Strain of Schwermonas Kunming and application thereof in denitrification of water body

Abstract

The invention discloses a strain of Schwermonas kunming and an application thereof in denitrification of a water body, and relates to the technical field of biology. The Kunming Schwermonas sp. Is preserved in the China General Microbiological Culture Collection Center (CGMCC) on April 24, 2024, the preservation address is No.3, No.1 yard, Beichen West Road, Chaoyang District, Beijing, and the preservation number is CGMCC NO.30427. The Kunming Schwermonas sp. According to the present invention, the Stutzeria kunmingensis 9-4 is separated from the water body sample of the crucian carp recirculating water culture system so as to obtain the Stutzeria kunmingensis 9-4, the strain has a good removal effect on nitrate nitrogen, nitrite nitrogen and ammoniacal nitrogen in a water environment, and meanwhile, the removal rate of the Kunming Schwermonas sp. On nitrate nitrogen, nitrite nitrogen and ammoniacal nitrogen can be remarkably increased by adding hematite under the illumination condition; the method can be applied to removal of nitrate nitrogen, nitrite nitrogen and ammoniacal nitrogen in aquaculture water environment and aquaculture tail water.

Description

Technical Field

[0001] The invention relates to the field of biotechnology, in particular to a strain of Kunming stutzerimonas and its application in water body denitrification. Background Art

[0002] China's aquaculture plays a vital role in the world's supply of aquatic products, and its output accounts for more than 60% of the world's total aquaculture output. According to the "China Fisheries Statistical Yearbook 2024", the total output of aquatic products in China in 2023 was 71.1617 million tons, of which 58.0961 million tons were from aquaculture, accounting for 81.6% of the total output. At present, aquaculture mostly adopts high-density, high-nutrient input aquaculture methods, which will inevitably face the problem of large-scale accumulation of nitrogen, which is easy to cause serious harm to farmed aquatic organisms. In addition, excessively accumulated nitrogen will enter the ocean, rivers, and lakes with the discharge of aquaculture tailwater, causing eutrophication of receiving water bodies and affecting the aquatic ecological environment.

[0003] Therefore, how to efficiently treat nitrogen-containing compounds is an important issue that needs to be solved urgently. Summary of the invention

[0004] The purpose of the present invention is to provide a strain of Kunming Stuttgart's bacterium and its application in water denitrification to solve the problems existing in the above-mentioned prior art. The strain has a good removal effect on nitrate nitrogen, nitrite nitrogen and ammonia nitrogen in the water environment, and the addition of hematite under light conditions can significantly improve the removal rate of nitrate nitrogen, nitrite nitrogen and ammonia nitrogen by the strain, and can be applied to the removal of nitrate nitrogen, nitrite nitrogen and ammonia nitrogen in aquaculture water environment and aquaculture tail water.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a strain of Stutzerimonas kunmingensis, which was deposited in the General Microbiology Center (CGMCC) of the China Culture Collection Administration on April 24, 2024, with the deposit address being No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number being CGMCC NO.30427.

[0007] The present invention also provides the use of the above-mentioned Kunming Stuttgartella in removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment.

[0008] The present invention also provides a method for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment, comprising the steps of inoculating the above-mentioned Kunming Stuttgartella into the water environment and removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen.

[0009] The present invention also provides the use of the above-mentioned Kunming Stuttgart bacteria in the preparation of a biological preparation for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment.

[0010] The present invention also provides a biological preparation for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment, wherein the active ingredient includes the above-mentioned Kunming Sterlingmonas.

[0011] Furthermore, the biological agent also includes hematite.

[0012] Furthermore, the biological agent is Kunming Sterlingmonas / hematite composite system I;

[0013] The preparation method of the Kunming Sterlingmonas / hematite composite system comprises the following steps:

[0014] The Kunming Stuttgart bacteria were inoculated into the culture medium and cultured until the fermentation liquid OD 600 The concentration of hematite powder was 0.05-0.3 g / 100 mL, and the culture was continued for 12 h to obtain the Kunming Steineromonas / hematite composite system.

[0015] Furthermore, the biological agent is Kunming Sterlingmonas / hematite composite system II;

[0016] The Kunming Stuttgart / hematite composite system II is prepared by cross-linking the fermentation liquid of the Kunming Stuttgart and the hematite through a sodium alginate-calcium chloride cross-linking method.

[0017] The present invention also provides the use of the above biological agent in removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment.

[0018] The present invention also provides a method for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment using the above-mentioned biological agent, comprising the steps of adding the biological agent into a water environment to remove nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen.

