Preparation method and equipment of edible clausena lansium leaf essential oil chitosan antibacterial film

Abstract

The invention belongs to the technical field of antibacterial films, and particularly relates to a preparation method and equipment of an edible clausena lansium leaf essential oil chitosan antibacterial film, and the preparation method comprises the following specific steps: adding 2g of chitosan into a 1% acetic acid solution, stirring at 50 DEG C for 2 hours by a magnetic stirrer until the chitosan is completely dissolved to form a uniform solution, and then adding the chitosan into the uniform solution to obtain the clausena lansium leaf essential oil chitosan antibacterial film. The preparation method comprises the following steps: adding 1.5 g of gelatin into 100 ml of a chitosan solution with the volume fraction of 2%, heating to 50 DEG C by using a water bath, and stirring for 30 minutes, so that the gelatin and the chitosan solution are fully mixed; the traditional Chinese medicine composition shows a good inhibition effect on common food-borne pathogenic bacteria and oral pathogenic bacteria, and effectively prevents microbial contamination and cross infection.

Description

Technical Field

[0001] The invention relates to the technical field of antibacterial films, in particular to a preparation method and equipment of an edible pampas grass leaf essential oil chitosan antibacterial film. Background Art

[0002] As the public's demand for food safety, healthy living, and environmentally friendly materials continues to increase, the development of packaging and care materials that are both highly effective in antibacterial and safe and non-toxic has become a hot topic in current research. However, the existing antibacterial films have the following problems in practical applications:

[0003] 1. Most traditional antibacterial films use chemical preservatives, metal nanoparticles or synthetic antibacterial agents, which can provide high antibacterial activity in the short term, but often have risks of toxicity, drug resistance and environmental pollution;

[0004] 2. Some antibacterial films are only effective against specific microorganisms (for example, nisin has a strong inhibitory effect on Gram-positive bacteria (such as Staphylococcus aureus, Streptococcus, Clostridium botulinum)), and have weak inhibitory effects on other microorganisms (for example, the inhibitory effect on Gram-negative bacteria (such as Escherichia coli), yeast and mold is significantly weakened);

[0005] 3. Some preparation processes are complex and costly, which is not conducive to large-scale promotion and application. At the same time, it is difficult to fully meet the safety requirements for packaging or care objects (such as food and oral care products).

[0006] Therefore, a method and equipment for preparing an edible yellow peel leaf essential oil chitosan antibacterial film is invented. Summary of the invention

[0007] In view of the above and / or existing problems in the method for preparing an edible pampas grass leaf essential oil chitosan antibacterial film and the equipment thereof, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to provide a method and equipment for preparing an edible yellow peel leaf essential oil chitosan antibacterial film, which can solve the above-mentioned existing problems.

[0009] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions:

[0010] A method for preparing an edible yellow calendula leaf essential oil chitosan antibacterial film comprises the following specific steps:

[0011] Step 1: Add 2 g of chitosan to 1% acetic acid solution and stir at 50°C for 2 hours using a magnetic stirrer until the chitosan is completely dissolved to form a uniform solution;

[0012] Step 2: Add 1.5 g of gelatin to 100 ml of 2% chitosan solution, heat to 50° C. in a water bath, and stir for 30 minutes to fully mix the gelatin and chitosan solution;

[0013] Step 3: Add 1.5 ml of glycerol, 0.4 ml of Phellodendron chinense essential oil, 0.5 ml of Tween-80 and 0.3 g of calcium chloride to the mixture, and stir at a speed of 10,000 rpm for 5 minutes using a homogenizer to prepare a uniform chitosan-Phellodendron chinense essential oil composite membrane liquid;

[0014] Step 4: Degas the prepared film-forming liquid for a period of 0.5 to 2 hours to remove bubbles and improve the quality of the film. The degassed film-forming liquid is then poured into a mold and dried for 5 hours until a film is formed.

[0015] A device for preparing an edible pomelo leaf essential oil chitosan antibacterial film comprises a base and a container, wherein a first block is fixedly installed on the bottom of the container, a magnetic stirrer with a drying function is arranged on the left side of the top of the base, a homogenizer with a water bath function is arranged on the right side of the top of the base, and a degassing component is arranged on the homogenizer.

