A desert neospira CDCHPC1 from channa maculata and application thereof in purifying inorganic nitrogen and phosphorus in water body

Abstract

The application discloses a desert Caenispirillum deserti CDCHPC1 from Qinhao Island and application of the Caenispirillum deserti CDCHPC1 in purifying inorganic nitrogen and phosphorus in water bodies, and belongs to the technical field of purifying seawater aquaculture water quality by microorganisms. The Caenispirillum deserti CDCHPC1 has been preserved in the Guangdong Provincial Microbial Culture Collection Center, and the preservation number is GDMCC No: 64120, and the preservation time is December 6, 2023. The strain CDCHPC1 disclosed by the application is screened from the gill and digestive tract tissue of Pristipomoides sieboldii in the Qinhao Island sea area, has no adverse effect on farmed fish and shrimp, has strong purifying capacity on nitrite, nitrate and phosphate in the aquaculture water body, and has good environmental adaptability. The application solves the practical demand of purifying the water environment of high-density seawater fish and shrimp culture, and has a wide application prospect in the field of purifying water bodies.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microbial purification of seawater aquaculture water quality, in particular to a desert neospirillum CDCHPC1 from the channa argus and its application in purifying inorganic nitrogen and phosphorus in water bodies. BACKGROUND

[0002] Ammonia nitrogen and nitrite nitrogen are easy to accumulate in high-density intensive aquaculture water bodies, and high concentrations of ammonia nitrogen and nitrite have serious toxic effects on aquatic animals, endangering the health of cultured animals. Commonly used harmful nitrogen purification methods mainly include physical methods, chemical methods and biological methods. Among them, the physical method is to use the adsorption function of water purification materials such as zeolite powder, dolomite powder and coral sand to adsorb and purify pollutants in water bodies. The adsorption capacity is closely related to the physical form of the material, and there is a certain functional limitation. Aquaculture mostly uses water replacement to alleviate water eutrophication. The chemical method uses the strong oxidation reaction of lime, chlorine preparations and other chemical oxidants to purify water quality. The purification effect continuously decreases with the consumption of oxidants, and if used improperly, there is a risk of secondary pollution of water bodies. The biological method mainly uses specific microorganisms, microalgae and aquatic plants and animals to transform and utilize eutrophic substances in water bodies. Compared with physical and chemical methods, it has the characteristics of environmental friendliness and continuous and stable purification function. Some scholars use marine microalgae + shellfish multi-biological combination to remove excess nitrogen and phosphorus nutrients in water bodies; some use alkali grass, sea spinach, mangrove and other salt-tolerant plants for ex-situ purification of seawater aquaculture water environment. The eutrophication level of high-density fish and shrimp intensive aquaculture water bodies is high, the water consumption is large, and the water quality purification efficiency is relatively high. It is more appropriate to use efficient microbial water purification technology. The activated sludge method is a common microbial water purification technology. The activated sludge culture method commonly used in water treatment engineering is mainly in-situ microbial community enrichment culture. Some scholars use activated sludge to enrich and culture nitrifying bacteria. At 30℃, pH 6.5-8.0 and dissolved oxygen 2.0mg / L, the total amount of nitrifying bacteria increased by nearly 20 times. The removal rate of ammonia nitrogen by enriched freshwater nitrifying bacteria was 0.12mg / g·h, and that of seawater nitrifying bacteria was 0.13mg / g·h. However, for the water environment purification application of aquaculture, the activated sludge enrichment culture method has certain shortcomings in ensuring the specificity of dominant bacteria and safety for aquaculture. In practical application, the purified strain expansion culture method has relatively few large-scale applications in water treatment engineering due to the high requirements for the function and growth characteristics of the strain.