[0019] The present invention discloses the following technical effects:

[0020] The present invention isolates Stutzerimonas kunmingensis 9-4 from a water sample of a crucian carp recirculating aquaculture system. The strain has a good removal effect on nitrate nitrogen, nitrite nitrogen and ammonia nitrogen in the water environment, and the addition of hematite under light conditions can significantly improve the removal rate of nitrate nitrogen, nitrite nitrogen and ammonia nitrogen by the strain. The strain can be applied to the removal of nitrate nitrogen, nitrite nitrogen and ammonia nitrogen in aquaculture water environments and aquaculture tail water. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a statistical chart of the removal rate of nitrate nitrogen by Kunming Sterlingella 9-4 after 8 hours of treatment under different carbon source conditions;

[0023] Figure 2 The statistical graph of the nitrate nitrogen removal rate after 8 hours of treatment by Kunming Sterlingella 9-4 under different carbon-nitrogen ratios (A), treatment time (B), rotation speed (C), temperature (D), pH (E) and NaCl concentration (F);

[0024] Figure 3 The statistical graph of the removal rate of nitrite nitrogen by Kunming Stuttgartella 9-4 after 8 hours of treatment under different carbon-nitrogen ratios (A), treatment time (B), rotation speed (C), temperature (D), pH (E) and NaCl concentration (F);

[0025] Figure 4 The statistical graph of the removal rate of ammonium nitrogen after 8 hours of treatment with Kunming Stuttgart's Bacillus 9-4 under different carbon-nitrogen ratios (A), treatment time (B), rotation speed (C), temperature (D), pH (E) and NaCl concentration (F);

[0026] Figure 5 It is a test diagram of the removal of nitrate nitrogen by the composite system of Kunming Stuttgartella 9-4 / hematite, and the removal of nitrate nitrogen by Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0027] Figure 6 A statistical graph showing changes in nitrite nitrogen content during the removal of nitrate nitrogen by the Kunming Stuttgartella 9-4 / hematite composite system, and by the Kunming Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0028] Figure 7 A statistical graph showing changes in ammonium nitrogen content during the removal of nitrate nitrogen by the Kunming Stuttgartella 9-4 / hematite composite system, the Kunming Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0029] Figure 8 It is a test diagram of the removal of nitrite nitrogen by the composite system of Kunming Stuttgartella 9-4 / hematite, and the removal of nitrite nitrogen by Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0030] Fig. 9 A statistical graph showing changes in nitrate nitrogen content during the removal of nitrite nitrogen by the Kunming Stuttgartella 9-4 / hematite composite system and the Kunming Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0031] Fig.10 A statistical graph showing changes in ammonium nitrogen content in the process of removing nitrite nitrogen from Kunming Stuttgartella 9-4 / hematite composite system, and Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0032] Fig.11 It is a test diagram of the removal of ammonium nitrogen by the composite system of Kunming Stuttgartella 9-4 / hematite, and the removal of ammonium nitrogen by Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0033] Fig.12 A statistical graph showing changes in nitrate nitrogen content during the removal of ammonium nitrogen by the Kunming Stuttgartella 9-4 / hematite composite system, and by the Kunming Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0034] Fig.13 A statistical graph showing changes in nitrite nitrogen content during the removal of ammonium nitrogen by the Kunming Stuttgartella 9-4 / hematite composite system, and by the Kunming Stuttgartella 9-4 and hematite under the conditions of illumination and light avoidance provided by the present invention;

[0035] Fig.14 The present invention provides a statistical graph of the removal rates of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen by the Kunming Stuttgartella 9-4 / hematite composite system and the Kunming Stuttgartella 9-4 after treatment for 18 hours under the conditions of illumination and light avoidance. DETAILED DESCRIPTION

[0036] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0037] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0038] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0039] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0040] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0041] The components of the denitrification medium used in the following examples are (per liter): carbon source added as needed, MgSO4·7H2O0.1g, 1mol / L K2HPO4 stock solution 8.96mL, 1mol / L KH2PO4 stock solution 1.04mL, trace element stock solution 2mL, KNO3, KNO2 or NH4Cl added as needed. The trace element stock solution in the culture medium is composed of the following: Na2EDTA·2H2O0.2g / L, CaCl20.2 g / L, MnCl2·7H2O 0.8g / L, CoCl2·6H2O 0.35g / L, ZnSO40.4 g / L, CuSO40.4g / L, FeSO41 g / L, (NH4)6Mo7O 24 4H2O 0.65g / L.

