Arthrobacter uretogenes and application of arthrobacter uretogenes in degradation of N-methyl pyrrolidone and inorganic nitrogen

Abstract

The invention relates to the technical field of microorganisms, and discloses arthrobacter uretogenes and application of the arthrobacter uretogenes in degradation of N-methyl pyrrolidone and inorganic nitrogen. The arthrobacter uretogenes disclosed by the invention can efficiently remove pollutants such as N-methyl pyrrolidone and inorganic nitrogen within a short time, has the advantages of quick response and high treatment efficiency, can be widely applied to industrial wastewater and aquaculture wastewater or treatment of polluted soil, and has important significance in promoting environmental protection and industrial sustainable development.

Description

Technical Field

[0001] This invention relates to the field of microbial technology, specifically to a strain of Arthrobacter ureagenesis and its application in the degradation of N-methylpyrrolidone and inorganic nitrogen. Background Technology

[0002] N-methylpyrrolidone (NMP) is a pale yellow, transparent liquid, belonging to heterocyclic compounds, with a slight ammonia odor. Due to its good water miscibility, low volatility, and non-corrosiveness, NMP is widely used in processes such as aromatic hydrocarbon extraction, acetylene concentration, and syngas desulfurization. NMP is also an important industrial solvent in the production of pesticides, engineering plastics, and coatings.

[0003] However, NMP has a stable structure, poor biodegradability, and is easily transferred in soil and groundwater. It is irritating to organs such as the eyes, skin, and respiratory tract, and also exhibits biotoxicity and teratogenicity. Therefore, restoring the aquatic ecosystem contaminated by NMP has become one of the important issues in the field of environmental governance.

[0004] Currently, methods for treating NMP-containing wastewater include advanced oxidation processes (AOF), membrane separation, and biological treatment. AOF utilizes strong oxidants to oxidize and decompose NMP, but this method consumes significant amounts of energy and chemical reagents, resulting in high treatment costs and potential secondary pollution. Membrane separation uses specific membrane materials to separate NMP from the wastewater; this method is also costly, and the membrane materials can become fouled, requiring regular replacement. Biological treatment utilizes microorganisms to degrade NMP; this method offers numerous advantages, including being economical, efficient, and causing minimal secondary pollution, achieving harmless treatment and is the most widely used wastewater treatment technology.

[0005] In the field of biological treatment technology, several publications have disclosed strains capable of degrading NMP. For example, CN106591169A discloses a Bacillus NMP-2 strain that degrades N-methylpyrrolidone and its application. This strain, a Bacillus, achieved a 98% degradation rate of 500 mg / L NMP in a laboratory shake-flask environment after 72 hours. CN109913387A discloses an Enterobacterium that degrades N-methylpyrrolidone and its application in wastewater treatment. The seed culture of this strain was added at a volume ratio of 5% to an inorganic salt liquid culture medium containing 2800-3100 mg / L NMP, resulting in complete NMP degradation within 55 hours. CN112574916B discloses an N-methylpyrrolidone-degrading bacterium and its application in wastewater treatment. The NMP-degrading strain is Bacillus pumilus. The seed culture of this strain was added at a volume ratio of 5% to an inorganic salt liquid culture medium containing 12.8 ± 0.8 mM NMP. In inorganic salt liquid medium, NMP was completely degraded within 23 hours. Although the aforementioned strains could degrade N-methylpyrrolidone, the degradation concentration was low (500-3000 mg / L). -1 In other words, the degradation efficiency is not high; and the degradation cycle is generally long, lasting 23-72 hours. The low efficiency makes it difficult to achieve widespread industrial application.

[0006] Wastewater containing NMP often has a complex composition and contains a large number of inorganic salt ions. In addition, the toxicity and recalcitrant nature of NMP make it difficult for ordinary biodegradation to be effective. Therefore, it is essential to find a strain that can efficiently isolate and degrade N-methylpyrrolidone. Summary of the Invention

[0007] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a strain of Arthrobacter ureagenesis and its application in the degradation of N-methylpyrrolidone and inorganic nitrogen.

