Tetradesmus lagerheimii and application of Tetradesmus lagerheimii

Abstract

The invention relates to a strain of Tetradesmus lagerheimii and application of the strain of Tetradesmus lagerheimii. The preservation number of the four-chain algae provided by the invention is CCTCC (China Center for Type Culture Collection) NO: M 20242882. The strain has strong pollution tolerance and enhanced nutrient substance removal efficiency, and especially under an algae-bacterium symbiosis condition, the strain becomes a promising candidate strain for sustainable aquaculture practice. The metabonomics research reveals the synergistic effect of the indigenous bacteria on the Tetradesmus lagerheimii, and emphasizes the importance of the bacterial metabolite in promoting the growth of the algae. The discovery highlights the potential of utilizing algae-bacteria symbiosis to develop an environment-friendly and economical wastewater management strategy.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment, and in particular relates to a Tetrades muslagerheimii and application of the same. Background Art

[0002] With the rapid development of my country's aquaculture industry, the amount of aquaculture wastewater is also growing rapidly. Untreated aquaculture wastewater is directly discharged into the natural environment, and the toxic and harmful substances in it will seriously pollute natural water bodies, harm aquatic life, destroy the natural ecology, and affect human health. Currently, the commonly used aquaculture wastewater treatment methods have problems such as high cost and incomplete treatment of pollutants. Therefore, it is urgent to develop efficient, low-cost and sustainable aquaculture wastewater treatment technology to solve this challenge.

[0003] Microalgae is a type of autotrophic organism that can grow through photosynthesis. Microalgae grows fast, has strong environmental adaptability, and can grow and reproduce in aquaculture wastewater. Related studies have shown that microalgae can remove pollutants such as nitrogen and phosphorus from aquaculture wastewater through nutritional growth. Microalgae can also remove pollutants such as heavy metals, antibiotics, hormones and pathogens from aquaculture wastewater through adsorption and degradation mechanisms. Microalgae cells are rich in a variety of nutrients such as oils, proteins and polysaccharides, and can be used to produce biofuels, protein feed and some biologically active substances. Therefore, using microalgae to treat aquaculture wastewater can not only purify the water quality of aquaculture wastewater, but also convert pollutants in aquaculture wastewater into products with use value, thereby realizing the resource utilization of wastewater.

[0004] Chlorella is one of the most commonly used microalgae for wastewater treatment, and it has strong pollution tolerance. However, the spoilage of Chlorella caused by bacterial contamination poses a major challenge in the wastewater treatment process. Therefore, screening an algae strain with strong symbiotic potential with bacteria and good pollution tolerance is crucial to achieve large-scale and efficient wastewater treatment. Summary of the invention

[0005] The present invention aims to solve one of the technical problems existing in the prior art at least to a certain extent. To this end, the present invention provides a use of Tetradesmus lagerheimii.

[0006] According to one aspect of the present invention, there is provided Tetradesmus lagerheimii with a deposit number of CCTCC NO: M20242882.

[0007] According to another aspect of the present invention, provided is the use of Tetradesmus lagerheimii with a deposit number of CCTCC NO: M20242882 in reducing nutrients in water bodies.

[0008] According to another aspect of the present invention, provided is the use of Tetradesmus lagerheimii with a deposit number of CCTCC NO: M20242882 and bacteria such as Blastomonas and Porphyrobacter from the algal bacterial community in reducing nutrients in water.

[0009] Preferably, the nutrient salt is soluble inorganic nitrogen.

[0010] According to one aspect of the present invention, provided is the use of at least one substance selected from the group consisting of vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid and sphingosine in promoting the growth of Tetrades muslagerheimii with a deposit number of CCTCC NO: M 20242882 and reducing nutrients in water.

