Fluoroquinolone antibiotic degrading bacterium and tail water treatment method thereof

Abstract

The invention relates to the technical field of environment-friendly water treatment, in particular to a fluoroquinolone antibiotic degrading bacterium and a tail water treatment method thereof, the microorganism is classified and named as the antibiotic degrading bacterium and is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the preservation number is CGMCC NO.32797; and adding thalli of the antibiotic degrading bacteria or cultures of the thalli into the water body containing fluoroquinolone antibiotic residues with different concentrations, and carrying out co-culture. The method can effectively reduce residual fluoroquinolone antibiotics and organophosphorus in effluent of a sewage treatment plant and wastewater of a livestock farm, changes water quality and water environment by combining with submerged plants, increases the richness and diversity of water microbial species, and provides an efficient and environment-friendly new way for antibiotic pollution treatment of water.

Description

Technical Field

[0001] The invention relates to the technical field of environmental protection water treatment, in particular to fluoroquinolone antibiotic degrading bacteria and a tail water treatment method thereof. Background Art

[0002] In the context of rapid economic development and increasingly frequent human activities in modern society, the problem of antibiotic residue pollution in water bodies has become a focus of global attention, which seriously threatens the ecological balance and human life and health safety. Antibiotic residues in water bodies can destroy the balance of the ecosystem, promote the proliferation and evolution of resistance genes, and threaten public health. In addition, it affects water quality safety and affects the food chain through bioaccumulation, posing a potential risk to human and animal health. These problems make antibiotic residues an important environmental and health challenge that needs to be urgently addressed. Among them, fluoroquinolone antibiotics have a broad antibacterial spectrum, strong activity and good tissue penetration. They are widely used in the treatment of various infections, but their residues in the environment can easily induce microbial resistance, making infection treatment more difficult and threatening human health. At the same time, their residues pollute the water and soil ecology, destroy the balance of microbial communities, and affect the growth and reproduction of plants and animals. In view of this serious hazard and its far-reaching impact on the ecology and medical system, it is urgent to solve it.

[0003] At present, the treatment methods for antibiotic residues in water bodies mainly include three categories: physical adsorption, chemical oxidation and biological treatment. Although physical adsorption methods such as activated carbon adsorption are simple to operate, their adsorption capacity is limited and the adsorbent is difficult to regenerate, making it difficult to achieve large-scale treatment. Chemical oxidation methods such as advanced oxidation technologies such as Fenton oxidation can degrade antibiotics to a certain extent, but this method often requires a large amount of chemical agents, which is costly and may produce toxic and harmful intermediates, causing secondary pollution and affecting the subsequent utilization value of the water body.

[0004] As a treatment method with great potential, biological treatment utilizes the metabolic function of microorganisms to decompose and remove antibiotics from water. This method has attracted widespread attention due to its advantages such as good environmental compatibility and relatively low treatment cost. Among the many microorganisms involved in biological treatment, antibiotic-degrading bacteria are a key part. Antibiotic-degrading bacteria have unique physiological and biochemical characteristics and metabolic mechanisms, which enable them to survive and function in harsh environments containing antibiotics. They can participate in the degradation and transformation of antibiotics through various pathways such as biodegradation, biosorption, synergistic metabolism, and niche competition, providing an efficient, environmentally friendly and innovative solution for removing antibiotic residues from water, and showing broad application prospects in the field of water antibiotic pollution control. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a fluoroquinolone antibiotic-degrading bacterium to solve the above problem.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a fluoroquinolone antibiotic-degrading bacterium, the microbial classification is named antibiotic-degrading bacteria ( Pseudomonas alcaligenes ), the strain was isolated from the biofilm attached to the submerged plant Ceratophyllum dactylum, and the bacteria were identified by 16S sequencing and morphological identification as belonging to the genus Pseudomonas ( Pseudomonas ), deposited in the General Microbiology Center of China Microorganism Culture Collection Administration (CGMCC), located at Beichen West Road, Chaoyang District, Beijing, with the deposit number: CGMCC NO.32797 and the deposit date: November 25, 2024. As a further embodiment of the present invention, the fluoroquinolone antibiotic-degrading bacteria are used to remove fluoroquinolone antibiotic residues in tail water and improve water quality.