[0003] The islands and reefs in the South China Sea are rich in fishery organisms and marine microbial resources. It is more beneficial to improve the adaptability of the strain to the seawater breeding environment, the efficiency of ecological function, and the safety of breeding organisms by excavating bacterial strain resources that can be used for efficient purification of water environment in aquaculture from healthy fish bodies in the South China Sea island and reef sea area. Therefore, it is of great significance to separate the sand bacteria from the marine organisms in the South China Sea and scientifically use the bacteria for water purification according to the actual demand of purifying the water environment of high-density fish and shrimp aquaculture. Although some scholars have carried out a lot of research and exploration on the effect of bacillus, paracoccus, rhodococcus and pseudomonas on purifying the aquaculture water body, but there are few reports on the research and application of purifying the aquaculture water body by using the deep-sea fish source from the South China Sea. SUMMARY

[0004] The purpose of the present application is to provide a Caenispirillum deserti CDCHPC1 from the Xinhang Island fish source and its application in purifying inorganic nitrogen and phosphorus in water, so as to solve the problems existing in the prior art. The strain CDCHPC1 provided by the present application can greatly reduce the concentration of nitrite nitrogen, nitrate and phosphate in water.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following solutions:

[0006] Technical solution one: a Caenispirillum deserti CDCHPC1 from the Xinhang Island fish source, which has been preserved in the Guangdong Provincial Microbial Culture Collection Center, with the preservation number GDMCC No: 64120 and the preservation time December 06, 2023.

[0007] The bacteria are screened from the gills and digestive tract tissues of fresh fish bodies of healthy Pentapodus caninus in the sea area of Xinhang Island in the South China Sea.

[0008] Technical solution two: the application of the Caenispirillum deserti CDCHPC1 in purifying water.

[0009] Further, the water body includes a breeding water body.

[0010] The breeding water body includes a seawater breeding pond water body.

[0011] Further, the purification is to reduce the content of inorganic nitrogen and phosphorus in the water body.

[0012] Technical solution three: the application of the Caenispirillum deserti CDCHPC1 in fish and shrimp high-density zero water change breeding production.

[0013] Technical solution four: a bacterial agent for reducing the content of inorganic nitrogen and phosphorus in water, the bacterial agent comprising the Caenispirillum deserti CDCHPC1.

[0014] Further, the reducing the content of inorganic nitrogen and phosphorus in the water body includes reducing the concentration of nitrite nitrogen, nitrate and phosphate in the water body.

[0015] Compared with the prior art, the present application has the following beneficial effects:

[0016] The strain CDCHPC1 disclosed in the present application is screened from the gill and digestive tract tissue of the Lobocheirus coryphaenoides in the Chenchang Island sea area, has no adverse effect on the cultured fish and shrimp, has a strong removal effect on nitrite, nitrate and phosphate in the water body for fish and shrimp culture, has good environmental adaptability, is suitable for most seawater aquaculture pond water bodies, and is applied to water quality purification of intensive culture of seawater fish and shrimp, so that a good production application effect can be achieved, the concentration of nitrite nitrogen, nitrate and phosphate in the water can be greatly reduced without purchasing and installing complex water environment purification equipment, and the strain has a wide application prospect in the field of water purification. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description only constitute some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0018] Figure 1 Variation of phosphate concentration in water body under different salinity;

[0019] Figure 2 Variation of nitrite nitrogen concentration in water body under different salinity;

[0020] Figure 3 Variation of CDCHPC1 strain amount under different salinity;

[0021] Figure 4 Variation of phosphate concentration in water body under different temperature;

[0022] Figure 5 Variation of nitrite nitrogen concentration in water body under different temperature;

[0023] Figure 6 Variation of nitrate nitrogen concentration in water body under different temperature;

[0024] Figure 7 Variation of CDCHPC1 strain amount under different temperature;

[0025] Figure 8 Variation of phosphate concentration in water body under different pH condition;

[0026] Figure 9 The concentration of nitrite nitrogen salt in water under different pH conditions;

[0027] Figure 10 The concentration of nitrate nitrogen salt in water under different pH conditions;

[0028] Figure 11 The strain amount of CDCHPC1 under different pH conditions. DETAILED DESCRIPTION

[0029] Various exemplary embodiments of the present application will now be described in detail, which should be considered to be illustrative of certain aspects, features and embodiments of the present application, but not limiting of the same.

[0030] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. In addition, where particular ranges of values are given, understand that each intervening value, to the upper or lower limit of the ranges is also specifically included. Each smaller range that falls within the broader ranges is also specifically included in the present application. The upper and lower limits of these smaller ranges can independently be included or excluded in the range.