[0042] Example 1 Strain Isolation, Screening, Identification and Preservation

[0043] 1. Separation and screening

[0044] Water samples from the crucian carp recirculating aquaculture system were collected and inoculated into enrichment medium for expansion culture, and cultured at 28°C for 48 hours. Subsequently, the samples were gradiently diluted with sterile physiological saline, and the dilutions were spread on BTB plates for primary screening, and the blue bacteria around the colonies were separated and purified. Subsequently, the separated bacteria were inoculated into LB liquid medium containing sodium nitrate added to the Büchner tubes for rescreening, and cultured at 16°C for 7 days. The bacteria with bubbles in the Büchner tubes were inoculated into denitrification medium containing sodium nitrate and cultured at 28°C for 24 hours. The fermentation broth was centrifuged at 12000rpm for 1min, and the supernatant was taken to detect the nitrate nitrogen content therein. The denitrification medium containing sodium nitrate without bacteria inoculation was used as a control, and the target strain with a significantly lower nitrate nitrogen content in the denitrification medium compared with the control was selected as the target strain with denitrification ability. After primary screening and rescreening, a bacterial strain 9-4 that can remove nitrate nitrogen was finally selected from the target strains.

[0045] 2. Identification

[0046] Strain 9-4 has the following physiological and biochemical characteristics:

[0047] (1) Strain 9-4 is a Gram-negative bacterium;

[0048] (2) The colonies of strain 9-4 were light yellow, moist, translucent, with irregular edges and a smooth surface;

[0049] (3) Strain 9-4 can be cultured in LB medium.

[0050] (4) Other physiological and biochemical characteristics of strain 9-4 are shown in Table 1.

[0051] Table 1 Physiological and biochemical characteristics of Kunming Sterlethal Bacteria 9-4

[0052]

[0053] Note: “+”: positive; “-”: negative.

[0054] The nucleotide sequence of the 16S rDNA region obtained by PCR amplification of strain 9-4 using universal primers 27F and 1492R is shown in SEQ ID NO.1.

[0055] SEQ ID NO.1:

[0056]

[0057] The strain 9-4 was identified as Stutzerimonas kunmingensis.

[0058] 3. Biological Deposit

[0059] Stutzerimonas kunmingensis 9-4 was deposited in the General Microbiology Center of China Culture Collection Administration (CGMCC) on April 24, 2024. The deposit address is No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC NO.30427.

[0060] Example 2 Carbon source selection for denitrification process of Kunming Sterlingella 9-4

[0061] Kunming Sterlingella 9-4 was inoculated into LB medium and cultured at 28°C until OD 600 The concentration of nitrate-nitrogen in the culture medium was 0.8. 10 mL of fermentation broth was centrifuged at 12000 rpm for 1 min to collect the cells, and then washed three times with sterile saline. The cells were inoculated into denitrification medium containing different carbon sources and 1 mmol / L sodium nitrate, and the effects of sodium citrate, sucrose, glucose, soluble starch, and sodium succinate as carbon sources on the removal of nitrate-nitrogen were tested.

[0062] The experimental results are shown in Figure 1 .

[0063] Result analysis: Sodium citrate and sodium succinate are the optimal carbon sources for the denitrification process of Kunming Stuttgartella 9-4. Sodium citrate is used as the carbon source in the subsequent examples.

[0064] Example 3 Removal of nitrate nitrogen from denitrification medium by Kunming Sterlingella 9-4

[0065] Kunming Sterlingella 9-4 was inoculated into LB medium and cultured at 28°C until OD 600 The 10 mL fermentation broth was centrifuged at 12000 rpm for 1 min to collect the cells, and then washed three times with sterile saline. The cells were inoculated into a denitrification medium containing 1 mmol / L sodium nitrate and cultured for 8 h. The effects of different carbon-nitrogen ratios (mass ratios), treatment time, rotation speed, temperature, pH, and salinity on the removal of nitrate nitrogen were tested.

[0066] The experimental results are shown in Figure 2 .

[0067] Results: When the carbon-nitrogen ratio was 10-25, the treatment time was greater than 5 hours, the rotation speed was 50-150rpm, the temperature was 16-34℃, the pH was 7.5-9, and the NaCl concentration was 0-10g / L, the removal rate of nitrate nitrogen by Kunming St. Petersburg 9-4 was more than 50%. Among them, the optimal carbon-nitrogen ratio was 15, the optimal rotation speed was 50-100, the optimal temperature was 22-34℃, the optimal pH was 7.5, and the optimal NaCl addition concentration was 0mg / L. After 7 hours of treatment, the removal rate of nitrate nitrogen by Kunming St. Petersburg 9-4 was more than 95%. After 8 hours of treatment under the optimal conditions, the removal rate of nitrate nitrogen by Kunming St. Petersburg 9-4 reached 100%, and there was no accumulation of nitrite nitrogen and ammonium nitrogen.

