CN113417074A

CN113417074A - Preparation method of antibacterial nanofiber membrane

Info

Publication number: CN113417074A
Application number: CN202110565305.7A
Authority: CN
Inventors: 刘芳; 王德宝; 孙芝兰; 吴海虹; 王道营; 孙远成; 严敏
Original assignee: Jiangsu Academy of Agricultural Sciences
Current assignee: Jiangsu Academy of Agricultural Sciences
Priority date: 2021-05-24
Filing date: 2021-05-24
Publication date: 2021-09-21

Abstract

The invention provides a preparation method of an antibacterial nanofiber membrane, and relates to the field of food preservation. The preparation method of the antibacterial nanofiber membrane is characterized by comprising the following steps of: preparing the antibacterial nanofiber membrane from the electrospinning membrane blending liquid containing 100-140g/L gelatin, 10-30g/L zein and 50-1000mg/L perillaldehyde by adopting an electrostatic spinning technology. The preparation method of the antibacterial nanofiber membrane is simple and low in cost, and the prepared nanofiber membrane has excellent safety, antibacterial activity, stability, ductility and higher tensile strength.

Description

Preparation method of antibacterial nanofiber membrane

Technical Field

The invention relates to the field of food preservation, in particular to a preparation method of an antibacterial nanofiber membrane.

Background

With the improvement of living standard, people gradually pursue diversification of health, nutrition and diet, and especially, the demand for fresh food such as fruits, vegetables, meat and aquatic products is increasing. Freshness of fresh food is an important indicator for consumers. Fresh food is subject to microbial spoilage during refrigeration and sale, resulting in short shelf life. Therefore, the development of antibacterial packaging materials is the key to guarantee the quality of fresh food and prolong the shelf life of food. However, the existing bacteriostatic nanofiber membrane cannot meet the requirements in the aspects of safety, stability and antibacterial performance.

Disclosure of Invention

The invention aims to provide a preparation method of an antibacterial nanofiber membrane, which is simple and low in cost, and the prepared nanofiber membrane has excellent safety, antibacterial activity, stability, ductility and higher tensile strength.

The purpose of the invention is realized by adopting the following technical scheme:

the preparation method of the antibacterial nanofiber membrane is characterized by comprising the following steps of:

preparing the antibacterial nanofiber membrane from the electrospinning membrane blending liquid containing 100-140g/L gelatin, 10-30g/L zein and 50-1000mg/L perillaldehyde by adopting an electrostatic spinning technology.

In the invention, the concentration of the perillaldehyde in the electrospun membrane blend liquid is 250-500 mg/L.

In the invention, the concentration of perillaldehyde in the electrospun membrane blend is 500 mg/L.

In the invention, the electrospun membrane blend liquid is prepared by the following method: sequentially dissolving gelatin and zein in a glacial acetic acid water solution with the volume percentage concentration of 70-85% to obtain gelatin-zein electrospinning solution; dissolving perillaldehyde in tween-80 to obtain perillaldehyde solution; adding the perillaldehyde solution into the gelatin-zein electrospinning solution to obtain the electrospinning film blending solution.

In the invention, the mass percentage concentration of the perillaldehyde in the perillaldehyde solution is 20-30%.

Has the advantages that: the raw materials of the gelatin and the zein of the antibacterial nanofiber membrane are both food grade, the preparation method is simple and easy to operate, the cost is low, and the prepared nanofiber membrane has excellent safety, antibacterial activity, stability, ductility and higher tensile strength and is an edible antibacterial nanofiber membrane.

Drawings

FIG. 1 shows the change of viable cell count of each membrane-packaged chicken breast stored at different times, wherein control is a control group (G/Z membrane).

FIG. 2 TVB-N as a function of storage time during storage of each film-wrapped chicken breast, where control is a control group (G/Z film).

FIG. 3 shows the viscosity of each of the electrospun membrane blend and the gelatin-zein electrospun solution, G/Z represents the control membrane, and G/Z/P (5:1:0.0025), G/Z/P (5:1:0.005), G/Z/P (5:1:0.01), G/Z/P (5:1:0.02) and G/Z/P (5:1:0.04) represent bacteriostatic

nanofiber membranes

1, 2, 3, 4 and 5, respectively.

