Platycladus orientalis essential oil microcapsule, and preparation method and application thereof
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- FUJIAN HUAFENG NEW MATERIALS
- Filing Date
- 2023-09-05
- Publication Date
- 2026-07-21
Smart Images
Figure CN117181141B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of microcapsule preparation technology, specifically relating to a cypress essential oil microcapsule, its preparation method, and its application. Background Technology
[0002] Chinese arborvitae (Platycladus orientalis) is widely distributed in my country's forest areas. Its wood is not only fragrant but also hard and has a unique grain, making it widely used in the manufacture of wooden furniture and ornaments. Furthermore, due to its strong cypress aroma, it is often used as a raw material for producing sachets, massage balls, and scented pillows, and can also be used in aromatherapy. The essential oil extracted from Chinese arborvitae contains natural terpene esters—methyl thujate. Its molecular formula has a heptagonal carbon ring structure, exhibiting excellent activity and possessing antiviral, cleansing, cell-protecting, infection-preventing, and tissue-regenerating functions. It is particularly effective in antibacterial properties; the antibacterial activity of Chinese arborvitae essential oil is more than five times that of tea tree essential oil, indicating broad development prospects in the food, pharmaceutical, hygiene, and textile industries.
[0003] However, the practical application effect of arborvitae essential oil is relatively low because it is a volatile essential oil with defects such as unstable composition and easy volatilization. To address this, Chinese invention patent application number 202310309943.1 discloses a method for preparing microcapsules of a sleep-aiding compound essential oil composition. The method involves sequentially adding an emulsifier and the sleep-aiding compound essential oil composition to a starch-saturated aqueous solution, homogenizing to obtain a stable emulsion; extruding the emulsion into isopropanol for dehydration, filtering, and obtaining a crude product of essential oil microcapsules; and then drying and grinding the crude microcapsule product to obtain the essential oil microcapsules. While essential oil microcapsules can prevent essential oil volatilization, the rupture of the microcapsules is unpredictable, and the release of essential oil usually occurs intermittently, resulting in the inability to maintain the efficacy of the essential oil in the final product application. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a slow-release arborvitae essential oil microcapsule, its preparation method and application.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for preparing arborvitae essential oil microcapsules, comprising the following steps:
[0006] S1: Dissolve non-crosslinked polystyrene in dichloromethane, then mix it with arborvitae essential oil to form an oil phase; disperse the resulting oil phase in a polyvinyl alcohol aqueous solution to react and construct an intermediate non-crosslinked polystyrene shell on the oil droplets of arborvitae essential oil;
[0007] S2: Add a composite solution containing gum arabic and gelatin to the product of S1 for emulsification, and then carry out a composite coagulation reaction and a solidification reaction in sequence to obtain arborvitae essential oil microcapsules.
[0008] Another technical solution adopted in this invention is: the arborvitae essential oil microcapsules prepared by the above-mentioned method for preparing arborvitae essential oil microcapsules.
[0009] Another technical solution adopted in this invention is the application of the above-mentioned arborvitae essential oil microcapsules on textiles.
[0010] The beneficial effects of this invention are as follows: The method for preparing arborvitae essential oil microcapsules provided by this invention constructs an intermediate non-crosslinked polystyrene shell on the oil droplets of arborvitae essential oil to provide an adhesive core structure, thereby preparing arborvitae essential oil microcapsules with extremely long-lasting release performance. Even after the microcapsules rupture, the essential oil can still have a slow release characteristic to obtain a lasting effect. Then, using a peach gum-gelatin solution as the wall material and selectively curing the microcapsules, the stability of the obtained arborvitae essential oil microcapsules is improved. Attached Figure Description
[0011] Figure 1 The results show the release rate of the powdered arborvitae essential oil microcapsules prepared in Examples 1-5 and the comparative examples during dialysis. Detailed Implementation
[0012] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.
[0013] A method for preparing arborvitae essential oil microcapsules includes the following steps:
[0014] S1: Dissolve non-crosslinked polystyrene in dichloromethane, then mix it with arborvitae essential oil to form an oil phase; disperse the resulting oil phase in a polyvinyl alcohol aqueous solution to react and construct an intermediate non-crosslinked polystyrene shell on the oil droplets of arborvitae essential oil;
[0015] S2: Add a composite solution containing gum arabic and gelatin to the product of S1 for emulsification, and then carry out a composite coagulation reaction and a solidification reaction in sequence to obtain arborvitae essential oil microcapsules.