[0011] According to one aspect of the present invention, a method for reducing nutrient salts in a water body is provided, wherein Tetradesmus lagerheimii grows in a water body, and the water body contains at least one of vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid and sphingosine.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a Tetradesmus lagerheimii that can be used for wastewater treatment. Tetradesmus lagerheimii is a microalgae strain with strong pollution tolerance, suitable for biological treatment of aquaculture tailwater. Especially under algae-bacteria symbiotic conditions, it becomes a promising candidate species for sustainable aquaculture practices. Metabolomics studies revealed the synergistic growth effect of indigenous bacteria (such as Gemmatimonas and Porphyromonas) and Tetradesmus lagerheimii, emphasizing the importance of bacterial metabolites (vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid and neuraminic acid) in promoting algae growth. This discovery highlights the potential of using algae-bacteria symbiosis to develop environmentally friendly and economical aquaculture waste management strategies. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0014] Figure 1 A diagram showing the separation and screening of Tetradesmus lagerheimii is shown;

[0015] Figure 2 The morphological diagram and phylogenetic tree of Tetraselena lunatus are shown, A. Morphological diagram of Tetraselena lunatus; B. Molecular phylogenetic tree constructed based on ITS sequences;

[0016] Figure 3 The growth parameters of Tetraselena lunatum and Chlorella vulgaris, and the pollutant removal rates in domestic wastewater and aquaculture wastewater are shown. Different letters in the figure represent significant differences among multiple treatment groups during the growth cycle.

[0017] Figure 4 The figure shows the removal rate of pollutants by Tetraselena luna in aquaculture wastewater and the growth parameters of the algae strain, A. pollutant removal rate; B. Tetraselena luna biomass; C. algae growth rate; D. fluorescence parameter (Fv / Fm); different letters in the figure represent significant differences between the two treatment groups during the growth cycle;

[0018] Figure 5 Figure 2 shows the algae-bacteria symbiosis and bacterial community in aquaculture tail water. A. Scanning electron microscope image of algae-bacteria symbiosis; B. Heat map of relative abundance of free bacteria during cultivation; C. Heat map of relative abundance of algal bacteria during cultivation; D. Network analysis between Tetraselena lunatum and free bacterial community; red line: positive correlation; red nodes: bacteria directly positively correlated with algae; blue line: negative correlation; blue nodes: bacteria directly negatively correlated with algae;

[0019] Figure 6 The abundance of four bacterial genera in the algae and water column are shown: A. Blastomonas abundance; B. Porphyrobacter abundance; C. Aquimonas abundance; D. Phenylobacterium abundance;

[0020] Figure 7 The differential metabolites between the two treatment groups, the bacterial group and the sterile group, and their correlation with Tetraselena luna and dominant bacteria are shown. A. Volcano plot of differential metabolite characteristics; B. Heat map of the association between differential metabolites and the abundance of Tetraselena luna and free-living bacteria; C. The promoting effect of the four metabolites on Tetraselena luna. DETAILED DESCRIPTION

[0021] The following examples are provided to allow those skilled in the art to more clearly understand the present invention. It should be noted that the following examples do not limit the scope of protection claimed in the present invention and are only illustrative examples. The raw materials, reagents or devices mentioned in the following examples, unless otherwise specified, can be obtained from commercial sources or by known existing methods.

[0022] Microbial material: Tetradesmus lagerheimii, deposited in the China Center for Type Culture Collection on December 23, 2024, the deposit address is: China Center for Type Culture Collection, Wuhan University, Bayi Road, Wuchang District, Wuhan City, Hubei Province, the deposit number is: CCTCC NO:M 20242882, and the algae species bank naming number is: COFHNU-0412.

[0023] Omics assays were performed by Shanghai Paisono Biotechnology Co., Ltd.

[0024] Example 1 Screening and identification of Tetraselena lunatum strains

[0025] Isolation and screening of Tetradesmus lagerheimii:

[0026] like Figure 1 As shown, by collecting natural water samples, using capillary tubes to pick algae, single algal cells are selectively transferred to a 96-well plate pre-filled with BG11 culture medium, the water sample is spread on BG11 solid culture medium, and the pure single target algal strain is isolated and transferred to a triangular flask for culture.

[0027] Identification of Tetradesmus lagerheimii:

[0028] The algae strains screened above were placed under an optical microscope to observe the morphology of the algae strains. The optical microscope photos are as follows: Figure 2 As shown in A, the algae strain is composed of a true qualitative colony of 4 cells, the colony cells are connected to each other in the middle of their cell side walls, the single cell is moon-shaped, the cell wall is smooth, the chromatophore is peripheral, plate-shaped, cup-shaped, 1, with 1 to 2 pyrenoids. Based on the morphological characteristics, the algae strain obtained was preliminarily identified as a species of the genus Tetradesmus of the family Scenedesmaceae.

