Preparation and application of green tea extract air broad-spectrum antibacterial disinfectant

Abstract

The invention relates to the field of sanitizers, in particular to preparation and application of a green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green tea extract air broad-spectrum antibacterial sanitizer.The green A novel disinfectant with high stability and long-acting effect is successfully prepared by constructing a natural synergistic antibacterial system taking the green tea extract, the citric acid and the cedar oil as cores and utilizing a strategy of combining a high-pressure homogeneous nano-emulsification technology and a gel slow-release carrier, the characteristics of being natural, safe and environment-friendly are realized, and the preparation method is suitable for industrial production. The industrial problems of irritation and residual hidden dangers of chemical disinfectants, poor stability of natural components, short action time and the like are effectively solved, and the air purifier has wide application prospects in the fields of air purification and surface disinfection in various scenes such as families, medical treatment, traffic and the like.

Description

Technical Field

[0001] This invention relates to the field of disinfectants, and more particularly to the preparation and application of a broad-spectrum antibacterial disinfectant for air made from green tea extract. Background Technology

[0002] Broad-spectrum antibacterial disinfectants for air are a class of preparations that can effectively kill or remove various pathogenic microorganisms such as bacteria, viruses, and fungi in the air. With the continuous improvement of public health awareness, the market demand for efficient, safe, and sustainable air disinfection products is becoming increasingly urgent.

[0003] Currently, this field is moving towards finding natural-source active ingredients to replace traditional chemically synthesized products. Among them, the main active ingredients of green tea extract are catechins, which have shown great application potential due to their recognized antibacterial and antioxidant capabilities.

[0004] In existing technologies, traditional air disinfection products mainly rely on chemically synthesized substances, such as sodium hypochlorite, peracetic acid, and quaternary ammonium salts. Although these ingredients have a rapid bactericidal effect, they generally have an irritating odor, corrosiveness, and potential toxic side effects on humans and the environment. Disinfectants using green tea water extract have limited effectiveness because their single natural ingredients have a relatively narrow antibacterial spectrum. Furthermore, the core active substance in green tea, catechin, is extremely unstable under light, oxygen, and high temperature conditions and is easily oxidized and deactivated, resulting in a short product shelf life and an unsustainable disinfection effect.

[0005] Therefore, based on the relevant technologies mentioned above, there is an urgent need to develop a broad-spectrum antibacterial disinfectant for air made from green tea extract and to develop its application. Summary of the Invention

[0006] In view of this, the purpose of this invention is to propose the preparation and application of a broad-spectrum antibacterial disinfectant for air made from green tea extract, so as to solve the problems of single efficacy, poor stability, short duration of action and ease of use of natural antibacterial components in the prior art.

[0007] To achieve the above objectives, this invention provides a preparation and application of a green tea extract-based broad-spectrum antibacterial disinfectant for air.

[0008] The preparation steps of a broad-spectrum antibacterial disinfectant for air derived from green tea extract are as follows: Step S1: Add the suspending agent sugar to the carrageenan and stir for 3-7 minutes. Add deionized water and stir for 6-8 minutes at 300-400 rpm. Heat to 75-85℃ and stir at 400-500 rpm for 15-25 minutes to obtain the carrageenan solution. Step S2: Add the nanoemulsion concentrate to the carrageenan solution, heat to 50-60℃, stir at 200-300 rpm for 2-4 minutes, then stir at 350-450 rpm for 10-15 minutes to obtain a broad-spectrum antibacterial disinfectant for air.

[0009] Preferably, the mass ratio of the suspending agent, carrageenan and deionized water in step S1 is 0.2-0.5:1:24-26.

[0010] Preferably, the mass ratio of the nanoemulsion concentrate to the carrageenan solution in step S2 is 0.8-1.2:1.

[0011] Preferably, the preparation steps of the nanoemulsion concentrate in step S2 are as follows: Step A1: Add green tea extract and citric acid to deionized water, heat to 35-45℃, stir for 15-25 minutes at 300-400 rpm until dissolved, and obtain the aqueous phase; Step A2: Add vitamin E and Tween-80 to cedar oil, heat to 20-30℃, stir for 3-5 minutes at 200-300 rpm, and the mixture is complete to obtain the oil phase; Step A3: Add the aqueous phase and oil phase to a high-speed shear mill, heat to 40-50℃, rotate at 8000-10000 rpm, and shear at high speed for 8-12 minutes. Transfer to a high-pressure homogenizer, pressurize to 55-65 MPa for 1-3 minutes, pressurize to 75-85 MPa for 1-3 minutes, pressurize to 95-105 MPa for 1-3 minutes, and pressurize to 95-105 MPa for 1-3 minutes. Homogenization is complete, D90 < 200 nm, and a nanoemulsion concentrate is obtained.

