Study On The Method Of Antibiotic Degradation System In The Manure Of Livestock And Poultry Farming

To study the impact of intensive livestock farming on antibiotic pollution in the environment,and address the problems of large residues of veterinary antibiotics in livestock and poultry manure,low natural degradation rate,and difficulty to be removed by single physical,chemical and biological technologies.In this paper,bio-optical coupling degradation system was synthesized to study the performance and mechanism of its degradation of amoxicillin antibiotics in livestock and poultry manure.The main research contents are as follows:1.Screening of amoxicillin-degrading bacteria and optimization of fermentation conditions.Through traditional microbial isolation,enrichment screening and quantitative determination by HPLC-MS/MS,a bacterial strain named "AMX-1"was screened from the pig feces.The strain was identified as Bacillus by Gram staining and 16s rDNA sequencing.The degradation characteristics of the strain were studied by the response surface optimization method,and it was found that the fermentation time,temperature,initial pH value,shaking speed and inoculation amount had significant effect on fermentation culture of the strain.The results showed that the best combination was when the pH was 6.9,the fermentation time was 52 h,and the inoculation amount was 2%,resulting in an absorbance value(OD600)of 2.94,which was close to the expected value.2.Effects of exogenous antibiotics and degrading bacteria on microbial community structure and physicochemical properties of livestock and poultry manure composting.Addition of exogenous bacteria could improve the degradation rate of amoxicillin in the process of high temperature aerobic composting of pig manure.Addition of amoxicillin antibiotics could reduce the degree of maturity of pig manure compost,while the exogenous degradation bacteria could not only increase the heating rate and prolong the duration of high temperature of composting,but also increase the high temperature value,reduce the initial and final C/N ratios(T),and promote the further decay reaction in the compost.In the process of aerobic high temperature fermentation,the dominant microbial communities in the high temperature stage of composting were Firmicutes Bacteria unclassified(unclassified bacteria)Proteobacteria,Bacterioedetes,Acinobacteria,Candiastus Sacchairbaceria,and Chlamydiae.The genera with the highest level were Lactobacillus,Weissella,Klebsiella,Klebsiella,Enterococcus,Empedobacter,Leuconostoc,Pediococcus,and other genera.Streptomyces had strong high temperature tolerance,and thus had a clear advantage when exogenous degrading bacteria were added.Four types of beneficial bacteria were detected in the compost,which were Lactobacillus,Faecalibacterium,psychrobacter,and Brevibacillus.Four types of harmful bacteria were Bacteroides,Streptococcus,Corynebacterium and Staphylococcus.The removal efficiency of harmful bacteria in the antibiotic group was significantly lower than that in the exogenous bacteria group,and the relative abundance of beneficial bacteria was the highest in the exogenous bacteria group.3.Research and development of photodegradation equipment for antibiotics in livestock and poultry manure and optimization of parameters.An STM32 based rapid UV photodegradation system was developed for antibiotics degradation in composting.The system used 32W ultraviolet LED mercury lights as the antibiotic degradation light sources.The experiment was conducted to compare the amoxicillin degradation rates between LED and mercury light sources.The results showed that the degradation process of amoxicillin followed the first-order kinetic equation.The kinetic constants of amoxicillin degradation were determined to be-0.0199/min and-0.0019/min for LED and mercury lights,respectively.In other words,the degradation rate of amoxicillin by the LED light was faster than the mercury light.The response surface analysis was carried out to optimize the reaction conditions of the antibiotic photodegradation device,and the model accuracy was verified.Through the analysis of variance,the order of significant effect on the degradation of antibiotics by the operational parameter was as follows:time>radiation value>temperature.The optimal operation condition was determined as follows:radiation value of 2000 mw/cm2,time of 48 h,and temperature of 30?.Under this condition,the verification test of antibiotics degradation showed that the residue of amoxicillin was 0.28 mg/L,which was close to the expected value.4.Degradation of antibiotics in livestock and poultry manure by coupling microorganism and photo irradiation methods.The best combination of UV irradiation time and bacterial degradation is UV:18 h AMX:30 h.The amoxicillin antibiotics in the reactor(composter)was scanned near the 4000-400/cm by a Fourier transform infrared spectrometer.The O-H vibration in COOH disappeared near 3183.65/cm,and the absorption peak vibration of ?-lactam ring disappeared at 3083.02/cm and near 1477.71/cm,indicating that the coupled degradation system had an effect on the degradation of ?-lactam ring.However,an additional absorption vibration peak of chemical bond near 1382.81/cm appeared.As the reaction approached the end,the peak at 1382.81/cm disappeared and amoxicillin was degraded completely.The effects of different factors of the coupled system on the degradation of amoxicillin were studied.The results showed that the degradation rate of amoxicillin was close to 100%for pH 9 and temperature 30?.When the initial concentration of amoxicillin increased from 10 mg/L to 50 mg/L,the degradation rate decreased from 0.3067/h to 0.0612/h.5.The telligent monitoring system for antibiotic degradation for livestock and poultry manure.The design of the intelligent monitoring system for antibiotic degradation included the overall structure of the monitoring system and the sensor specifications,and hardware functions,as well as sensor selection for antibiotic residue degradation in livestock and poultry manure,the data acquisition module of RS-485 bus and the gateway from RS-485 to GPRS.Also developed was the software for the intelligent monitoring system for antibiotic degradation in livestock and poultry manure.The software systematically integrate models and algorithms developed in the previous chapters,including sensor data communication protocols,the software design of data acquisition module and gateway module,preprocessing of environmental data,multi-source data fusion,suitability assessment of environmental conditions,and the software design of server and mobile phone client.Finally,system application with user interfaces were demonstrated.The system achieved the functions of data collection,transmission,information processing and intelligent decision-making for antibiotic degradation of livestock and poultry manure.