Preparation method of selenium-zinc oxide nanocomposite antibacterial and antioxidant material using Sophora japonica extract
The one-step in situ synthesis of selenium-zinc oxide nanocomposite materials using Sophora japonica extract solves the environmental risks and large-scale production problems of traditional methods, achieves efficient and safe antibacterial and antioxidant properties, and is suitable for healthy animal breeding.
Patent Information
- Application Number
- CN202310059339.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-01-18
- Publication Date
- 2025-09-12
- Estimated Expiration
- 2043-01-18
AI Technical Summary
Existing technologies make it difficult to prepare selenium-zinc oxide nanocomposites efficiently and safely, and traditional chemical synthesis methods have environmental risks and chemical reagent residue problems. There are no reports on the synthesis of selenium-zinc oxide nanocomposites using Sophora japonica extracts by biosynthesis.
Selenium-zinc oxide nanocomposite materials were prepared by a one-step in-situ synthesis method using Sophora japonica extract as a reducing agent and stabilizer. The active ingredients in Sophora japonica, such as flavonoids and saponin compounds, reacted with metal ions to achieve stabilization and doping of nanoparticles. The preparation process is green and environmentally friendly and easy to scale up.
The prepared selenium-zinc oxide nanocomposite material has excellent antibacterial and antioxidant activities, is safe and efficient, and is suitable for healthy animal breeding.
Smart Images
Figure CN116510030B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the fields of nano material preparation technology and animal health breeding, and particularly relates to a preparation method of a selenium-zinc oxide nano-composite antibacterial and antioxidant material prepared from a sophora japonica flower extract. Background Art
[0002] Zinc and selenium play a very important role in the growth of animals and plants and human health. For animal health breeding, zinc and selenium, as trace elements, participate in various physiological functions in livestock and poultry, such as antioxidant, material metabolism, growth and development, and play an important role in maintaining the intestinal barrier and intestinal health (Animal Husbandry and Feed Science. 2020, 41(02): 9-12; Chinese Journal of Animal Husbandry. 2021, 57(11): 51-55). In addition, selenium and zinc both have antibacterial activity and can effectively kill pathogens, and have the potential to develop alternative products to antibiotics. However, high concentrations of selenium and zinc can cause serious toxic reactions (Toxicol. Sci. 2008, 101(1): 22-31; Journal of Animal Nutrition. 2022, 34: 818-822). In particular, long-term feeding of high-dose zinc oxide can cause serious harm to the soil and water environment. Therefore, improving the biological activity and effective utilization of selenium and zinc and reducing their dosage are the keys to their application in the field of animal health breeding.
[0003] Selenium is a typical nutrient that binds to zinc oxide. Doping with selenium can optimize the electronic structure and surface characteristics of zinc oxide. As a p-type semiconductor with a narrow bandgap, selenium's 2p orbital contribution leads to the generation of mixed or localized states near the top of the valence band, narrowing the bandgap and inducing a plasmon effect in the visible light range, thereby enhancing the antibacterial activity of zinc oxide-based materials (Semicond. Sci. Tech. 2015, 30:125003). Furthermore, the combination with zinc oxide creates more oxygen vacancies, increasing surface activity and enriching the material with reactive oxygen species, leading to greater toxicity to bacteria (Opt. Mater. 2020, 107:110122). Furthermore, the active surface electrons of the composite can pair with lone pairs of free radicals, neutralizing them and imparting antioxidant activity (J. Environ. Chem. Eng. 2021, 9:105481).