[0012] High-pressure homogenization technology is used to encapsulate active ingredients in droplets, improving their stability and reducing the oxidative decomposition of catechins in green tea extract. At the same time, the addition of carrageenan enhances its sustained-release properties, thereby achieving continuous and slow release of effective ingredients and providing long-lasting air purification. In addition, this disinfectant is compatible with traditional spray and atomizing equipment, and can meet the air and surface disinfection needs of different sizes and scenarios, from homes and offices to medical and health institutions and vehicles, making its application range extremely wide.

[0013] Preferably, the mass ratio of green tea extract, citric acid and deionized water in step A1 is 1.8-2.2:1:58-62.

[0014] Preferably, the mass ratio of vitamin E, Tween-80 and cedar oil in step A2 is 0.1-0.3:0.6-1:1.

[0015] Preferably, the mass ratio of the aqueous phase to the oil phase in step A3 is 14-16:1.

[0016] Preferably, the preparation steps of the green tea extract in step A1 are as follows: Add green tea powder to deionized water, mix well, add citric acid, adjust pH to 4.0-5.0, heat to 75-85℃, spin at 300-400 rpm, extract for 20-40 minutes. After extraction, cool to 20-30℃, filter through 200-mesh nylon cloth, filter under vacuum at 0.45μm, and distill under reduced pressure to obtain green tea extract.

[0017] Because it uses natural ingredients such as green tea extract and cedar oil as the core active substances, the use of chemically synthesized disinfectants is reduced. Therefore, the resulting product is non-toxic, non-irritating, and human-friendly. It is also easily degraded in the environment, overcoming the drawbacks of existing chemical disinfectants, such as toxicity, irritation, and environmental pollution. Meanwhile, by scientifically combining green tea extract, citric acid and cedar oil, a triple synergistic antibacterial mechanism was constructed, namely aqueous phase, oil phase and acidic environment. This not only broadened the antibacterial spectrum and showed a highly effective killing effect on a variety of airborne pathogens such as bacteria, fungi and enveloped viruses, but also effectively delayed the development of microbial resistance.

[0018] Preferably, the mass ratio of green tea powder to deionized water is 1:15-20.

[0019] Application of a green tea extract-based broad-spectrum antibacterial disinfectant for air, the disinfectant is mainly used for air purification in spaces, auxiliary infection control in medical and health institutions, maintenance of the internal environment of transportation vehicles, disinfection and deodorization of places with special odors, and internal disinfection of personal items.

[0020] The beneficial effects of this invention are: This invention provides the preparation and application of a broad-spectrum antibacterial disinfectant based on green tea extract. By constructing a natural synergistic antibacterial system centered on green tea extract, citric acid, and cedar oil, and utilizing a strategy combining high-pressure homogenized nanoemulsification technology with a gel sustained-release carrier, this invention successfully prepares a novel disinfectant with high stability and long-lasting effects. Compared with existing technologies, this product not only achieves natural safety and environmental friendliness but also significantly improves broad-spectrum antibacterial activity and ease of use. It effectively solves industry problems such as the irritation and residue risks of chemical disinfectants, as well as the poor stability and short action time of natural components. It has broad application prospects in air purification and surface disinfection in various scenarios such as homes, medical facilities, and transportation. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a bar chart comparing the disinfection effects of the disinfectant in the embodiments and comparative examples of the present invention; Figure 2 This is a bar chart comparing the sterilization rates of the disinfectant in the present invention with those of comparative examples; Figure 3 This is a bar chart comparing the sustained-release effects of the disinfectant in the embodiments and comparative examples of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0024] Example 1: Preparation of a green tea extract, comprising the following steps: Add 1000g of green tea powder to 15000g of deionized water, mix well, add citric acid, adjust the pH to 4.0-5.0, heat to 75℃, extract for 40min, after extraction is complete, cool to 20℃, filter with 200 mesh nylon cloth, filter with 0.45μm suction filter, and distill under reduced pressure to obtain green tea extract.

