Organic metal calcium salt compound for relieving aluminum toxicity and application thereof

Abstract

The invention provides an organic metal calcium salt compound for relieving aluminum toxicity and application thereof, and belongs to the technical field of environmental restoration. The organic metal calcium salt compound is a folinate calcium salt hydrate (FCa), the chemical formula is C20H21CaN7O7. NH2O, and n is equal to 1-3. The folic acid analogue and the calcium salt are integrated to form a stable coordination structure, so that the bioavailability of Al < 3 + > in the environment is effectively reduced, the stress effect of aluminum toxicity on plants is relieved, and the compound has the characteristics of environment friendliness and remarkable slow-release effect, and is suitable for repairing and treating water bodies and acidified soil.

Description

Technical Field

[0001] The invention provides an organic metal calcium salt complex for alleviating aluminum toxicity and application thereof, belonging to the technical field of environmental remediation. Background Art

[0002] Against the backdrop of accelerating global industrialization, the problem of acid rain caused by environmental pollution is becoming increasingly serious, leading to the acidification of soil and water bodies. Aluminum pollution has become an increasingly serious environmental problem. Under acidic conditions, aluminum will form Al(OH)3 and further transform into the active Al(H2O)6 3+ , namely Al 3+ . Studies have shown that Al 3+ It is highly active, mobile, and bioabsorbable, and has severe toxic effects on both terrestrial and aquatic organisms. As a rapidly growing aquatic plant that is sensitive to environmental changes, duckweed has become an ideal model for studying plant responses to environmental stress.

[0003] Aluminum, a common metal element in soil and water, has complex physiological effects on plant growth and development. At low concentrations, it may have certain physiological regulatory effects on some plants, but once it exceeds the tolerance threshold of the plant, it will have toxic effects on the plant, affecting important physiological processes such as photosynthesis, respiration, and root development.

[0004] Aluminum pollution primarily originates from natural processes and human activities. Naturally, the weathering of minerals can release aluminum into water and soil. Furthermore, the corrosion of aluminum products by acid rain and other acidic fluids can release aluminum into water bodies, causing aluminum pollution. Human activities, including large-scale mining, industrial production, and the widespread use of aluminum products, have resulted in severe wastewater, waste gas, and waste residue pollution, becoming the primary source of aluminum pollution in water bodies.

[0005] Therefore, in view of this, the existing structure is studied and improved, and an organic metal calcium salt complex that alleviates aluminum toxicity and its application are proposed to solve the above-mentioned problems. Summary of the Invention

[0006] The purpose of the present invention is to provide an organic metal calcium salt complex for alleviating aluminum toxicity and its application, by integrating folic acid analogs with calcium salts to form a stable coordination structure, effectively reducing Al in the environment. 3 + bioavailability, alleviates the stress effect of aluminum toxicity on plants and the complex is environmentally friendly and has a significant slow-release effect, making it suitable for the remediation of water bodies and acidified soils.

[0007] In order to solve the above problems, the present invention proposes a technical solution: an organic metal calcium salt complex for alleviating aluminum toxicity and its application, the organic metal calcium salt complex is folinic acid calcium salt hydrate (FCa), the chemical formula of which is C 20 H 21 CaN7O7·nH2O, wherein n=1-3.

[0008] The preparation method is as follows: tetrahydrofolic acid is reacted with formic anhydride at pH 8-10 to generate folinic acid, the generated folinic acid is then neutralized with a calcium chloride solution at 25-40° C., and then recrystallized with an ethanol-water mixed solvent to obtain folinic acid calcium salt hydrate.

[0009] The application of the organic metal calcium salt complex in the restoration of aluminum-contaminated water bodies can reduce the aluminum content in duckweed by ≥35%, reduce the reactive oxygen species (ROS) level by ≥25%, and restore the chlorophyll content to more than 134% of the normal level.

[0010] The growth system for repairing aluminum-contaminated water bodies is duckweed.

[0011] The aluminum ion concentration in the aluminum-contaminated water body ranges from 10 to 200 mg / L.

[0012] After the folinic acid calcium salt hydrate is added for 7 days, the reproduction rate of duckweed fronds serving as a growth system is increased by ≥40%, and the length of the root system is increased by ≥50%.

