A method for promoting growth of spirulina

Abstract

The application relates to a method for promoting the growth of spirulina, and aims to solve the problems of low light utilization rate in the growth of spirulina and insufficient utilization of effective components in the culture medium in large-scale cultivation. The method comprises the following steps: adding dimethyl sulfoxide into spirulina algae liquid to obtain mixed liquid A; then adding TPE-PPO to obtain mixed liquid B; and finally culturing for 4-24 days under 4000-12000 lux. The addition of 40 muM TPE-PPO can increase the OD value of spirulina by 45%, the total lipid content by 71%, and the total protein content by 77%. In addition, in the range of 5-100 muM, the biomass and chlorophyll a content of TPE-PPO Platymonas subcordiformis are further increased with the increase of the TPE-PPO concentration. The application is applied to the technical field of ecological environment protection.

Description

Technical Field

[0001] This invention relates to a method for promoting the growth of spirulina. Background Technology

[0002] Microalgae, as highly efficient cell factories, possess enormous potential for application in energy, food, and biomedicine due to the accumulation of secondary metabolites during their growth and metabolism. Regulating algal growth to achieve the efficient accumulation of high-value-added products can not only provide sustainable renewable energy but also has significant application potential and economic value in addressing the global energy crisis and achieving carbon neutrality. Therefore, finding more efficient methods to promote microalgal growth is a current research focus. Spirulina is renowned for its strong photosynthetic capacity and rapid growth rate. However, spirulina cultivation requires stringent environmental conditions, and as algal density increases, light penetration is limited, easily leading to photolimiting or photoinhibition. Furthermore, during large-scale cultivation, spirulina exhibits low efficiency in utilizing carbon and nitrogen sources, necessitating regular replenishment, increasing production costs. Moreover, the actual yield of current algal cultivation still differs significantly from the theoretical yield under ideal conditions.

[0003] Methods to promote algal growth can be broadly categorized into physical regulation, chemical regulation, biological regulation, and regulation using novel materials. In the cultivation of algal microorganisms, light energy is the primary driving force for photoautotrophic growth. However, in high-density cultivation systems, light attenuation is severe; surface algal cells face photoinhibition and UV damage, while deeper cells are in a state of starvation due to limited light. Photosynthetically active radiation (PAR) accounts for only a small portion of the solar spectrum, and microalgae primarily absorb red and blue light, with extremely low utilization rates of green, yellow, and violet light. Therefore, in recent years, research on promoting algal growth by improving light irradiation methods, light quality, and light intensity during the cultivation process has received widespread attention.

[0004] Unlike traditional fluorescent dyes, inorganic quantum dots, and conventional light-converting materials that aggregate and quench in water, AIE materials can aggregate in water to enhance fluorescence. This makes them suitable for the high water content, complex ionic composition, and abundant biological interfaces found in microalgae cultivation systems, resulting in better signal stability and functional reliability. Furthermore, by modulating their absorption and emission wavelengths, AIE materials can convert inefficient spectra into more readily captureable light by chlorophyll, thereby improving light energy utilization efficiency and enhancing photosynthesis, significantly overcoming the limitations of traditional supplemental lighting. Simultaneously, their excellent fluorescence imaging capabilities allow for simultaneous visualization and tracking of material distribution, cellular uptake, and intracellular responses during the control process, achieving precise regulation. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of low light utilization during the growth of Spirulina and insufficient utilization of effective components in the culture medium during large-scale cultivation, and to provide a method for promoting the growth of Spirulina.

[0006] The present invention provides a method for promoting the growth of Spirulina as follows: Dimethyl sulfoxide is added to the Spirulina algal solution to obtain mixture A; then TPE-PPO (1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]prop-2-yn-1-one) is added to obtain mixture B; wherein the concentration of TPE-PPO in mixture B is 5 μM-100 μM, and then the mixture is cultured at 4000-12000 lux for 4-24 days to complete the process.

[0007] TPE-PPO possesses excellent molecular designability, and its emission wavelength is complementary to the absorption wavelength of Spirulina phycobilisomes. Co-culturing it with Spirulina can convert inefficient light into more readily captureable light by the phycobilisomes, thereby improving light energy utilization efficiency and enhancing photosynthesis. This promotes the growth of Spirulina itself, as well as the growth of its secondary metabolites—lipids, proteins, and other highly bioactive substances. Furthermore, after scaling up the culture, the added drug showed an even more significant promoting effect on Spirulina. This provides a more favorable experimental scheme for large-scale Spirulina cultivation, and the method is simple and easy to implement.