[0008] To achieve the above and other related objectives, the present invention is obtained through the following technical solution.

[0009] The first aspect of this invention protects a strain of Ureaplasma urealyticum ( Paenarthrobacter ureafaciens The strain WL-NMP191, with accession number CGMCC No. 35551.

[0010] In some embodiments, the 16S rDNA sequence of the strain is shown in SEQ ID No. 1.

[0011] A second aspect of the present invention protects a culture obtained by culturing the strain described above.

[0012] A third aspect of the present invention protects a microbial preparation comprising the strains or cultures described above.

[0013] The fourth aspect of this invention protects the use of the strains, cultures, or microbial preparations described above in at least one of the following:

[0014] A1) Degradation of inorganic nitrogen;

[0015] A2) Prepare products that degrade inorganic nitrogen;

[0016] A3) Degradation of N-methylpyrrolidone;

[0017] A4) Prepare products that degrade N-methylpyrrolidone.

[0018] In some embodiments, the operating temperature of the strain, culture, or microbial preparation is 15–35°C.

[0019] In some embodiments, the inorganic nitrogen or N-methylpyrrolidone is present in the environment, which includes one or more of water bodies, soil, and aquatic sediments.

[0020] In some embodiments, the inorganic nitrogen includes one or more of ammonia nitrogen, nitrate, and nitrite.

[0021] A fifth aspect of the present invention protects a method for biodegrading inorganic nitrogen and / or N-methylpyrrolidone, comprising: treating the object to be treated with the strains, cultures, or microbial preparations described above.

[0022] In some implementations, the object to be treated includes one or more of water, soil, and aquatic sediments.

[0023] In some embodiments, the processing temperature is 15–35°C.

[0024] In some embodiments, the treatment also includes the addition of ammonium sulfate.

[0025] In some embodiments, the mass ratio of the ammonium sulfate to the N-methylpyrrolidone in the object to be treated is 1:(1-10).

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1) The Ureaplasma urealyticum of the present invention Paenarthrobacter ureafaciens WL-NMP191 exhibits remarkable environmental adaptability and tolerance, enabling it to efficiently metabolize and grow in the presence of ammonia nitrogen, nitrate, and N-methylpyrrolidone.

[0028] 2) The Ureaplasma urealyticum of the present invention Paenarthrobacter ureafaciensWL-NMP191 has highly efficient nitrification and denitrification capabilities, with a reduction rate of over 99.68% for ammonia nitrogen and nitrate within 24 hours. Therefore, it is beneficial for water body restoration and water quality improvement, and has significant application value.

[0029] 3) The Ureaplasma urealyticum of the present invention Paenarthrobacter ureafaciens WL-NMP191 has a highly efficient ability to degrade N-methylpyrrolidone, and can completely degrade 500 mg / L NMP within 48 hours. Therefore, it has important application value in the treatment of industrial wastewater and the reduction of environmental pollution.

[0030] 4) The *Arthrobacter ureagenes* of this invention can achieve highly efficient removal of pollutants within a short time (24 to 48 hours), exhibiting a rapid response advantage and improving overall treatment efficiency. Therefore, it has promising application prospects and is of great significance for promoting environmental protection and sustainable industrial development. Attached Figure Description

[0031] Figure 1 This is a morphological observation diagram of Ureaplasma urealyticum in Example 1 of the present invention.

[0032] Figure 2 This is a diagram showing the results of N-methylpyrrolidone degradation by Arthrobacter ureagenesis in Example 3 of the present invention. Detailed Implementation

[0033] The term "culture" refers to a liquid or solid product (all substances within the culture vessel are fermentation products) that has grown a microbial community after artificial inoculation and cultivation. It is a product obtained by growing and / or amplifying microorganisms; it can be a biologically pure culture of microorganisms, or it can contain a certain amount of culture medium, metabolites, and / or other components produced during the cultivation process. The term "culture" also includes passaged cultures obtained by subculturing microorganisms; these can be cultures of a single generation or mixtures of several generations.