[0016] As a preferred embodiment of the equipment for preparing an edible yellow calendula leaf essential oil chitosan antibacterial film according to the present invention, the magnetic stirrer comprises:

[0017] A magnetic stirrer body, wherein the magnetic stirrer body is fixedly mounted on the top left side of the base;

[0018] A first annular plate, wherein the first annular plate is fixedly mounted on the top outer side of the magnetic stirrer body;

[0019] An electric heating plate, the electric heating plate is fixedly mounted on the top inner side of the magnetic stirrer body, and the first block is inserted on the top of the electric heating plate;

[0020] The first hollow circular plate is fixedly mounted on the top end of the inner cavity of the first annular plate, and the inner cavity of the first hollow circular plate is provided with a container.

[0021] As a preferred embodiment of the equipment for preparing an edible yellow calendula leaf essential oil chitosan antibacterial film according to the present invention, the magnetic stirrer further comprises:

[0022] A first support plate, wherein the first annular plate is fixedly mounted on a side surface thereof via a first L-shaped rod;

[0023] A first cylinder, the first cylinder being fixedly mounted on the top of the first support plate;

[0024] A first sealing plate is fixedly mounted on the piston rod of the first cylinder, and the first sealing plate can be in contact with the container.

[0025] As a preferred embodiment of the equipment for preparing an edible yellow calendula leaf essential oil chitosan antibacterial film according to the present invention, the magnetic stirrer further comprises:

[0026] A first rotating rod, wherein the first rotating rod is fixedly mounted on the bottom of the first sealing plate;

[0027] A magnet, wherein the bottom end of the first rotating rod is rotatably connected to the magnet via a bearing;

[0028] A first temperature sensor is fixedly mounted on the bottom of the first sealing plate.

[0029] As a preferred solution of the equipment for preparing an edible yellow peel leaf essential oil chitosan antibacterial film according to the present invention, the homogenizer comprises:

[0030] A second annular plate for water is provided in its inner cavity, the second annular plate is fixedly mounted on the top right side of the base, and an electric heating pipe is fixedly mounted on the inner wall of the second annular plate;

[0031] A bearing plate, the bearing plate is fixedly mounted on the top right side of the base, and the bearing plate is located in the inner cavity of the second annular plate, and the first block is inserted on the top end of the bearing plate;

[0032] A second hollow circular plate, wherein the second hollow circular plate is fixedly mounted on the top end of the inner cavity of the second annular plate, and a container is provided in the inner cavity of the first hollow circular plate;

[0033] The heat exchange tube has its end fixedly mounted on the top of the second hollow circular plate, and a one-way valve is provided at one end of the heat exchange tube.

[0034] As a preferred embodiment of the equipment for preparing an edible yellow peel leaf essential oil chitosan antibacterial film according to the present invention, the homogenizer further comprises:

[0035] A second support plate, wherein the second annular plate is fixedly mounted on a side surface thereof via a second L-shaped rod;

[0036] a second cylinder, the second cylinder being fixedly mounted on the top of the second support plate;

[0037] A servo motor, wherein the piston rod of the second cylinder is fixedly mounted with the servo motor via a flange;

[0038] A second sealing plate, the output shaft of the servo motor is fixedly mounted with the second sealing plate, and the second sealing plate can be in contact with the container;

[0039] A second rotating rod, wherein the second rotating rod is fixedly mounted on the bottom of the second sealing plate;

[0040] A stirring tube, wherein the stirring tube is fixedly mounted on the side wall of the bottom end of the second rotating rod, and a second one-way valve is provided at one end of the stirring tube;

[0041] A second temperature sensor is fixedly mounted on the bottom of the second sealing plate.

[0042] As a preferred embodiment of the equipment for preparing an edible yellow peel leaf essential oil chitosan antibacterial film according to the present invention, the homogenizer further comprises:

[0043] An air pump, the air pump being fixedly mounted on the top right side of the second sealing plate;

[0044] An air outlet pipe, wherein the air outlet pipe is fixedly mounted on the air outlet end of the air pump, and one end of the air outlet pipe is fixedly mounted on the side wall of the second rotating rod;

[0045] A flow groove is provided in the second rotating rod, and the air outlet pipe is communicated with the flow groove.

[0046] As a preferred embodiment of the equipment for preparing an edible yellow peel leaf essential oil chitosan antibacterial film according to the present invention, the homogenizer further comprises:

[0047] A pipe with a valve disposed thereon, the pipe being fixedly mounted on the side wall of the first annular plate, and one end of the pipe being fixedly mounted on the side wall of the second annular plate;

[0048] A first one-way valve is provided at one end of the pipeline.