[0004] Nano-sizing of metal and metal oxide materials is an effective strategy to enhance their antimicrobial activity and bioavailability. However, the main challenge facing nano-sizing is the preparation technology. How to avoid the agglomeration of nanoparticles to form small-sized nanoparticles and the clean and environmentally friendly preparation methods are the current research focuses. Traditional chemical synthesis methods usually require the addition of additional chemical capping agents to control the particle size and morphology, which not only brings greater environmental risks, but also the residual chemical reagents make the products produce greater chemical toxicity, which is not suitable for the production of antimicrobial materials with high safety requirements. Biosynthesis is a green method for preparing metals and metal oxides that has attracted much attention in recent years. Studies have shown that plant-mediated biosynthesis is not only clean and environmentally friendly, but also simple to operate, low-cost, and easier to scale up. More importantly, plant extracts contain a variety of active ingredients, which have advantages for the preparation of more complex composite systems. They can effectively simplify the synthesis process and realize the one-step in-situ synthesis of composite materials. Sophora japonica is the dried flower buds of the leguminous plant Sophora japonica, which has significant pharmacological effects. The main chemical components of Sophora japonica are flavonoids (including rutin, dendrobium, kaempferol, and sophora japonica amine), saponins, and fatty acids. In addition, it also contains polysaccharides, proteins, amino acids, and other components. It has the potential mechanism and feasibility of reducing and preparing nano-selenium and zinc oxide (Journal of Practical Traditional Chinese Medicine. 2021, 37(12): 2141-2143). However, there are currently no reports on the synthesis of selenium-zinc oxide nanocomposites from Sophora japonica extracts. Summary of the Invention
[0005] The present invention provides a method for preparing a selenium-zinc oxide nanocomposite antibacterial and antioxidant material from Sophora japonica extract. This method fully utilizes the abundant active ingredients in Sophora japonica to achieve a one-step in-situ synthesis of the selenium-zinc oxide nanocomposite. The preparation process is environmentally friendly, simple, and amenable to large-scale production. The product is safe and efficient, exhibits excellent antibacterial and antioxidant activities, and is suitable for healthy animal husbandry.
[0006] 1. Preparation and structure of selenium-zinc oxide nanocomposites
[0007] The invention provides a preparation method of a selenium-zinc oxide nano-composite antibacterial and antioxidant material from a sophora japonica seed extract. The method comprises the following steps: washing dried sophora japonica seeds, soaking the dried sophora japonica seeds in water for 0.5-1 hour, extracting the dried sophora japonica seeds in a water bath at 60-70°C for 1-2 hours, and filtering the dried sophora japonica seeds extract to obtain a sophora japonica seed extract; adding zinc salt and sodium selenite to the sophora japonica seed extract, stirring the mixture at 300-500 rpm in a constant temperature oil bath for reaction, centrifuging the obtained product at 8000-12000 rpm for three times, and drying the obtained product in an oven at 60-95°C for 10-24 hours to obtain the selenium-zinc oxide nano-composite material.
[0008] The solid-to-liquid ratio (g / mL) of the dried Sophora japonica seeds to water is 1:10-1:40.
[0009] The zinc salt is at least one of zinc nitrate hexahydrate and zinc acetate dihydrate, and the concentration of the zinc salt solution is 0.01 to 0.1 mol / L. The molar ratio of sodium selenite to zinc ion is 1:1 to 1:4. The constant temperature oil bath temperature is 55 to 80°C, and the reaction time is 2 to 5 hours. The drying step is performed in an oven at 60 to 95°C for 10 to 24 hours.
[0010] The synthesis mechanism of the present invention is as follows: Sophora japonica extract contains flavonoids such as rutin, quercetin, and kaempferol, as well as saponins, and small amounts of polysaccharides, proteins, and amino acids. The flavonoids and saponins react with metal ions to reduce them to elemental selenium and zero-valent zinc, which can then be further oxidized to zinc oxide by dissolved oxygen in the reaction solution. Some of the flavonoid conversion products, polysaccharides, and proteins readily bind to highly surface-active nanoparticles, stabilizing the nanoparticles and ultimately yielding a small-sized selenium-zinc oxide composite nanocomposite.