[0034] The first aspect of this invention protects a strain of Ureaplasma urealyticum ( Paenarthrobacter ureafaciens The strain WL-NMP191, with accession number CGMCC No. 35551.

[0035] Ureaplasma gondii (Paenarthrobacter ureafaciens) The WL-NMP191 strain was deposited on August 8, 2025, at the China General Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing, with accession number CGMCC No. 35551. It was isolated from wastewater sludge.

[0036] The morphological characteristics of the Paenarthrobacter ureafaciens strain WL-NMP191 described in this application are: yellow, moist surface, and regular shape. Its 16S rDNA shows 99.31% homology with the type strain Paenarthrobacter ureafaciens strain in GenBank.

[0037] In some embodiments, the 16S rDNA sequence of the strain is shown in SEQ ID No. 1.

[0038] A second aspect of the present invention protects a culture obtained by culturing the strain described above.

[0039] In some embodiments, the culture is a fermentation product or metabolite of the strain.

[0040] In some embodiments, the fermentation product comprises the strains described above or is obtained by culturing the strains described above in a culture medium. As an example, the culture medium may be a solid or liquid medium, including but not limited to MSM medium, LB medium, MS medium, PDA medium, Czapek's agar, and beef extract peptone medium. The culture temperature may be 15–35°C, 20–28°C, or 25°C, 28°C, or 30°C.

[0041] A third aspect of the present invention protects a microbial preparation comprising the strains or cultures described above.

[0042] In some embodiments, the dosage form of the microbial preparation may be a variety of dosage forms, such as liquid, emulsion, suspension, powder, granules, wettable powder or water-dispersible granules.

[0043] In some embodiments, the microbial agent further includes a carrier.

[0044] In some embodiments, the carrier includes a solid carrier or a liquid carrier. The solid carrier includes mineral materials, plant materials, and / or polymeric compounds; the mineral material may be at least one selected from clay, talc, maifanite, kaolin, montmorillonite, white carbon, zeolite, silica, and diatomaceous earth; the plant material may be at least one selected from corn flour, soybean flour, rice husk powder, and starch; the polymeric compound may be polyvinyl alcohol or / and polyethylene glycol. The liquid carrier may be an organic solvent, vegetable oil, mineral oil, or water; the organic solvent may be decane or / and dodecane.

[0045] In some embodiments, the microbial preparation may also contain surfactants (such as Tween 20, Tween 80, etc.), binders, stabilizers (such as antioxidants), pH adjusters, etc.

[0046] The fourth aspect of this invention protects the use of the strains, cultures, or microbial preparations described above in at least one of the following:

[0047] A1) Degradation of inorganic nitrogen;

[0048] A2) Prepare products that degrade inorganic nitrogen;

[0049] A3) Degradation of N-methylpyrrolidone;

[0050] A4) Prepare products that degrade N-methylpyrrolidone.

[0051] In some embodiments, the working temperature of the strain, culture, or microbial preparation is 15–35°C, or it can be 20–28°C, or it can be 25°C, 28°C, or 30°C.

[0052] In some embodiments, the inorganic nitrogen or N-methylpyrrolidone is present in the environment, which includes one or more of water bodies, soil, and aquatic sediments. The water body contains ammonia nitrogen, nitrates, or N-methylpyrrolidone.

[0053] In some embodiments, the inorganic nitrogen includes one or more of ammonia nitrogen, nitrate, and nitrite.

[0054] A fifth aspect of the present invention protects a method for biodegrading inorganic nitrogen and / or N-methylpyrrolidone, comprising: treating the object to be treated with the strains, cultures, or microbial preparations described above.