[0049] As a preferred solution of the equipment for preparing an edible yellow calendula leaf essential oil chitosan antibacterial film according to the present invention, the degassing component comprises:

[0050] A vacuum pump is fixedly installed on the top left side of the second support plate;

[0051] An air intake pipe is fixedly mounted on the air intake end of the vacuum pump, and one end of the air intake pipe is arranged in the second supporting plate.

[0052] Compared with the prior art, the present invention has the following technical effects:

[0053] 1. Broad-spectrum antibacterial effect: It has good inhibitory effects on a variety of foodborne pathogens and common oral pathogens such as Staphylococcus aureus, Candida albicans, Streptococcus mutans, Escherichia coli, etc., effectively preventing microbial contamination and cross infection;

[0054] 2. Sustained and long-lasting effect: The chitosan matrix is ​​used to slow-release the essential oil of the yellow tangerine peel, so that the antibacterial effect can be continuously released, ensuring that the product maintains antibacterial activity for a long time;

[0055] 3. Natural and edible, safe and environmentally friendly: All raw materials are of natural origin, meet the safety standards of food and medical materials, can be naturally degraded after use, do not cause environmental pollution, and meet the requirements of green and sustainable development;

[0056] 4. Simple process and large-scale production: The patent not only describes in detail the preparation method of the antibacterial film, but also designs the corresponding equipment scheme, which has good production stability and controllability, and is conducive to the realization of industrial promotion;

[0057] 5. Multifunctional application: In addition to its obvious advantages in food preservation and oral care, this technology can also be expanded to multiple fields such as medical dressings and fruit and vegetable preservation coatings, providing personalized solutions for different market needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a physical picture of the antibacterial film of the present invention;

[0059] Figure 2 Schematic diagram of in vitro drug release of the antibacterial film of the present invention;

[0060] Figure 3 Schematic diagram of the mechanical properties of the antibacterial film of the present invention;

[0061] Figure 4 This is a front view schematic diagram of the structure of the preparation equipment of the present invention;

[0062] Figure 5 For the present invention Figure 4 A schematic diagram of the structure enlargement in the middle;

[0063] Figure 6 It is a schematic diagram of the structure of the first annular plate and the first annular plate of the present invention;

[0064] Figure 7 It is a top view schematic diagram of the second annular plate, the second hollow circular plate and the heat exchange tube structure of the present invention;

[0065] Figure 8 This is a schematic diagram of the structure of the first support plate of the present invention;

[0066] Fig. 9 This is a schematic diagram of the first L-shaped rod structure of the present invention;

[0067] Fig.10 Schematic diagram of the antibacterial activity of different concentrations of the pomelo leaf essential oil of the present invention against different bacteria;

[0068] Fig.11It is a schematic diagram of the determination of the antibacterial performance of the chitosan antibacterial film release liquid of the pomelo leaf essential oil of the present invention.

[0069] In the figure: base 10, magnetic stirrer body 20, first annular plate 21, electric heating plate 22, first block 221, first hollow circular plate 23, first L-shaped rod 24, first support plate 25, first cylinder 26, first sealing plate 27, first rotating rod 28, magnet 29, first temperature sensor 291, second annular plate 30, bearing plate 31, second hollow circular plate 32, heat exchange tube 33, pipeline 34, first one-way valve 341, second L-shaped rod 35, second support plate 36, second cylinder 37, servo motor 38, second sealing plate 39, second rotating rod 391, stirring tube 392, second one-way valve 393, second temperature sensor 394, air pump 40, outlet pipe 41, circulation slot 42, vacuum pump 50, inlet pipe 51. DETAILED DESCRIPTION

[0070] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0071] The present invention provides a method for preparing an edible yellow peel leaf essential oil chitosan antibacterial film. Figure 1-Figure 11 , including the following specific steps:

[0072] Step 1: Add 2 g of chitosan to 1% acetic acid solution and stir at 50°C for 2 hours using a magnetic stirrer until the chitosan is completely dissolved to form a uniform solution;

[0073] Specifically, chitosan and acetic acid solution are placed in a container, and then the container is placed on the top of the electric heating plate 22. At this time, the first block 221 is inserted on the top of the electric heating plate 22. After that, the first sealing plate 27 is brought into contact with the container through the first cylinder 26. At this time, the magnetic block in the magnetic stirrer body 20 can be used to rotate the magnet 29 to achieve stirring of the chitosan and acetic acid solution. In this process, the temperature can be controlled at 50°C through the cooperation of the electric heating plate 22 and the first temperature sensor 291.