[0008] By directly adding the drug to the culture medium of Spirulina and co-culturing it with Spirulina platensis, the results showed that the addition of 40 µM TPE-PPO increased the OD value of Spirulina by 45%, total lipid content by 71%, and total protein content by 77%. Furthermore, within the range of 5-100 µM, the biomass and chlorophyll a content of Spirulina platensis increased further with increasing TPE-PPO concentration. In addition, ecological safety tests revealed that TPE-PPO had almost no effect on the growth of Chlorella, exhibiting good biocompatibility. Moreover, both scanning electron microscopy and confocal microscopy images showed that it did not cause morphological or structural damage to the algae, nor did it stimulate any changes in the surface state of the algae. Furthermore, after scaling up the experiment 20 times, we found that 40 µM TPE-PPO could increase the content of spirulina lipids, polysaccharides, and proteins by 50%, 29%, and 70%, respectively, and its dry weight increased by 95.6% and carbon fixation efficiency increased by 127%. All of the above data can prove that it has high application potential in large-scale aquaculture.

[0009] Then, by analyzing the changes in genes of various lipid and protein types in *Spirulina platensis* after the addition of TPE-PPO, we found that genes related to functional unsaturated lipids were significantly upregulated, giving them great potential for application in anti-inflammation, anti-oxidation, and prevention of cardiovascular and cerebrovascular diseases. Conversely, genes related to certain structural phospholipids and free acids were significantly downregulated. Furthermore, we found that the downregulated lipids exhibited compensatory over-regulation among similar lipid groups, demonstrating that the downregulated lipid types did not significantly affect the inherent nutritional value of *Spirulina platensis*. In fact, they not only increased the lipid content of *Spirulina platensis* but also significantly enhanced its nutritional value. Moreover, the addition of TPE-PPO deceived the sensory system of *Spirulina platensis*, causing it to mistakenly believe it was in an ideal high-nitrogen, high-nutrient growth environment, thus inducing a growth mode of rapid proliferation and protein synthesis. Attached Figure Description

[0010] Figure 1 This is a route diagram for the synthesis of TPE-PPO;

[0011] Figure 2 The carbon NMR spectrum of TPE-PPO;

[0012] Figure 3 The 1H NMR spectrum of TPE-PPO;

[0013] Figure 4 The changes in algal biomass (AC), chlorophyll a (DF), and carotenoids (GI) under different light intensities are shown.

[0014] Figure 5 The effects of different concentrations of TPE-PPO on the biomass (A), chlorophyll a (B), carotenoids (C), protein (D), lipids (E), and polysaccharides (F) of Spirulina platensis;

[0015] Figure 6 Changes in related lipid genes;

[0016] Figure 7 This refers to changes in the genes of related proteins. Detailed Implementation

[0017] Specific Implementation Method 1: One method for promoting the growth of Spirulina in this implementation method is as follows: add dimethyl sulfoxide to the Spirulina algal solution to obtain mixture A; then add TPE-PPO to obtain mixture B; wherein the concentration of TPE-PPO in mixture B is 5μM-100μM, and then culture at 4000-12000 lux for 4-24 days to complete the process.

[0018] Specific Implementation Method Two: The difference between this implementation method and Specific Implementation Method One is that the preparation method of TPE-PPO is as follows: 1. Mix 1-(4-bromophenyl)-1,2,2-triphenylethylene and 4-formylphenylboronic acid, and then add toluene, tetrabutylammonium bromide and potassium carbonate aqueous solution in sequence. Under nitrogen protection, stir at room temperature, add Pd(PPh3)4 to react. After the reaction is complete, extract, dry, distill under reduced pressure and separate by column chromatography to obtain the aldehyde intermediate 4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-carboxaldehyde;

[0019] 2. The aldehyde intermediate 4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-carboxaldehyde was dissolved in THF, and then Grignard reagent-acetylenyl magnesium bromide solution was added dropwise under ice bath. After stirring, the reaction was quenched after it was completed, and the propargyl alcohol intermediate 1-acetylenyl-1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]methanol was obtained by column chromatography.