[0016] As can be seen from the above description, the beneficial effects of the present invention are as follows: The method for preparing arborvitae essential oil microcapsules provided by the present invention involves constructing an intermediate non-crosslinked polystyrene shell on the oil droplets of arborvitae essential oil, and then preparing a gum-gelatin outer wall material. The arborvitae essential oil can dissolve the intermediate non-crosslinked polymer shell into a viscous core over time, increasing the viscosity of the arborvitae essential oil, so as to prepare arborvitae essential oil microcapsules with extremely long-lasting release performance. This allows the essential oil to still have slow release characteristics even after the microcapsules rupture, thus achieving a lasting effect. In particular, using a gum-gelatin solution as the wall material and selectively solidifying the microcapsules not only improves the stability of the obtained arborvitae essential oil microcapsules, but also, because gum has the effects of improving immunity, anti-tumor, scavenging free radicals, anti-aging, anti-infection, lowering blood lipids, and lowering blood sugar, it can endow the microcapsules with certain medicinal properties.
[0017] In preparing the oil phase, non-crosslinked polystyrene was first dissolved in dichloromethane to reduce the difficulty of mixing with arborvitae essential oil. The oil phase was then dispersed in an aqueous solution containing polyvinyl alcohol, where polyvinyl alcohol acts as a protective colloid, forming a protective film, reducing interfacial tension (improving the dispersion stability of the system), and increasing the viscosity of the system during the reaction.
[0018] Furthermore, the preparation method of non-crosslinked polystyrene is as follows: styrene and azobisisobutyronitrile are heated to 58-62°C and mixed to dissolve, obtaining a prepolymer solution. The prepolymer solution is stirred and reacted at 23-27°C for 28-32 minutes to obtain non-crosslinked polystyrene.
[0019] As described above, too low a temperature during dissolution will slow down the dissolution rate, while too high a temperature will accelerate the dissolution rate, easily leading to the formation of cross-linked styrene polymers. Therefore, controlling the dissolution temperature to 58–62°C is beneficial for styrene dissolution. During the prepolymer solution reaction, too high a temperature will increase the polymerization rate, causing the prepolymer to over-polymerize, or even directly forming cross-linked styrene polymers. Therefore, controlling the temperature to 23–27°C will allow the formation of non-cross-linked styrene polymers.
[0020] Furthermore, the reaction conditions for S1 are as follows: stirring at 23–27°C for 8–12 min, then heating to 42–48°C and holding for 0.8–1.2 h, followed by heating to 75–85°C and holding for 28–32 min.
[0021] As described above, dichloromethane is volatilized by heating and stirring to construct an intermediate non-crosslinked polystyrene shell on the arborvitae essential oil droplets, forming a viscous core structure.
[0022] Each stage of the heating process has a different function. Stirring at 23–27°C for 8–12 minutes is to ensure that the various substances are thoroughly and evenly mixed; raising the temperature to 42–48°C and holding it for 0.8–1.2 hours is the emulsification stage, which can form a stable oil-in-water emulsion; raising the temperature to 75–85°C and holding it for 28–32 minutes is to allow the dichloromethane to fully evaporate, leaving only arborvitae oil and non-crosslinked polystyrene in the core material.
[0023] Furthermore, the mass ratio of non-crosslinked polystyrene to dichloromethane in S1 is 1:11 to 3:8.
[0024] As can be seen from the above description, dichloromethane is used to dissolve non-crosslinked polystyrene, reducing the difficulty of dissolving it with essential oils.
[0025] Further, the mass ratio of peach gum to gelatin is 1:0.8 to 1:1.2. Preferably, the mass ratio of peach gum to gelatin is 1:1.
