Isolation,Screening,Identification And Characterization Of Anaerobe Resistant To Low Phosphorus

In recent years,the total amount of sewage discharge has been increasing with the development of industry.The phosphorus deficiency was always observed in sewage and results in the imbalance of nutrient elements in water.It led the impossiblity to meet the optimal nutrient ratio of carbon,nitrogen and phosphorus required for microbial growth.This study based on the water quality characteristics of low phosphorus special wastewater from a brewery in Benxi.It obtained anaerobic activated sludge from the wastewater treatment process of the brewery and inoculated it into the UASB reactor in the laboratory,artificially simulated low phosphorus beer wastewater.Then it cultivated and domesticated the sludge until the UASB system ran stably.The aim of this study was:?1?to analyze the microflora structure in the syste;?2?to isolate and purify low-phosphorus anaerobe;?3?to analyze physiological and biochemical characteristics and 16S r DNA identification;?4?to analyze the growth characteristics of bacterial strain and degradation characteristics of low-phosphorus simulated beer wastewater.And to investigate the removal effects of single bacterial strain and compound bacteria on COD,NH₄⁺-N and TP.It provides efficient bacterial strain for biological treatment of low-phosphorus special wastewater.Illumina Mi Seq sequencing was used to investigate the microbial community structure of the low-phosphorus anaerobic activated sludge in stable UASB reactor.The results showed that the dominant bacterial genera were Chlorobium,Longilinea,Methanothrix and Levilinea,while the dominant archaea genera were Methanothrix and Methanobacterium.Compared with other common anaerobic activated sludge,the relative abundance of sulfate-reducing bacteria in the anaerobic activated sludge was thus higher.Sulfate-reducing bacteria were the dominant bacteria in the phosphorus deficiency reactor.The microorganisms in low-phosphorus anaerobic sludge in stable UASB reactor were separated and screened.LP1,LP2,LP4,LP5,LP6,LP7,LP8,LP9 and LP10 were isolated and purified.Physiological and biochemical identification of 9 strains of anaerobe with low-phosphorus tolerance were carried out.After 16S r DNA sequencing analysis,BLAST homology comparison was compared to obtain its corresponding bacteria genus and corresponding registration number:strains LP1 and LP6 were Cupriavidus sp;strain LP2 was Brevibacterium sp;strains LP4,LP5 and LP7 were Sphingomonas sp;strains LP8 and LP10were Acinetobacter sp;strain LP9 was Massilia sp.The corresponding login Numbers are MG674650.1,MH298691.1,CP035765.1,MH144243.1 and MK182878.1.This study analyzed the growth characteristics and degradation capacity of 5 strains of low phosphorus tolerant anaerobic bacteria?LP1,LP2,LP4,LP8 and LP9?.The growth periods of LP1,LP2,LP4,LP8 and LP9 were 21d,72h,84h,42h and 34h,respectively.The highest removal rates of COD were 53.86%,54.11%,37.57%,73.18%and 74.87%,respectively.Under low-phosphorus anaerobic conditions,LP4 strain led to the rise of the concentration of NH₄⁺-N in simulated wastewater,and LP9 strain had a certain removal effect on NH₄⁺-N.Strains LP2 and LP8 led to the rise of the concentration of TP.Compare the purification of 5 strains of anaerobic bacteria resistant to low phosphorus and its per amount of mixed bacteria growth rule and COD degradation ability.It was determined that the 5strains had the influence of ecological factors and the relationship of competitions,symbioses,intergrowthes and antagonisms.It provided the preliminary basis for the next compounding experiments.