[0074] Step 2: Add 1.5 g of gelatin to 100 ml of 2% chitosan solution, heat to 50° C. in a water bath, and stir for 30 minutes to fully mix the gelatin and chitosan solution;

[0075] Specifically, the gelatin and chitosan solutions are placed in a container, and then the container is placed on the top of the carrier plate 31. At this time, the first block 221 is inserted on the top of the carrier plate 31. After that, the second sealing plate 39 is brought into contact with the container through the second cylinder 37. At this time, the stirring tube 392 is rotated by the servo motor 38 to achieve stirring of the gelatin and chitosan solutions. In this process, the water can be controlled at 50°C by the electric heating tube and the second temperature sensor. When the chitosan and acetic acid solutions are stirred, the heat discharged will flow into the water through the pipe 34 to preheat the water. In addition, the water vapor generated in the whole process will condense into water through the heat exchange tube 33 and return to the second annular plate 30.

[0076] Step 3: Add 1.5 ml of glycerol, 0.4 ml of Phellodendron chinense essential oil, 0.5 ml of Tween-80 and 0.3 g of calcium chloride to the mixture, and stir at a speed of 10,000 rpm for 5 minutes using a homogenizer to prepare a uniform chitosan-Phellodendron chinense essential oil composite membrane liquid;

[0077] Specifically, the mixture, glycerin, phellodendron leaf essential oil, Tween-80 and calcium chloride are placed in a container, and then the container is placed on the top of the carrier plate 31. At this time, the first block 221 is inserted on the top of the carrier plate 31. After that, the second sealing plate 39 is brought into contact with the container through the second cylinder 37. At this time, the stirring tube 392 is rotated by the servo motor 38 to achieve stirring of the mixture, glycerin, phellodendron leaf essential oil, Tween-80 and calcium chloride. In this process, air is allowed to flow into the container through the stirring tube 392 by the air pump 40, so that the mixture, glycerin, phellodendron leaf essential oil, Tween-80 and calcium chloride can be better homogenized and stirred.

[0078] Step 4: Degassing the prepared film-forming liquid for a period of 0.5 to 2 hours to remove bubbles and improve the quality of the film, then pouring the degassed film-forming liquid into a mold and drying it for 5 hours until a film is formed;

[0079] Specifically, on the basis of step 3, the air in the container is extracted by a vacuum pump 50, so that the prepared film-forming liquid can be degassed, and then the degassed film-forming liquid is poured into the mold, and the mold is placed on the electric heating plate 22. At this time, the film-forming liquid in the mold can be dried by the electric heating plate 22;

[0080] Step 5: Conduct a series of physical and chemical property tests on the prepared film, such as thickness measurement, tensile performance test, swelling coefficient determination, dissolution time test, infrared spectroscopy analysis and scanning electron microscope microstructure observation.

[0081] In summary, the present invention adopts essential oil extracted from the leaves of Clausena lansium (Lour.) Skeels, which contains sesquiterpenes, olefins and other volatile bioactive compounds. Experiments have shown that the essential oil has a significant inhibitory effect on pathogenic bacteria such as Staphylococcus aureus, Candida albicans, Streptococcus mutans and Escherichia coli; at the same time, chitosan, as a polysaccharide converted from natural chitin, has excellent biocompatibility, degradability and good film-forming properties, and has a certain antibacterial activity. The synergistic effect of the two effectively makes up for the shortcomings of a single component in terms of antibacterial persistence and stability. In addition, the composite system of the present invention utilizes the encapsulation and sustained-release effect of chitosan on the pomelo leaf essential oil, thereby prolonging the antibacterial time of the essential oil in the use environment, achieving the dual goals of "immediate and efficient antibacterial effect" and "long-lasting sustained-release antibacterial effect", and meeting the needs of practical applications for long-term antibacterial effect; more importantly, all the raw materials used are natural extracts and biodegradable polymer materials, which not only greatly reduces the toxicity, drug resistance and environmental pollution problems that may be caused by traditional chemical preservatives and metal antibacterial agents, but also can be biodegraded after use, which fully complies with the concepts of green, environmental protection and sustainable development.