[0011] Figure 1 The XRD spectrum of the selenium-zinc oxide nanocomposite prepared in the present invention shows diffraction peaks of wurtzite-structured zinc oxide and crystalline selenium, indicating that the selenium-zinc oxide composite material has been successfully prepared. Figure 2 The TEM image of the selenium-zinc oxide nanocomposite prepared in the present invention shows that the selenium-zinc oxide composite material is a spherical structure less than 50 nm, and nano-selenium and zinc oxide are in a doped state. Figure 3 This is the infrared spectrum of selenium-zinc oxide nanocomposite material, 1430cm -1 and 1658cm -1 The absorption peak at 723 cm indicates the formation of zinc oxide. -1 The absorption peak at 2925 cm indicates the formation of red nano-selenium. -1 and 1656cm -1 and 1058cm -1 The absorption peaks between 878cm indicate the presence of methyl, methylene, carbonyl, benzene ring, amino and hydroxyl groups, indicating that the extract of Sophora japonica contains rutin, quercetin, triterpenoid saponins, proteins and amino acids. -1 and 805cm -1 The glycosidic bond absorption peaks at 1430 cm indicate the presence of polysaccharides. These absorption peaks are reflected in the spectrum of selenium-zinc oxide composite materials, such as 1430 cm -1 The absorption peak at indicates that proteins and amino acids are involved in the stabilization of nanoparticles, and the shift of the relevant peaks indicates that rutin and saponins are involved in the reduction of metal ions.
[0012] 2. Properties of Selenium-ZnO Nanocomposites
[0013] The antibacterial properties of the selenium-zinc oxide nanocomposites prepared in the embodiment were evaluated by testing the minimum inhibitory concentration (MIC) using the microbroth dilution method. The test method was as follows: 1) Preparation of the test bacteria: a single colony was picked from a MH agar plate cultured overnight at 37°C using an inoculating loop and placed in sterile water to prepare a 0.5 McFarland turbidity standard (10 8 CFU / mL) of bacterial suspension was diluted to 10 6 CFU / mL; 2) Prepare a 2 mg / mL sample suspension and add 0.2 mL to the first well of a 96-well plate. Add 0.1 mL of MH broth to wells 2 through 9 of the 96-well plate. Then, pipette 0.1 mg / mL of the suspension starting from the first well and add it to the following wells. After dilution, add 0.1 mg / mL of the bacterial suspension to each well. At this point, the volume per well is 0.2 mL. The drug concentrations in wells 1 through 9 are 1, 0.5, 0.25, 0.125, 0.0625, 0.03125, 0.015625, 0.0078125, and 0.00390625 mg / mL, respectively. Add 0.1 mL of the bacterial suspension to 0.1 mL of MH broth as a positive control. To eliminate interference from sample color, a negative control containing the same concentration of the sample solution as the experimental group was prepared without the bacterial suspension. This experiment was repeated in triplicate. The lowest drug concentration that completely inhibited bacterial growth in the well was defined as the MIC. The antibacterial performance evaluation results of the selenium-zinc oxide nanocomposites in Examples 1-5 are shown in Table 1, which shows that the selenium-zinc oxide nanocomposites prepared by the present invention have high antibacterial activity against Escherichia coli and Staphylococcus aureus, and the inhibitory activity against Staphylococcus aureus is better than that against Escherichia coli.
[0014] Table 1 MIC (mg / mL) of selenium-zinc oxide nanocomposites against Escherichia coli and Staphylococcus aureus in Examples 1-5
[0015]
[0016] The antioxidant properties of the selenium-zinc oxide nanocomposite prepared in the examples were evaluated by testing its scavenging rate of hydroxyl and DPPH free radicals. The testing method is as follows:
[0017] (1) Hydroxyl radical scavenging rate: 1 mL of 6 mmol / L ferric sulfate heptahydrate, 1 mL of 9 mmol / L salicylic acid ethanol solution, and 1 mL of samples of different concentrations (0.1-5 mg / mL) were added to a 10 mL test tube. 0.1 mL of hydrogen peroxide (0.3%) and 1 mL of ultrapure water were then added to initiate the reaction. The test tube was then placed in a 37°C water bath for 30 min, and the absorbance was measured at 510 nm. Ultrapure water was used instead of the sample as the blank group, and 0.1 mL of ultrapure water was used instead of H2O2 as the control group. Figure 4The selenium-zinc oxide nanocomposite prepared by the present invention
[0018] The composite antibacterial and antioxidant material has a high hydroxyl radical scavenging ability, and its IC 50 It can reach 0.2mg / mL.