[0031] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned herein are incorporated by reference to disclose and describe in further detail the methods and / or materials associated with the documents. In the case of conflict between the present specification and any document incorporated by reference, the present specification will control.

[0032] Various modifications and changes can be made to the specific embodiments of the present application described herein without departing from the scope or spirit of the application. Other embodiments of the application will be apparent to those of ordinary skill in the art from the description and examples presented herein. The description and examples are illustrative of the application and are not intended to limit the scope of the application.

[0033] As used herein, the terms "comprise", "comprising", "include", "including", "have", "having" and the like are open-ended and do not exclude additional elements or steps.

[0034] Example 1: Screening and culture of strains

[0035] 1. Strain source and isolation screening

[0036] In the South China Sea, several healthy dog toothed squirel fish (Pentapodus caninus) with a body length of 16-25 cm were collected. The gills and digestive tract tissues of 4-6 fresh fish were placed in a culture medium and incubated at room temperature to obtain samples and store them.

[0037] The sample was incubated in a photosynthetic bacterial liquid medium for 2-6 days at a temperature of 28-35°C. The bacterial liquid was streaked on a photosynthetic bacterial solid plate medium. After 3-5 days, single colonies with good growth performance were selected. Strains that can remove phosphate, nitrate nitrogen, and nitrite nitrogen from water were determined. Strains with good growth performance and obvious removal effect on phosphate, nitrate nitrogen, and nitrite nitrogen were identified and preserved.

[0038] 2. Culture medium

[0039] Photosynthetic bacterial liquid medium: CH3COONa 3g, yeast extract 1g, peptone 5g, MgSO4·7H2O 0.2g, NH4Cl 0.05g, NaCl 28g, NaNO2 0.05g, KNO3 0.18g, KH2PO4 0.01g, growth factor solution 1mL, the above medicines were dissolved in distilled water, constant volume to 1000mL, pH7.0.

[0040] Growth factor solution: MnSO4·H2O 0.25g, FeSO4·7H2O 7g, CaCl2 5g, glutamic acid 0.02g, the above medicines were dissolved in distilled water, constant volume to 100mL, pH7.0.

[0041] Photosynthetic bacterial solid plate medium: add agar powder 20-25g / L to the photosynthetic bacterial liquid medium to prepare a solid plate medium.

[0042] Example 2: Strain identification

[0043] Strains with good growth performance and obvious removal effect on phosphate, nitrate nitrogen, and nitrite nitrogen were identified by 16S rDNA molecules. The species of the strains were determined from the molecular level, combined with bacterial morphological characteristics and physiological and biochemical characteristics. The 16S rDNA sequence analysis mainly followed the following steps:

[0044] 1. Extraction of bacterial genomic DNA:

[0045] Single colony was inoculated in the expansion medium for culture; 1.5 mL of bacterial liquid was centrifuged at 11500 g for 1-2 min, and the supernatant was removed; the bacterial body precipitate was suspended with 200 μL of buffer GA, 20 mg / mL of lysozyme was added, and the mixture was treated at 37°C for 30 min, 20 μL of proteinase K solution was added; 220 μL of buffer GB was added, and the mixture was treated at 70°C for 10 min, and the solution became clear; 220 μL of anhydrous ethanol was added, and the mixture was shaken for 15 s; the solution and flocculent precipitate were added into an adsorption column CB3, and the mixture was centrifuged at 13400 g for 30 s, and the adsorption column CB3 was placed in a collection tube; 500 μL of buffer GD was added, and the mixture was centrifuged at 13400 g for 30 s, and the adsorption column CB3 was placed in a collection tube; 700 μL of rinse liquid PW was added, and the mixture was centrifuged at 13400 g for 30 s, and the adsorption column CB3 was placed in a collection tube; 500 μL of rinse liquid PW was added, and the mixture was centrifuged at 13400 g for 30 s, and the adsorption column CB3 was placed in a collection tube; the mixture was centrifuged at 13400 g for 2 min, and the waste liquid was removed, and the adsorption column CB3 was placed at room temperature for 5 min for air drying; the adsorption column CB was placed in a clean centrifugal tube, 50-200 μL of elution buffer TE was added, and the mixture was placed at room temperature for 3-5 min, and the mixture was centrifuged at 13400 g for 2 min, and the solution was collected into a centrifugal tube; the obtained DNA fragment was detected by agarose gel electrophoresis and ultraviolet spectrophotometer for concentration and purity.