[0020] 3. The propargyl alcohol intermediate 1-ethynyl-1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]methanol was dissolved in DCM, manganese dioxide was added, the reaction was stirred at room temperature, filtered, and the filtrate was washed with saturated brine. After drying and vacuum distillation, the target product 1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]prop-2-yn-1-one (TPE-PPO) was obtained by column chromatography. Other steps are the same as in Specific Embodiment 1.

[0021] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that: after adding Pd(PPh3)4 in step 1, the reaction is carried out at 90°C for 24 hours. The other steps are the same as in Specific Implementation Method 1 or 2.

[0022] Specific Implementation Method Four: This implementation method differs from Specific Implementation Method Two or Three in that: in step two, the Grignard reagent-acetylated magnesium bromide solution is a solution formed by dissolving the Grignard reagent-acetylated magnesium bromide in tetrahydrofuran. The other steps are the same as in Specific Implementation Method Two or Three.

[0023] Specific Implementation Method Five: The difference between this implementation method and Specific Implementation Methods One to Four is that the stirring described in step two is carried out under ice bath conditions for 1 hour, followed by stirring at room temperature overnight. The other steps are the same as those in Specific Implementation Methods One to Four.

[0024] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the reaction is quenched with a saturated ammonium chloride solution in step two. The other steps are the same as in Specific Implementation Methods One to Five.

[0025] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One through Six in that the concentration of dimethyl sulfoxide in mixture A is 1 mmol / L. The other steps are the same as in Specific Implementation Methods One through Six.

[0026] Specific Implementation Method Eight: The difference between this implementation method and Specific Implementation Methods One to Seven is that the TPE-PPO concentration in mixture B is 40 μM. The other steps are the same as in Specific Implementation Methods One to Seven.

[0027] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One through Eight in that it involves cultivation for 20 days under a light intensity of 4000 lux. The other steps are the same as in Specific Implementation Methods One through Eight.

[0028] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One through Nine in that: The algal culture is obtained by: expanding the algal strain using Zarrouk medium; harvesting cells by centrifugation at 3000 rpm for 10 min during the logarithmic growth phase; and then transferring the cells to a 250 mL Erlenmeyer flask containing 100 mL of Zarrouk medium for further culture, until the initial cell density of the algae reaches approximately 1 × 10⁻⁶ cells / mL. 6 The algal solution was obtained by incubating at a concentration of cells / mL at a temperature of 25 ± 1℃, with a light-dark cycle of 16 h: 8 h and a culture period of 16-20 days. Other steps are the same as those in specific implementation methods one through nine.

[0029] The scope of this invention is not limited to the above-described embodiments; a combination of one or more specific embodiments can also achieve the purpose of the invention.

[0030] Example 1: A method for promoting the growth of spirulina in this example is as follows:

[0031] Prepare the raw materials needed for the experiment: synthesized TPE-PPO, Spirulina strain FACHB-439 purchased from the Freshwater Algae Culture Bank of the Institute of Hydrobiology, Chinese Academy of Sciences (Wuhan), Zarrouk culture medium (components shown in Table 1), and dimethyl sulfoxide (purity >= 99.5%).

[0032] Table 1

[0033]

[0034] The method for synthesizing TPE-PPO is as follows: 1-(4-bromophenyl)-1,2,2-triphenylethylene (TPE-Br) (10 mmol, 4.11 g) and 4-formylphenylboronic acid (15 mmol, 2.25 g) are placed in a 250 mL round-bottom flask equipped with a magnetic stir bar. Then, 60 mL of toluene, tetrabutylammonium bromide (1 mmol, 0.32 g), and 18 mL of potassium carbonate aqueous solution are added sequentially. Under nitrogen protection, the mixture is stirred at room temperature for 30 min. Pd(PPh3)4 (0.1 mmol, 0.16 g) is added, and the reaction is carried out at 90 °C for 24 h. After confirming the completeness of the reaction by TLC spotting, the aldehyde intermediate 4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-carboxaldehyde (TPE-PCA) is obtained by extraction, drying, vacuum distillation, and column chromatography.

[0035] TPE-PCA (4 mmol, 1.75 g) was dissolved in 40 mL of THF, and then a solution (12 mmol) of Grignard reagent-acetylenyl magnesium bromide dissolved in tetrahydrofuran was slowly added dropwise under ice bath conditions. After stirring for 1 h under ice bath conditions, the mixture was stirred overnight at room temperature. After confirming that the reaction of the starting material was complete, the reaction was quenched with saturated ammonium chloride solution. After post-treatment, column chromatography was used to separate the propargyl alcohol intermediate 1-acetylenyl-1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]methanol.