FIG. 4 shows normal distribution diagrams of bacteriostatic nanofiber membranes and control membranes and fiber diameters, where A-F are

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5, respectively, G is the control membrane, and the abscissa of the normal distribution diagram is fiber Diamter (nm) and the ordinate is relative frequency (%).

FIG. 5 is an XRD diagram of the bacteriostatic nanofiber membrane and the control membrane, wherein gelatin and zein represent gelatin and zein respectively, G/Z represents the control membrane, and G/Z/P (5:1:0.0025), G/Z/P (5:1:0.005), G/Z/P (5:1:0.01), G/Z/P (5:1:0.02) and G/Z/P (5:1:0.04) represent

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5 respectively.

FIG. 6 is a DSC curve (A) and a TGA thermogravimetric curve (B) of the bacteriostatic nanofiber membrane and the control membrane, wherein G/Z represents the control membrane, and G/Z/P (5:1:0.0025), G/Z/P (5:1:0.005), G/Z/P (5:1:0.01), G/Z/P (5:1:0.02) and G/Z/P (5:1:0.04) represent the

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5 respectively.

FIG. 7 shows water contact angles of the bacteriostatic nanofiber membrane and a control membrane, G/Z represents the control membrane, and G/Z/P (5:1:0.0025), G/Z/P (5:1:0.005), G/Z/P (5:1:0.01), G/Z/P (5:1:0.02) and G/Z/P (5:1:0.04) represent bacteriostatic

nanofiber membranes

1, 2, 3, 4 and 5, respectively.

FIG. 8 shows the change of bacteriostatic activity of the bacteriostatic nanofiber membrane and the control membrane on Staphylococcus aureus and Salmonella, the abscissa shows the treatment time, the ordinate shows the total viable count, G/Z shows the control membrane, and G/Z/P (5:1:0.0025), G/Z/P (5:1:0.005), G/Z/P (5:1:0.01), G/Z/P (5:1:0.02) and G/Z/P (5:1:0.04) respectively show the

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5.

Detailed Description

The test strains and chemical kit instrument sources referred to in the following examples are as follows:

test strains: salmonella enteritidis H4 and Staphylococcus aureus G1 are target bacteria, and are separated, identified and provided from fresh chicken by livestock and poultry research institute of Processary institute of agriculture and sciences of Jiangsu province.

The main chemical reagents are as follows: nutrient broth culture medium, brain heart extract culture medium (BHI), purchased from Beijing road bridge technology, LLC; gelatin, available from Tianjin Kemi Euro reagent, Inc.; glacial acetic acid, available from Shanghai Aladdin Biotechnology Ltd; perillaldehyde (purity > 95%) purchased from Shanghai-derived leaf Biotech, Inc.; zein (bioreagent, Mw 22-24kDa, purity > 92%) was purchased from shanghai source leaf biotechnology limited.

The main apparatus comprises: EXSTAR series TG/DTA7200 thermogravimetric analyzer, SII Nano Technology Inc., Japan; DP30 electrospinning apparatus, tianjin cloud sail science & ltd; physica MCR301 rheometer, austria apopa; PE (ultra View VOX) rotating disk laser confocal microscope, platinum Elmer, USA; EVO-LS10 scanning Electron microscope, Calzeiss GmbH, Germany; microplate reader BioTek Instruments Inc., USA; nicolet iS50 fourier transform infrared spectrometer, sreisel ltd, usa; differential scanning calorimetry, TA ltd, usa; d2 phaser x-ray diffractometer, brueck, usa.

Example 1 comparison of bacteriostats

Dissolving 12.5g gelatin in 100mL acetic acid solution (80% v/v distilled water), stirring for 15 minutes on a magnetic stirrer at 50-55 deg.C to obtain clear and uniform solution; adding 2.5G of zein into the solution, magnetically stirring again for 15min at 50-55 ℃ until the solution is transparent to obtain gelatin-zein electrospinning solution, wherein the label is G/Z, and the membrane obtained by electrospinning is marked as a G/Z membrane. 50mg of perillaldehyde, thymol (abbreviated as T) and epsilon-polylysine (abbreviated as epsilon-PL) are respectively added into 100ml of G/Z solution, stirring is carried out for 24h at 20-25, 3 different electrostatic spinning solutions are obtained, which are respectively marked as G/Z/P, G/Z/T and G/Z/epsilon-PL, and membranes obtained after electrospinning are respectively marked as G/Z/P, G/Z/T and G/Z/epsilon-PL membranes. And the G/Z film without the antibacterial agent is used as a blank control, and the influences of the three antibacterial agents on the mechanical property and the physical and chemical properties of the film and the fresh-keeping effect of the chilled chicken breast are compared, so that the nanofiber film with good properties and fresh-keeping effect is screened out to serve as a potential application material of the food packaging film.