[0046] 2. PCR amplification of 16S rDNA gene

[0047] The bacterial universal primers for amplification of 16S rDNA were synthesized by Shenguo Bioengineering (Shanghai) Co., Ltd., the forward primer 8F was 5'-AGAGTTTGATCCTGGCTCAG-3' (SEQ ID NO. 1), and the reverse primer 1492R was 5'-GGTTACCTTGTTACGACTT-3' (SEQ ID NO. 2);

[0048] The reaction conditions of PCR amplification were as follows: 95°C for 3 min, 95°C for 1 min, 48°C for 1 min, 72°C for 2 min, a total of 30 cycles, and 72°C for 10 min;

[0049] The reaction system of PCR amplification was as follows: 37 μL of sterilized double-distilled water, 1 μL of each primer, 1 μL of Tap enzyme, 5 μL of 10×PCR buffer, and 1 μL of DNA template.

[0050] 3. 16S rDNA sequence determination

[0051] The PCR product was detected by 1.0% agarose gel electrophoresis, and sequencing was performed by Shenguo Bioengineering (Shanghai) Co., Ltd. The measured sequence was as follows:

[0052] CGTCAGATTAGGTAGTTGGTGAGGTAACGGCTCACCCCGCCGACGATCCGTAACTG

[0053] GTCTGAGAGGCTGATCAGCCACGCTGGGACTGATACCCGGCCCAGACTCCTACGGGAG

[0054] GCAGCTGTGGGGAATATTGGACCATGGGCGCAAGCCTGATCCACCCATGCCGCGCGACC

[0055] GAACAAGGCCTTCGGGTTGTAAAGCTCTTTCCCAAGTGACAATGATGACTGTAACTTCT

[0056] GAAGAACCCTCGGCTAACTTCATGCCATCAGCCGCGGCAATACGAAGGGGGCAAGCGT

[0057] TGTTCGCAATTACTGGGCGTAAAGAGCGCGTACGCGGTGTGCATAGTCAGGGGTGAAAT

[0058] CCCGGGGCTCAACCTCGGAATTGCCTTTGATACTAGCACGCTATAATCCGTGATAAGGTG

[0059] GTGGAATGACCAGTGTACATGTGAAATTTTTAGATATTGGTCGGAACACCTGTGGCGAA

[0060] GGCGGCCGCCTGGCGCGGTATTGACGCTGAGGCGCGAAGACGTGGAGAGCAACCAGGA

[0061] TTAGATACCCTGGTAGGCCACGCCGTAAACCCATGAGTGCTAGCTGTTGGCGTGCTTGCC

[0062] GGTCATACCTTTCCGTGGCCCGACTGCCTCCGTTGCCGGTTGGCGCATCGTCTTCGGGTA

[0063] AAGCCAACTCCCATGGTGTGACGGGCGGTGTGTACAAGGCCCGGGAACGTATTCACCGT

[0064] GGCATGCTGATCCACGATTACTAGCGATTCCGACTTCATGCACTCGAGTTGCAGAGTGCA

[0065] ATCCGAACTGAGACATCTTTTGGAGATTAGCTCCACGTCGCCGTGTGGCTGCCCATTGTA

[0066] GATGCCATTGTAGCACGTGTGTAGCCCAGCCCGTAAGGGCCATGAGGACTTGACGTCAT

[0067] CCCCACCTTCCTCCGACTTGTCATCGGCAGTTCCCCTAGAGTGCCCAACTGAATGCTGGC

[0068] AACTAAGGGCGAGGGTTGCGCTCGTTGCGGGACTTAACCCAACATCTCACGACACGAG

[0069] CTGACGACAGCCATGCAGCACCTGTGCGGGATCCAGCCGAACTGAAAGTCTCATCTCTG

[0070] AGACCGCGATCCCCATGTCAAGGGCTGGTAAGGTTCTGCGCGTTGCTTCAAATTAAACC

[0071] ACATGCTCCACCGCTTGTGCGGGCCCCCGTCAATTCCTTTGAGTTTTAACCTTGCGGCCG

[0072] TACTCCCCAGGCGGAGTGCTTAATGCGTTAGCTGCGCCACTGACCTGCAAAGCAGGCCA

[0073] ACAGCTAGCACTCATCGTTTACGGCGTGGACTACCAGGGTATCTAATCCTGTTTGCTCCC

[0074] CACGCTTTCGCGCCTCAGCGTCAATACCGCGCCAGGTGGCCGCCTTCGCCACTGGTGTT

[0075] CTATGCACACCGGCCTACTCCGCTTTACGCCCATAATTT (SEQ ID NO. 3).

[0076] TCTAGCGTGCTAGTATCAAAGGCAATTCCGAGGTTGAGCCCCCGGGATTTTCACCCCTGA

[0077] TCTAGCGTGCTAGTATCAAAGGCAATTCCGAGGTTGAGCCCCCGGGATTTTCACCCCTGA

[0078] 4. Colony morphology and physiological characteristics of the strain

[0079] Colony morphology and physiological characteristics are shown in Table 1.