[0036] The above intermediate was dissolved in 80 mL of DCM, and 10.4 g of manganese dioxide was added. The mixture was stirred at room temperature for 2 h, and excess solid was removed by filtration. The filtrate was washed with saturated brine, dried, and distilled under reduced pressure before being separated by column chromatography to obtain the target product 1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]prop-2-ynthin-1-one (TPE-PPO). The synthetic route is shown in [reference needed]. Figure 1 The carbon NMR and hydrogen NMR spectra of the synthesized target compounds are shown in [reference needed]. Figure 2 and Figure 3 As shown in the figure, TPE-PPO was successfully synthesized in this embodiment.

[0037] Algal culture: The algal strain was expanded using Zarrouk medium, and cells were harvested by centrifugation at 3000 rpm for 10 min during the logarithmic growth phase. The collected Spirulina were transferred to 250 mL Erlenmeyer flasks containing 100 mL of Zarrouk medium to achieve an initial cell density of approximately 1 × 10⁻⁶ cells / mL. 6cells / mL. All experiments were repeated three times. The culture temperature was 25 ± 1℃, and the light-dark cycle was 16 h: 8 h, with 16 hours of light and 8 hours of darkness periodically changing. The light source was provided by a controllable incandescent lamp in the incubator. To ensure uniform light, the Erlenmeyer flasks containing algae were manually shaken three times a day for a culture period of 16-20 days.

[0038] A control group and a blank group were set up, with only algal solution added. 100 μL of DMSO was added to experimental group one, with a DMSO concentration of 1 mmol / L. Subsequent experimental groups were prepared with 5 μmol / L, 10 μmol / L, 20 μmol / L, and 40 μmol / L TPE-PPO, respectively. Three groups were set up for each parameter, and the average values ​​were taken.

[0039] The effects of different light intensities and TPE-PPO concentrations on the growth promotion of Spirulina were verified. At a TPE-PPO concentration of 10 μmol / L, the changes in algal biomass (AC), chlorophyll a (DF), and carotenoid (GI) under different light intensities were as follows: Figure 4 As shown, both the control and experimental groups exhibited higher algal biomass and chlorophyll a content at 4000 lux compared to 8000 lux and 12000 lux. Conversely, the highest carotenoid content was observed at 12000 lux, likely due to high light stress. Comparing the control and experimental groups, it was found that at 4000 lux, after 20 days of cultivation, 10 μM TPE-PPO increased Spirulina biomass by 16.7%, chlorophyll a by 11.4%, and carotenoids by 12.5%. However, at 24 days of cultivation, both the control and experimental groups showed a significant decrease in biomass, chlorophyll a, and carotenoids, indicating that the optimal cultivation time was 20 days. Comparing the experimental and control groups under light intensities of 8000 lux and 12000 lux, it was found that there was basically no difference in biomass, but the amount of algal chlorophyll a increased by 23.5% and 22.2%, respectively, and the amount of carotenoids increased by 37.2% and 57.1%, respectively.

[0040] The effects of different concentrations of TPE-PPO on the biomass (A), chlorophyll a (B), carotenoids (C), protein (D), lipids (E), and polysaccharides (F) of Spirulina platensis are as follows: Figure 5 As shown in Figure A, before day 16, as the concentration of TPE-PPO increased from 5 μM to 100 μM, the biomass of *Spirulina platensis* increased from 7.8% to 45.7%, exhibiting a clear concentration-dependent growth effect. On day 20, the biomass of the control group remained relatively stable, but the algal biomass of all experimental groups after drug addition showed a significant decrease, possibly due to insufficient energy supply from the culture medium.