[0068] Example 4 Removal of nitrite nitrogen from denitrification medium by Kunming Stuttgartella 9-4

[0069] Kunming Sterlingella 9-4 was inoculated into LB medium and cultured at 28°C until OD 600 The 10mL fermentation broth was centrifuged at 12000rpm for 1min to collect the cells, and then washed three times with sterile saline. The cells were inoculated into a denitrification medium containing 1mmol / L sodium nitrite and cultured for 8h. The effects of different carbon-nitrogen ratios, treatment time, rotation speed, temperature, pH, and salinity on the removal of nitrite nitrogen were tested.

[0070] The experimental results are shown in Figure 3 .

[0071] Results: When the carbon-nitrogen ratio was 10-25, the treatment time was greater than 4 hours, the rotation speed was 50-150rpm, the temperature was 16-34℃, the pH was 6.5-9, and the NaCl concentration was 0-10g / L, the removal rate of nitrite nitrogen by Kunming St. Petersburg 9-4 was more than 50%. Among them, the optimal carbon-nitrogen ratio was 20-25, the optimal rotation speed was 50-100, the optimal temperature was 22-34℃, the optimal pH was 7.5-8, and the optimal NaCl addition concentration was 0mg / L. After 7 hours of treatment, the removal rate of nitrite nitrogen by Kunming St. Petersburg 9-4 was more than 95%. After 8 hours of treatment under the optimal conditions, the removal rate of nitrite nitrogen by Kunming St. Petersburg 9-4 reached 100%, and there was no accumulation of nitrate nitrogen and ammonium nitrogen.

[0072] Example 5: Removal of ammonium nitrogen from denitrification medium by Kunming Stuttgartella 9-4

[0073] Kunming Sterlingella 9-4 was inoculated into LB medium and cultured at 28°C until OD 600The concentration of 10 mL of fermentation broth was 0.8. The cells were collected by centrifugation at 12000 rpm for 1 min and washed three times with sterile saline. The cells were inoculated into a denitrification medium containing 1 mmol / L ammonium chloride and cultured for 8 h. The effects of different carbon-nitrogen ratios, treatment time, rotation speed, temperature, pH, and salinity on the removal of ammonium nitrogen were tested.

[0074] The experimental results are shown in Figure 4 .

[0075] Results: When the carbon-nitrogen ratio was 10-25, the treatment time was greater than 4 hours, the rotation speed was 50-150rpm, the temperature was 16-34℃, the pH was 6.5-9, and the NaCl concentration was 0-10g / L, the removal rate of ammonium nitrogen by Kunming St. Petersburg 9-4 reached more than 85%. Among them, the optimal carbon-nitrogen ratio was 15-25, the optimal rotation speed was 50-150, the optimal temperature was 22-34℃, the optimal pH was 6.5-7.5, and the optimal NaCl addition concentration was 0mg / L. After 7 hours of treatment, the removal rate of ammonium nitrogen by Kunming St. Petersburg 9-4 reached more than 95%. After 6 hours of treatment under the optimal conditions, the removal rate of ammonium nitrogen by Kunming St. Petersburg 9-4 reached 100%, and there was no accumulation of nitrate nitrogen and nitrite nitrogen.

[0076] Example 6: Removal of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen from denitrification medium by Kunming Sterlingella 9-4 / hematite composite system

[0077] Kunming Sterlingella 9-4 was inoculated into LB medium and cultured at 28°C until OD 600 The concentration of hematite powder was 0.2 g / 100 mL (the amount of hematite powder added may be 0.05-0.3 g / 100 mL), and the culture was continued for 12 h to prepare the Kunming Sterlingella 9-4 / hematite composite system.

[0078] Kunming Stuttgartella 9-4, Kunming Stuttgartella 9-4 / hematite composite system, and hematite were inoculated into denitrification medium containing sodium nitrate, sodium nitrite or ammonium chloride, respectively, and cultured under light conditions for several hours, and the concentration changes of nitrate nitrogen, nitrite nitrogen, and ammonium nitrogen in the culture medium were detected.

[0079] The experimental results are shown in Figure 5-Figure 13 .