[0013] The added concentration of the folinic acid calcium salt hydrate is 100-400 μM, and the treatment time is 5-10 days.

[0014] Due to the adoption of the above technical solution, the beneficial effects of the organic metal calcium salt complex for alleviating aluminum toxicity and its application in the present invention are as follows:

[0015] 1. The present invention's organometallic calcium salt complex, calcium folinate hydrate, significantly alleviates the harmful effects of aluminum toxicity on duckweed. Experiments have shown that the addition of this complex significantly reduces aluminum content in duckweed, significantly reduces reactive oxygen levels, and restores or even exceeds normal chlorophyll content. This effectively improves duckweed's growth in aluminum-contaminated environments and enhances its resistance to aluminum toxicity.

[0016] 2. The compound of the present invention can promote the growth and reproduction of duckweed, significantly increasing the reproduction rate of duckweed fronds and significantly increasing the length of the root system. This not only helps duckweed survive in aluminum-contaminated water bodies, but also allows the duckweed to absorb more aluminum ions through its growth, further improving the efficiency of water remediation.

[0017] 3. The composite material and its application method used in the present invention belong to the category of bioremediation technology, do not introduce other harmful chemicals, avoid secondary pollution, meet environmental protection requirements, and have good ecological benefits.

[0018] 4. The preparation method of the complex is relatively simple, and its application in the remediation of aluminum-contaminated water bodies is also relatively convenient. It does not require complicated equipment and processes, and has good practicality and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 1 .

[0021] Figure 2 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 2 .

[0022] Figure 3 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 3 .

[0023] Figure 4 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 4 .

[0024] Figure 5 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 5 .

[0025] Figure 6 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 6 .

[0026] Figure 7 The experimental results of the present invention show an organic metal calcium salt complex for alleviating aluminum toxicity and its application. Figure 7 . DETAILED DESCRIPTION

[0027] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. It is obvious that the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0028] Example 1

[0029] Effects of exogenous folinic acid calcium salt hydrate (FCa) on duckweed growth under aluminum stress.

[0030] This study used a gradient concentration method to investigate the regulatory effect of organometallic calcium salt complex (FCa) on the physiological response of duckweed (Lemna minor) under aluminum toxicity stress. The experimental design included 20 duckweed individuals with uniform physiological status, which were transplanted into a 750μMAl 3 + basal culture system, six FCa treatment groups (0, 100, 200, 400, 800, and 1600 μM) were simultaneously established, with three independent biological replicates for each treatment group. To maintain nutritional homeostasis, each treatment group was supplemented with 1 / 2 Murashige & Skoog (MS) basal salt solution to ensure that all culture conditions, except for the target treatment variable, remained consistent. The experiment was conducted in a strictly controlled incubator for 7 consecutive days. During this period, growth parameters such as plant height growth, frond division frequency, and biomass accumulation of duckweed were systematically recorded. A dose-response model was established to analyze the efficacy of FCa in alleviating aluminum toxicity.

[0031] By the attached Figure 1 The results show that the organometallic calcium salt complex (FCa) exhibits a significant concentration-dependent mitigation effect on aluminum toxicity. The data show that the maximum mitigation effect was observed in the 200 μM FCa treatment group, where the relative growth rate of duckweed increased by 69.2% compared to the aluminum-only treatment group, and the biomass accumulation increased by 214.4%. By comparing the growth of duckweed under different FCa concentrations, we found that the mitigation effect on aluminum stress reached its peak when the FCa concentration reached 200 μM. Notably, the mitigation effect showed a dose-dependent weakening trend when the FCa concentration exceeded 200 μM, and the mitigation effect began to decline. At 1600 μM, the frequency of duckweed frond division was almost zero, suggesting that high FCa concentrations may trigger secondary stress effects such as ion imbalance or accumulation of reactive oxygen species (ROS). The results confirmed that folinic acid calcium salt hydrate (FCa) at a concentration of 200 μM can effectively alleviate the damage of aluminum toxicity to plant cell membrane integrity and metabolic function, and its optimal effective concentration range is 100-400 μM, providing a quantitative basis for precise application in subsequent environmental remediation.