[0007] As a further embodiment of the present invention, the antibiotic degrading bacteria include but are not limited to a composite antibiotic combination of fluoroquinolones (NOR and OFL).

[0008] A method for treating tail water of fluoroquinolone antibiotic-degrading bacteria comprises the steps of adding the bacterial bodies or cultures of the antibiotic-degrading bacteria into water bodies containing fluoroquinolone antibiotic residues of different concentrations and performing co-cultivation.

[0009] As a further embodiment of the present invention, the culture of the antibiotic-degrading bacteria is a liquid culture.

[0010] As a further embodiment of the present invention, the content of the antibiotic-degrading bacteria added to the water body is not less than 10 3 cfu / mL.

[0011] As a further embodiment of the present invention, antibiotic-degrading bacteria are applied to water bodies containing fluoroquinolone antibiotic residues to remove or reduce the content of fluoroquinolone antibiotics in tail water bodies, change water quality and water environment, and increase the richness and diversity of water microbial species.

[0012] As a further solution of the present invention, the drug is delivered directly or after being combined with a carrier.

[0013] Since the present invention adopts the above technical solution, the present invention has the following advantages and positive effects: 1. The present invention uses the biofilm attached to the surface of submerged plants in natural wetlands as the source of bacterial strain isolation, and through screening and cultivation, enriches to obtain strains with stable environmental antibiotic degradation effects. The strains are derived from natural wetlands and can ensure the safety of water ecology and aquatic organisms; 2. The strain can effectively remove residual fluoroquinolone antibiotics and organophosphorus substances in tail water, reduce the content of fluoroquinolone antibiotics in water, purify water quality and improve the water environment, and increase the richness and diversity of water microbial species. This technology has the advantages of low cost, simple operation and high safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The changes in antibiotic removal rates in water bodies with the addition of fluoroquinolone antibiotic-degrading bacteria; Figure 2 This is the growth curve of the fluoroquinolone antibiotic-degrading strain. DETAILED DESCRIPTION Example

[0015] The present invention discloses an application of fluoroquinolone antibiotic-degrading bacteria in removing fluoroquinolone antibiotic residues in tail water. The fluoroquinolone antibiotic-degrading bacteria are obtained by screening and separating the biofilm attached to the submerged plant hornwort, and the bacteria are applied to remove residual antibiotics in the effluent of sewage treatment plants and wastewater from aquaculture farms.

[0016] Fluoroquinolone antibiotics (NOR and OFL) were added to the solid LB medium in a liquid state at a ratio of 1:100. After the medium solidified, 100 μL of each gradient dilution was taken and evenly spread on each resistance plate, and each plate was repeated 3 times. The coated plate was placed in a constant temperature incubator at 26°C and incubated inverted for 24 hours. After the colony growth was formed, the colonies with significant differences in colony morphology, size, color and other characteristics were screened by naked eye observation, and they were picked to the resistance plate consistent with their growth conditions. The partitioning and streaking method was used many times to implement the expansion culture operation until the single colony was isolated and purified, and then the 16S rDNA strain identification was carried out. At the same time, the single colony was stored in a refrigerator at -80°C using the glycerol preservation method.

[0017] Take out the frozen antibiotic degradation strain glycerol tube from the -80℃ refrigerator, thaw at room temperature, and then streak culture on the corresponding resistance plate (culture temperature is 26℃, duration is 24 hours). Pick single colonies and inoculate them into conical flasks containing 200 mL LB liquid culture medium. Shake and culture at 300 rpm at 37℃ until the optical density (OD) value reaches 1. In the clean bench, the culture medium of each strain was divided into 50 mL centrifuge tubes, centrifuged at 10000 r / min for 10 minutes, and the supernatant was removed. After that, sterile water was added several times and the centrifugation operation was repeated to wash the strain, and finally the precipitated strain was obtained.