[0019] (2) DPPH free radical scavenging rate: Take 1 mL of sample ethanol solution with different concentrations (0.1~5 mg / mL) and 4 mL of 0.1 mmol / L
[0020] The mixture was mixed with DPPH solution and placed in a 30°C water bath in the dark for 30 minutes, and then the absorbance was measured at 517 nm. 1 mL of ethanol was used instead of the sample as a blank group, and 4 mL of ethanol was used instead of DPPH as a control group. Figure 5 This shows that the selenium-zinc oxide nanocomposite antibacterial and antioxidant material prepared by the present invention has a good scavenging ability against DPPH, and its IC 50 It can reach 0.45mg / mL.
[0021] In summary, the present invention uses Sophora japonica extract to synthesize selenium-zinc oxide nanocomposite antibacterial and antioxidant materials with the following advantages:
[0022] 1. By doping zinc oxide with nano-selenium, the biological activity and safety of metal nanomaterials are improved.
[0023] 2. Using Sophora japonica extract as a reducing agent and stabilizer, a one-step in situ synthesis of selenium-zinc oxide nanocomposite materials is achieved. The preparation process is clean and environmentally friendly, the process is simple, and it is easy to produce on a large scale. The obtained nanocomposite materials are safe, highly active, and have excellent broad-spectrum antibacterial and antioxidant activities. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 This is the XRD spectrum of the selenium-zinc oxide nanocomposite antibacterial and antioxidant material prepared in Example 2 of the present invention;
[0025] Figure 2 TEM spectrum of the selenium-zinc oxide nanocomposite antibacterial and antioxidant material prepared in Example 2 of the present invention;
[0026] Figure 3 This is the FTIR spectrum of the selenium-zinc oxide nanocomposite antibacterial and antioxidant material prepared in Example 2 of the present invention;
[0027] Figure 4 The scavenging rate of hydroxyl radicals at different concentrations of the selenium-zinc oxide nanocomposite antibacterial and antioxidant material prepared in Example 4 of the present invention;
[0028] Figure 5The scavenging rate of DPPH free radicals at different concentrations of the selenium-zinc oxide nanocomposite antibacterial and antioxidant material prepared in Example 4 of the present invention. DETAILED DESCRIPTION
[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with specific embodiments.
[0030] Example 1:
[0031] 2.5 g of dried Sophora japonica seeds were weighed and cleaned, then soaked in 100 mL of water for 1 h, extracted in a water bath at 60°C for 1 h, and filtered to obtain the Sophora japonica seed extract; 0.297 g of zinc nitrate hexahydrate and 0.173 g of sodium selenite were added to 100 mL of the Sophora japonica seed extract, stirred to dissolve, and then stirred at 300 rpm in a constant temperature oil bath at 55°C for 2 h. The resulting product was centrifuged and washed three times at 9000 rpm, and placed in an oven at 60°C for 24 h to obtain a selenium-zinc oxide nanocomposite material.
[0032] Example 2:
[0033] 4 g of dried Sophora japonica seeds were cleaned, soaked in 100 mL of water for 0.5 h, extracted in a 70 ° C water bath for 1 h, and filtered to obtain the Sophora japonica seeds extract; 1.485 g of zinc nitrate hexahydrate and 0.87 g of sodium selenite were added to 100 mL of Sophora japonica seeds extract, stirred to dissolve, and then heated in a 60 ° C constant temperature oil bath for 1 h.