[0025] Example 2: Preparation of a green tea extract, comprising the following steps: Add 1000g of green tea powder to 18000g of deionized water, mix well, add citric acid, adjust the pH to 4.0-5.0, heat to 80℃, extract for 30min, after extraction is complete, cool to 25℃, filter with 200 mesh nylon cloth, filter with 0.45μm suction filter, and distill under reduced pressure to obtain green tea extract.

[0026] Example 3: Preparation of a green tea extract, comprising the following steps: Add 1000g of green tea powder to 20000g of deionized water, mix well, add citric acid, adjust the pH to 4.0-5.0, heat to 85℃, extract for 20min, after extraction is complete, cool to 30℃, filter with 200 mesh nylon cloth, filter with 0.45μm suction filter, and distill under reduced pressure to obtain green tea extract.

[0027] Example 4: Preparation of a nanoemulsion concentrate, comprising the following steps: S1: Add 18g of green tea extract (Example 1) and 10g of citric acid to 580g of deionized water, heat to 35°C, stir for 25min, and dissolve completely to obtain an aqueous phase; S2: Add 10g of vitamin E and 60g of Tween-80 to 100g of cedar oil, heat to 20℃, stir for 5 minutes, and the mixture is complete to obtain the oil phase; S3: Add 140g of aqueous phase and 10g of oil phase to a high-speed shear mill, heat to 40℃, rotate at 10000rpm, and shear at high speed for 8min. Transfer to a high-pressure homogenizer, pressurize to 65MPa for 1min for the first time, pressurize to 85MPa for 1min for the second time, and pressurize to 105MPa for 1min for the third time. Homogenization is complete. D90 < 200nm, and nanoemulsion concentrate is obtained.

[0028] Example 5: Preparation of a nanoemulsion concentrate, comprising the following steps: S1: Add 20g of green tea extract (Example 2) and 10g of citric acid to 600g of deionized water, heat to 40°C, stir for 20min, and dissolve completely to obtain the aqueous phase; S2: Add 20g of vitamin E and 80g of Tween-80 to 100g of cedar oil, heat to 25℃, stir for 4 minutes, and the mixture is complete to obtain the oil phase; S3: Add 150g of aqueous phase and 10g of oil phase to a high-speed shear mill, heat to 45℃, rotate at 9000rpm, and shear at high speed for 10min. Transfer to a high-pressure homogenizer, pressurize to 60MPa for 2min, pressurize to 80MPa for 2min, pressurize to 100MPa for 2min, and homogenize to complete the homogenization. D90 < 200nm, and obtain nanoemulsion concentrate.

[0029] Example 6: Preparation of a nanoemulsion concentrate, comprising the following steps: S1: Add 22g of green tea extract (Example 3) and 10g of citric acid to 620g of deionized water, heat to 45°C, stir for 15min, and dissolve completely to obtain the aqueous phase; S2: Add 30g of vitamin E and 100g of Tween-80 to 100g of cedar oil, heat to 30℃, stir for 3 minutes, and the mixture is complete to obtain the oil phase; S3: Add 160g of aqueous phase and 10g of oil phase to a high-speed shear mill, heat to 50℃, rotate at 8000rpm, and shear at high speed for 12min. Transfer to a high-pressure homogenizer, pressurize to 55MPa for 3min for the first time, pressurize to 75MPa for 3min for the second time, pressurize to 95MPa for 3min for the third time, and homogenize to complete the homogenization. D90 < 200nm, and obtain nanoemulsion concentrate.

[0030] Example 7: Preparation of a broad-spectrum antibacterial disinfectant for air made from green tea extract, comprising the following steps: S1: Add 20g of suspending agent sugar to 100g of carrageenan, stir and mix for 3 minutes, add 2400g of deionized water, stir for 8 minutes at 300 rpm, heat to 85℃ at 400 rpm, stir for 25 minutes to obtain carrageenan solution. S2: Add 80g of nanoemulsion concentrate (Example 4) to carrageenan solution, heat to 50°C, stir at 300 rpm for 2 min, then stir at 450 rpm for 10 min to obtain a broad-spectrum antibacterial disinfectant for air.