[0026] As described above, the yield initially increases and then decreases with the increase in the proportion of peach gum. The highest yield of composite aggregated microcapsules is achieved when the ratio of peach gum to gelatin is 1:1. As the proportion of peach gum continues to increase, the yield gradually decreases because fewer polymers are formed, and the core material cannot be well embedded in the wall material, resulting in the loss of the core material during the preparation process, thus reducing the yield.
[0027] Furthermore, the reaction conditions for the complex coagulation reaction are as follows: stirring at a temperature of 38–42°C, adjusting the pH to 4–4.5, and reacting for 28–32 minutes.
[0028] As described above, the isoelectric point of gelatin is approximately 4.7, and it exhibits its most stable state near this pH value. When the pH of the solution is below the isoelectric point, the gelatin displays a positive charge and readily combines with negatively charged ions in the solution to form a gel; conversely, when the pH of the solution is above the isoelectric point, the gelatin displays a negative charge, and its gel-forming ability is weaker. Therefore, during complex coagulation, the pH should be adjusted to 4–4.5.
[0029] Furthermore, the curing reaction conditions are as follows: stirring is carried out at a temperature of 13-17°C, the pH is adjusted to 5-8, transglutaminase is added to carry out the curing reaction, stirring is stopped after 2.3-2.7 hours, and the reaction continues for 10-13 hours.
[0030] As described above, transglutaminase catalyzes intramolecular and intermolecular covalent cross-linking of proteins and peptides, improving protein structure and function. Under typical non-enzymatic conditions, these proteins are difficult to break down, significantly enhancing the adhesive strength of gelatin and thus improving the stability of gum-gelatin composite wall materials. This enzyme exhibits high activity within a pH range of 5–8, with an optimal pH of 6.
[0031] Furthermore, the product obtained after the curing reaction is filtered, washed and precipitated to obtain wet capsules of microcapsules. The wet capsules of microcapsules are refrigerated overnight and then freeze-dried to obtain powdered arborvitae essential oil microcapsules.
[0032] As described above, the powdered arborvitae essential oil microcapsules obtained after purification and drying are more conducive to preservation and use. Pre-freezing the wet capsules overnight in cold storage allows the material to crystallize. If the product fails to freeze into a solid before vacuuming, under vacuum cooling, when the vacuum reaches a certain level, the air dissolved in the water will "boil" and bubble, causing the product to escape from the container. When the pressure drops below a certain value, the product will freeze into ice, but without a fixed shape, and the glass container may even crack, leading to freeze-drying failure.
[0033] Furthermore, the essential oil of Platycladus orientalis leaves was extracted using the supercritical CO2 method.
[0034] As can be seen from the above description, supercritical CO2 extraction can yield essential oils with better color, aroma, and purity.
[0035] Another technical solution adopted in this invention is: the arborvitae essential oil microcapsules prepared by the above-mentioned method for preparing arborvitae essential oil microcapsules.
[0036] As can be seen from the above description, after the arborvitae essential oil microcapsules rupture, the essential oil can be released slowly to achieve a lasting effect.
[0037] Another technical solution adopted in this invention is the application of the above-mentioned arborvitae essential oil microcapsules on textiles.
[0038] As can be seen from the above description, aromatic textiles treated with arborvitae oil microcapsules can be obtained by immersing the fabric in a finishing agent containing arborvitae essential oil microcapsules, then removing the fabric, spinning it dry, and baking and drying it.
[0039] Example 1 of the present invention is: a method for preparing arborvitae essential oil microcapsules, comprising the following steps:
[0040] S1: Fresh arborvitae seed pericarp waste was placed in a flask, and cellulase at a mass ratio of 1% was added. The mixture was then cultured in a water bath at a constant temperature of 50℃ for 2 hours. The mixture was then transferred to a microwave extraction device and microwaved at a power of 560W for 60 minutes. The distillate was continuously condensed using a cooling system outside the microwave cavity, and the condensate was refluxed back into the extraction container to obtain arborvitae essential oil. The obtained arborvitae essential oil was stored at 4℃ in the dark.
[0041] S2: 100g of styrene and 2g of azobisisobutyronitrile are heated to 60℃ and mixed and dissolved in a beaker to obtain a prepolymer solution. The prepolymer solution is poured into a polytetrafluoroethylene box and stirred and reacted at 25℃ for 30min to obtain non-crosslinked polystyrene.