[0080] Table 1. Colony morphology and physiological characteristics

[0081]

[0082] 5. Identification of the strain

[0083] Based on the 16S rDNA gene sequence analysis, biochemical identification, and morphological characteristics, the strain is identified as Caenispirillum deserti. According to the literature, there is no report on the use of Caenispirillum deserti collected from the bodies of fish in the sea area of Chenchang Island for purifying inorganic nitrogen and phosphorus in the water body of fish and shrimp intensive culture. The strain is named Caenispirillum deserti CDCHPC1. The Caenispirillum deserti CDCHPC1 has been preserved in the Guangdong Microbial Culture Collection Center on December 6, 2023, with the preservation number GDMCC No: 64120 and the preservation address 59 Building, 5th Floor, Guangzhou Xianlie Middle Road 100 Courtyard.

[0084] Example 3. Application of Caenispirillum deserti CDCHPC1

[0085] 1. Removal effect of Caenispirillum deserti CDCHPC1 on inorganic nitrogen and phosphorus in water body under different salinities

[0086] The sterilized seawater fish and shrimp intensive culture pond water (water salinity 25) was used as the basic test water control without adding the strain CDCHPC1. The salinity of the water was adjusted to 5, 10, 25, and 40 by adding distilled water and sea salt, and the strain CDCHPC1 identified in Example 2 was added at 10 5 -10 6The bacteria were inoculated into water bodies with different salinity at 25-30°C, pH 7.8-8.5, and cultured for 6 days with oscillation, and 3 parallel samples were set for each test sample. The changes of the concentrations of phosphate and nitrite nitrogen in the water bodies were monitored every 3 days.

[0087] As shown in Figure 1 , the concentration of phosphate in the control group changed little compared with the initial value, and remained at 8.273-10.135 mg / L; the phosphate removal effect of the bacteria-inoculated groups with salinity of 5-40 was obvious, and the concentration values decreased from 9.928-10.342 mg / L to 0.967-3.792 mg / L on the 3rd day, with a removal rate of 61.8%-90.6%, but the phosphate concentrations in the water bodies of the control group and each bacteria-inoculated salinity group increased to different extents on the 6th day.

[0088] As shown in Figure 2 , the concentration of nitrite nitrogen in the water body of the control group remained at 7.562-9.242 mg / L; the nitrite nitrogen removal effect of the bacteria-inoculated groups with salinity of 25 and 40 was obvious and stable, and the concentration values decreased to 4.016-4.649 mg / L on the 3rd-6th day, with a removal rate of 44.3%-54.8%.

[0089] As shown in Figure 3 , under the conditions of salinity of 5-40, the bacterial amount in the water bodies of each bacteria-inoculated salinity group continued to increase during the test, and the number change interval was 4.0×10 5 -3.9×10 8 / mL.