[0031] Example 8: Preparation of a broad-spectrum antibacterial disinfectant for air made from green tea extract, comprising the following steps: S1: Add 30g of suspending agent sugar to 100g of carrageenan, stir and mix for 5 minutes, add 2500g of deionized water, stir for 7 minutes at 350 rpm, heat to 80℃, stir at 450 rpm for 20 minutes to obtain carrageenan solution. S2: Add 100g of nanoemulsion concentrate (Example 5) to 100g of carrageenan solution, heat to 55°C, stir at 250 rpm for 3 min, then stir at 400 rpm for 13 min to obtain a broad-spectrum antibacterial disinfectant for air.

[0032] Example 9: Preparation of a broad-spectrum antibacterial disinfectant for air made from green tea extract, comprising the following steps: S1: Add 50g of suspending agent sugar to 100g of carrageenan, stir and mix for 7 minutes, add 2600g of deionized water, stir for 6 minutes at 400 rpm, heat to 75℃, stir at 500 rpm for 15 minutes to obtain carrageenan solution. S2: Add 120g of nanoemulsion concentrate (Example 6) to 100g of carrageenan solution, heat to 60°C, stir at 200 rpm for 4 min, then stir at 350 rpm for 15 min to obtain a broad-spectrum antibacterial disinfectant for air.

[0033] Example 10: Preparation of a broad-spectrum antibacterial disinfectant for air made from green tea extract, comprising the following steps: S1: Add 20g of suspending agent sugar to 100g of carrageenan, stir and mix for 3 minutes, add 2400g of deionized water, stir for 8 minutes at 300 rpm, add 5g of carboxymethyl chitosan, heat to 85℃, stir at 400 rpm for 25 minutes to obtain carrageenan solution. S2: Add 80g of nanoemulsion concentrate (Example 4) to carrageenan solution, heat to 50°C, stir at 300 rpm for 2 min, then stir at 450 rpm for 10 min to obtain a broad-spectrum antibacterial disinfectant for air.

[0034] Example 11: Preparation of a broad-spectrum antibacterial disinfectant for air made from green tea extract, comprising the following steps: S1: Add 20g of suspending agent sugar to 100g of carrageenan, stir and mix for 3 minutes, add 2400g of deionized water, stir for 8 minutes at 300 rpm, heat to 85℃ at 400 rpm, stir for 25 minutes to obtain carrageenan solution. S2: Add 80g of nanoemulsion concentrate (Example 4), 1g of zinc lactate and 2g of polylysine to carrageenan solution, heat to 50°C, stir at 300 rpm for 2 min, stir at 450 rpm for 10 min to obtain a broad-spectrum antibacterial disinfectant for air.

[0035] Comparative Example 1: Compared with Example 7, this comparative example did not add citric acid in the preparation process of the nanoemulsion concentrate. All other steps and parameters were the same, and will not be repeated here. The final result was a broad-spectrum antibacterial disinfectant for air.

[0036] Comparative Example 2: This comparative example differs from Example 7 only in that "carrageenan" is replaced with "sodium carboxymethyl cellulose". All other steps and parameters are the same, and will not be repeated here. The final result is a broad-spectrum antibacterial disinfectant for air.

[0037] Comparative Example 3: Compared with Example 7, this comparative example did not use a high-pressure homogenizer in the preparation process of the nanoemulsion concentrate; it only performed high-speed shearing. The remaining steps and parameters were the same, and will not be repeated here. The final product was a broad-spectrum antibacterial disinfectant for air.

[0038] Performance testing: Air disinfection effect test: In accordance with the GB 27948-2020 testing standard, an aerosol generator and an air microbial sampler were used, and the test species was Staphylococcus albus. 1. Add the white glucose bacterial solution to the aerosol generator, place it in a constant temperature and humidity chamber, and atomize until the bacterial concentration in the air reaches 5×10⁻⁶. 4 CFU / m 3 -5×10 5 CFU / m 3 Let stand for 5 minutes, then take a sample to serve as the control group before disinfection; 2. Take 10 mL of each of the disinfectants from Examples 7-11 and Comparative Examples 1-3, add them to a sprayer, place them in the constant temperature and humidity chamber described above, and continue for 2 hours to collect air samples. 3. Place the sampled plates in an incubator, heat to 37℃, incubate for 48 hours, and count the number of colonies; 4. Sterilization rate calculation: Surface disinfection effect test: According to the GB 27947-2020 testing standard, a constant temperature incubator was used, and the test strains were Staphylococcus aureus and Escherichia coli; 1. Take 0.9 mL of each of the disinfectants from Examples 7-11 and Comparative Examples 1-3, add 0.1 mL of bacterial suspension, place in a shaker, heat to 20-30℃, shake for 10 min, take 0.5 mL of sample, add 4.5 mL of neutralizing agent, mix well, neutralize for 10 min, take 0.5 mL of sample, add to an inoculation plate, place in a constant temperature incubator, heat to 37℃, incubate for 48 h, and count the number of colonies; 2. Calculation formula: N0 represents the bacterial count before disinfection, and N1 represents the bacterial count after disinfection. Table 1. Detection data results of the examples and comparative examples Stability test: The test was conducted using high performance liquid chromatography (HPLC) in accordance with the testing standards of the General Chapter (9001) of Part IV of the 2020 edition of the Pharmacopoeia of the People's Republic of China. 1. Take 10 mL of each of the disinfectants from Examples 7-11 and Comparative Examples 1-3, place them in a constant temperature incubator, heat to 40℃±2℃, relative humidity 75%±5%, and leave for 30 days; 2. Remove the sample and observe whether there are phenomena such as layering, demulsification, or mold growth. Take another sample and use HPLC to detect the content of gallic catechin gallate (EGCG). 3. Calculation formula: .