[0042] S3: Dissolve 1.2g of non-crosslinked polystyrene in 8.4g of dichloromethane, and then mix it with 3.0g of arborvitae essential oil to form an oil phase; disperse the resulting oil phase in an aqueous solution containing 1.0wt% polyvinyl alcohol, stir at 25°C for 10min, then raise the temperature to 45°C and keep it at that temperature for 1h, and then raise the temperature to 80°C and keep it at that temperature for 30min to evaporate the solvent from the oil droplets, and construct an intermediate non-crosslinked polystyrene shell as a core material on the oil droplets of arborvitae essential oil;
[0043] S4: A composite solution of peach gum and gelatin in a 1:1 mass ratio (the mass ratio of solute to solvent in the composite solution is 1.25%, the solvent is water, and the solutes are peach gum and gelatin) is added as the wall material. The mass ratio of the core material to the wall material is 1:1. After emulsification using a high-speed dispersion homogenizer, the mixture is poured into a three-necked flask and stirred at 40°C. The pH is adjusted to 4.3 with acetic acid, and the reaction is allowed to proceed for 30 minutes for a composite coagulation reaction. The mixture is then stirred at 15°C, and the pH is adjusted to 6 with sodium hydroxide. Transglutaminase at a ratio of 25 u / g gelatin is added for a solidification reaction. After 2.5 hours of reaction, stirring is stopped, and the reaction continues for 12 hours for solidification. After the solidification reaction, the product is filtered, washed, and precipitated to obtain wet capsules of microcapsules. The wet capsules of microcapsules are refrigerated overnight and then freeze-dried to obtain powdered arborvitae essential oil microcapsules.
[0044] Embodiment 2 of the present invention is as follows:
[0045] The only difference between Example 2 and Example 1 is that the mass of non-crosslinked polystyrene in S3 is 1.5g and the mass of dichloromethane is 9.0g.
[0046] Embodiment 3 of the present invention is as follows:
[0047] The only difference between Example 3 and Example 1 is that the mass of non-crosslinked polystyrene in S3 is 1.8g and the mass of dichloromethane is 9.6g.
[0048] Embodiment 4 of the present invention is as follows:
[0049] The only difference between Example 4 and Example 1 is that the mass of non-crosslinked polystyrene in S3 is 2g and the mass of dichloromethane is 10g.
[0050] Embodiment 5 of the present invention is as follows:
[0051] The only difference between Example 5 and Example 1 is that the mass of non-crosslinked polystyrene in S3 is 2.1g and the mass of dichloromethane is 10.2g.
[0052] Example 6 of the present invention is: a method for preparing arborvitae essential oil microcapsules, comprising the following steps:
[0053] S1: Fresh arborvitae seed pericarp waste was placed in a flask, and cellulase at a mass ratio of 1% was added. The mixture was then cultured in a water bath at a constant temperature of 50℃ for 2 hours. The mixture was then transferred to a microwave extraction device and microwaved at a power of 560W for 60 minutes. The distillate was continuously condensed using a cooling system outside the microwave cavity, and the condensate was refluxed back into the extraction container to obtain arborvitae essential oil. The obtained arborvitae essential oil was stored at 4℃ in the dark.
[0054] S2: 100g of styrene and 2g of azobisisobutyronitrile are heated to 58℃ and mixed and dissolved in a beaker to obtain a prepolymer solution. The prepolymer solution is poured into a polytetrafluoroethylene box and stirred and reacted at 23℃ for 32 minutes to obtain non-crosslinked polystyrene.