TABLE 1 mechanical Properties of G/Z/P, G/Z/T and G/Z/ε -PL films

	G/Z	G/Z/P	G/Z/T	G/Z/ε-PL
					Elongation (%)	33.27	39.10	35.71	36.48
Tensile strength (MPa)	1.86	2.88	2.64	1.88

In order to evaluate the application performance, the mechanical properties, the elongation at break and the tensile strength of the gelatin/zein nanofibers loaded with different antibacterial agents were tested and are shown in table 1. The elongation at break and tensile strength of the blank G/Z nanofiber membrane are 33.27% and 1.86MPa respectively. The mechanical property of the nanofiber film is improved to different degrees by loading three antibacterial agents, and the plasticity of the film is improved. As is clear from Table 1, the elongation and tensile strength of the G/Z/P film were the highest, and were 39.10% and 2.88MPa, respectively. The G/Z/P film is improved by 9.49 percent and 7.18 percent compared with the G/Z/T film and the G/Z/epsilon-PL film respectively. The tensile strength of the G/Z/P film is improved by 9.09% and 53.19% compared with the G/Z/T film and the G/Z/epsilon-PL film respectively. The above results show that perillaldehyde is more beneficial to improving the flexibility and ductility of the gelatin/corn alcohol nanofiber film compared with thymol and epsilon-polylysine.

Microorganisms that are contaminated during slaughter and processing are the major spoilage bacteria that grow rapidly and cause quality deterioration during storage of frozen meat and meat products. The chicken breast meat with the same quality is packaged by each film with the same area, stored at 4 ℃ for different time, and the viable count is detected. As shown in FIG. 6, the Total Viable Count (TVC) of the control group (G/Z membrane) increased significantly with the increase of the storage time, and reached 7.77Log (CFU/G) after 9 d. The TVC of the frozen chicken breasts packed with G/Z/P, G/Z/T and G/Z/epsilon-PL membrane was significantly lower than that of the control group. The result shows that the G/Z of the perillaldehyde, the thymol and the epsilon-polylysine have good bacteriostatic effect. The TVC of the G/Z/P, G/Z/T and G/Z/epsilon-PL films were 5.95, 6.61 and 7.41Log (CFU/G), respectively, at 12 days of storage, with the lowest TVC of the G/Z/P group. TVC determination further indicates that under the same load concentration, the preservation effect of the perillaldehyde nanofiber membrane on the frozen chicken breast is remarkably superior to that of thymol and polylysine, and the shelf life of the chicken breast for 6 days can be effectively prolonged.

TVB-N (volatile basic nitrogen) is a basic nitrogen-containing substance such as ammonia and amine generated by protein decomposition, and is one of important indexes of meat spoilage. Therefore, the change of TVB-N in the chicken breast storage process is detected. The results are shown in FIG. 2. It can be seen that the TVB-N content of each group increased during storage due to the decomposition of proteins by the putrescence bacteria. The TVB-N of the control group (G/Z film) is obviously increased along with the prolonging of the storage time and reaches 17.391.67mg/100G after 6 days, which exceeds the requirements of the Chinese livestock and poultry fresh meat sanitary standard (< 15mg/100G, GB 2707-2016). The TVB-N of the frozen chicken breast meat packaged with the nanofiber membrane is slowly increased, and the bacteriostatic ability is shown as G/Z/P > G/Z/T > G/Z/epsilon-PL. The TVBN content after the G/Z/P group is stored for 12 days is 15.55 mg/100G. Therefore, the measurement of TVB-N further supports the best antibacterial and preservation effects of the G/Z/P nanofiber film.

Therefore, the perillaldehyde fiber membrane is a better antibacterial agent. The effect of perillaldehyde concentration on the fiber membrane performance was investigated below.