[0090] It can be seen that the strain CDCHPC1 has good salinity adaptability and can grow normally under the conditions of salinity of 5-40. However, the effect of removing nitrite nitrogen can be achieved only in seawater environment with salinity greater than 25; generally, the comprehensive effect of removing nitrogen and phosphorus in the water body is better on the 3rd day after inoculation, and attention should be paid to controlling the effect time of using bacteria or repeating the use of bacteria on the 3rd day to strengthen or stabilize the purification effect.

[0091] 2. Removal effect of desert neospirillum CDCHPC1 on inorganic nitrogen and phosphorus in water body under different temperatures

[0092] The sterilized seawater fish and shrimp intensive aquaculture pond water body (water salinity 25, pH value 8.0) was used as the basic test water body control and was incubated at 30°C without adding the strain CDCHPC1. The strain CDCHPC1 identified in Example 2 was inoculated into the water body at a concentration of 10 5 -10 6The strain CDCHPC1 was inoculated into test water bodies at different temperatures, and the temperature gradient was set to 10℃, 20℃, 30℃ and 40℃, and the test was cultured at a constant temperature for 6 days, and 3 parallel samples were set for each test group. The changes of phosphate, nitrite nitrogen and nitrate nitrogen concentrations in the water body were monitored every 3 days.

[0093] As shown in Figure 4 , the phosphate concentration of the control group changed little compared with the initial value, and remained at 10.097-11.228 mg / L; the strain CDCHPC1 had good removal effect on phosphate at 10-30℃, and the removal rate could reach 71.2%-87.6% in 6 days, the removal rate of the 40℃ group was 53.2% on the 3rd day, and decreased to 18.7% on the 6th day.

[0094] As shown in Figure 5 , the nitrite nitrogen concentrations of the control group, 10℃ group and 20℃ group changed little compared with the initial value, and remained at 7.328-9.523 mg / L; the strain CDCHPC1 had good removal effect on nitrite nitrogen at 30-40℃, and the removal rate could reach 98.0%-99.6% in 3-6 days.

[0095] As shown in Figure 6 , the nitrate nitrogen concentrations of the control group, 10℃ group and 20℃ group changed little compared with the initial value, and remained at 33.253-37.060 mg / L; the strain CDCHPC1 had good removal effect on nitrate nitrogen at 30-40℃, and the removal rate could reach 72.2%-98.4% on the 6th day.

[0096] As shown in Figure 7 , the bacterial amount in the water body of each temperature group continued to increase during the test under the temperature condition of 10-40℃, and there was little difference in the bacterial amount among the temperature groups on the 6th day, and the number interval was 2.4×10 8 -5.7×10 8 / mL, which was stable at the order of magnitude level of 10 8 / mL.

[0097] It can be seen that the strain CDCHPC1 has good temperature adaptability and can grow normally under the condition of 10-40℃, but considering its purification effect on phosphate, nitrite nitrogen and nitrate nitrogen in water environment, the temperature of 25-30℃ is more appropriate, which also coincides with the suitable water temperature condition of most aquatic animals.

[0098] 3. Removal effect of desert neospirillum CDCHPC1 on inorganic nitrogen and phosphorus in water body under different pH

[0099] The sterilized seawater fish and shrimp intensive aquaculture pond water (water salinity 25, pH value 8.0) was used as the basic test water control, and was incubated at 30°C, without adding strain CDCHPC1. The strain CDCHPC1 identified in Example 2 was inoculated into the test water at 10 5 -10 6 CFU / mL into the test water with different pH values, which were set to 6, 8, and 10, respectively, and incubated at 30°C for 6 days. Each test sample group had three parallel samples. The concentrations of phosphate, nitrite nitrogen, and nitrate nitrogen in the water were monitored every 3 days.

[0100] As shown in Figure 8 , the phosphate concentration of the control group changed little compared with the initial value, and remained at 12.997-14.661 mg / L. Strain CDCHPC1 had good phosphate removal effect at pH 6-pH 10. Relatively speaking, the effect was better under weak alkaline conditions, and the phosphate removal rate of pH 8-pH 10 group was 81.4%-93.7% for 3-6 days, and that of pH 6 group was slightly lower, at 70.4%-82.6%.