[0055] S3: Dissolve 1.0g of non-crosslinked polystyrene in 11g of dichloromethane, and then mix it with 3.0g of arborvitae essential oil to form an oil phase; disperse the resulting oil phase in an aqueous solution containing 1.0wt% polyvinyl alcohol, stir at 23°C for 12min, then raise the temperature to 42°C and hold for 1.2h, and then raise the temperature to 75°C and hold for 32min to evaporate the solvent from the oil droplets, and construct an intermediate non-crosslinked polystyrene shell as a core material on the oil droplets of arborvitae essential oil;
[0056] S4: A composite solution of gum arabic and gelatin in a mass ratio of 1:1.2 (the mass ratio of solute to solvent in the composite solution is 1.25%, the solvent is water, and the solutes are gum arabic and gelatin) was added as the wall material. The mass ratio of the core material to the wall material was 1:1. After emulsification using a high-speed dispersion homogenizer, the mixture was poured into a three-necked flask and stirred at 38°C. The pH was adjusted to 4 with acetic acid, and the reaction was carried out for 28 minutes for a composite coagulation reaction. The mixture was stirred at 13°C, and the pH was adjusted to 5 with sodium hydroxide. Transglutaminase at a ratio of 25 u / g gelatin was added for a solidification reaction. After 2.3 hours of reaction, stirring was stopped, and the reaction was continued for 13 hours for solidification. After the solidification reaction, the product was filtered, washed, and precipitated to obtain wet capsules of microcapsules. The wet capsules of microcapsules were refrigerated overnight and then freeze-dried to obtain powdered arborvitae essential oil microcapsules.
[0057] Example 7 of the present invention is: a method for preparing arborvitae essential oil microcapsules, comprising the following steps:
[0058] S1: Fresh arborvitae seed pericarp waste was placed in a flask, and cellulase at a mass ratio of 1% was added. The mixture was then cultured in a water bath at a constant temperature of 50℃ for 2 hours. The mixture was then transferred to a microwave extraction device and microwaved at a power of 560W for 60 minutes. The distillate was continuously condensed using a cooling system outside the microwave cavity, and the condensate was refluxed back into the extraction container to obtain arborvitae essential oil. The obtained arborvitae essential oil was stored at 4℃ in the dark.
[0059] S2: 100g of styrene and 2g of azobisisobutyronitrile are heated to 62℃ and mixed and dissolved in a beaker to obtain a prepolymer solution. The prepolymer solution is poured into a polytetrafluoroethylene box and stirred and reacted at 27℃ for 28 minutes to obtain non-crosslinked polystyrene.
[0060] S3: Dissolve 3.0g of non-crosslinked polystyrene in 8.0g of dichloromethane, and then mix it with 3.0g of arborvitae essential oil to form an oil phase; disperse the resulting oil phase in an aqueous solution containing 1.0wt% polyvinyl alcohol, stir at 27°C for 8min, then raise the temperature to 48°C and hold for 0.8h, then raise the temperature to 85°C and hold for 28min to evaporate the solvent from the oil droplets, and construct an intermediate non-crosslinked polystyrene shell as a core material on the oil droplets of arborvitae essential oil;
[0061] S4: A composite solution of peach gum and gelatin in a mass ratio of 1:0.8 (the mass ratio of solute to solvent in the composite solution is 1.25%, the solvent is water, and the solutes are peach gum and gelatin) was added as the wall material. The mass ratio of the core material to the wall material was 1:1. After emulsification using a high-speed dispersion homogenizer, the mixture was poured into a three-necked flask and stirred at 42°C. The pH was adjusted to 4.5 with acetic acid, and the reaction was allowed to proceed for 32 minutes for a composite coagulation reaction. The mixture was then stirred at 17°C, and the pH was adjusted to 8 with sodium hydroxide. Transglutaminase at a ratio of 25 u / g gelatin was added for a solidification reaction. After 2.7 hours of reaction, stirring was stopped, and the reaction was allowed to continue for 10 hours for solidification. After the solidification reaction, the product was filtered, washed, and precipitated to obtain wet capsules of microcapsules. The wet capsules of microcapsules were refrigerated overnight and then freeze-dried to obtain powdered arborvitae essential oil microcapsules.
[0062] Example 8 of the present invention is: powdered arborvitae essential oil microcapsules prepared by Example 1.
[0063] Example 9 of the present invention is as follows: After immersing the fabric in a finishing agent containing the powdered arborvitae essential oil microcapsules of Example 8 at a certain temperature, the fabric is taken out, spun dry, and then baked and dried to obtain the aromatic textile finished with arborvitae oil microcapsules.
