Preparation method of fructus forsythiae extract and application of fructus forsythiae extract in shampoo

Abstract

The invention relates to the technical field of fructus forsythiae extracts, in particular to a preparation method of a fructus forsythiae extract and application of the fructus forsythiae extract in shampoo, and the preparation method of the fructus forsythiae extract comprises the following steps: S1, pretreatment; s2, performing enzymolysis treatment; s3, microwave extraction; and S4, centrifugal purification. According to the method, the improved emulsion with the vitamin C-citric acid buffer solution as a water phase and the sunflower lecithin and the nonionic emulsifier as the compound emulsifier is used for low-temperature soaking treatment of the fructus forsythiae fruits, a brand-new extraction system is formed, the forsythin and the forsythiaside A in the fructus forsythiae can be effectively extracted, and the loss of the forsythin and the forsythiaside A can be reduced.

Description

Technical Field

[0001] This invention relates to the field of forsythia extract technology, specifically to a method for preparing forsythia extract and its application in shampoo. Background Technology

[0002] Forsythia is a shrub belonging to the genus Forsythia in the family Oleaceae. The medicinal part of Forsythia is mainly its dried fruit. Depending on the harvesting time, it is divided into green forsythia (immature fruit) and old forsythia (mature fruit). Although they are from the same genus and both are rich in key active ingredients such as forsythoside and forsythoside A, their medicinal effects differ significantly. Green forsythia has a higher content of forsythoside A and is richer in volatile oils, making it more effective in clearing heat and detoxifying, as well as antibacterial and anti-inflammatory effects. Old forsythia, on the other hand, has a higher degree of lignification and a higher proportion of phenolic acids, making it better at dispersing wind-heat and reducing swelling.

[0003] CN119185406A discloses a Forsythia suspensa extract and its preparation method. This method involves pretreatment by simmering Forsythia suspensa in water. However, this method can destroy some of the active ingredients in Forsythia suspensa due to the high-temperature simmering, reducing the activity and yield of the extract. Furthermore, this method uses only cellulase, pectinase, and saccharifying enzymes, which is a relatively limited selection and insufficient for the breakdown of the Forsythia suspensa cell wall and the release of its active ingredients. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing Forsythia suspensa extract and its application in shampoo, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a Forsythia suspensa extract, wherein the preparation method of the Forsythia suspensa extract includes the following steps: S1. Pretreatment: Forsythia fruit is placed in a modified emulsion and subjected to ultrasonic treatment at 35-45 kHz at 32-38℃. After soaking for 30-40 min, it is removed and vacuum dried at 50-54℃ and a vacuum degree of -0.08--0.09 MPa until the moisture content is ≤5%. The powder is then pulverized through a 60-100 mesh sieve to obtain Forsythia powder. The modified emulsion contains 0.3 wt%-0.5 wt% vitamin C, 0.2 wt%-0.4 wt% sunflower lecithin, and 0.015 wt%-0.050 wt% nonionic emulsifier. S2. Enzymatic hydrolysis: Add disodium hydrogen phosphate-citric acid buffer solution with a material-to-liquid ratio of 1:22-28 g / mL and a pH of 5.0-5.5 to the Forsythia powder, and add 1.2%-1.8% (by weight) of a complex enzyme to the Forsythia powder. Stir and hydrolyze at 44-48℃ and 180-240 rpm for 100-120 min, then inactivate the enzyme at 98-100℃ for 8-12 min, and cool to room temperature to obtain an enzymatic hydrolysis mixture. The complex enzyme consists of cellulase, pectinase, arabinosidase and β-glucosidase in a mass ratio of 2:1:0.5:1.5. S3. Microwave extraction: Add an extraction solvent with a material-to-liquid ratio of 1:25-30 mL / g to the enzymatic hydrolysis mixture, and perform co-extraction at a microwave power of 350-450W, an ultrasonic frequency of 40-50 kHz, and a temperature of 58-65℃ for 20-30 min. Then centrifuge at 6000-7000 r / min for 15-20 min, and take the supernatant to obtain the crude extract. The extraction solvent is a mixture of a eutectic solvent and 70 vol% ethanol at a volume ratio of 1:3-4. S4. Centrifugal purification: Place the crude extract in a high-speed centrifuge and centrifuge at 8000-10000 r / min for 20-25 min. Pass the supernatant after centrifugation through a polyethersulfone ultrafiltration membrane with a molecular weight cutoff of 3-5 kDa and filter at an operating pressure of 0.12-0.15 MPa and a temperature of 30-35℃ to obtain the Forsythia extract.

[0006] Optionally, the forsythia fruit is the green forsythia fruit produced by 3- to 5-year-old forsythia plants, and the harvesting time is from late July to late August.