[0082] Based on the above, it can be seen that the present invention is also applicable to the following aspects including but not limited to:

[0083] The antibacterial film technology of the present invention is applicable to food preservation, oral antibacterial and other related fields. In terms of food preservation, by inhibiting the growth of microorganisms such as Staphylococcus aureus and Escherichia coli, the shelf life of food can be extended and the use of traditional preservatives can be reduced; in oral care, the antibacterial film can be made into oral films, edible slices or sustained-release capsules to prevent the formation of dental plaque and reduce the risk of diseases such as periodontitis and oral ulcers; in addition, with its good flexibility and sustained-release effect, the technology can also be used for medical dressings, wound protection and fruit and vegetable coatings to achieve multiple functions such as wound infection resistance and fruit and vegetable preservation.

[0084] A device for preparing an edible yellow calendula leaf essential oil chitosan antibacterial film comprises a base 10 and a container, wherein a first block 221 is fixedly installed at the bottom of the container, a magnetic stirrer with a drying function is arranged on the top left side of the base 10, a homogenizer with a water bath function is arranged on the top right side of the base 10, and a degassing component is arranged on the homogenizer.

[0085] The magnetic stirrer includes: a magnetic stirrer body 20, a first annular plate 21, an electric heating plate 22, a first block 221, a first hollow circular plate 23, a first L-shaped rod 24, a first support plate 25, a first cylinder 26, a first sealing plate 27, a first rotating rod 28, a magnet 29, and a first temperature sensor 291;

[0086] The magnetic stirrer body 20 is fixedly mounted on the top left side of the base 10, the first annular plate 21 is fixedly mounted on the top outer side of the magnetic stirrer body 20, the electric heating plate 22 is fixedly mounted on the top inner side of the magnetic stirrer body 20, and the first block 221 is inserted on the top of the electric heating plate 22, the first hollow circular plate 23 is fixedly mounted on the top of the inner cavity of the first annular plate 21, and the inner cavity of the first hollow circular plate 23 is provided with a container, the side of the first annular plate 21 is fixedly mounted with a first support plate 25 through a first L-shaped rod 24, the first cylinder 26 is fixedly mounted on the top of the first support plate 25, the piston rod of the first cylinder 26 is fixedly mounted with a first sealing plate 27, and the first sealing plate 27 can contact the container, the first rotating rod 28 is fixedly mounted on the bottom of the first sealing plate 27, the bottom end of the first rotating rod 28 is rotatably connected to the magnet 29 through a bearing, and the first temperature sensor 291 is fixedly mounted on the bottom of the first sealing plate 27.

[0087] The homogenizer includes: a second annular plate 30 with water in its inner cavity, a bearing plate 31, a second hollow circular plate 32, a heat exchange tube 33, a pipe 34 with a valve thereon, a first one-way valve 341, a second L-shaped rod 35, a second support plate 36, a second cylinder 37, a servo motor 38, a second sealing plate 39, a second rotating rod 391, a stirring tube 392, a second one-way valve 393, a second temperature sensor 394, an air pump 40, an air outlet pipe 41, and a flow slot 42;

[0088] The second annular plate 30 is fixedly mounted on the top right side of the base 10, and the electric heating tube is fixedly mounted on the inner wall of the second annular plate 30, the bearing plate 31 is fixedly mounted on the top right side of the base 10, and the bearing plate 31 is located in the inner cavity of the second annular plate 30, the first block 221 is inserted on the top end of the bearing plate 31, the second hollow circular plate 32 is fixedly mounted on the top end of the inner cavity of the second annular plate 30, and the inner cavity of the first hollow circular plate 23 is provided with a container, the end of the heat exchange tube 33 is fixedly mounted on the top end of the second hollow circular plate 32, and one end of the heat exchange tube 33 is provided with a one-way valve, the side of the second annular plate 30 is fixedly mounted with a second support plate 36 through a second L-shaped rod 35, the second cylinder 37 is fixedly mounted on the top of the second support plate 36, the piston rod of the second cylinder 37 is fixedly mounted with a servo motor 38 through a flange, the output shaft of the servo motor 38 is fixedly mounted with a second sealing plate 39, and the second sealing plate 39 can contact with the container, and the second rotating rod 391 is fixedly mounted on the bottom of the second sealing plate 39 , a stirring tube 392 is fixedly mounted on the side wall of the bottom end of the second rotating rod 391, and a second one-way valve 393 is provided at one end of the stirring tube 392, a second temperature sensor 394 is fixedly mounted on the bottom of the second sealing plate 39, an air pump 40 is fixedly mounted on the top right side of the second sealing plate 39, an air outlet pipe 41 is fixedly mounted on the air outlet end of the air pump 40, and one end of the air outlet pipe 41 is fixedly mounted on the side wall of the second rotating rod 391, a circulation groove 42 is opened in the second rotating rod 391, and the air outlet pipe 41 and the circulation groove 42 are connected, a pipeline 34 is fixedly mounted on the side wall of the first annular plate 21, and one end of the pipeline 34 is fixedly mounted on the side wall of the second annular plate 30, and a first one-way valve 341 is provided at one end of the pipeline 34; wherein, a sealing ring can be set between the first hollow circular plate 23 and the container as required, and a sealing ring can also be set between the second sealing plate 39 and the container as required, in addition, a fan will be set in the pipeline 34 as required, because it belongs to conventional technology, it will not be described in detail here.