[0039] Sustained-release performance test: According to the GB / T 18801-2015 testing standard, gas chromatography-mass spectrometry was used. Take 100 mL each of the disinfectants from Examples 7-11 and Comparative Examples 1-3, place them in the center of a sealed room, and leave them for 7 days. On days 1, 3, and 7, collect air samples using an air sampler, and analyze the concentration of cedrol in the air (μg / mL) using GC-MS. 3 ).

[0040] Table 2. Test data results of the examples and comparative examples Data Analysis: As can be seen from Tables 1-2, the green tea extract air broad-spectrum antibacterial disinfectant prepared by the present invention has better antibacterial effect, stability and sustained release properties. Comparative Example 1, lacking citric acid, exhibited a sterilization rate of only 85.34%, a EGCG retention rate as low as 68.3%, and slight layering and color darkening. The root cause lies in the absence of the multiple synergistic effects of citric acid. Citric acid not only creates an acidic environment to disrupt microbial cell membranes but also synergistically enhances antibacterial efficiency with catechins. Furthermore, the acidic environment effectively inhibits the oxidative degradation of catechins, particularly EGCG, while regulating the system's pH helps maintain the emulsion's physical stability. In addition, the lack of a pH buffer system leads to decreased compatibility between components, resulting in slight layering and color darkening due to component degradation. Comparative Example 2, due to the use of sodium carboxymethyl cellulose instead of carrageenan, resulted in a decrease in its bactericidal rate to 92.15%, and the cedrol concentration was only 5.8 μg / m³ on day 7. 3 The results were significantly lower than those in the examples, and the samples showed surface shrinkage and uneven texture. The root cause is that although sodium carboxymethyl cellulose can provide a certain thickening effect, it cannot form a stable and dense three-dimensional gel network structure like carrageenan. This greatly weakens the controlled release ability of the active ingredients, and the nanoemulsion cannot be effectively fixed and protected in the system. In addition, the material has poor film-forming and water-retention properties, which makes the water easy to evaporate and destroys the integrity of the dosage form. This not only affects the uniform release of the active ingredients, but also directly weakens the product's long-lasting antibacterial ability and physical stability. Comparative Example 3, due to the lack of high-pressure homogenization and reliance solely on high-speed shearing to prepare the emulsion, resulted in a significant decrease in its sterilization rate to 90.21% and a substantial drop in EGCG retention to 71.5%. Furthermore, the sample exhibited severe stratification and a large amount of precipitation. The fundamental reason for this is that high-speed shearing can only form micron-sized coarse emulsions with large and unevenly distributed droplet sizes. The system has high surface energy, poor thermodynamic stability, and is prone to aging and gravity sedimentation. At the same time, the large droplet size leads to poor dispersion of active ingredients (catechins, cedar oil, etc.) in the system, resulting in insufficient effective contact area and directly affecting its antibacterial efficiency. In addition, the large oil-water interface area greatly increases the opportunity for sensitive ingredients such as catechins to come into contact with oxygen, accelerating their oxidative degradation chain reaction and causing rapid inactivation of the core active substances. Ultimately, this manifests as a significant deterioration in both product stability and efficacy. Example 10, by introducing carboxymethyl chitosan, significantly improved the overall performance of the product, achieving a sterilization rate of 99.55%, an EGCG retention rate of 93.2%, and a cedrol concentration of 17.2 μg / m³ on day 7. 3 All of these are superior to the basic embodiment, and the physical state remains stable without change. This is due to the interpenetrating polymer network formed by carboxymethyl chitosan and carrageenan, which enhances the density and stability of the gel structure, thereby more effectively protecting the active ingredients and delaying their release. In addition, the film-forming properties and slight antibacterial properties of carboxymethyl chitosan itself also synergistically enhance the physical barrier function and antibacterial effect. Example 11, through the combination of zinc lactate and polylysine, achieved a remarkable synergistic effect, with a bactericidal rate of 99.60% and a logarithmic kill value of 4.70, both the highest among all examples. Simultaneously, the EGCG retention rate was 94.5% and the sustained-release concentration was 18.5 μg / m³. 3 It also performed best because the antibacterial effect of the metal ions provided by zinc lactate and the membrane disruption mechanism of polylysine formed a multi-target synergistic attack with the original natural antibacterial system, which significantly improved the antibacterial efficiency. In addition, as a cationic polypeptide, polylysine can bind to negatively charged catechins, emulsion droplets and other substances through electrostatic interactions, which further stabilized the system structure and contributed to its excellent overall performance.

