Disclosure of Invention
In order to solve the problems and achieve the corresponding purpose, the invention provides rosemary essential oil nanoliposome and a preparation method and application thereof. The rosemary essential oil nano liposome prepared by the invention overcomes the defects in the using process, has better slow release effect and better exerts the pharmacological activity. And under the action of better permeation promotion and better biological viscosity of the liposome, the retention amount and retention time of the medicament on the skin are increased, and the local effect of the medicament is better exerted.
The invention is realized by the following technical scheme
The invention provides a preparation method of rosemary essential oil nano liposome, which comprises the following steps:
(1) dissolving rosemary essential oil in caprylic capric triglyceride, and uniformly mixing to obtain a first mixture;
(2) dissolving the molten poloxamer in deionized water, standing, and fully stirring to obtain a second mixture;
(3) slowly adding the second mixture into the first mixture, stirring uniformly to obtain a third mixture, treating the third mixture in a high-pressure homogenizer, and cooling to below 24 ℃ after treatment to obtain the rosemary essential oil nanoliposome.
The preparation method of the rosemary essential oil nanoliposome comprises the following steps of (1) extracting rosemary from rosemary essential oil by a steam distillation method, and specifically comprises the following steps: taking fresh rosemary leaves, drying in shade, then placing in water for steam distillation to extract essential oil in the rosemary leaves, wherein the mass ratio of the dried rosemary leaves to the water in the extraction is 1: 10-14, distilling and extracting for 3-3.5 hours.
According to the preparation method of the rosemary essential oil nanoliposome, in the step (1), the mass ratio of rosemary essential oil to caprylic capric triglyceride is 1: 35 to 50.
According to the preparation method of the rosemary essential oil nanoliposome, in the step (2), the dosage ratio of the molten poloxamer to the deionized water in the second mixture is 3 g: (16-40) ml.
According to the preparation method of the rosemary essential oil nanoliposome, the temperature of the molten poloxamer is 70 ℃, and the molten poloxamer is dissolved in deionized water and then stands for 24 hours.
According to the preparation method of the rosemary essential oil nano-liposome, the mass ratio of rosemary essential oil to molten poloxamer is 1: 7 to 8.
According to the preparation method of the rosemary essential oil nanoliposome, after the second mixture in the step (3) is completely added into the first mixture, the stirring speed is 18000-21000 rpm, and the stirring time is 10-18 min.
And (3) when the third mixture is treated in a high-pressure homogenizer, the working pressure of the high-pressure homogenizer is 80MPa, and the homogenization treatment is carried out for 8-10 times.
According to the invention, through the interaction, the rosemary essential oil is coated, the coating rate reaches 81.9%, and the coating effect is good. The rosemary extract can be better used for in-vitro preparations, plays the role of rosemary essential oil and has good stability. The preparation method is simple, the use amount of the reagents is small, the reagents interact with each other by better controlling the small amount of the reagents, the outstanding coating effect on the rosemary essential oil is achieved, and the technical problem that the high coating rate cannot be achieved by adopting fewer kinds of reagents in the prior art is effectively solved.
The invention also provides the rosemary essential oil nanoliposome prepared by the preparation method of the rosemary essential oil nanoliposome.
The rosemary essential oil nanoliposome has a coating rate of 81.9% on rosemary essential oil, has good stability, overcomes the defects of difficult dissolution in water, easy volatilization and unstable peculiar smell of the rosemary essential oil, and enables the rosemary essential oil to be better applied.
The invention provides application of the rosemary essential oil nanoliposome in an external preparation. The rosemary essential oil nano liposome prepared by the invention can be used in cosmetics and in vitro pharmaceutical preparations.
Compared with the prior art, the invention has the following positive beneficial effects
Rosemary essential oil is widely researched due to the outstanding antioxidant performance, but is limited due to the defects of volatility, peculiar smell, instability and the like, and the prior art has the defect that the rosemary essential oil is prepared into the nano liposome to overcome the defects of volatility, instability and the like. However, when the reagent is used for coating rosemary essential oil improperly, the rosemary essential oil is difficult to coat well, multiple reagents are consumed, toxic reagents are used, and the consumption of the reagents is increased, so that great influence is brought to the environment and technicians.
