Water-soluble origanum vulgare essential oil antibacterial agent

Abstract

The invention relates to a water-soluble origanum vulgare essential oil antibacterial agent and a preparation method thereof. The preparation method comprises the step of catalyzing a ring-opening polymerization reaction of hydroxyl in the origanum vulgare essential oil and ethylene oxide by adopting boron trifluoride diethyl etherate. The preparation method is simple in synthetic route, low in reaction temperature and short in reaction time. The prepared antibacterial agent has good water solubility, and keeps the good antibacterial performance of the oregano essential oil. The antibacterial agent can be widely used for bacteriostasis and corrosion prevention of hygienic products, daily chemical products, cosmetics and other products containing more water. The effective additive amount of the antibacterial agent is 0.10-0.12% of the total mass of the product.

Description

Technical Field

[0001] The invention relates to a preparation method and application of a water-soluble oregano essential oil antibacterial agent. Background Art

[0002] Oregano is a perennial herbaceous plant of the genus Origanum in the family Lamiaceae. Oregano oil is a light yellow, natural essential oil extracted from the stems and leaves through steam distillation. It has a refreshing, herbal aroma. Oregano essential oil has a wide range of medicinal uses and a long history of use. It is widely used in traditional medicine and health maintenance, particularly for its potent antiseptic properties.

[0003] Oregano essential oil is insoluble in water, making its excellent antibacterial properties unsuitable for use in water-based products (such as wipes, facial masks, oil-in-water creams, and body washes) because fungi primarily reside in the aqueous phase. While conventional surfactant solubilization techniques can dissolve oregano essential oil in water, this solubilization process involves encapsulating the oregano essential oil in the form of micelles, preventing the oil from actually entering the aqueous phase. This severely limits its widespread application. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a preparation method of an ethylene oxide chemically modified oregano essential oil antibacterial agent and the prepared water-soluble oregano essential oil antibacterial agent.

[0005] According to public data, the composition of oregano essential oil is complex and diverse. Its main chemical components are carvacrol and thymol, of which the content of carvacrol is about 60% and the content of thymol is about 8%. In addition to phenolic compounds, oregano essential oil also contains a certain proportion of alcohol compounds, such as linalool, linalool, and menthol. The structural characteristics of the above phenolic compounds and alcohol compounds are that they all contain one or more hydroxyl groups, so they have high chemical modifiability. The hydroxyl groups and ethylene oxide in the compounds undergo ring-opening polymerization in the presence of a catalyst to form ethylene glycol chains. Ethylene glycol chains easily form hydrogen bonds in water, and therefore have good water solubility.

[0006] The present invention uses oregano essential oil and ethylene oxide as main raw materials. A ring-opening polymerization reaction occurs between the hydroxyl groups in the oregano essential oil molecules and ethylene oxide in the presence of a catalyst, boron trifluoride etherate, to synthesize an ethylene oxide-modified water-soluble oregano essential oil antibacterial agent. The oregano essential oil antibacterial agent is a mixture of oregano essential oil polyoxyethylene ethers, all of which are produced by the same reaction.

[0007] The preparation method of the water-soluble oregano essential oil antibacterial agent of the present invention: At room temperature, add oregano essential oil and boron trifluoride etherate in a 50:1 mass ratio to a reactor. Seal the reactor and heat to 60°C while stirring at 100 rpm. Evacuate the reactor and purge with nitrogen five times to maintain an inert atmosphere. Add ethylene oxide in an amount equal to three times the mass of the oregano essential oil. After the addition of ethylene oxide, maintain the original temperature and stirring rate until the reactor pressure drops to near zero and remains essentially constant. Cool the reactor with condensed water until the temperature drops to room temperature before discharging the product.

[0008] The final product is the water-soluble oregano essential oil antibacterial agent of the present invention, which is a light yellow transparent viscous liquid with a viscosity of 35 Pa·s (25°C) and a pH value of 6.8. Its maximum solubility in water at 25°C is 8 g / 100 ml.

[0009] The antibacterial experiment of the water-soluble oregano essential oil antibacterial agent of the present invention is as follows: A water-soluble oregano essential oil antimicrobial agent was prepared using sterile distilled water at a series of concentration gradients (mass percentage: 0.04%, 0.06%, 0.08%, 0.10%, and 0.12%). Its 20-minute antibacterial properties against Staphylococcus aureus (a representative species of pyogenic cocci), Escherichia coli (a representative species of enteric infection), and Candida albicans (a representative species of fungi) were tested. The test results are shown in the table.

