Screening Of A Phosphorus-accumulating Bacteria Strain,and Study On Its Biological Characteristics

As one of the elementary resources for all the humans and living things,water has been polluted seriously and become eutrophication in recent years,which leads the challenge of shortage of water resource and water pollution for human.Nitrogen and phosphorus pollution is the main cause for eutrophication in interior lakes,reservoirs and rivers,superabaundant phosphorus in water directly leadscyanobacteria bloom in lakes and red tide in near-coast waters.Dealing with the excess phosphorus in wastewater has been a hot area of the polluted water control,biological phosphorus removal is one of the best method for eutrophication with its low cost and non-secondary-pollution.In this study,nine bacteria strains were isolated from wastewater,The result of metachromatic granules staining showed that five strains of them containspolyphosphate particles,it meanst that they had the possibility of polyphosphate-accumulating,we named as AP01,AP03?AP05?AP06 and AP09 repectively.Among them,AP06 had the highest polyphosphate-accumulating rate,which got to84.8%,while the rest of the 5 strains were from 36.4%to 52.3%.The process optimization of polyphosphate-accumulating of AP06 was studied.By study on the effect of pH,temperature,the results of P resource and inoculumconcentration suggested that pH 7.0,30?,7%,K₂HPO₄ as the P resource and 7%of inoculum concentration was the best condition respectively.The most optimization condition of AP06 for polyphosphate-accumulating were pH 7.0,30?,7%,K₃PO₄ as the P resource and 7%of inoculum concentration,the highest efficiency got to 86.1%.The polyphosphate removal rate of AP06 was 68.5%in natural on no sterilized synthetic wastewater.And could get to 66.4%in sterilized synthetic wastewater.The phosphorus removal rate got to 35.8%in phosphorus mine wastewater.The physiological and biochemical characters test were done,all of them were positive in V-P test,methyl test,indole test and oxidase test.Analysing the 16SrDNA of AP06,the evolutionary tree of AP06 was constructed by Aeromonas sobria.from NCBI database.Their homologue got to 98%.