Example 2 bacteriostatic nanofiber membranes

1. Preparation of antibacterial nanofiber membrane

Adding 2.5g of gelatin into 20mL of glacial acetic acid water solution with the volume percentage content of 80%, stirring for 0.5h in a water bath kettle at the temperature of 55 ℃ to dissolve the gelatin, then adding 0.5g of zein, stirring for 8min to dissolve the zein, and cooling to room temperature to obtain the gelatin-zein electrospinning solution. The tween-80 is used as a solvent to prepare 25 percent (mass percentage concentration) of perillaldehyde solution. Adding the perillaldehyde solution into the gelatin-zein electrospinning solution to prepare the electrospinning film blending solution with the perillaldehyde content of 62.5, 125, 250, 500 and 1000 mu g/mL.

Respectively carrying out electro-spinning on the electro-spinning membrane blend liquid by adopting a DP30 electro-spinning instrument (Tianjin Yunsfan science and technology Co., Ltd.), wherein the specific method comprises the following steps: the electrospun membrane blend was loaded into a 5ml syringe, which was connected to an 18G Luer-lock metal needle. The injection pump is connected with a high-voltage power supply. The electrospinning duration was 12 hours, and the system parameters were: the flow rate is 0.36mm/h, the distance from the blade tip to the collector electrode is 150mm, and the voltage is 22 Kv. A square grounded collector electrode was fixed at a suitable distance from the nozzle and the nanofibers were collected on a 25 x 25 aluminum foil.

And (3) carrying out electrospinning membrane on the gelatin-zein electrospinning solution by adopting the same method.

The membranes prepared by electrospinning the electrospinning film blend liquid with the perillaldehyde content of 62.5, 125, 250, 500 and 1000 mug/mL are respectively marked as G/Z/P (5:1:0.0025), G/Z/P (5:1:0.005), G/Z/P (5:1:0.01), G/Z/P (5:1:0.02) and G/Z/P (5:1:0.04), and are sequentially marked as

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5, as shown in Table 2. And the film prepared from the gelatin-zein electro-spinning solution not loaded with perillaldehyde is a control film, is marked as G/Z and is a control of the film.

TABLE 2 Perilla aldehyde content in antibacterial nanofiber membranes

2. Performance detection method of each antibacterial nanofiber membrane

(1) Characterization of electrospun membranes

Characterization of properties of the electrospun blend: the rheological properties of the electrospinning film blend liquid and the gelatin-zein electrospinning liquid under the static shearing action are characterized by adopting a Paar Physica MCR301 stress control rheometer, wherein the diameter of a flat plate is 20mm, and the testing temperature is controlled at (25 +/-5) DEG C.

Infrared spectrum test, wherein the detection samples are

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5 and a control membrane, and the detection method comprises the following steps: the wavelength range is the middle infrared (4000-600 cm)^-1) At 4cm^-1The spectral resolution of (a) is cumulatively scanned 32 times for each spectrum.

Differential scanning calorimetry, adopting a differential scanning calorimeter (American TA) to determine DSC parameters of the

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5 and the control membrane: glass transition temperature (Tg) and melting point (Tm). The detection method comprises the following steps: the DSC parameters were measured by placing 4mg of the sample in a covered aluminum sample holder and heating to 250 ℃ at a heating rate of 10 ℃/min under a nitrogen atmosphere.

X-ray diffraction (XRD): antibacterial nanofiber by using Bruker D8 advanced X-ray

diffraction analyzerVitamin membranes

1, 2, 3, 4, 5 and control membranes were analyzed. The detection conditions were as follows: voltage of 20kV, current of 5mA, Ka

The scanning speed is 4 DEG/min, the step length is 0.02 DEG, and the scanning range is5 DEG to 40 deg.

Scanning electron microscopic analysis, namely analyzing the

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5 and a control membrane by adopting a scanning electron microscope. The surface of each sample was treated with gold (25mA, 40s) spray, the acceleration voltage during scanning was 10kV, the size and distribution of the fiber diameter were counted by Image J software, and n was 100.

And (3) thermogravimetric analysis, namely heating the

antibacterial nanofiber membranes

1, 2, 3, 4 and 5 to 600 ℃ gradually at a heating rate of 10 ℃/min under a nitrogen atmosphere (gas flow rate of 15mL/min) from room temperature, and measuring the thermogravimetric change parameters of the

antibacterial nanofiber membranes

1, 2, 3, 4 and 5 and the control membrane by using a TGA Q50 (American TA) thermogravimetric analyzer.