[0041] The photosynthetic promoting effect of TPE-PPO was evaluated by quantitative analysis of chlorophyll a (Chl a) and carotenoid content. Figure 5 B illustrates the effect of different concentrations of TPE-PPO on chlorophyll a in *Spirulina platensis*. Results showed that chlorophyll a steadily increased from day 4 to day 12. By day 12, compared to the control group, the chlorophyll a content of algae in the experimental groups treated with 5 μM-100 μM TPE-PPO increased by 83%-200%. From day 16 to day 20, the groups treated with the drug remained essentially unchanged, but a slight decrease in chlorophyll content began to occur in the high-concentration (100 μM) group. During the 20-day culture period, the chlorophyll a concentration in the 40 μM group increased by 62% compared to the control group. Figure 5 C illustrates the changes in carotenoid content in *Spirulina platensis* after the addition of TPE-PPO. During the first 12 days, carotenoid content steadily increased in both the control and experimental groups. From days 12 to 16, the control group continued its steady increase, but most low-concentration experimental groups showed a decreasing or plateauing trend. In contrast, the high-concentration (60 μM and 100 μM) experimental groups showed a significant increase in carotenoid content, reaching growth rates of 85% and 42% respectively by day 16. By day 20, the high-concentration (60 μM and 100 μM) experimental groups remained essentially unchanged, while the 40-60 μM experimental groups experienced a sharp increase in carotenoid content. This may be because, on day 20, facing the depletion of nutrients in the culture medium and the environmental stress of TPE-PPO, *Spirulina platensis* resisted the stress by promoting carotenoid accumulation.

[0042] During the 16-day culture period, the effects of high concentrations (60 μM and 100 μM) on promoting the growth of Spirulina biomass and chlorophyll gradually decreased. Furthermore, the production cost would increase dramatically with the addition of TPE-PPO. Therefore, we chose low concentrations (5-40 μM) to further study its biomass. Figure 5 D illustrates the effect of different concentrations of TPE-PPO on the total protein accumulation of *Spirulina platensis*. Within the concentration range of 5-40 μM, protein accumulation increased with increasing TPE-PPO concentration. Specifically, compared to the control group, during the 16-day culture period, the protein content at 5 μM, 10 μM, 20 μM, and 40 μM increased by 45.2%, 69.6%, 70.2%, and 77.7%, respectively, demonstrating that TPE-PPO not only promoted the growth of *Spirulina platensis* but also increased its protein content. Figure 5 E shows the effect of different concentrations of TPE-PPO on total lipid accumulation in Spirulina platensis. Similar to the protein, as the concentration of TPE-PPO increased from 5-40 μM, the increase in lipid accumulation at day 16 was 37.8%, 74.5%, 73.3%, and 71%, respectively. Figure 5 F illustrates the effects of different concentrations of TPE-PPO on the polysaccharides of *Spirulina platensis*. We found that polysaccharide levels decreased with increasing TPE-PPO concentration. This may be because the algae were not under environmental stress and did not secrete excessive polysaccharides due to stress, while excessive protein and lipid production consumed the nutrients available for polysaccharide production, which is consistent with the findings of Wang et al. Compared to the control group, the polysaccharide levels in the experimental groups decreased by 0.53%, 21.7%, 55.5%, and 86.6% within the 5-40 μM concentration range, respectively.

[0043] Transcriptome analysis was conducted to investigate the potential mechanism of the promoting effect of TPE-PPO (0 μM control group vs. 40 μM treatment group) on Spirulina platensis. Cells exposed to 40 μM TPE-PPO for 16 days at 4000 lux light and 25°C were collected by centrifugation (4000 rpm, 10 min) followed by three washes with sterile culture medium. The cell pellet was rapidly frozen in liquid nitrogen for 30 min and then stored at -80°C until further analysis. The analysis was performed by Shanghai Meiji Biotechnology Co., Ltd. within 2 weeks after sampling to minimize potential errors. Both the control and treatment groups were tested in triplicate.

[0044] By analyzing the corresponding lipid categories that decreased, the results are as follows: Figure 6 As shown, the downregulated lipid types were mainly concentrated in certain structural phospholipids and free acids. Within the same lipid class, such as PC and SM, the downregulation was compensated by the overregulation of similar homologous lipids, indicating that these downregulated lipids did not significantly affect the inherent nutritional value of spirulina. This demonstrates that the addition of TPE-PPO not only increases the lipid content of spirulina but also significantly enhances its nutritional value due to spirulina's metabolic compensation mechanism.