[0007] Optionally, the preparation method of the modified emulsion includes the following steps: adding vitamin C to deionized water and stirring until completely dissolved to obtain a VC solution; adjusting the pH of the VC solution to 5.0-5.5 with a 1 mol / L citric acid solution; adding sunflower lecithin and a non-ionic emulsifier to the VC solution in sequence, and then ultrasonically emulsifying at 20-30 kHz for 12-18 min to obtain the modified emulsion.

[0008] Optionally, the nonionic emulsifier is composed of glyceryl monostearate and Tween 80 in a mass ratio of 1:1.

[0009] Optionally, the cellulase activity is ≥5000 U / g, the pectinase activity is ≥3000 U / g, the arabinosidase activity is ≥3000 U / g, and the β-glucosidase activity is ≥20000 U / g.

[0010] Optionally, the eutectic solvent is a choline chloride-propylene glycol eutectic solvent or a choline chloride-glycerol eutectic solvent, wherein the molar ratio of choline chloride to propylene glycol and the molar ratio of choline chloride to glycerol are both 1:2.

[0011] The present invention provides the following technical solution: the application of the above-mentioned Forsythia suspensa extract in shampoo, wherein the amount of Forsythia suspensa extract added is 1% to 3% of the total mass of the shampoo.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention uses a modified emulsion with vitamin C-citric acid buffer as the aqueous phase and sunflower lecithin and nonionic emulsifier as a composite emulsifier for low-temperature soaking treatment of Forsythia fruit, forming a brand-new extraction system that can effectively extract forsythoside A and forsythoside A from Forsythia, while reducing the loss of forsythoside A and forsythoside A. 2. The vitamin C in the improved emulsion of the present invention is acidic. The system is first adjusted to pH 5.0-5.5 with citric acid, which not only seamlessly connects with the subsequent enzymatic hydrolysis step, but also moderately reduces the polarity of forsythoside and forsythoside A, making them easier to dissolve from the cell wall. At the same time, alkaline conditions are avoided, and the risk of glycoside bond cleavage or ester bond hydrolysis is completely eliminated. 3. The Forsythia extract prepared by this invention can effectively inhibit Malassezia at the corresponding concentrations, and has the potential to be applied to scalp care. It helps to improve scalp folliculitis, seborrheic dermatitis and dandruff caused by excessive proliferation of Malassezia. At the same time, it can be used as a scalp care ingredient to help maintain the scalp microecological balance and can be applied to shampoos. Attached Figure Description

[0013] Figure 1 A photograph of the Forsythia extract prepared in Example 1 of this invention; Figure 2 This is the standard curve of forsythoside in Experimental Example 1 of this invention; Figure 3 This is the standard curve of forsythoside A in Experimental Example 1 of this invention. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Example 1 This invention provides a forsythia extract, the preparation method of which includes the following steps: S1. Pretreatment: Forsythia fruit was placed in a modified emulsion and subjected to ultrasonic treatment at 35℃ and 40 kHz for 35 min. After soaking, it was removed and vacuum dried at 52℃ and -0.085 MPa until the moisture content was ≤5%. The powder was then pulverized and passed through an 80-mesh sieve to obtain Forsythia powder. The modified emulsion contained 0.4 wt% vitamin C, 0.3 wt% sunflower lecithin, and 0.035 wt% nonionic emulsifier. The nonionic emulsifier consisted of glyceryl monostearate and Tween 80 in a mass ratio of 1:1. The modified emulsion was prepared by adding vitamin C to deionized water and stirring until completely dissolved to obtain a VC solution. The pH of the VC solution was adjusted to 5.2 with 1 mol / L citric acid solution. Sunflower lecithin and nonionic emulsifier were added to the VC solution in sequence, and then ultrasonically emulsified at 25 kHz for 15 min to obtain the modified emulsion. S2. Enzymatic hydrolysis: Add disodium hydrogen phosphate-citric acid buffer solution with a material-to-liquid ratio of 1:25 g / mL and a pH of 5.2 to the Forsythia powder, and add 1.5% of the Forsythia powder mass of a complex enzyme, which consists of cellulase, pectinase, arabinosidase and β-glucosidase in a mass ratio of 2:1:0.5:1.5. Stir and hydrolyze at 46℃ and 200 rpm for 110 min, then inactivate the enzyme at 99℃ for 10 min, and cool to room temperature to obtain the enzymatic hydrolysis mixture. S3. Microwave extraction: Add an extraction solvent with a material-to-liquid ratio of 1:28 mL / g to the enzymatic hydrolysis mixture. Perform co-extraction at a microwave power of 400W, an ultrasonic frequency of 45 kHz, and a temperature of 60℃ for 25 min. Then centrifuge at 6500 r / min for 18 min and collect the supernatant to obtain the crude extract. The extraction solvent is a mixture of a eutectic solvent and 70 vol% ethanol at a volume ratio of 1:3.5. The eutectic solvent is a choline chloride-propylene glycol eutectic solvent with a molar ratio of choline chloride to propylene glycol of 1:2. S4. Centrifugal purification: Place the crude extract in a high-speed centrifuge and centrifuge at 9000 r / min for 22 min. Pass the supernatant after centrifugation through a polyethersulfone ultrafiltration membrane with a molecular weight cutoff of 4 kDa and filter at an operating pressure of 0.13 MPa and a temperature of 32℃ to obtain the Forsythia extract.