[0055] In some implementations, the object to be treated includes one or more of water, soil, and aquatic sediments.

[0056] In some embodiments, the processing temperature is 15–35°C.

[0057] In some embodiments, the treatment also includes the addition of ammonium sulfate. The mass ratio of the ammonium sulfate to N-methylpyrrolidone in the object to be treated can be 1:(1-10), 1:(1-5), 1:(7-8), 1:(5-10), or 1:1, 1:3, 1:5, 1:8, or 1:10. This application has found that the addition of ammonium sulfate can improve the degradation efficiency of NMP or inorganic nitrogen by strain WL-NMP191 and its cultures or inoculants.

[0058] The Ureaplasma urealyticum of this application Paenarthrobacter ureafaciensWhen WL-NMP191 and its culture or inoculum were inoculated into nitrifying medium, the ammonia nitrogen concentration decreased by 99.94% after 24 hours of treatment; when inoculated into aerobic denitrification medium, the nitrate concentration decreased by 99.68% after 24 hours of treatment; and when inoculated into water containing 500 mg / L N-methylpyrrolidone, the N-methylpyrrolidone in the water was almost completely degraded after 48 hours. In summary, the *Arthrobacter ureagenes* of this invention can achieve highly efficient removal of pollutants in a short time (24 to 48 hours), exhibiting a rapid response advantage and improving overall treatment efficiency. Therefore, it has good application prospects and is of great significance for promoting environmental protection and sustainable industrial development.

[0059] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0060] Before further describing specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terminology used in the embodiments of the present invention is for describing specific embodiments and not for limiting the scope of protection of the present invention; in the specification and claims of the present invention, unless otherwise expressly stated in the text, the singular forms "a", "an" and "this" include the plural forms.

[0061] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in this invention, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art. In addition to the specific methods, apparatus, and materials used in the embodiments, this invention may be implemented using any prior art methods, apparatus, and materials similar to or equivalent to those described in the embodiments of this invention, provided that one of those skilled in the art possesses the prior art and that this invention is described.

[0062] The culture medium formulations involved in the embodiments of this application are as follows:

[0063] The LB liquid medium formula is: 10 g / L tryptone, 5 g / L yeast extract, 10 g / L sodium chloride, 1 L water, pH 7.0-7.2, sterilized at 121℃ for 30 min. For solid medium, add 1.5-2% agar.

[0064] NMP-MSM medium composition: ammonium sulfate 2 g / L, magnesium sulfate 0.098 g / L, calcium chloride 0.0076 g / L, ferrous sulfate 0.001 g / L, disodium hydrogen phosphate 1.5 g / L, potassium dihydrogen phosphate 1.5 g / L, NMP 5000 mg / L, natural pH, calcium chloride needs to be dissolved by heating, and 2% agar is added when solid. All reagents are of analytical grade.

[0065] Example 1: Isolation and identification of Ureaplasma urealyticum

[0066] In this embodiment, Ureaplasma ureagenes was screened, isolated, and identified from sludge. The steps included:

[0067] 1.1 Isolation of strains

[0068] A 500 mL water sample was obtained from existing wastewater sludge containing 20.32 mg / L ammonia nitrogen and 1965.01 mg / L N-methylpyrrolidone using a sterile water sample collection bag. 1 mL of the sample was added to 100 mL of pre-sterilized LB liquid medium and placed in a constant temperature shaker at 28℃ and 200 r / min for enrichment culture for 3 days.

[0069] Take 1 mL of the enriched culture medium and dilute it in 9 mL of sterile pure water, mix well, and label it as #10-1 mixture; take 1 mL of #10-1 mixture and dilute it in 9 mL of sterile pure water, mix well, and label it as #10-2 mixture; continue diluting to #10-6 mixture. Starting from the lowest concentration #10-6, pipette 0.1 mL of each diluted bacterial solution onto an LB agar plate, spread it evenly with a disposable spreader, and label it. Invert the plate and incubate it at 28℃ to observe colony growth.