[0034] The reaction was stirred at 500 rpm for 3 h, and the obtained product was centrifuged and washed three times at 8000 rpm, and then dried in an oven at 70° C. for 20 h to obtain a selenium-zinc oxide nanocomposite material.
[0035] Example 3:
[0036] 6 g of dried Sophora japonica seeds were cleaned, soaked in 100 mL of water for 1 h, extracted in a 60°C water bath for 2 h, and filtered to obtain the Sophora japonica seed extract; 2.97 g of zinc nitrate hexahydrate and 0.58 g of sodium selenite were added to 100 mL of the Sophora japonica seed extract, stirred to dissolve, and then stirred at 400 rpm in an 80°C constant temperature oil bath for 5 h. The resulting product was centrifuged and washed three times at 10,000 rpm, and dried in an oven at 80°C for 15 h to obtain a selenium-zinc oxide nanocomposite material.
[0037] Example 4:
[0038] 8 g of dried Sophora japonica seeds were cleaned, soaked in 100 mL of water for 0.5 h, extracted in a 60°C water bath for 1.5 h, and filtered to obtain the Sophora japonica seed extract; 1.1 g of zinc acetate dihydrate and 0.43 g of sodium selenite were added to 100 mL of the Sophora japonica seed extract, stirred to dissolve, and then stirred at 300 rpm in a 60°C constant temperature oil bath for 3 h. The resulting product was centrifuged and washed three times at 8000 rpm, and dried in an oven at 95°C for 10 h to obtain a selenium-zinc oxide nanocomposite material.
[0039] Example 5:
[0040] 10 g of dried Sophora japonica seeds were cleaned, soaked in 100 mL of water for 1 h, extracted in a 70°C water bath for 1 h, and filtered to obtain the Sophora japonica seed extract; 2.2 g of zinc acetate dihydrate and 0.43 g of sodium selenite were added to 100 mL of the Sophora japonica seed extract, stirred to dissolve, and then stirred at 500 rpm in a 70°C constant temperature oil bath for 4 h. The resulting product was centrifuged and washed three times at 12,000 rpm, and dried in an oven at 80°C for 15 h to obtain a selenium-zinc oxide nanocomposite material.
Claims
1. A method for preparing a selenium-zinc oxide nanocomposite antibacterial and antioxidant material from a sophora japonica seed extract, comprising: washing dried sophora japonica seeds, soaking them in water for 0.5 to 1 hour, extracting them in a water bath at 60 to 70° C. for 1 to 2 hours, and filtering them to obtain a sophora japonica seed extract; adding zinc salt and sodium selenite to the sophora japonica seed extract, stirring and reacting them in an oil bath at 55 to 80° C. for 2 to 5 hours, centrifuging and washing the resulting product, and drying it to obtain a selenium-zinc oxide nanocomposite material; The concentration of the zinc salt solution is 0.01-0.1 mol / L; the molar ratio of the sodium selenite to the zinc ion is 1:1-1:4; and the solid-liquid ratio of the dried sophora japonica seeds to water is 1:10-1:
40.
2. The method for preparing a selenium-zinc oxide nanocomposite antibacterial and antioxidant material from a sophora japonica extract according to claim 1, characterized in that: The zinc salt is at least one of zinc nitrate hexahydrate and zinc acetate dihydrate.
3. The method for preparing a selenium-zinc oxide nanocomposite antibacterial and antioxidant material from a sophora japonica extract according to claim 1, characterized in that: The stirring speed is 300-500 rpm.
4. The method for preparing a selenium-zinc oxide nanocomposite antibacterial and antioxidant material from a sophora japonica extract according to claim 1, characterized in that: The drying conditions of the selenium-zinc oxide nanocomposite material are: drying in an oven at 60-95° C. for 10-24 hours.