic millimeters of serum. , 1946, The Journal of biological chemistry.

[30]  R. Ozkanca.  Survival and physiological status of Escherichia coli in lake water under different nutrient conditions , 1993 .

[31]  Linda M. M. Thompson,et al.  Biochemical Localization of Alkaline Phosphatase in the Cell Wall of a Marine Pseudomonad , 1974, Journal of bacteriology.

[32]  Zhiguo Yuan,et al.  Advances in enhanced biological phosphorus removal: from micro to macro scale. , 2007, Water research.

[33]  P. Stewart,et al.  Spatial Patterns of Alkaline Phosphatase Expression within Bacterial Colonies and Biofilms in Response to Phosphate Starvation , 1998, Applied and Environmental Microbiology.

[34]  T. Mino,et al.  Enzyme activities under anaerobic and aerobic conditions in activated sludge sequencing batch reactor , 1998 .

[35]  A. Pandit,et al.  Enhancement in biodegradability of distillery wastewater using enzymatic pretreatment. , 2006, Journal of environmental management.

[36]  A. Torriani,et al.  Influence of inorganic phosphate in the formation of phosphatases by Escherichia coli. , 1960, Biochimica et biophysica acta.