[0070] Single colonies with different morphologies and colors and good separation were selected and streaked multiple times on NMP-MSM agar plates. After more than five generations of purification, a strain capable of efficiently degrading NMP was finally obtained and named WL-NMP191. The morphological characteristics of this strain on LB agar were: yellow, moist surface, and regular shape, as shown in the image. Figure 1 As shown.

[0071] 1.2 Identification of strains

[0072] The purified strain WL-NMP191 was sent to Shanghai Saiheng Biotechnology Co., Ltd. for 16S rDNA sequencing. The obtained sequence was compared with the database of the National Center for Bioinformatics (NCBI) (https: / / blast.ncbi.nlm.nih.gov / Blast.cgi?PROGRAM=blastn&PAGE_TYPE=BlastSearch&LINK_LOC=blasthome) and it was found that the 16S rDNA sequence matched the type strain in GenBank. Paenarthrobacter ureafaciens The strain homology was 99.31%.

[0073] The 16S rDNA sequence of strain WL-NMP191 is shown below:

[0074]

[0075] Based on morphological analysis and 16S rDNA analysis, this strain was identified as *Arthrobacter ureagenes* WL-NMP191. The taxonomic name of this strain is *Arthrobacter ureagenes*. Paenarthrobacter ureafaciens WL-NMP191, with accession number CGMCC No.35551, was deposited on August 8, 2025, at the China General Microbiological Culture Collection Center, located at No.3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing.

[0076] Example 2: Study on the degradation of inorganic nitrogen by strain WL-NMP191

[0077] In Example 2, the strain WL-NMP191 obtained in Example 1 was subjected to nitrification and aerobic denitrification treatments to investigate its effectiveness in degrading inorganic nitrogen. This included the following:

[0078] 2.1 Nitrification performance

[0079] Nitrification medium: ammonium chloride 0.2 g / L, ferrous sulfate 0.02 g / L, dipotassium hydrogen phosphate 0.1 g / L, potassium dihydrogen phosphate 0.1 g / L, magnesium sulfate 0.1 g / L, glucose 1 g / L, pH 7 ± 0.2.

[0080] Single colonies of strain WL-NMP191 from Example 1 were inoculated into LB liquid medium and cultured for 3 days. Then, at an inoculation rate of 5% (v% / v%), they were inoculated into 150 mL of nitrification medium and cultured on a constant temperature shaker at 28°C and 150 rpm for 1 day. Ammonia nitrogen levels were measured every 6 hours. Three parallel groups were set up for each group (experimental group A1, experimental group A2, and experimental group A3), and one control group was set up. The measured data are shown in Table 1 below.

[0081] The ammonia nitrogen measurement method employed Nessler's reagent spectrophotometry. The procedure was as follows: 5 mL of culture product was taken from each time point and added to a 50 mL colorimetric tube. The solution was diluted to the mark, and 1.0 mL of potassium tartrate solution and 1.5 mL of Nessler's reagent were added. After standing for 10 minutes, the absorbance was measured at 420 nm. For details, please refer to the Nessler's reagent spectrophotometric method (A) in "Methods for Monitoring and Analysis of Water and Wastewater (Fourth Edition)".

[0082] The principle of Nessler's reagent spectrophotometry is as follows: mercuric iodide and potassium iodide in an alkaline solution react with ammonia to form a pale reddish-brown colloidal compound, which has strong absorption over a wide wavelength range.

[0083] Table 1. Test of ammonia nitrogen degradation performance of strain WL-NMP191

[0084]

[0085] Table 1 shows that strain WL-NMP191 has good nitrification performance. Experimental groups A1, A2, and A3 can all efficiently degrade ammonia nitrogen, reducing the average concentration of ammonia nitrogen from 51.43 mg / L to 0.03 mg / L in 24 hours. Overall, the ammonia nitrogen concentration was reduced by 99.94% across the three groups.