According to the rosemary essential oil coating method, the caprylic/capric triglyceride and the poloxamer are subjected to emulsification interaction, so that the rosemary essential oil can be coated well, the coating rate reaches 81.9%, no additional reagent is needed in the coating preparation process, no toxic reagent is used, the whole preparation process is environment-friendly, green and harmless, and the method is simple and easy to carry out; the caprylic capric triglyceride has better viscosity and thixotropy, and the rosemary essential oil nanoliposome prepared by the invention has better viscosity and thixotropy, so that the high application of an in-vitro preparation is facilitated, namely the defect that the nanoliposome is lack of viscosity and thixotropy is overcome under the condition that no additional reagent is added.
The rosemary essential oil nanoliposome prepared by the invention can overcome the defects that rosemary essential oil is difficult to dissolve, volatile, peculiar smell and unstable in water, has good slow release effect and can better exert the pharmacological activity, and under the condition of coating the liposome, the retention amount and retention time of a medicament on the skin are increased, and the local effect of the medicament is better exerted.
The method is simple and easy to implement, few in used reagents and low in preparation cost, and the obtained rosemary essential oil nanoliposome is high in coating rate and has a good application prospect.
Detailed Description
The present invention will be described in more detail with reference to the following embodiments for understanding the technical solutions of the present invention, but the present invention is not limited to the scope of the present invention.
Example 1
A preparation method of rosemary essential oil nano-liposome comprises the following steps:
(1) drying fresh rosemary leaves in the shade, then placing the dried rosemary leaves in water for steam distillation to extract essential oil in the rosemary leaves, wherein the mass ratio of the rosemary leaves dried in the shade to the water in the extraction is 1: 10, distilling and extracting for 3 hours;
(2) dissolving rosemary essential oil in caprylic capric triglyceride, and mixing uniformly to obtain a first mixture; wherein the mass ratio of the rosemary essential oil to the caprylic capric triglyceride is 1: 35;
(3) dissolving 70 ℃ molten poloxamer in deionized water, uniformly mixing, standing for 24 hours, and fully stirring after standing to obtain a second mixture; wherein the dosage ratio of the molten poloxamer to the deionized water is 3 g: 16ml of the solution;
(4) continuously and slowly adding the second mixture into the first mixture (mixing rosemary essential oil and molten poloxamer at a mass ratio of 1: 7), stirring at 18000rpm for 18min after the second mixture is completely added, and uniformly stirring to obtain a third mixture;
(5) and (3) placing the third mixture into a high-pressure homogenizer for processing, wherein the working pressure of the high-pressure homogenizer is 80MPa, homogenizing for 8 times, and then cooling to below 24 ℃ to obtain the rosemary essential oil nanoliposome.
Example 2
A preparation method of rosemary essential oil nano-liposome comprises the following steps:
(1) drying fresh rosemary leaves in the shade, then placing the dried rosemary leaves in water for steam distillation to extract essential oil in the rosemary leaves, wherein the mass ratio of the rosemary leaves dried in the shade to the water in the extraction is 1: 14, distilling and extracting for 3.5 hours;
(2) dissolving rosemary essential oil in caprylic capric triglyceride, and mixing uniformly to obtain a first mixture; wherein the mass ratio of the rosemary essential oil to the caprylic capric triglyceride is 1: 50;
(3) dissolving 70 ℃ molten poloxamer in deionized water, uniformly mixing, standing for 24 hours, and fully stirring after standing to obtain a second mixture; wherein the dosage ratio of the molten poloxamer to the deionized water is 3 g: 40 ml;
(4) continuously and slowly adding the second mixture into the first mixture (mixing the rosemary essential oil and the molten poloxamer according to the mass ratio of 1: 8), completely adding the second mixture, stirring at the stirring speed of 21000rpm for 10min, and uniformly stirring to obtain a third mixture;
(5) and (3) placing the third mixture into a high-pressure homogenizer for processing, wherein the working pressure of the high-pressure homogenizer is 80MPa, homogenizing for 10 times, and then cooling to below 24 ℃ to obtain the rosemary essential oil nanoliposome.