[0089] The degassing assembly includes: a vacuum pump 50, an air inlet pipe 51;

[0090] A vacuum pump 50 is fixedly mounted on the left side of the top of the second support plate 36 , an air intake pipe 51 is fixedly mounted on the air intake end of the vacuum pump 50 , and one end of the air intake pipe 51 is disposed in the second support plate 36 .

[0091] Based on the above, the following experiments were conducted on the antibacterial film prepared above:

[0092] Antibacterial effect of yellow peel leaf essential oil:

[0093] Preparation of bacterial suspension: culture the activated bacteria at 37°C for 8-10 hours and the fungi at 37°C for 12-16 hours, then dilute with sterile water to 1×10^6 CFU / mL for later use.

[0094] 4 strains of bacteria (Candida albicans, Streptococcus mutans, Escherichia coli, Staphylococcus aureus), 100 μl of bacterial suspension was inoculated on solid culture medium, and then a disposable coating rod was used to evenly coat the surface of the culture medium and let stand for 30 minutes. Then the inoculated plate was divided into 4 areas, and holes were punched in each area using a punching method, with consistent pore size, and different concentrations of yellow peel leaf essential oil (100%, 75%, 50%, 25%) and different concentrations (100%, 75%, 50%) (Table 1 only presents 100% concentration) of positive control group (Candida albicans positive control group uses fluconazole, Staphylococcus aureus and Escherichia coli use gentamicin, and Streptococcus mutans uses penicillin), and the negative control group uses DMSO and sterile water to add to the designated wells of the plate, and then put it into an incubator and culture for 24 hours to observe the results, and use a vernier caliper to record the diameter of the inhibition zone. The results were repeated 3 times for each experimental group.

[0095] Results Fig.10 As shown in Table 1, the essential oil of the yellow peel leaf has different degrees of inhibition on the four test bacteria. According to the criteria for judging the inhibition zone: the diameter of the inhibition zone is less than 10mm, which is insensitive, between 10mm-15mm, which is moderately sensitive, between 15mm-20mm, which is highly sensitive, and greater than 20mm, which is extremely highly sensitive. Therefore, the yellow peel leaf essential oil of different concentrations (25%-100%) is extremely sensitive to Candida albicans and Streptococcus mutans with an inhibition diameter greater than 20mm, and the yellow peel leaf essential oil of 50% and above concentration is extremely sensitive to Staphylococcus aureus and Escherichia coli. They all showed good antibacterial effects compared with the positive control group of the same concentration. The negative control group DMSO and water had no inhibitory effect on the four bacteria. The results are shown in Table 1. Therefore, the yellow peel leaf essential oil has an inhibitory effect on the above-mentioned fungi and bacteria.

[0096] Table 1 Diameters of inhibition zones of different samples

[0097]

[0098]

[0099] Note: “—” indicates no inhibition zone is produced.

[0100] Among them, Fig.10 Among them, A is 100% concentration of Phellodendron chinense leaf essential oil; B is 75% concentration of Phellodendron chinense leaf essential oil; C is 50% concentration of Phellodendron chinense leaf essential oil; D is 25% concentration of Phellodendron chinense leaf essential oil; E is 100% concentration of positive control group; F is DMSO+sterile water.

[0101] Antibacterial properties of chitosan antibacterial film containing Huangpi leaf essential oil:

[0102] In order to evaluate the antibacterial efficacy of the chitosan antibacterial film of Phellodendron chinense essential oil, four representative microbial strains were selected in this study, including Streptococcus mutans, Candida albicans, Escherichia coli and Staphylococcus aureus. During the experiment, different types of strains were cultured in appropriate culture media.