[0032] Example 2

[0033] The roots of duckweed were stained with DAB and NBT and cytological observation was performed to observe the effect of folinic acid calcium salt hydrate on reactive oxygen species.

[0034] The intact root system of duckweed (Lemna minor) was taken, rinsed with running water three times to remove surface pollutants, transferred to a 1.5 mL centrifuge tube, and vertically immersed in premixed DAB staining working solution (containing 20× DAB buffer, 20× substrate and 20× color developer, prepared freshly for use). The root system was incubated in the dark at 28±1°C for 20 min, and the root system was rinsed with precooled distilled water three times (5 min each time) to terminate the peroxidase activity. The stained root system was spread on a slide, and after adding mounting medium, the degree of oxidative browning of the xylem was observed under an Olympus BX53 fluorescence microscope (40× objective lens).

[0035] The pre-cooled roots were transferred to a culture dish containing NBT staining working solution (containing 10 mM NaN3 and protected from light) and placed in a 25-37°C light incubator (light intensity 120 μmol / m -2 s -1 ) were incubated for 30 min (time gradient setting), and the reaction was terminated by immersing in distilled water. The superoxide anion (O2 -· ) accumulation sites.

[0036] By the attached Figure 2 Quantitative staining analysis revealed the characteristics of the oxidative stress response induced by aluminum stress. The DAB and NBT staining intensities in the roots of duckweed plants treated with aluminum were significantly higher than those in the control group, indicating that aluminum toxicity induces abnormal accumulation of reactive oxygen species in the plant roots. Notably, the DAB and NBT staining intensities in the FCa-treated group (200 μM) were lower than those in the aluminum-treated group. This ROS-scavenging ability is closely related to the improved oxidative stress markers and antioxidant enzyme activities following FCa treatment.

[0037] Example 3

[0038] The folate metabolic pathway may affect duckweed's tolerance to aluminum stress.

[0039] Duckweed was treated according to the same procedures as in Example 1, except that 20 μM L-5-methyltetrahydrofolate, 0.2 μM dihydrofolate reductase (DHFR) inhibitor methotrexate (MTX), and 200 μM FCa were added to demonstrate the alleviating effect of folinic acid calcium salt hydrate on aluminum toxicity through the folic acid metabolic pathway.

[0040] By the attached Figure 3It can be seen that metabolic pathway analysis reveals the key role of folic acid metabolism regulation in alleviating aluminum toxicity. When folinic acid calcium salt hydrate (FCa, 200μM) was added or tetrahydrofolate (THF, 20μM) was directly supplemented, the proliferation rate of duckweed fronds increased by 48.2% and 68.8% respectively compared with the group treated with aluminum alone, the fresh weight biomass increased by 181.4% and 192.5%, and the root elongation length increased by 104.2% and 121.0%, indicating that activation of the folic acid metabolic pathway can significantly improve aluminum stress damage, among which THF has the best repair effect. When methotrexate (MTX, a DHFR-specific inhibitor, 0.2μM) was combined with aluminum toxicity, the proliferation rate of duckweed fronds further decreased by 52.6% compared with the group treated with aluminum alone, and the root development inhibition rate intensified to 42.9%, further confirming that blocking DHFR activity will aggravate the effects of aluminum toxicity. Activating the folate metabolic pathway (e.g., through supplementation with FCa or THF) significantly enhanced duckweed's tolerance to aluminum stress, whereas methotrexate (MTX), an inhibitor of dihydrofolate reductase (DHFR) function, amplified the toxic effects of aluminum. These results clearly demonstrate that activating the folate metabolic pathway significantly enhances duckweed's tolerance to aluminum stress.

[0041] Example 4

[0042] This is the effect of folinic acid calcium salt hydrate (FCa) on the antioxidant enzyme activity, MDA content and total sulfhydryl content of duckweed under aluminum stress.