[0041] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

[0042] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. Preparation of a broad-spectrum antibacterial disinfectant for air made from green tea extract, characterized in that, The preparation steps are as follows: Step S1: Add the suspending agent sugar to the carrageenan and stir for 3-7 minutes. Add deionized water and stir for 6-8 minutes. Heat to 75-85℃, increase the speed, and stir for 15-25 minutes to obtain the carrageenan solution. Step S2: Add the nanoemulsion concentrate to the carrageenan solution, heat to 50-60℃, stir for 2-4 minutes, increase the speed, and stir for 10-15 minutes to obtain a broad-spectrum antibacterial disinfectant for air.

2. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 1, characterized in that, The mass ratio of the suspending agent, carrageenan, and deionized water in step S1 is 0.2-0.5:1:24-26.

3. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 1, characterized in that, The mass ratio of the nanoemulsion concentrate to the carrageenan solution in step S2 is 0.8-1.2:

1.

4. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 1, characterized in that, The preparation steps of the nanoemulsion concentrate in step S2 are as follows: Step A1: Add green tea extract and citric acid to deionized water, heat to 35-45℃, stir for 15-25 minutes until dissolved, and obtain the aqueous phase; Step A2: Add vitamin E and Tween-80 to cedar oil, heat to 20-30℃, stir for 3-5 minutes, and the mixture is complete to obtain the oil phase; Step A3: Add the aqueous phase and oil phase to a high-speed shear mill, heat to 40-50℃, and shear at high speed for 8-12 minutes. Transfer to a high-pressure homogenizer, apply gradient pressure of 60-100MPa for 6-9 minutes until homogenization is complete. D90 < 200nm, and obtain a nanoemulsion concentrate.

5. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 4, characterized in that, The mass ratio of green tea extract, citric acid and deionized water in step A1 is 1.8-2.2:1:58-62.

6. The preparation method of a green tea extract broad-spectrum antibacterial disinfectant for air according to claim 4, characterized in that, The mass ratio of vitamin E, Tween-80 and cedar oil mentioned in step A2 is 0.1-0.3:0.6-1:

1.

7. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 4, characterized in that, The mass ratio of the aqueous phase to the oil phase in step A3 is 14-16:

1.

8. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 4, characterized in that, The preparation steps of the green tea extract described in step A1 are as follows: Add green tea powder to deionized water, mix well, add citric acid, adjust pH to 4.0-5.0, heat to 75-85℃, extract for 20-40 minutes, after extraction is complete, cool to 20-30℃, filter with 200 mesh nylon cloth, filter with 0.45μm suction filter, and distill under reduced pressure to obtain green tea extract.

9. The preparation method of a broad-spectrum antibacterial disinfectant for air containing green tea extract according to claim 8, characterized in that, The mass ratio of green tea powder to deionized water is 1:15-20.

10. The application of a green tea extract air broad-spectrum antibacterial disinfectant according to any one of claims 1-9, characterized in that, The disinfectant is mainly used for air purification in spaces, auxiliary infection control in medical and health institutions, maintenance of the internal environment of vehicles, disinfection and deodorization of places with special odors, and internal disinfection of personal items.

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