And (3) testing a static water contact angle, namely cutting the

bacteriostatic nanofiber membranes

1, 2, 3, 4 and 5 and the control membrane into sizes of 2cm multiplied by 2cm respectively, fixing the sizes on a glass slide, and reading after regulating the sizes of liquid drops to be stable for 5 s.

(2) Perilla aldehyde loaded electrospinning membrane bacteriostasis determination method

Measuring the bacteriostatic quantity of the electrospun membrane: centrifuging 7mL of staphylococcus aureus liquid in logarithmic phase (cultured for 5-7h at 37 ℃) for 10min at 6000r/min, washing thallus precipitates for 2-3 times by using 0.85% physiological saline, adding 7mL of sterilized physiological saline, shaking and uniformly mixing, then respectively sucking 1mL of the sterilized bacterial liquid and adding the washed bacterial liquid into 7 sterilized 2mL centrifuge tubes, respectively adding 25mg of

bacteriostatic nanofiber membranes

1, 2, 3, 4, 5 and 6 or a control membrane into each centrifuge tube, processing for 0, 0.5, 2 and 4h at room temperature, then carrying out gradient dilution on the bacterial liquid, then carrying out plate inversion counting, and inspecting the inhibitory effect of each bacteriostatic nanofiber membrane and the control membrane on staphylococcus aureus at different time. In addition, the salmonella is adopted to replace staphylococcus aureus, and the inhibition effect of each bacteriostatic nanofiber membrane and each control membrane on the salmonella is observed at different time.

3 results of Performance testing

(1) Loading of perillaldehyde electrospinning liquid with different concentrations for rheological mechanical change

The shear rheological reaction of each electro-spinning membrane blend liquid and the gelatin-zein electro-spinning liquid loads the difference of the viscosities of the perillaldehyde blend liquids with different concentrations, and the change of the viscosity of the electro-spinning membrane blend liquid has important influence on the fiber diameter and the spinning stability of the electro-spinning membrane. The results are shown in fig. 3, which shows that the viscosity of the electrospun membrane blend increases with increasing perillaldehyde loading concentration.

(2) Electric spinning membrane form loaded with perillaldehyde with different concentrations and fiber diameter

The addition of the perillaldehyde changes the action mode between the gelatin and the zein, and the diameters of the nanofibers of all the bacteriostatic nanofiber membranes loaded with the perillaldehyde are smaller than those of the control membranes not loaded with the perillaldehyde. As can be seen from fig. 4, the diameter of the bacteriostatic nanofiber membrane becomes thicker as the loading concentration of perillaldehyde increases. But when the concentration of the perillaldehyde is increased to 500 mug/mL, the diameter of the bacteriostatic nanofiber membrane is increased to the maximum; when the concentration of the perillaldehyde is 1000 mug/mL, the diameter of the bacteriostatic nanofiber membrane is reduced to 63nm, and the difficulty of fiber membrane spinning is increased at the moment. Therefore, when the perillaldehyde concentration is 500 mug/mL, the perillaldehyde concentration becomes the critical concentration of the perillaldehyde in the bacteriostatic nanofiber membrane.

(3) Infrared spectroscopic analysis of electrospun membrane loaded with perillaldehyde with different concentrations

The results of comparison of gelatin, zein and electrospun fibers loaded with perillaldehyde with different concentrations under infrared spectroscopy show that the gelatin, zein and bacteriostatic nanofiber membranes have similar characteristic peaks but have certain transmittance difference. With the increase of the perillaldehyde concentration, the effects among the gelatin, the zein and the perillaldehyde are changed. The infrared spectrum analysis result shows that the addition of perillaldehyde increases intermolecular actions such as hydrogen bonds and the like among the perillaldehyde and the perillaldehyde. The gradually increased apparent density of the bacteriostatic nanofiber membrane reflects the intermolecular action degree of the three. The above results indicate that the force of intermolecular hydrogen bonding is strongest when the load is 500. mu.g/mL.