[0064] The comparative example of this invention is a method for preparing arborvitae essential oil microcapsules without non-crosslinked polystyrene, comprising the following steps:
[0065] S1: Fresh arborvitae seed pericarp waste was placed in a flask, and cellulase at a mass ratio of 1% was added. The mixture was then cultured in a water bath at a constant temperature of 50℃ for 2 hours. The mixture was then transferred to a microwave extraction device and microwaved at a power of 560W for 60 minutes. The distillate was continuously condensed using a cooling system outside the microwave cavity, and the condensate was refluxed back into the extraction container to obtain arborvitae essential oil. The obtained arborvitae essential oil was stored at 4℃ in the dark.
[0066] S2: 3.0g of arborvitae essential oil was dispersed in the aqueous phase to form oil droplets. A composite solution of gum arabic and gelatin in a mass ratio of 1:1 was added (the mass ratio of solute to solvent in the composite solution was 1.25%, with water as the solvent and gum arabic and gelatin as the solutes). After emulsification using a high-speed homogenizer, the mixture was poured into a three-necked flask and stirred at 40°C. The pH was adjusted to 4.3 with acetic acid, and the reaction was allowed to proceed for 10 minutes for a composite coagulation reaction. The mixture was stirred at 15°C, and the pH was adjusted to 6 with sodium hydroxide. Transglutaminase was added to initiate a solidification reaction. After 2.5 hours of reaction, stirring was stopped, and the reaction was continued for 12 hours for solidification. The solidified product was filtered, washed, and precipitated to obtain wet capsules of microcapsules. The wet capsules of microcapsules were refrigerated overnight and then freeze-dried to obtain powdered arborvitae essential oil microcapsules.
[0067] Sustained-release tests were conducted on the powdered arborvitae essential oil microcapsules of Examples 1-5 and the comparative examples during dialysis. The test results are shown in […]. Figure 1 The testing method is as follows:
[0068] The release of Platycladus orientalis essential oil from microcapsules was characterized using ultraviolet-visible (UV-vis) spectroscopy at λ = 245 nm. Platycladus orientalis essential oil microcapsules were placed in dialysis bags and then immersed in beakers containing 200 mL of sustained-release medium (anhydrous ethanol). 5 mL of dissolution medium was taken at different time intervals, and 5 mL of sustained-release medium was added immediately after each sample. The mass concentration of Platycladus orientalis essential oil was determined according to the Beer-Lambert law. All measurements were performed in triplicate. The sustained-release rate was analyzed using the following formula:
[0069]
[0070] Where: Q is the cumulative release rate of arborvitae essential oil from the microcapsules, in %; m is the total mass of arborvitae essential oil in the microcapsules, in g; V0 is the volume of the sustained-release medium, in mL; ρ i The value represents the mass concentration of arborvitae essential oil in the release medium, in g / mL; V is the volume of the sampling medium, in mL; and n is the number of samples.
[0071] Depend on Figure 1It can be seen that the comparative example, the arborvitae essential oil microcapsules without a viscous core structure, achieved a 100% essential oil release rate after 70 hours of dialysis. With increasing amounts of non-crosslinked polystyrene, the arborvitae essential oil microcapsules in Examples 1-5 achieved 100% essential oil release rates after 80, 90, 125, 150, and 150 hours, respectively. Compared to the comparative example, Examples 1-5, especially Examples 4 and 5, significantly prolonged the release time of the arborvitae essential oil. In Examples 1-3, due to a core-shell ratio ≥3:2, oil leakage occurred, resulting in shorter dialysis times compared to Examples 4 and 5. Examples 4 and 5 both achieved 100% essential oil release rates after 150 hours, indicating that further increasing the amount of non-crosslinked polystyrene when the core-shell ratio is 3:2 has no significant effect on prolonging the essential oil release time; therefore, the optimal core-shell ratio is 3:2. These test results demonstrate that the microcapsules of this invention exhibit excellent slow-release control during storage, reducing and controlling the essential oil release rate, and possessing excellent stability.