Example 3
A preparation method of rosemary essential oil nano-liposome comprises the following steps:
(1) drying fresh rosemary leaves in the shade, then placing the dried rosemary leaves in water for steam distillation to extract essential oil in the rosemary leaves, wherein the mass ratio of the rosemary leaves dried in the shade to the water in the extraction is 1: 12, distilling and extracting for 3 hours;
(2) dissolving rosemary essential oil in caprylic capric triglyceride, and mixing uniformly to obtain a first mixture; wherein the mass ratio of the rosemary essential oil to the caprylic capric triglyceride is 1: 42;
(3) dissolving 70 ℃ molten poloxamer in deionized water, uniformly mixing, standing for 24 hours, and fully stirring after standing to obtain a second mixture; wherein the dosage ratio of the molten poloxamer to the deionized water is 3 g: 28 ml;
(4) continuously and slowly adding the second mixture into the first mixture (mixing rosemary essential oil and molten poloxamer at a mass ratio of 1: 7.5), stirring at 20000rpm for 15min after the second mixture is completely added, and stirring uniformly to obtain a third mixture;
(5) and (3) placing the third mixture into a high-pressure homogenizer for processing, wherein the working pressure of the high-pressure homogenizer is 80MPa, homogenizing for 9 times, and then cooling to below 24 ℃ to obtain the rosemary essential oil nanoliposome.
Example 4
A preparation method of rosemary essential oil nano-liposome comprises the following steps:
(1) drying fresh rosemary leaves in the shade, then placing the dried rosemary leaves in water for steam distillation to extract essential oil in the rosemary leaves, wherein the mass ratio of the rosemary leaves dried in the shade to the water in the extraction is 1: 12, distilling and extracting for 3 hours;
(2) dissolving rosemary essential oil in caprylic capric triglyceride, and mixing uniformly to obtain a first mixture; wherein the mass ratio of the rosemary essential oil to the caprylic capric triglyceride is 1: 40;
(3) dissolving 70 ℃ molten poloxamer in deionized water, uniformly mixing, standing for 24 hours, and fully stirring after standing to obtain a second mixture; wherein the dosage ratio of the molten poloxamer to the deionized water is 3 g: 20ml of the solution;
(4) continuously and slowly adding the second mixture into the first mixture (mixing rosemary essential oil and molten poloxamer at a mass ratio of 1: 7.5), stirring at 20000rpm for 15min after the second mixture is completely added, and stirring uniformly to obtain a third mixture;
(5) and (3) placing the third mixture into a high-pressure homogenizer for processing, wherein the working pressure of the high-pressure homogenizer is 80MPa, homogenizing for 9 times, and then cooling to below 24 ℃ to obtain the rosemary essential oil nanoliposome.
Example 5
The preparation method of example 4 is adopted to prepare the rosemary essential oil nanoliposome, and the performance of the rosemary essential oil nanoliposome is detected, specifically as follows.
1. Preparing rosemary essential oil nano liposome:
(1) drying fresh rosemary leaves in the shade, then placing the dried rosemary leaves in water for steam distillation to extract essential oil in the rosemary leaves, wherein the mass ratio of the rosemary leaves dried in the shade to the water in the extraction is 1: 12, distilling and extracting for 3 hours;
(2) dissolving 200mg of rosemary essential oil prepared in the step (1) in 8g of caprylic/capric triglyceride, and uniformly mixing to obtain a first mixture;
(3) dissolving 1.5g of poloxamer molten at 70 ℃ in 10ml of deionized water, uniformly mixing, standing for 24 hours, and fully stirring after standing to obtain a second mixture;
(4) continuously and slowly adding the second mixture into the first mixture, stirring for 15min at the stirring speed of 20000rpm after the second mixture is completely added, and uniformly stirring to obtain a third mixture;
(5) and (3) placing the third mixture into a high-pressure homogenizer for processing, wherein the working pressure of the high-pressure homogenizer is 80MPa, homogenizing for 9 times, and then cooling to below 24 ℃ to obtain the rosemary essential oil nanoliposome.