[0010] Antibacterial performance test results of water-soluble oregano essential oil antibacterial agent solutions with different concentrations The data in the table show that when the mass percentage of the antimicrobial agent was 0.10%, the inhibition rate against all three representative bacterial species was >90%, demonstrating a strong antibacterial effect. At a mass percentage of 0.12%, the inhibition rate reached 100% against all three representative bacterial species. At the same dose, the antimicrobial agent exhibited varying antibacterial effects against the three bacterial species, with the strongest effect against Staphylococcus aureus, followed by Escherichia coli, and a relatively weaker effect against Candida albicans.

[0011] The antibacterial mechanism of the antibacterial agent involved in the present invention is mainly to inhibit the reaction of certain enzymes in fungi or microorganisms or to inhibit the synthesis of enzymes in biological cells.

[0012] The preparation method of the water-soluble oregano essential oil antibacterial agent of the present invention has a simple synthesis route, low reaction temperature, short reaction time and low energy consumption during industrial production.

[0013] The water-soluble oregano essential oil antibacterial agent disclosed herein has the advantages of having good water solubility through simple chemical modification while maintaining the good antibacterial properties of the oregano essential oil itself, overcoming the disadvantage that the oregano essential oil cannot be used for aqueous antibacterial purposes. Therefore, the agent has broad application prospects and is particularly suitable for use in sanitary products, daily chemical products, cosmetics, and other fields containing a large amount of water, such as wet wipes, facial masks, shower gels, and lotions.

[0014] The amount of the antibacterial agent added is 0.10-0.12% of the total mass of the product, i.e., the mass percentage concentration is 0.10-0.12%. Tests have shown that the water-soluble oregano essential oil antibacterial agent of the present invention is non-irritating to the skin and vaginal mucosa at an effective addition dose, and does not cause skin allergic reactions. DETAILED DESCRIPTION

[0015] The present invention is further described through examples, the purpose of which is only to provide a better understanding of the content of the present invention. Therefore, the examples given do not limit the scope of protection of the present invention.

[0016] Example: Preparation of water-soluble oregano essential oil antibacterial agent 1. Check the vacuum degree of the reactor to ensure that there is no leakage in the pipeline and the nitrogen is flowing smoothly.

[0017] 2. At room temperature, add 500 g of commercially available oregano essential oil and 10 g of boron trifluoride etherate as a catalyst into a reaction kettle, seal it, heat it to 60°C, and stir it (100 r / min).

[0018] 3. Evacuate the reactor and pass nitrogen gas, repeat 5 times to keep the reactor in an inert gas environment.

[0019] 4. Add 1500 g of ethylene oxide and continue the reaction at the original temperature and stirring speed. The reaction is completed when the pressure in the reactor drops to a value close to zero and remains substantially unchanged.

[0020] 5. Connect condensed water for cooling, wait until the temperature drops to room temperature, and then discharge the material. The obtained light yellow transparent viscous liquid is the water-soluble oregano essential oil antibacterial agent.

Claims

1. A method for preparing a water-soluble oregano essential oil antibacterial agent, comprising: At room temperature, add oregano essential oil and boron trifluoride etherate in a 50:1 mass ratio to a reactor. Seal the reactor and heat to 60°C while stirring at 100 rpm. Evacuate the reactor and purge with nitrogen five times to maintain an inert atmosphere. Add ethylene oxide in an amount equal to three times the mass of the oregano essential oil. After the addition of ethylene oxide, maintain the original temperature and stirring rate until the reactor pressure drops to near zero and remains essentially constant. Cool the reactor with condensed water until the temperature drops to room temperature before discharging the product.

2. the preparation method of water-soluble oregano essential oil antibacterial agent according to claim 1, its prepared water-soluble oregano essential oil antibacterial agent is used in sanitary products, daily chemical products and cosmetics fields.

3. According to claims 1 to 2, the addition amount of the water-soluble oregano essential oil antibacterial agent is 0.10 to 0.12% of the total mass of the product, that is, the mass percentage concentration of the water-soluble oregano essential oil antibacterial agent is 0.10 to 0.12%.

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