[0072] In summary, the method for preparing Platycladus orientalis essential oil microcapsules provided by this invention uses Platycladus orientalis essential oil obtained by supercritical CO2 extraction as the core material to obtain essential oil with superior color, aroma, and purity. Dichloromethane is volatilized through heating and stirring, constructing an intermediate non-crosslinked polystyrene shell on the oil droplets of Platycladus orientalis essential oil. Then, a gum arabic-gelatin outer wall material is prepared. Over time, the Platycladus orientalis essential oil dissolves the intermediate non-crosslinked polymer shell into a viscous core, increasing the viscosity of the essential oil. This results in the preparation of Platycladus orientalis essential oil microcapsules with extremely long-lasting release properties, ensuring that even after the microcapsules rupture, the essential oil still exhibits slow release characteristics for sustained efficacy. The gum arabic-gelatin solution is used as the wall material, and transglutaminase is selected to solidify the microcapsules. Transglutaminase catalyzes intramolecular and intermolecular covalent crosslinking of proteins and peptides without improving the stability of the wall material. Gum arabic has effects such as enhancing immunity, anti-tumor activity, scavenging free radicals, anti-aging, anti-infection, lowering blood lipids, and lowering blood sugar, which can endow the microcapsules with certain medicinal properties.
[0073] In preparing the oil phase, non-crosslinked polystyrene was first dissolved in dichloromethane to reduce the difficulty of mixing with arborvitae essential oil. The oil phase was then dispersed in an aqueous solution containing polyvinyl alcohol (PVA). PVA acts as a protective colloid, forming a protective film, reducing interfacial tension (improving the dispersion stability of the system), and increasing the system viscosity during the reaction. When the pH of the solution is below 4.7, the gelatin exhibits a positive charge and readily combines with negatively charged ions in the solution to form a gel. Therefore, the pH was adjusted to 4–4.5 during the coagulation process. Finally, after purification and drying, powdered arborvitae essential oil microcapsules were obtained, which are more conducive to preservation and use.
[0074] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.
Claims
1. A method for preparing arborvitae essential oil microcapsules, characterized in that, Includes the following steps: S1: Dissolve non-crosslinked polystyrene in dichloromethane, then mix it with arborvitae essential oil to form an oil phase; disperse the resulting oil phase in a polyvinyl alcohol aqueous solution to react and construct an intermediate non-crosslinked polystyrene shell on the oil droplets of arborvitae essential oil; S2: Add a composite solution containing gum arabic and gelatin to the product of S1 for emulsification, and then carry out a composite coagulation reaction and a solidification reaction in sequence to obtain arborvitae essential oil microcapsules; arborvitae essential oil can dissolve the intermediate non-crosslinked polymer shell into a viscous core over time.
2. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The preparation method of the non-crosslinked polystyrene is as follows: styrene and azobisisobutyronitrile are heated to 58~62℃ and mixed and dissolved to obtain a prepolymer solution. The prepolymer solution is stirred and reacted at 23~27℃ for 28~32 minutes to obtain non-crosslinked polystyrene.
3. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The reaction conditions for S1 are as follows: stirring at 23~27℃ for 8~12 min, then heating to 42~48℃ and holding for 0.8~1.2 h, followed by heating to 75~85℃ and holding for 28~32 min.
4. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The mass ratio of non-crosslinked polystyrene to dichloromethane in S1 is 1:11 to 3:
8.
5. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The mass ratio of peach gum to gelatin is 1:0.8 to 1:1.
2.
6. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The reaction conditions for the composite coagulation reaction are as follows: stirring at a temperature of 38~42℃, adjusting the pH to 4~4.5, and reacting for 28~32 minutes.
7. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The curing reaction conditions are as follows: stirring is carried out at a temperature of 13~17℃, the pH is adjusted to 5~8, transglutaminase is added to carry out the curing reaction, stirring is stopped after 2.3~2.7h, and the reaction continues for 10~13h.
8. The method for preparing arborvitae essential oil microcapsules according to claim 1, characterized in that, The product obtained after the curing reaction is filtered, washed and precipitated to obtain wet capsules of microcapsules. The wet capsules of microcapsules are refrigerated overnight and then freeze-dried to obtain powdered arborvitae essential oil microcapsules.
9. The arborvitae essential oil microcapsules prepared by the method for preparing arborvitae essential oil microcapsules according to any one of claims 1-8.
10. The application of the arborvitae essential oil microcapsules as described in claim 9 in textiles.