[0043] The plant materials were pre-cultured in 1 / 2 Murashige & Skoog (MS) basal salt medium and then treated with 750 μmol / L Al 3 + (aluminum stress group) and 200μmol / LFCa (calcium treatment group) were acutely treated for 1h. In order to analyze the antioxidant response mechanism of plants to aluminum stress, samples were collected immediately after treatment: 0.1g duckweed tissue was accurately weighed, 1mL of pre-cooled PBS extraction buffer (containing 1% PVPP) was added, and mechanical homogenization was performed in an ice bath. After the homogenate was centrifuged at 8000×g at 4℃ for 10min, the supernatant was taken and placed on ice for later use. The activities of the three antioxidant enzymes were determined by spectrophotometry, referring to the instructions of the CAT (EC1.11.1.6), POD (EC1.11.1.7) and SOD (EC1.15.1.1) detection kits of Nanjing Jiancheng Bioengineering Institute. All experiments were set up with three biological replicates, and the enzyme activity unit was expressed as U / mg protein.

[0044] The malondialdehyde (MDA) content was determined by thiobarbituric acid (TBA) colorimetric method. Take 0.1g duckweed sample, add 2mL pre-cooled 50mmol / L phosphate buffer (pH7.8, containing 1% PVPP), and grind in an ice bath to a homogenate. The homogenate was centrifuged at 4°C and 10000×g for 15min, and the supernatant was taken as the test solution. The reaction system contained 0.5mL supernatant, 2mL0.5% TBA solution (dissolved in 20% trichloroacetic acid), and the reaction was reacted in a boiling water bath for 20min and then quickly terminated in an ice bath. After cooling, centrifuge at 4°C and 10000×g for 10min, and take the supernatant to measure the absorbance at wavelengths of 532nm and 600nm. According to the extinction coefficient of 155mmol-1·cm -1 The MDA content was calculated and the results were expressed as μmol / g fresh weight (FW). Three biological replicates were set for each group of experiments.

[0045] Sulfhydryl groups in organisms primarily include glutathione (GSH) sulfhydryl groups and protein sulfhydryl groups. The former not only repairs oxidatively damaged proteins but also participates in the scavenging of reactive oxygen species, while the latter plays an important role in maintaining protein conformation. Protein sulfhydryl content can be indirectly determined by measuring total sulfhydryl and GSH content. Approximately 0.1 g of protein was weighed, added to 1 mL of the extract, and a 10% homogenate was prepared. Centrifuge at 8000 g for 10 minutes at room temperature, and the supernatant was collected for analysis. The absorbance was measured at a wavelength of 412 nm using a spectrophotometer.

[0046] Attachment Figure 4 AC revealed the dynamic response characteristics of the plant antioxidant defense system under aluminum stress. Data showed that in the initial stage of aluminum exposure (≤1 hour), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activities showed significant stage activation of 363.5%, 22.8%, and 176.8%, respectively, indicating that they resist oxidative damage through staged metabolic enhancement. When 200μM FCa was applied, the antioxidant enzyme activities showed a decay kinetic characteristic: at 60 minutes after treatment, the CAT / POD / SOD activities were reduced by 17.8%, 8.0%, and 28.7%, respectively, compared with the aluminum-only treatment group. This phenomenon confirmed that exogenous FCa intervention can effectively alleviate aluminum-induced oxidative damage. This dynamic change in enzyme activity reveals the molecular mechanism by which FCa alleviates the effects of aluminum toxicity by regulating antioxidant defense pathways.

[0047] like Figure 4As shown in Figure 2, aluminum stress treatment for one hour significantly increased lipid peroxidation in duckweed, with malondialdehyde (MDA) content reaching 8.54 nmol / g. However, treatment with FCa significantly reduced MDA content to 6.26 nmol / g. This result suggests that exogenous FCa-mediated antioxidant regulation can effectively inhibit aluminum stress-induced membrane lipid peroxidation and mitigate oxidative damage to cell membranes caused by reactive oxygen species (ROS).

[0048] Systematic analysis based on the thiol metabolic network shows that thiol compounds in organisms constitute a dynamic redox buffer system: GSH achieves dual regulation of ROS clearance and protein oxidative damage repair through the thiol-disulfide bond cycle, while thiol proteins ensure the functional integrity of key metabolic enzymes by maintaining the conformation of the enzyme active center. Figure 4 E shows that the total thiol level of duckweed surged to 44.59 μmol / g in the early stage of aluminum stress (≤1 hour). It is worth noting that after FCa treatment, the total thiol content returned to 24.42 μmol / g. The reconstruction of this dynamic balance reveals that FCa effectively alleviates aluminum-induced oxidative stress damage by regulating thiol redox homeostasis.