[0029] Use Vazyme Plant Direct PCR Kit PD 105 direct amplification kit, centrifuge 1mL of cultured algae liquid and collect algae mud, then take 100μL of lysis solution and add it to the algae mud, mix well and transfer to PCR tube. Place the PCR tube in a PCR instrument for lysis treatment at 95℃, centrifuge after treatment, and the supernatant is the template DNA. Take the genome of the screened algae strain, and perform PCR amplification with universal primers of ITS gene to identify the type of algae strain. The primer sequences for PCR amplification are as follows:

[0030] 18SF: 5'-GTAGTCATATGCTTGTCTC-3',

[0031] 18SR: 5'-CTTCCGTCAATTCCTTTAAG-3',

[0032] Using sample genomic DNA as template, the above primers were used for PCR reaction, and the system was as follows:

[0033]

[0034] The reaction conditions for 18SrDNA sequence were as follows: ① 94℃ for 3 min; ② 94℃ for 30 s; ③ 53℃ for 30 s; ④ 72℃ for 1 min; ⑤ ② to ④ repeated 30 times; ⑥ 72℃ for 7 min.

[0035] The size of the target band of the PCR amplification product is 1109 bp. After sequencing, the nucleotide sequence of the ITS gene fragment is

[0036] , a phylogenetic tree was constructed using this sequence, and the results are as follows Figure 2 As shown in B, the algae strain screened above was identified as Tetradesmus lagerheimii.

[0037] Tetradesmus lagerheimii COFHNU-0412 was deposited in the China Center for Type Culture Collection on December 23, 2024. The deposit address is: China Center for Type Culture Collection, Wuhan University, Bayi Road, Wuchang District, Wuhan City, Hubei Province, with the deposit number: CCTCC NO:M 20242882.

[0038] Example 2 Comparison of pollution tolerance between Tetraselena lunatum and Chlorella vulgaris

[0039] Aquaculture tailwater samples were obtained from Henan Hongji Niu Trout Aquatic Products Co., Ltd. Domestic wastewater samples were obtained from Xinxiang Drainage Engineering Co., Ltd. The present invention designed 8 experimental groups to evaluate the efficiency of Tetraselena lunatum and Chlorella vulgaris in treating two types of wastewater under sterile and indigenous bacterial conditions.

[0040] Domestic sewage and aquaculture tailwater were used in the study. The experimental groups included: Tetraselena lunatei treating domestic sewage with or without indigenous bacteria, Tetraselena lunatei treating aquaculture tailwater with or without indigenous bacteria, Chlorella vulgaris treating domestic sewage with or without indigenous bacteria, and Chlorella vulgaris treating aquaculture tailwater with or without indigenous bacteria.

[0041] The indigenous bacteria in the wastewater were eliminated by autoclaving at 121°C for 20 minutes, and the original wastewater was used directly in the group with indigenous bacteria. The pH value was adjusted to 7.5. Algae were cultured in a 1L photobioreactor with an inoculation density of 9.2 mg / L and the culture temperature was maintained at 25°C. The culture lasted for 6 days, with three replicates set for each treatment group, and the algal growth parameters and the concentration of nutrients in the wastewater were measured daily.

[0042] The results showed that both domestic wastewater and aquaculture raw water were in a hypertrophic state. Domestic wastewater showed high concentrations of ammonia nitrogen, while aquaculture tailwater raw water was mainly composed of high concentrations of nitrate nitrogen and nitrite nitrogen (Table 1). After sterilization, slight changes in nutrient concentrations were detected in the two types of wastewater, which was manifested as slightly lower nutrient concentrations in the sterilized wastewater than in the raw water. After 6 days of cultivation, the biomass accumulation of both algae in domestic sewage was higher than that in aquaculture tailwater, which may be due to the depletion of phosphorus concentration in the latter. Compared with common Chlorella, Tetraselena luna showed higher growth rates and nutrient removal rates in all treatments ( Figure 3 In the aquaculture wastewater with the participation of indigenous bacteria, the biomass of Tetraselena lunatus increased by 401%, showing better algal growth rate and nutrient removal efficiency. Especially in the aquaculture tailwater, the biomass accumulation of Tetraselena lunatus was 102.4% higher than that of the sterilized group ( Figure 3 ).