[0018] In this embodiment, five treatment groups are set up, namely: a group without antibiotics and antibiotic-degrading bacteria (NKNB), a group without antibiotics but with antibiotic-degrading bacteria (NKB), a group containing 0.05 mg / L fluoroquinolone antibiotics and antibiotic-degrading bacteria (LB), a group containing 0.5 mg / L fluoroquinolone antibiotics and antibiotic-degrading bacteria (MB), and a group containing 1.0 mg / L fluoroquinolone antibiotics and antibiotic-degrading bacteria (HB).

[0019] In this example, the concentration of the fluoroquinolone antibiotic-degrading strain in each treatment group reached 10³ CFU / mL.

[0020] In this embodiment, Figure 1 As shown, the treatment period is 16 days, and fluoroquinolone antibiotics are added to the water of the treatment group to a set concentration every four days.

[0021] In this embodiment, Figure 2 As shown in the figure, by measuring the content of fluoroquinolone antibiotics in each group, it was found that in the early stage of the experiment, the removal rate of fluoroquinolone antibiotics in each group of water bodies exceeded 80%, which was significantly higher than that of the group without adding antibiotic degrading bacteria. This shows that the added fluoroquinolone antibiotic degrading strains have the ability to significantly degrade fluoroquinolone antibiotics and can effectively improve the removal efficiency of fluoroquinolone antibiotics in water bodies. In the last experimental cycle, the experimental system still had a good removal effect on fluoroquinolone antibiotics, and the treatment groups with added antibiotic degrading bacteria had a high removal rate for fluoroquinolone antibiotics. These results also provide an important basis for further understanding the mechanism of action of antibiotic degrading strains in the control of antibiotic pollution in water bodies.

[0022] Although specific embodiments of the present invention are described above, those skilled in the art should understand that these are merely examples and that various changes or modifications may be made to the embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is limited only by the appended claims.

Claims

1. A fluoroquinolone antibiotic-degrading bacterium, characterized in that: The microorganism is classified and named as antibiotic-degrading bacteria and is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration with the deposit number: CGMCC NO.32797.

2. The fluoroquinolone antibiotic-degrading bacteria according to claim 1, characterized in that: The fluoroquinolone antibiotics degrading bacteria are used to remove fluoroquinolone antibiotics residues in tail water and improve water quality.

3. A fluoroquinolone antibiotic-degrading bacterium according to claim 2, characterized in that: The antibiotic degrading bacteria include, but are not limited to, complex antibiotic combinations of fluoroquinolones.

4. A method for treating tail water of fluoroquinolone antibiotic-degrading bacteria according to any one of claims 1 to 3, characterized in that: The antibiotic-degrading bacteria or their culture is added into water containing fluoroquinolone antibiotic residues of different concentrations and co-cultured.

5. The method for treating tail water of fluoroquinolone antibiotic-degrading bacteria according to claim 4, characterized in that: The culture of the antibiotic degrading bacteria is a liquid culture.

6. The method for treating tail water of fluoroquinolone antibiotic-degrading bacteria according to claim 4, characterized in that: The content of the antibiotic-degrading bacteria added to the water body is not less than 10 3 cfu / mL.

7. The method for treating tail water of fluoroquinolone antibiotics-degrading bacteria according to claim 4, characterized in that: Antibiotic-degrading bacteria are applied to water bodies containing fluoroquinolone antibiotic residues to remove or reduce the content of fluoroquinolone antibiotics in tail water bodies, change water quality and water environment, and increase the richness and diversity of water microbial species.

8. The method for treating tail water of fluoroquinolone antibiotics-degrading bacteria according to claim 4, characterized in that: Directly delivered or delivered after combining with a carrier.

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