[0049] Example 5

[0050] Effects of folinic acid calcium salt hydrate on chlorophyll content in duckweed under aluminum stress.

[0051] Take a whole plant of fresh duckweed, wash it with distilled water first, and then use filter paper to absorb the residual moisture on the surface. Accurately weigh about 0.1g of duckweed and place it in a mortar. In a dark place or low light environment, add an appropriate amount of extract to the mortar and grind the duckweed tissue until it is completely broken. After grinding, cover the mortar with tin foil and let it stand at room temperature for 3 hours. During this period, you can shake the mortar gently to promote the full release of chlorophyll. The sign of complete extraction is that the bottom tissue residue is nearly white, indicating that the chlorophyll extraction is complete. Finally, carefully transfer 1mL of the upper extract and place it in a 1mL glass cuvette. Use a spectrophotometer to measure its absorbance at 663nm and 645nm, respectively, for subsequent calculation of the chlorophyll content.

[0052] By the attached Figure 5It can be seen that in the aluminum stress treatment group, the Chla, Chlb and total chlorophyll contents decreased significantly by 28.1%, 17.7% and 23.8% respectively compared with the control group. This phenomenon indicates that aluminum ions may have dually inhibited the homeostasis of chlorophyll by inducing oxidative damage (ROS accumulation) and destroying the chloroplast membrane system. After exogenous addition of folinic acid calcium salt (FCa), the Chla, Chlb and total chlorophyll contents recovered to 112.1%, 166.6% and 134.2% of the control group, respectively. The chlorophyll content of duckweed not only returned to normal levels, but even significantly exceeded that of the unstressed control group. This result fully demonstrates that FCa may exhibit significant repair potential by activating the antioxidant support system and the synergistic effect of the chlorophyll synthesis pathway. This discovery provides a new theoretical basis and practical guidance for the study of plant anti-aluminum toxicity mechanisms and the application of folic acid metabolism regulation.

[0053] Example 6

[0054] Calcium folinate hydrate can affect the aluminum ion content in the system.

[0055] Accurately weigh 0.1 g of pretreated duckweed tissue, place it in a mortar, add 1 mL of deionized water, and grind it thoroughly in an ice bath. Subsequently, the grinding liquid was transferred to a centrifuge tube, centrifuged at 8000g for 10 minutes at 4°C, and the supernatant was collected for later use. Next, the pH of the supernatant was adjusted to a weakly acidic environment (pH≈6), and chrome azuro blue S (CAS) and hexadecyltrimethylammonium bromide (CTAB) were added as color developers. Aluminum ions form a stable blue ternary complex with the two. The absorbance value was measured at a wavelength of 620 nm using a spectrophotometer, and the baseline was corrected with a reagent blank. The aluminum content in duckweed tissue was calculated by the standard curve method.

[0056] By the attached Figure 6As can be seen, after 7 days of treatment, the aluminum ion concentration in the solution of the aluminum-stressed group (without FCa addition) significantly decreased to 41.90 mg / L, significantly lower than that of the unstressed control group. Combined with analysis of duckweed's physiological responses, it is speculated that its aluminum tolerance mechanism may involve the synergistic effects of multiple pathways, including ion exchange, cell wall adsorption, complexation by root exudates, fixation by the root iron plaque, and active absorption. After the addition of FCa, the aluminum ion concentration in the solution further decreased to 21.57 mg / L, a decrease of 48.5%. This suggests that FCa may enhance the system's dealumination capacity through direct interaction with free aluminum ions (such as adsorption or precipitation). On the other hand, the aluminum content in duckweed tissue in the aluminum-stressed group was as high as 36.42 mg / L, significantly higher than that in the control group. However, after the addition of FCa, aluminum accumulation in the duckweed decreased to 23.53 mg / L, a decrease of 35.4%. This result indicates that FCa can not only effectively reduce the aluminum ion content in the solution, but also significantly reduce the accumulation of aluminum ions in duckweed, thereby alleviating the potential toxic effects of aluminum stress on duckweed.