[0043] Table 1 Nutrient concentrations in domestic wastewater and aquaculture wastewater (μg / L)

[0044]

[0045] Example 3 Strong decontamination performance of Tetraselena lunate on aquaculture wastewater with the participation of indigenous bacteria

[0046] In order to further explore the scalability and treatment effect of the collaboration between indigenous bacteria and Tetraselena lunatus in the treatment efficiency of aquaculture tailwater, the present invention set up two experimental groups: a sterilized group and a bacterial group to evaluate the treatment efficiency during large-scale cultivation. The experiment was carried out in a 50-liter glass tube photobioreactor commonly used in large-scale production. The algae were cultured at 6×10 5 The photobioreactor was placed in a sunlight chamber with a temperature range of 19.0-32.6°C. Three replicates were grown for a 6-day culture period. Evaluations included algal growth, nutrient concentrations, microbial community changes, and metabolite production.

[0047] At the end of the incubation period, both groups almost completely utilized the dissolved organic carbon and soluble phosphorus in the tailwater ( Figure 4 a), indicating that the growth of Tetraselena luna has reached the harvest stage. The removal rate of soluble inorganic nitrogen in the bacterial group reached 91.2%, which was 48.4% higher than that in the sterilized group. It can be seen that the positive effect of indigenous bacteria on Tetraselena luna provided strong evidence. The biomass of Tetraselena luna in the sterilized group was significantly higher than that in the bacterial group (P = 0.0153), and a 16.8-fold increase was observed after six days of cultivation ( Figure 4 b) The growth rates of the two groups first increased and then decreased, mainly due to the depletion of nutrients in the tail water ( Figure 4 c). The photosynthetic parameter Fv / Fm ratio was significantly higher in the bacterial group than in the sterilized group on the 2nd and 5th days of culture ( Figure 4 d), indicating that indigenous bacteria promote the growth of Tetraselena lunatus.

[0048] Example 4 Indigenous bacteria participate in the analysis of nutritional components of Tetraselena lunatei

[0049] In order to further clarify the changes in the nutritional components of Tetraselena lunatum when indigenous bacteria participate in the treatment of aquaculture tail water, the present invention sets up two experimental groups: a sterilized group and a bacteria group for comparative study. The culture cycle and culture conditions are the same as those in Example 3.

[0050] At the end of the culture period, some nutrients in the bacterial group and the sterilized group were significantly different (Table 2). Compared with the sterilized group, the bacterial group showed higher chlorophyll a, lutein and cellular polysaccharide production. These compounds are essential for algal photosynthesis, with chlorophyll a and lutein playing a role in light capture and protection, and polysaccharides acting as storage compounds in green algae. The increased production of chlorophyll a, lutein and polysaccharides in the bacterial group (1.17-fold, 1.07-fold and 1.15-fold, respectively) indicated improved light capture and nutrient accumulation capabilities, suggesting that indigenous bacteria have a beneficial effect on the accumulation of total algal production. However, a decrease in the soluble protein content in the bacterial group relative to the sterilized group was also observed, implying that indigenous bacteria have an impact on the metabolic processes of Tetraselena lunatus. The bacterial group showed a higher nutrient removal rate, which is consistent with the increased algal production. The assimilation of nutrients by algal cells is widely considered to be a key mechanism for nutrient removal in wastewater treatment. This suggests that indigenous bacteria enhance algal growth, light-harvesting efficiency, and nutrient accumulation, which are critical for effective nutrient removal from wastewater.

[0051] Table 2 Nutritional components of Tetraselena lunatum in two treatment groups

[0052]

[0053] Different letters in the table represent significant differences between the two treatment groups during the growth cycle (P < 0.05).

[0054] Example 5 Aquaculture Wastewater Treatment Method of the Symbiotic System of Tetradesmus lagerheimii and Bacteria

[0055] The present invention provides a method for treating aquaculture wastewater in a symbiotic system of Tetradesmus lagerheimii and bacteria, including treating wastewater in two experimental groups: a sterilization group (NIB) and a bacteria group (IB). The experiment was cultured in a 50-liter glass pipe photobioreactor commonly used in large-scale production. The culture cycle and culture conditions were the same as those in Example 3.