[0103] First, prepare the Huangpi leaf essential oil chitosan antibacterial film. The specific method is as follows: weigh 2g of chitosan and dissolve it in 1% acetic acid solution to prepare a chitosan solution with a volume fraction of 2%, and stir it magnetically at 50°C for 2 hours until the chitosan is completely dissolved. Take 100mL of chitosan solution with a volume fraction of 2%, add 1.5g of gelatin, stir in a 50°C water bath for 30 minutes, and then add 1.5mL of glycerol, 0.4mL of Huangpi leaf essential oil, 0.5mL of Tween-80 and 0.3g of calcium chloride. Stir and mix at a speed of 10000r / min in a homogenizer for 5 minutes to prepare a Huangpi leaf essential oil chitosan antibacterial film liquid. Degas the film liquid in a vacuum defoaming barrel for 0.5 to 2.0 hours, and then place it in an oven for 5 hours. This method is consistent with the method described above.

[0104] Next, the prepared film was cut into 3×3 cm samples according to uniform specifications for later use. Under a sterile environment, 500 μL of bacterial suspension with a concentration of 1×10^6 CFU / mL was added to each test tube containing 500 μL of the corresponding culture solution, and the cut film samples were placed at the same time. The negative control group only added the same volume of culture solution and bacterial suspension, but no film samples were placed, and the other experimental conditions were kept consistent. Then, all treated samples were placed in a 37°C constant temperature incubator for incubation for 12 hours. After the incubation, each group of liquid samples was diluted 100 times, and 50 μL was taken and spread on the corresponding solid culture medium plate, and then all plates were placed in a 37°C constant temperature incubator for culture, and the growth of each strain was observed and recorded at different times, so as to evaluate the antibacterial effect of the yellow peel leaf essential oil chitosan antibacterial film on different strains.

[0105] The experimental results are as follows Fig.11 As shown in the figure, compared with the negative control group, the surviving bacteria of Candida albicans, Streptococcus mutans, Escherichia coli and Staphylococcus aureus in the experimental group co-cultured with the chitosan antibacterial film release liquid of the yellow peel leaf essential oil were significantly reduced. This result shows that the yellow peel leaf essential oil chitosan antibacterial film has significant antibacterial efficacy. Fig.11 A is the experimental group and B is the negative control group.

[0106] Although the present invention has been described above with reference to the embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed in the present invention may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for preparing an edible yellow peel leaf essential oil chitosan antibacterial film, characterized in that: The specific steps are as follows: Step 1: Add 2 g of chitosan to 1% acetic acid solution and stir at 50°C for 2 hours using a magnetic stirrer until the chitosan is completely dissolved to form a uniform solution; Step 2: Add 1.5 g of gelatin to 100 ml of 2% chitosan solution, heat to 50° C. in a water bath, and stir for 30 minutes to fully mix the gelatin and chitosan solution; Step 3: Add 1.5 ml of glycerol, 0.4 ml of Phellodendron chinense essential oil, 0.5 ml of Tween-80 and 0.3 g of calcium chloride to the mixture, and stir at a speed of 10,000 rpm for 5 minutes using a homogenizer to prepare a uniform chitosan-Phellodendron chinense essential oil composite membrane liquid; Step 4: Degas the prepared film-forming liquid for a period of 0.5 to 2 hours to remove bubbles and improve the quality of the film. The degassed film-forming liquid is then poured into a mold and dried for 5 hours until a film is formed.

2. A preparation device for an edible yellow peel leaf essential oil chitosan antibacterial film, characterized in that: The invention comprises a base (10) and a container, wherein a first block (221) is fixedly mounted on the bottom of the container, a magnetic stirrer with a drying function is arranged on the left side of the top of the base (10), and a homogenizer with a water bath function is arranged on the right side of the top of the base (10), and a degassing component is arranged on the homogenizer.

3. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 2, characterized in that, The magnetic stirrer comprises: A magnetic stirrer body (20), wherein the magnetic stirrer body (20) is fixedly mounted on the top left side of the base (10); A first annular plate (21), wherein the first annular plate (21) is fixedly mounted on the top outer side of the magnetic stirrer body (20); An electric heating plate (22), the electric heating plate (22) is fixedly mounted on the inner side of the top of the magnetic stirrer body (20), and the first block (221) is inserted on the top of the electric heating plate (22); A first hollow circular plate (23), wherein the first hollow circular plate (23) is fixedly mounted on the top end of the inner cavity of the first annular plate (21), and a container is provided in the inner cavity of the first hollow circular plate (23).

4. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 3, characterized in that: The magnetic stirrer also includes: A first support plate (25), the first support plate (25) being fixedly mounted on the side surface of the first annular plate (21) via a first L-shaped rod (24); A first cylinder (26), the first cylinder (26) being fixedly mounted on the top of the first support plate (25); A first sealing plate (27), the first sealing plate (27) is fixedly mounted on the piston rod of the first cylinder (26), and the first sealing plate (27) is capable of contacting the container.

5. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 4, characterized in that: The magnetic stirrer also includes: A first rotating rod (28), wherein the first rotating rod (28) is fixedly mounted on the bottom of the first sealing plate (27); A magnet (29), wherein the bottom end of the first rotating rod (28) is rotatably connected to the magnet (29) via a bearing; A first temperature sensor (291), wherein the first temperature sensor (291) is fixedly mounted on the bottom of the first sealing plate (27).

6. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 3, characterized in that: The homogenizer comprises: A second annular plate (30) for water is provided in its inner cavity, the second annular plate (30) is fixedly mounted on the top right side of the base (10), and an electric heating pipe is fixedly mounted on the inner wall of the second annular plate (30); A bearing plate (31), the bearing plate (31) is fixedly mounted on the top right side of the base (10), and the bearing plate (31) is located in the inner cavity of the second annular plate (30), and the first block (221) is inserted on the top of the bearing plate (31); A second hollow circular plate (32), wherein the second hollow circular plate (32) is fixedly mounted on the top end of the inner cavity of the second annular plate (30), and a container is provided in the inner cavity of the first hollow circular plate (23); A heat exchange tube (33), the end of which is fixedly mounted on the top end of the second hollow circular plate (32), and a one-way valve is provided at one end of the heat exchange tube (33).

7. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 6, characterized in that: The homogenizer also includes: A second support plate (36), the second support plate (36) being fixedly mounted on the side surface of the second annular plate (30) via a second L-shaped rod (35); a second cylinder (37), the second cylinder (37) being fixedly mounted on the top of the second support plate (36); A servo motor (38), wherein the piston rod of the second cylinder (37) is fixedly mounted with the servo motor (38) via a flange; A second sealing plate (39), the second sealing plate (39) is fixedly mounted on the output shaft of the servo motor (38), and the second sealing plate (39) is capable of contacting the container; A second rotating rod (391), the second rotating rod (391) is fixedly mounted on the bottom of the second sealing plate (39); A stirring tube (392), the stirring tube (392) is fixedly mounted on the side wall of the bottom end of the second rotating rod (391), and a second one-way valve (393) is provided at one end of the stirring tube (392); A second temperature sensor (394), the second temperature sensor (394) is fixedly mounted on the bottom of the second sealing plate (39).

8. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 7, characterized in that: The homogenizer also includes: An air pump (40), the air pump (40) being fixedly mounted on the top right side of the second sealing plate (39); An air outlet pipe (41), wherein the air outlet pipe (41) is fixedly mounted on the air outlet end of the air pump (40), and one end of the air outlet pipe (41) is fixedly mounted on the side wall of the second rotating rod (391); A circulation groove (42), wherein the circulation groove (42) is opened in the second rotating rod (391), and the air outlet pipe (41) and the circulation groove (42) are connected.

9. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 8, characterized in that: The homogenizer also includes: A pipe (34) with a valve is provided thereon, the pipe (34) is fixedly mounted on the side wall of the first annular plate (21), and one end of the pipe (34) is fixedly mounted on the side wall of the second annular plate (30); A first one-way valve (341), one end of the pipeline (34) is provided with a first one-way valve (341).

10. The preparation device of an edible yellow peel leaf essential oil chitosan antibacterial film according to claim 7, characterized in that: The degassing assembly comprises: A vacuum pump (50), the vacuum pump (50) is fixedly mounted on the left side of the top of the second support plate (36); An air intake pipe (51), wherein the air intake pipe (51) is fixedly mounted on the air intake end of the vacuum pump (50), and one end of the air intake pipe (51) is disposed in the second support plate (36).

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