(4) XRD analysis of bacteriostatic nanofiber membrane loaded with perillaldehyde with different concentrations

As can be seen from fig. 5, the bacteriostatic nanofiber membrane has two diffraction peaks with different intensities at about 20 ° and 28 ° as the control membrane, while the gelatin and zeal nanofiber membrane has only one peak at 20-30 °. The results show that the gel, zein and violet aldehyde have good compatibility and interaction in the nanofiber membrane. G/Z/P-250 and G/Z/P-500 show broad peaks around 20 degrees, and have higher intensity, which indicates that strong intermolecular and intramolecular hydrogen bonds are generated. This result confirms the FTIR findings. Therefore, when the loading concentration of the perillaldehyde is within the range of 250-500 mu g/mL, the nanofiber is favorably changed from disorder to order, and the crystallinity is improved.

(5) Thermal analysis of electrospun membrane loaded with perillaldehyde with different concentrations

The thermal stability and degradation performance of the bacteriostatic nanofiber membrane were investigated by DSC (differential scanning calorimetry) and TGA (thermogravimetric) analysis. The results (fig. 6) show that changes in perillaldehyde concentration alter the interaction of gelatin, zein and perilla. The antibacterial nanofiber membranes have weak heat peaks at 202.91 ℃ and 216.16 ℃, and the Tm (melting point temperature) of the

antibacterial nanofiber membranes

4 and 5 is 215.67 ℃ and 216.16 ℃ respectively, which are higher than those of other materials. The Tm values of the other three bacteriostatic nanofiber membranes are not obviously different from those of the control membrane, which shows that the perillaldehyde not less than 250 mug/mL can improve the thermal stability of the nanofiber membranes.

(6) Supporting different concentrations of perillaldehyde electrospun membrane contact angles

Zein has a structure with a high proportion of hydrophobic groups, especially hydrophobic sulfur-containing amino acids. Gelatin and zein molecules in the bacteriostatic nanofiber membrane form hydrogen bonds through hydrophilic groups, and then a more hydrophobic surface is formed. As can be seen from fig. 7, the contact angle of the bacteriostatic nanofiber membrane gradually increases with the increase of the loading concentration of perillaldehyde; and under the condition of not less than 100 mu g/mL, the contact angle of the bacteriostatic nanofiber membrane is higher than that of the control membrane, which shows that the higher concentration of perillaldehyde can increase the relative proportion of hydrophobic groups and reduce the water absorption of the surface of the fiber membrane.

(7) Bacteriostatic activity

As can be seen from fig. 8, after the bacteriostatic nanofiber membrane treated two strains of bacteria for 2 hours, the decrease of the viable count of staphylococcus aureus and salmonella in each group except the

bacteriostatic nanofiber membranes

4 and 5 was reduced, and the difference was not significant even after 4 hours. And the staphylococcus aureus and salmonella of the

bacteriostatic nanofiber membranes

4 and 5 are reduced to the range of 5.0-5.2 log (CFU/mL), and the difference is not significant. By comparing the reduction rate of the two strains after 4 hours of treatment, the inhibition effect of the antibacterial nanofiber membrane on the intestinal streptococcus is proved to be stronger than that of staphylococcus aureus.

In conclusion, the bacteriostatic nanofiber membrane 5 loaded with the perillaldehyde with the concentration of 500 mug/mL can be used as an ideal antibacterial package.

Claims

1. The preparation method of the antibacterial nanofiber membrane is characterized by comprising the following steps of:

the antibacterial nanofiber membrane is prepared from an electrospinning membrane blending solution containing 120-130g/L gelatin, 20-30g/L zein and 50-1000mg/L perillaldehyde by an electrospinning technology.

2. The preparation method according to claim 1, wherein the perillaldehyde concentration in the electrospun membrane blend is 250-500 mg/L.

3. The preparation method according to claim 1 or 2, wherein the concentration of perillaldehyde in the electrospun membrane blend is 500 mg/L.

4. The preparation method according to claim 3, wherein the electrospun membrane blend is prepared by the following method: sequentially dissolving gelatin and zein in a glacial acetic acid water solution with the volume percentage concentration of 70-85% to obtain gelatin-zein electrospinning solution; dissolving perillaldehyde in tween-80 to obtain perillaldehyde solution; adding the perillaldehyde solution into the gelatin-zein electrospinning solution to obtain the electrospinning film blending solution.

5. The method according to claim 4, wherein the perillaldehyde solution has a perillaldehyde concentration of 20-30% by mass.