[0056] In order to reveal the symbiotic system between Tetradesmus lagerheimii and indigenous bacteria, the present invention studied bacterial population composition analysis, metabolomics analysis of algae-bacteria symbiosis, functional verification analysis of key metabolites, bioinformatics and statistical analysis. The operation method of this embodiment is as follows:

[0057] 1 Analysis of bacterial population composition

[0058] During the study, bacterial samples, including both phycobiotic bacteria and free bacteria, were collected from the sterilized group (NIB) and the indigenous bacteria group (IB) every two days to evaluate the changes in bacterial community composition during the growth of the Tetraselena lunatus population. The phycobiotic bacteria were first collected using a 1.2 μm mixed fiber filter, and the free bacteria were then collected using a 0.22 μm mixed fiber filter ( Figure 2 The filters containing the bacterial samples were stored at -80°C for subsequent analysis.

[0059] DNA extraction was performed using the CTAB method (Omega Bio-Tek, Norcross, USA). The purity and concentration of the extracted DNA were evaluated using a spectrophotometer (NanoDrop NC2000, Thermo Fisher Scientific, USA), and the integrity of the DNA was checked by agarose gel electrophoresis. DNA was PCR amplified using universal primers 779F and 1193R. Subsequently, high-throughput sequencing was performed on the NovaSeq 6000PE250 platform (Shanghai Paisono Biotechnology Co., Ltd., China).

[0060] In addition to measuring the commonly used data on relative bacterial abundance, the absolute abundance of bacteria was assessed using copy number to determine whether the algae recruited specific bacteria.

[0061] 2 Metabolomic analysis of algae-bacteria symbiosis

[0062] Ten milliliters of samples were collected from both groups every two days and centrifuged at 1000 × g for 10 min to remove algal cells and particles. The supernatant obtained was then used for non-targeted metabolite analysis, with six replicates per treatment group. The analysis was performed by Shanghai Paisono Biotechnology Co., Ltd. (Shanghai, China). Metabolite identification was performed by comparing with HMDB, METLIN, MassBank, mzCloud databases, and a proprietary library developed by Paisono Biotechnology.

[0063] 3 Functional verification of key metabolites

[0064] In order to verify the promoting effect of key metabolites on Tetraselena lunatum, analytically pure metabolites were purchased for experimental verification. Tetraselena lunatum was inoculated in BG11 medium at a cell density of 6×10 6 At the same time, these metabolites were introduced into the culture medium at different concentrations: 0 (control group), 150 μg / L (low concentration) and 1.5 mg / L (high concentration). The culture was carried out at 25°C and a light intensity of 7200 lux for 6 days. After 6 days, the algal cell density was measured.

[0065] 4 Bioinformatics and statistical analysis

[0066] Successional changes in bacterial communities

[0067] At the end of the cultivation period, the top 15 bacterial operational taxonomic units (OTUs) were selected for further analysis based on relative abundance. A heat map of temporal changes in bacterial abundance was generated using GraphPad Prism 10.1.2. This analysis included both algal bacteria from the bacterial group and free bacteria to comprehensively assess the successional changes in the bacterial community.

[0068] Network analysis and key bacterial species

[0069] In the network analysis, algal abundance and 202 bacterial abundances were used for joint analysis. The Pearson correlation coefficient (R) between these species was calculated using molecular ecological network analysis. To remove redundant information, some bacteria with insufficient connectivity were excluded from the network graph, and only species with robustness (|R|>0.8) and significant correlation (P<0.05) were retained. The network analysis was performed using Gephi version 0.10.1. The topological properties of the nodes, including degree, betweenness, proximity, and centrality, were calculated on the MENAP website. In the network analysis, nodes with higher degree (>30) and lower betweenness centrality values ​​(<250) were identified as key bacterial species in the network analysis.

[0070] Metabolite relationships between algae and bacteria

[0071] Metabolites with relative standard deviation greater than 30% were first excluded. Partial least squares PLS-DA model was used to distinguish the differential metabolites between the two experimental groups, and metabolites with variable importance projection value >1 and P value <0.05 were identified as significant differential metabolites. We inferred the effects of bacterial metabolites on algal growth by examining the Spearman correlation relationship between the differential metabolites and algal and bacterial abundance. Heat maps showing these relationships were generated using the 'psych' and 'ggplot2' packages in Rv4.0.1.