[0057] Example 7

[0058] Verification of genes related to folate metabolism

[0059] The experiment used A. thaliana ecotype Columbia (Col-0) as the wild type (WT) plant, and a large number of mutants such as fpgs-sk (SAIL_510_E12), ggh1-sk (SALK_002474C), and adcs-sk (SALK_095283C) were obtained from the NASC platform. The seeds were surface sterilized for 8 minutes using 6% sodium hypochlorite and sterile water in a 1:1 ratio, and then rinsed three times with distilled sterile water. The seeds were vernalized overnight in a 4°C refrigerator and grown in square Petri dishes containing 1 / 2 Murashige & Skoog (MS) basal salt mixture, 1% (w / v) sucrose, 0.7% (w / v) agar, and the culture medium pH was 5.4. The square Petri dishes were placed vertically at a 65° angle in an artificial climate chamber at a temperature of 22°C and a light intensity of 300 μmol·m -2 ·s -1 The cultures were cultured under continuous light conditions with a photoperiod of 16 h light / 8 h dark.

[0060] By the attached Figure 7 It can be seen that at 750 μM Al 3Under stress conditions, the adcs-sk mutant showed hypersensitivity to aluminum stress, suggesting that disruption of the folate biosynthesis pathway may weaken the plant's stress resistance. In addition, the FPGS gene of the fpgs-sk mutant encodes folate polyglutamate synthase, an enzyme that plays a central role in maintaining folate polyglutamate levels in the cytoplasm and mitochondria and is essential for maintaining folate homeostasis and cell proliferation. 3 Under aluminum stress, the fpgs-sk mutant also exhibits hypersensitivity to aluminum stress, suggesting that disturbances in folate metabolism may affect plant stress responses. In contrast, the GGH1 gene in the ggh1-sk mutant encodes a γ-glutamyl hydrolase, which participates in tetrahydrofolate metabolism by cleaving the glutamate tail and functions in the vacuole. Under aluminum stress, the ggh1-sk mutant exhibits insensitivity to aluminum stress, possibly because the loss of GGH1 reduces tetrahydrofolate degradation, thereby indirectly maintaining folate homeostasis and enhancing plant stress resistance.

[0061] The present invention and its implementation methods are described above. This description is not restrictive. In short, if ordinary technicians in this field are inspired by it and do not depart from the purpose of the invention, they can creatively design structures and embodiments similar to the technical solution, which should fall within the scope of protection of the present invention.

Claims

1. An organic metal calcium salt complex for alleviating aluminum toxicity and its application, characterized in that: The organic metal calcium salt complex is folinic acid calcium salt hydrate (FCa), with the chemical formula C 20 H 21 CaN7O7·nH2O, wherein n=1-3.

2. The organic metal calcium salt complex for alleviating aluminum toxicity and its application according to claim 1, characterized in that: The preparation method is as follows: tetrahydrofolic acid is reacted with formic anhydride at pH 8-10 to generate folinic acid, the generated folinic acid is then neutralized with a calcium chloride solution at 25-40° C., and then recrystallized with an ethanol-water mixed solvent to obtain folinic acid calcium salt hydrate.

3. The organic metal calcium salt complex for alleviating aluminum toxicity and its use according to claim 1, characterized in that: The application of the organic metal calcium salt complex in the restoration of aluminum-contaminated water bodies can reduce the aluminum content in duckweed by ≥35%, reduce the reactive oxygen species (ROS) level by ≥25%, and restore the chlorophyll content to more than 134% of the normal level.

4. The organic metal calcium salt complex for alleviating aluminum toxicity and its use according to claim 1, characterized in that: The growth system for repairing aluminum-contaminated water bodies is duckweed.

5. The organic metal calcium salt complex for alleviating aluminum toxicity and its use according to claim 1, characterized in that: The aluminum ion concentration in the aluminum-contaminated water body ranges from 10 to 200 mg / L.

6. The organic metal calcium salt complex for alleviating aluminum toxicity and its use according to claim 1, characterized in that: After the folinic acid calcium salt hydrate is added for 7 days, the reproduction rate of duckweed fronds serving as a growth system is increased by ≥40%, and the length of the root system is increased by ≥50%.

7. The organic metal calcium salt complex for alleviating aluminum toxicity and its use according to claim 1, characterized in that: The added concentration of the folinic acid calcium salt hydrate is 100-400 μM, and the treatment time is 5-10 days.

Images