The Application Of Bioaugmentaion In Fosfomycin Pharmaceutical Wastewater Treatment

Fosfomycin(FOM)is a broad-spectrum antibiotic which has been widely used in clinic.It has bactericidal activity against various gram-positive and distinct gram-negative bacteria by irreversibly blocking bacterial cell wall synthesis.A large amout of wastewater was produced in the manufacturing of FOM.It will be heavy threaten to human health and ecological environment if the FOM pharmautical wastewater is discharged into river without treatment.As one of the FOM pharmaceutical wastewater treatment technologies,biological treatment was preferred because of the economical operation fee.However,the conventional biological wastewater treatment was inhibited because of antibiotic components in wastewater,which effluent can’t satisfy the emission standard.So how to improve the efficiency become a burning questionand has the urgent practical significance.Fosfomycin(FOM)is a broad-spectrum antibiotic which has been widely used in clinic.It has bactericidal activity against various gram-positive and distinct gram-negative bacteria by irreversibly blocking bacterial cell wall synthesis.A large amout of wastewater was produced in the manufacturing of FOM.It will be heavy threaten to human health and ecological environment if the FOM pharmautical wastewater is discharged into river without treatment.As one of the FOM pharmaceutical wastewater treatment technologies,biological treatment was preferred because of the economical operation fee.However,the conventional biological wastewater treatment was inhibited because of antibiotic components in wastewater,which effluent can’t satisfy the emission standard.So how to improve the efficiency become a burning questionand has the urgent practical significance.In this study,the FOM pharmaceutical wastewater was treated by bioaugmentation.The 6 fosfomycin-degrading strains which isolated and purified from aerobic reactor of pharmaceutical wastewater treatment plant,were remixed.The growth conditions were optimized.The FOM pharmaceutical wastewater was treated bioaugmented with suspended high efficient FOM degrading bacteria and immobilization with materials.Further,the quantities of the high efficient FOM degrading bacteria were analyzed by Q-PCR.To get the optimum remixed ratio,the method of gradual expansion of the difference of microbial classification was applied.The six high efficient fosfomycin degrading bacteria were remixed in two steps.The optimal remixed ratio of N1:N2:N3:P1:P2:P3 was 1:1:1:1:1:1:1 when the inoculated ratio was 10%(V/V),with FOM concentration of 30.00 mg/L,temperature of 25℃,shaking speed of 120 r/min.The highest FOM removal efficiency was 86.06%with optimum remixed ratio after operated for 24 hr.To compare the efficiency of pharmaceutical wastewater treatment before and after bio-augmentation of high efficiency FOM degrading bacteria,the Cyclic Activated Sludge System(CASS)was operated.When the influent FOM concentration was 10.00 ± 0.20 mg/L,the mixed sludge Suspended Solids(MLSS)Was 3100.00 mg/L and the hydraulic Retention Time(HRT)was 6 d,the FOM removal efficiency was lower than 12.00%without inoculation of high efficiency FOM degrading bacteria.When the CASS reactor was inoculated with high efficiency FOM degrading bacteria at the ratio of 50%,the FOM removal efficiency was over 80.00%after 10 operation cycles,when the influent FOM concentration was 23.60-38.00 mg/L,the MLSS Was 2312.00 mg/L and the hydraulic Retention Time(HRT)was 6 d.When the reactor was inoculated with FOM high efficiency bacteria,the relative abundance of N1,N2,N3 changed from 78.53 copy/ugDNA,250.66 copy/ugDNA,108.68 copy/ugDNA to 1.92×104 copy/ugDNA,293.78 copy/ugDNA,1.21×104 copy/ugDNA.In steady state,the relative abundance of N1,N2,N3 was 123.65 copy/ugDNA,469.68 copy/ugDNA,181.19 copy/ugDNA.That may be the reson of higher FOM degradation efficiency of the system inoculated with FOM high degrading bacteria.To compare the effect of different materials on immobilization of FOM high efficiency degrading bacteria,the PE and PU-GEL materials were filled into CASS reactor separately.When the COD was 2500.00-4700.00 mg/L,HRT was 6 d,the COD removal efficiency of the reactor filled with PE was stabilized at 91.00%,effluent COD was lower than 300.00 mg/L.The influent organ phosphorus was 34.5～48.1 mg/L,the effluent organic phosphorus was 0.80～1.60 mg/L,the removal efficiency of organic phosphorus was 87.50%～91.90%%.The influent FOM was 22.70～39.70 mg/L,the effluent FOM was lower than 4.70 mg/L,the removal efficiency of fosfomycin was 89.90%～94.70%.When the COD was 2500.00-4700.00 mg/L,HRT was 6 d,the COD removal efficiency of the reactor filled with PU-GEL was stabilized at 93.10%,effluent COD was lower than 229.00 mg/L.The influent organ phosphorus was 36.70～67.70 mg/L,the effluent organic phosphorus was lower than 4.40 mg/L,the removal efficiency of organic phosphorus was 91.10%～95.20%.The influent FOM was 21.90～39.20 mg/L,the effluent FOM was than 0.80-1.60 mg/L,the removal efficiency of FOM was higher than 95.00%.At stable state,the relative abundance of N1,N2,N3 were 123.40～276.50 copy/ugDNA,118.80～549.70 copy/ugDNA,157.30～587.70 copy/ugDNA and 112.90～970.20 copy/ugDNA in reactor filled with PE and 112.90～970.20 copy/ugDNA,219.10～981.70 copy/ugDNA,404.70～2035.30 copy/ugDNA in reactor filled with PU-GEL.The effect of immobilization filled with PU-GEL was better than PE.