[0080] Results: The removal rates of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen by the composite system of Kunming Stuttgartella 9-4 / hematite under light conditions (9-4 / hematite-light) were significantly higher than those by the composite system of Kunming Stuttgartella 9-4 / hematite under light-proof conditions (9-4 / hematite-light-proof) and Stuttgartella 9-4 (9-4-light, 9-4-light-proof). In addition, the addition of hematite alone had no effect on the removal of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen. In the process of removing nitrate nitrogen, there was no accumulation of nitrite nitrogen and ammonium nitrogen at the end of the treatment of the composite system of Kunming Stuttgartella 9-4 / hematite and Stuttgartella 9-4 under light and light-proof conditions. In the process of removing nitrite nitrogen, there was no accumulation of nitrate nitrogen and ammonium nitrogen at the end of treatment of Kunming Stuttgart 9-4 / hematite composite system and Kunming Stuttgart 9-4 under light and dark conditions. In the process of removing ammonia nitrogen, there was no accumulation of nitrate nitrogen and nitrite nitrogen at the end of treatment of Kunming Stuttgart 9-4 / hematite composite system and Kunming Stuttgart 9-4 under light and dark conditions.

[0081] Example 7: Removal of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen from denitrification medium by Kunming Sterlingella 9-4-hematite composite system

[0082] Kunming Sterlingella 9-4 was inoculated into LB medium and cultured at 28°C until OD 600 0.8. Take 100mL of the fermentation broth of Kunming St. Petersburg 9-4 after culture, centrifuge to remove the supernatant and wash twice with sterile ultrapure water. Mix the bacteria with 0.1g of hematite powder in 10mL of 2% sterile sodium alginate solution, add the mixture to 2% CaCl2 solution in mid-air through a syringe, and then place it at 4°C for 2h to configure the Kunming St. Petersburg 9-4 / hematite composite system. Kunming St. Petersburg 9-4, Kunming St. Petersburg 9-4 / hematite composite system, and hematite were inoculated into denitrification culture medium containing sodium nitrate, sodium nitrite or ammonium chloride, respectively, and cultured for 18h under light conditions, and the concentration changes of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen in the culture medium were detected.

[0083] The experimental results are shown in Fig.14 .

[0084] Analysis of results: The removal rates of nitrate nitrogen, nitrite nitrogen and ammonium nitrogen by the composite system of Kunming Steineromonas 9-4 / hematite under light conditions were significantly higher than those by the composite system of Kunming Steineromonas 9-4 / hematite under dark conditions (9-4 / hematite-darkness) and Kunming Steineromonas 9-4 (9-4-light, 9-4-darkness).

[0085] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A strain of Stutzerimonas kunmingensis, characterized in that: The Kunming Sterlingamas was deposited in the General Microbiology Center of the China Microorganism Culture Collection Administration (CGMCC) on April 24, 2024. The deposit address is No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC NO.30427.

2. Use of the Kunming Stuttgartella as claimed in claim 1 in removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment.

3. A method for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in an aqueous environment, characterized in that: The method comprises the steps of inoculating the Kunming Stuttgartella described in claim 1 into a water environment and removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen.

4. Use of the Kunming Stuttgartella according to claim 1 in preparing a biological agent for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment.

5. A biological agent for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in an aquatic environment, characterized in that: The active ingredient comprises the Kunming Stuttgart bacteria described in claim 1.

6. The biological agent according to claim 5, characterized in that The biological agent also includes hematite.

7. The biological agent according to claim 6, characterized in that The biological agent is Kunming Sterlingmonas / hematite composite system I; The preparation method of the Kunming Sterlingmonas / hematite composite system comprises the following steps: The Kunming Stuttgart bacteria were inoculated into the culture medium and cultured until the fermentation liquid OD 600 The concentration of hematite powder was 0.05-0.3 g / 100 mL, and the culture was continued for 12 h to obtain the Kunming Steineromonas / hematite composite system.

8. The biological agent according to claim 6, characterized in that The biological agent is Kunming Sterlingmonas / hematite composite system II; The Kunming Stuttgart / hematite composite system II is prepared by cross-linking the fermentation liquid of the Kunming Stuttgart and the hematite through a sodium alginate-calcium chloride cross-linking method.

9. Use of the biological agent according to any one of claims 5 to 8 for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in an aquatic environment.

10. A method for removing nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen in a water environment using the biological agent according to any one of claims 5 to 8, characterized in that: The method comprises the steps of adding the biological agent into a water environment to remove nitrate nitrogen, nitrite nitrogen and / or ammonia nitrogen.

Images