[0072] The results show:

[0073] The changes in indigenous bacteria were further revealed by analyzing the composition of free bacteria and algal bacterial communities in the incubated group. In the original tailwater, the main bacterial genera were Polynucleobacter and Coxiella, accounting for 17.72% and 13.56% of the total abundance, respectively. During the algal cultivation process, significant changes in the composition of indigenous bacterial species were observed. The abundance of Blastomonas, Porphyrobacter, and Rhizolum increased in the free bacteria and algal bacterial communities (see Figure 5 BC), indicating that these bacteria were able to develop in algal cultures. Electron microscopy images revealed a striking recruitment of rod-shaped bacteria by algal cells (see Figure 5 A). Network analysis further explored the relationship between Tetraselena lunatum and the free bacterial community, and found that 11 positively correlated modules and 10 negatively correlated modules were directly related to the algae. Five bacteria (Gemmanuella, Porphyromonas, Rhizobium, Hyphomonas, and Roseococcus) emerged as key species positively correlated with the algae (see Figure 5 D), presumably they benefited from the algal culture.

[0074] In the present invention, four bacteria were significantly recruited by algal cells during the culture process. Compared with free bacteria, the abundance of Gemmatimonas, Porphyromonas, Aquimonas and Phenylobacterium in the algal biosphere increased significantly by 24.75%, 99.54%, 110.03% and 90.82% (see Figure 6 ). Among them, the concentrations of Gemmatimonas and Porphyromonas in the algae were significantly lower than those in the free state at the beginning of the experiment, but this trend was reversed at the end of the experiment, and their concentrations in the algae increased significantly (see Figure 6 AB), indicating that Gemmatimonas and Porphyromonas were derived from indigenous bacteria and subsequently recruited by the algae.

[0075] In the present invention, the concentration of nutrients in the water of the bacterial group was always lower than that of the sterile group, and the algae biomass in the sterile group increased significantly. These findings suggest the presence of microalgae growth-promoting bacteria in the sterile group, which means that the growth of algae is promoted by a metabolite stimulation mechanism rather than nutrient absorption. Compared with the sterile group, on the third day of culture, there were 12 significantly upregulated differential metabolites and 25 significantly downregulated differential metabolites in the bacterial group ( Figure 7 A). By day 6, 22 differential metabolites were significantly upregulated and 17 were significantly downregulated (see Figure 7 A). After excluding the 11 differential metabolites present on day 0, a total of 17 differential metabolites continued to up-regulate on days 3 and 6. We further used heat maps to illustrate the Spearman correlation between the 17 differential metabolites in the bacterial group and Tetraselena lunatus and free bacteria. The results showed that the differential metabolites including vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid and neuraminic acid were significantly positively correlated with the abundance of major bacteria and Tetraselena lunatus (see Figure 7 B). Further studies on the effects of the four metabolites on the growth of Tetraselena lunatus indicated that they all had significant stimulating effects on algal growth (see Figure 7C). 2-ketobutyric acid and vanillyl alcohol showed significant promoting effects on Tetraselena lunatus at low concentrations (2-ketobutyric acid: P = 0.011; vanillyl alcohol: P = 0.046), and neuraminic acid and 8,11,14-eicosatrienoic acid showed significant promoting effects on Tetraselena lunatus at high concentrations (neuraminic acid: P = 0.002; 8,11,14-eicosatrienoic acid: P = 0.035). These results indicate that these metabolites secreted by the main bacteria (vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid and neuraminic acid) can promote the growth of algae.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Tetradesmus lagerheimii with a deposit number of CCTCC NO: M 20242882.

2. Use of Tetradesmus lagerheimii with a preservation number of CCTCC NO: M 20242882 in reducing nutrients in water bodies.

3. The application of Tetradesmus lagerheimii with the deposit number of CCTCC NO:M 20242882 and the bacterial communities Blastomonas and Porphyrobacter in reducing the nutrient salt in water bodies.

4. The use according to claim 2, characterized in that: The nutrient salt is soluble inorganic nitrogen.

5. Use of at least one of vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid and sphingosine in promoting the growth of Tetradesmus lagerheimii with a deposit number of CCTCC NO: M 20242882 or reducing nutrients in water bodies.

6. A method for promoting the growth of Tetradesmuslagerheimii with a deposit number of CCTCC NO: M 20242882, characterized in that: The Tetradesmus lagerheimii is treated with at least one of vanillyl alcohol, 8,11,14-eicosatrienoic acid, 2-ketobutyric acid, and sphingosine.

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