2. The rosemary essential oil nanoliposomes prepared above were evaluated for appearance, particle size and zeta potential using laser diffraction techniques (Malvern Instruments, UK).
(1): morphology characteristics of rosemary essential oil nanoliposome (REO-NLC) were evaluated by using a Scanning Electron Microscope (SEM) (KYKY-EM3200) (results are shown in figure 1), particle size was measured by a Malvenano ZS90 particle size analyzer (results are shown in figure 3), and zeta potential (results are shown in figure 2).
(2): the entrapment rate (EE%) and the drug-loading rate (DL%) of the nano-liposome are detected by taking rosmarinic acid as an index:
EE(%)=(1-Cf/Ct)×100%
DL(%)=We/Wm×100%
wherein EE represents encapsulation efficiency, CfIn terms of the amount of free rosmarinic acid, CtIs the total amount of rosmarinic acid in nanoparticle or liposome suspension. Wherein DL represents the percentage of the drug-loading of rosemary oil in the liposome, WeDenotes the amount of rosemary essential oil encapsulated in liposomes, WmRepresents the total weight of the (drug-loaded) liposomes.
The detection values are shown in the following table 1, and the encapsulation rate of REO-NLC in the prepared nano-liposome is 81.9 percent and is up to more than 82 percent according to the calculation of the data in the table 1, and the drug loading rate is 12.3 percent.
TABLE 1 content, encapsulation efficiency and drug loading of rosmarinic acid in REO-NLC
(3): the antibacterial activity of the rosemary essential oil nanoliposome is measured by a disc diffusion method:
get 1060.10ml of bacteria per ml is inoculated in a culture medium for culture; then 100mg REO and 100mg REO-NLCs were placed on the inoculation plate and inoculated at 37 ℃ for 7 days.
The positive control was mupirocin, while the negative control was a sterile dish containing 10% DMSO and NLC (blank).
The length of the zone of inhibition was compared in mm for the drug and control groups.
6 disks per group, the results are shown in FIG. 4; there is no significant difference between REO and REO-NLCs, and REO-NLCs are more stable.
(4): determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC)
A96-well microplate was loaded with 100. mu.l of bacteria per well. Then 100. mu.l REO and 100. mu.l REO-NLC were added to and mixed with the substances in the wells, respectively, and then 100ml wells containing the sample were transferred to the wells of the second column, and the transfer was repeated. All wells in each column receive half of the nanoparticles in the previous column. The bacterial test inoculum size is 106CFU/ml。
The plates were then incubated at 37 ℃ for 24 hours. The growth of the microorganisms is monitored by measuring the absorbance. 620nm in a Power Wave microplate spectrophotometer (BioTek Germany). The lowest concentration and lowest turbidity well was determined as the MIC value. All measurements were repeated three times.
For the MBC test, 50ml were removed from the wells for MIC analysis, plated on nutrient agar plates, and incubated at 37 ℃ for 24 hours. After the incubation time, the plates were examined for growth. The lowest concentrations of REO and REO-NLC were considered as MBC values and the results are shown in table 2.
TABLE 2 MIC and MBC data in REO and REO-NLC groups
As shown in table 2, REO-NLC and REO have the greatest antibacterial activity against positive bacteria including staphylococcus epidermidis, staphylococcus aureus and listeria monocytogenes. The mean values for MIC and MBC were between 4.9 and 20mg/ml (Table 2).
Therefore, the invention researches and prepares the rosemary nanoliposome (REO-NLC) with high entrapment rate and high physical stability, and researches the in vitro antibacterial performance. The results prove that the rosemary nano liposome has high encapsulation efficiency, stable drug-loading rate and better biocompatibility; in vitro bacteriostatic experiments also confirmed that: REO-NLC and REO have the greatest antibacterial activity against positive bacteria including Staphylococcus epidermidis, Staphylococcus aureus and Listeria monocytogenes, without significant difference.