[0045] Analyze changes in related protein genes, such as Figure 7As shown, a large number of translation-related ribosomal proteins were collectively upregulated, indicating an increase in protein content. Furthermore, glutamate dehydrogenase was significantly elevated, demonstrating that nitrogen metabolism within Spirulina was thoroughly activated, providing ample reserves for explosive protein synthesis. The significant upregulation of fus-1 also indicates accelerated ribosomal translation elongation, suggesting that the addition of TPE-PPO may have overcome certain limitations of ribosomes at the transcriptional or translational levels, enabling Spirulina to maintain a high protein turnover rate. Analysis of the downregulated protein types revealed downregulation of enzymes related to nitrate reduction, such as nrtC / narB, demonstrating that Spirulina conserves energy for protein peptide chain production by reducing the synthesis of these enzymes. Moreover, a large number of proteins related to cell membrane / wall remodeling were downregulated, indicating that Spirulina was not under stress. The downregulation of the phycobilisome degradation protein nblA-2 signifies that the cell received a signal of sufficient nitrogen, allowing the phycocyanin, which originally had dynamic turnover characteristics, to be stored as a stable protein reservoir within the cell, maintaining the high protein content of Spirulina.

Claims

1. A method for promoting the growth of spirulina, characterized in that... The method is as follows: add dimethyl sulfoxide to the Spirulina algal solution to obtain mixture A; then add TPE-PPO to obtain mixture B; wherein the concentration of TPE-PPO in mixture B is 5μM-100μM, and then culture at 4000-12000 lux for 4-24 days to complete the process.

2. The method for promoting the growth of spirulina according to claim 1, characterized in that... The preparation method of TPE-PPO is as follows:

1. Mix 1-(4-bromophenyl)-1,2,2-triphenylethylene and 4-formylphenylboronic acid, and then add toluene, tetrabutylammonium bromide and potassium carbonate aqueous solution in sequence. Under nitrogen protection, stir at room temperature, add Pd(PPh3)4 to react. After the reaction is complete, extract, dry, distill under reduced pressure and separate by column chromatography to obtain the aldehyde intermediate 4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-carboxaldehyde; 2. The aldehyde intermediate 4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-carboxaldehyde was dissolved in THF, and then Grignard reagent-acetylenyl magnesium bromide solution was added dropwise under ice bath. After stirring, the reaction was quenched after it was completed, and the propargyl alcohol intermediate 1-acetylenyl-1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]methanol was obtained by column chromatography.

3. The propargyl alcohol intermediate 1-ethynyl-1-[4'-(1,2,2-triphenylvinyl)-[1,1'-biphenyl]-4-yl]methanol was dissolved in DCM, manganese dioxide was added, the reaction was stirred at room temperature, filtered, and the filtrate was washed with saturated brine. After drying and vacuum distillation, the target product TPE-PPO was obtained by column chromatography.

3. The method for promoting the growth of spirulina according to claim 2, characterized in that, After adding Pd(PPh3)4 in step one, the reaction was carried out at 90℃ for 24 h.

4. The method for promoting the growth of Spirulina according to claim 2, characterized in that, In step two, the Grignard reagent-acetylated magnesium bromide solution is a solution formed by dissolving the Grignard reagent-acetylated magnesium bromide in tetrahydrofuran.

5. The method for promoting the growth of spirulina according to claim 2, characterized in that, The stirring described in step two involves stirring in an ice bath for 1 hour, followed by stirring at room temperature overnight.

6. The method for promoting the growth of spirulina according to claim 2, characterized in that, In step two, the reaction is quenched with a saturated ammonium chloride solution.

7. The method for promoting the growth of spirulina according to claim 1, characterized in that, The concentration of dimethyl sulfoxide in mixture A is 1 mmol / L.

8. The method for promoting the growth of spirulina according to claim 1, characterized in that, The concentration of TPE-PPO in mixture B is 40 μM.

9. The method for promoting the growth of Spirulina according to claim 1, characterized in that, After 20 days of cultivation under a light intensity of 4000 lux.

10. The method for promoting the growth of Spirulina according to claim 1, characterized in that, Method for obtaining algal culture: The algal strain was expanded using Zarrouk medium. Cells were harvested by centrifugation at 3000 rpm for 10 min during the logarithmic growth phase, and then transferred to a 250 mL Erlenmeyer flask containing 100 mL of Zarrouk medium for further culture, so that the initial cell density of the algae reached approximately 1 × 10⁻⁶ cells / mL. 6 The algal solution was obtained by culturing at a cell / mL ratio, a temperature of 25 ± 1℃, a light-dark cycle of 16 h : 8 h, and a culture period of 16-20 days.

Images