[0086] 2.2 Aerobic Denitrification Performance Test

[0087] Aerobic denitrification medium: sodium nitrate 0.6 g / L, potassium dihydrogen phosphate 0.2 g / L, dipotassium hydrogen phosphate 0.2 g / L, magnesium sulfate 0.1 g / L, ferrous sulfate 0.02 g / L, glucose 2 g / L, pH 7.0 ± 0.2.

[0088] A single colony of strain WL-NMP191 from Example 1 was inoculated into pre-sterilized LB liquid medium and cultured on a shaker at 200 rpm for 3 days to obtain a seed culture. 1 mL of the seed culture was added to 400 mL of pre-sterilized aerobic denitrification medium and cultured on a shaker at 200 rpm. Nitrate levels were measured every 6 hours. Three parallel groups (experimental group B1, experimental group B2, and experimental group B3) and one control group were set up for each group. The data are shown in Table 2 below.

[0089] The nitrate content was measured using the nitrate nitrogen ultraviolet spectrophotometric method. The procedure was as follows: 5 mL of culture product was taken from each time point and added to a 50 mL colorimetric tube. The solution was diluted to the mark, and 1.0 mL of hydrochloric acid solution and 0.1 mL of sulfamic acid solution were added. The absorbance was measured at 220 and 275 nm. For details, please refer to the nitrate nitrogen ultraviolet spectrophotometric method (B) in "Methods for Monitoring and Analysis of Water and Wastewater (Fourth Edition)".

[0090] The principle of the nitrate nitrogen ultraviolet spectrophotometric method (B) is to quantitatively determine nitrate nitrogen by utilizing the absorption of nitrate ions at a wavelength of 220 nm. Dissolved organic matter also absorbs at 220 nm, while nitrate ions do not absorb at 275 nm. Therefore, a second measurement is performed at 275 nm to correct for the nitrate nitrogen value.

[0091] Table 2. Nitrate degradation performance test of strain WL-NMP191

[0092]

[0093] Table 2 shows that strain WL-NMP191 exhibits highly efficient nitrate degradation under aerobic conditions, reducing the average nitrate concentration from 100.88 mg / L to 0.32 mg / L in 24 hours. Combined, the three groups indicate a 99.68% reduction in nitrate concentration.

[0094] Example 3: Study on the degradation of N-methylpyrrolidone by strain WL-NMP191

[0095] In Example 3, wastewater was treated with strain WL-NMP191 obtained in Example 1 to investigate its degradation effect on N-methylpyrrolidone. This included the following:

[0096] 3.1 Treatment with Ureaplasma ureagenesis WL-NMP191 for the degradation of N-methylpyrrolidone

[0097] 1) A single colony of strain WL-NMP191 from Example 1 was inoculated into LB liquid medium (sterile) containing 200 mg / L NMP, placed on a shaker, and cultured at 200 r / min and 28°C for 3 days to obtain seed culture.

[0098] 2) Add 500 mL of inorganic salt liquid culture medium containing 500 mg / L NMP and 2 g / L ammonium sulfate to a 1 L Erlenmeyer flask, sterilize at 121 °C for 30 min, and cool to room temperature for later use as simulated wastewater. The inorganic salt liquid culture medium containing 500 mg / L NMP and 2 g / L ammonium sulfate has the following components: ammonium sulfate 2 g / L, calcium chloride 0.0076 g / L, ferrous sulfate 0.001 g / L, disodium hydrogen phosphate 1.5 g / L and dipotassium hydrogen phosphate 1.5 g / L, NMP 500 mg / L, pH 7.0 ± 0.2.

[0099] 3) The seed culture from step 1) was inoculated into the simulated wastewater from step 2) at an inoculation rate of 5% (v% / v%) and cultured in a shaker at 28°C and 200 r / min. This group was designated as the biological experimental group.