[0101] As shown in Figure 9 , the nitrite nitrogen of the control group changed little compared with the initial value, and remained at 8.872-9.179 mg / L. Strain CDCHPC1 had good nitrite nitrogen removal effect at pH 6-pH 10. The effect was better under weak alkaline conditions, and the nitrite nitrogen removal rate of pH 8 group was 95.7%-96.8% for 3-6 days, and that of pH 6 group and pH 10 group was slightly lower, at 71.0%-82.7% and 77.0%-86.1%, respectively.

[0102] As shown in Figure 10 , the nitrate nitrogen of the control group changed little compared with the initial value, and remained at 11.579-13.490 mg / L. Strain CDCHPC1 had good nitrate nitrogen removal effect at pH 6-pH 10. The nitrate nitrogen removal rate of pH 6 group, pH 8 group, and pH 10 group was 55.3%-87.3%, 62.4%-88.8%, and 68.8%-69.5%, respectively, for 3-6 days.

[0103] As shown in Figure 11 , the bacterial amount of each group continued to increase under the conditions of pH 6-pH 10, and there was little difference in the bacterial amount among the pH groups on the 6th day, and the number was stable at the order of magnitude of 10 8 CFU / mL.

[0104] It can be seen that strain CDCHPC1 can adapt to most of the seawater aquaculture pH environment, and can survive and grow well in water with pH 6-pH 10, reaching 10 8The CFU / mL quantity level is high, and the strain has good effects on removing phosphate, nitrite nitrogen and nitrate nitrogen in water bodies.

[0105] Application effect of desert neospirillum CDCHPC1 in high-density zero-water-change aquaculture of fish and shrimp

[0106] The strain CDCHPC1 was tested in high-density zero-water-change aquaculture of prawns in Jiaxi Town of Shanwei, Guangdong and Dianbai of Maoming, Guangdong. The bacterial agent (bacterial concentration 10 4 -10 6 CFU / mL) and brown sugar (0.05 kg / m 3 ) were added into the aquaculture water within 10 days of stocking, and then the bacterial agent was regularly added every 6 days. The total alkalinity and pH value of the water body were stabilized by using lime water, and the dissolved oxygen of the water body was increased by using oxygenation mechanical equipment. The results showed that the application effect of the bacterial agent was good, and the strain CDCHPC1 had no adverse effects on the aquaculture fish and shrimp. Among them, the Dianbai aquaculture base passed the on-site test organized by the Maoming Agricultural Technology Extension Center. The prawns were cultured for 90 days, and the tilapia was cultured for 120 days. The average weight of the prawns was 14.7 g per tail, the body length was 12.1 cm, the calculated yield per mu was 10 kg / m 3 , and the survival rate was 82%. The average weight of the fish was 826 g per tail, the calculated yield per mu was 23 kg / m 3 , and the survival rate was 70%. The water body conditions during the culture process are shown in Table 2. The water temperature was 23-28℃, the salinity was 10-15, the pH value was 7.0-8.5, the dissolved oxygen concentration was 5.02-6.50 mg / L, the ammonia nitrogen was 0.145 mg / L, and the nitrite nitrogen was 0.119 mg / L.

[0107] Table 2 Water quality conditions of the water body cultured with the strain CDCHPC1

[0108]

[0109] The above-described embodiments are only descriptions of the preferred modes of the present application and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. A type of desert spirochete from fish sourced from Chenhang Island ( Caenispirillum deserti CDCHPC1, characterized in that, It has been preserved in Guangdong Microbial Culture Collection Center, the preservation number is GDMCC No: 64120, and the preservation time is December 6, 2023.

2. The application of the Neospirillum deserti CDCHPC1 in purifying water bodies according to claim 1.

3. Use according to claim 2, characterized in that, The water bodies include aquaculture water bodies.

4. Use according to claim 2, characterized in that, The purification is the purification of inorganic nitrogen and phosphorus in the water bodies.

5. The application of the Neospirillum deserti CDCHPC1 in high-density zero-water-change aquaculture production according to claim 1.

6. A microbial agent for reducing the content of inorganic nitrogen and phosphorus in a water body, characterized in that, The bacterial agent includes the Neospirillum deserti CDCHPC1 according to claim 1.

Images