[0100] The experimental group with NMP added but no ammonium sulfate was used as the biological control group. The inorganic salt culture medium without ammonium sulfate consisted of: NMP 500 mg / L, calcium chloride 0.0076 g / L, ferrous sulfate 0.001 g / L, disodium hydrogen phosphate 1.5 g / L, and dipotassium hydrogen phosphate 1.5 g / L, pH 7.0 ± 0.2.

[0101] Simulated wastewater without any bacterial strains was used as a non-biological control group.

[0102] Each group has three parallel groups.

[0103] 3.2 HPLC detection of NMP

[0104] In step 3.1, samples of 5 mL were taken at 0, 6, 12, 18, 24, 30, 36, 42, and 48 hours after culturing to monitor NMP in the simulated wastewater. NMP was detected using high-performance liquid chromatography (HPLC). Experimental data were calculated as averages of the three groups; a summary of the data can be found here. Figure 2 .

[0105] The HPLC detection conditions are shown in Table 3.

[0106] Table 3

[0107]

[0108] from Figure 2 It can be seen that in the presence of ammonium sulfate, strain WL-NMP191 exhibits better NMP degradation efficiency, essentially completely degrading NMP within 48 hours, with an NMP concentration of 0 mg / mL in the reaction system. The biological control group without ammonium sulfate only degraded a portion of the NMP; compared to 0 hours, approximately 20% of the NMP was degraded after 48 hours. In the non-biological control group without strain WL-NMP191, the NMP concentration remained essentially unchanged within 48 hours, indicating that NMP degradation was minimal. In the presence of ammonium sulfate, strain WL-NMP191 can utilize ammonium sulfate as a nitrogen source and NMP as a carbon source. In the biological control group without ammonium sulfate, NMP serves as both a carbon and nitrogen source, resulting in a significantly lower NMP degradation rate compared to the biological experimental group.

[0109] The above embodiments are for illustrating the implementation schemes disclosed in this invention and should not be construed as limiting the invention. Furthermore, various modifications listed herein, as well as variations in the methods and compositions of the invention, will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been specifically described in conjunction with various specific preferred embodiments, it should be understood that the invention should not be limited to these specific embodiments. In fact, various modifications as described above that are obvious to those skilled in the art to obtain the invention should be included within the scope of this invention.

Claims

1. A urea-producing Arthrobacter sp. ( Paenarthrobacter ureafaciens ) WL-NMP191 strain, having a preservation number of CGMCC No. 35551.​ 2. The strain of claim 1, wherein, The 16S rDNA sequence of the strain comprises the sequence shown in SEQ ID No.

1.

3. A culture, characterized in that, The culture is obtained by culturing the strain of claim 1 or 2.

4. A microbial preparation, characterized in that, The microbial preparation comprises the strain of claim 1 or 2 or the culture of claim 3.

5. Use of the strain of claim 1 or 2 or the culture of claim 3 or the microbial preparation of claim 4 in at least one of the following; A1) degrading inorganic nitrogen; A2) preparing a product for degrading inorganic nitrogen; A3) degrading N-methylpyrrolidone; A4) preparing a product for degrading N-methylpyrrolidone.

6. The use according to claim 5, characterized in that, The working temperature of the strain or the culture or the microbial preparation is 15-35℃; And / or, the inorganic nitrogen comprises one or more of ammonia nitrogen, nitrate and nitrite.

7. A method of biodegrading inorganic nitrogen and / or N-methylpyrrolidone comprising: The strain of claim 1 or 2 or the culture of claim 3 or the microbial preparation of claim 4 is used to treat a to-be-treated object.

8. The method of claim 7, wherein, The to-be-treated object comprises one or more of water, soil and water sediment; And / or, the temperature of the treatment is 15-35℃.

9. The method of claim 7, wherein, When treating, ammonium sulfate is also added.

10. The method of claim 9, wherein, The mass ratio of the ammonium sulfate to N-methylpyrrolidone in the to-be-treated object is 1:(1-10).

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