[0016] Example 2 This invention provides a forsythia extract, the preparation method of which includes the following steps: S1. Pretreatment: Forsythia fruit was placed in a modified emulsion and subjected to ultrasonic treatment at 32℃ and 45 kHz. After soaking for 40 min, it was removed and vacuum dried at 50℃ and -0.08 MPa until the moisture content was ≤5%. The powder was then pulverized through a 60-mesh sieve to obtain Forsythia powder. The modified emulsion contained 0.3 wt% vitamin C, 0.2 wt% sunflower lecithin, and 0.015 wt% nonionic emulsifier. The nonionic emulsifier consisted of glyceryl monostearate and Tween 80 in a mass ratio of 1:1. The modified emulsion was prepared by adding vitamin C to deionized water and stirring until completely dissolved to obtain a VC solution. The pH of the VC solution was adjusted to 5.0 with 1 mol / L citric acid solution. Sunflower lecithin and nonionic emulsifier were added to the VC solution in sequence, and then ultrasonically emulsified at 20 kHz for 18 min to obtain the modified emulsion. S2. Enzymatic hydrolysis: Add disodium hydrogen phosphate-citric acid buffer solution with a material-to-liquid ratio of 1:22 g / mL and a pH of 5.0 to the Forsythia powder, and add 1.2% of the Forsythia powder mass of the complex enzyme. Stir and hydrolyze at 44℃ and 240 rpm for 120 min, then inactivate the enzyme at 98℃ for 12 min, and cool to room temperature to obtain the enzymatic hydrolysis mixture. The complex enzyme consists of cellulase, pectinase, arabinosidase and β-glucosidase in a mass ratio of 2:1:0.5:1.5. S3. Microwave extraction: Add an extraction solvent with a material-to-liquid ratio of 1:25 mL / g to the enzymatic hydrolysis mixture, and perform co-extraction at a microwave power of 350W, an ultrasonic frequency of 40 kHz, and a temperature of 58℃ for 30 min. Then, centrifuge at 6000 r / min for 20 min, collect the supernatant, and obtain the crude extract. The extraction solvent is a mixture of a eutectic solvent and 70 vol% ethanol at a volume ratio of 1:3. The eutectic solvent is a choline chloride-glycerol eutectic solvent with a molar ratio of choline chloride to glycerol of 1:2. S4. Centrifugal purification: Place the crude extract in a high-speed centrifuge and centrifuge at 8000 r / min for 25 min. Pass the supernatant after centrifugation through a polyethersulfone ultrafiltration membrane with a molecular weight cutoff of 3 kDa and filter at an operating pressure of 0.15 MPa and a temperature of 35℃ to obtain the Forsythia extract.

[0017] Example 3 This invention provides a forsythia extract, the preparation method of which includes the following steps: S1. Pretreatment: Forsythia fruit was placed in a modified emulsion and subjected to ultrasonic treatment at 38℃ and 45 kHz for 30 min. After soaking, it was removed and vacuum dried at 54℃ and -0.09 MPa until the moisture content was ≤5%. The powder was then pulverized and passed through a 100-mesh sieve to obtain Forsythia powder. The modified emulsion contained 0.5 wt% vitamin C, 0.4 wt% sunflower lecithin, and 0.050 wt% nonionic emulsifier. The nonionic emulsifier consisted of glyceryl monostearate and Tween 80 in a mass ratio of 1:1. The modified emulsion was prepared by adding vitamin C to deionized water and stirring until completely dissolved to obtain a VC solution. The pH of the VC solution was adjusted to 5.5 with 1 mol / L citric acid solution. Sunflower lecithin and nonionic emulsifier were added to the VC solution in sequence, and then ultrasonically emulsified at 30 kHz for 12 min to obtain the modified emulsion. S2. Enzymatic hydrolysis: Add disodium hydrogen phosphate-citric acid buffer solution with a material-to-liquid ratio of 1:28 g / mL and a pH of 5.5 to the Forsythia powder, and add 1.8% of the Forsythia powder mass of the complex enzyme. Stir and hydrolyze at 48℃ and 240 rpm for 100 min, then inactivate the enzyme at 100℃ for 8 min, and cool to room temperature to obtain the enzymatic hydrolysis mixture. The complex enzyme consists of cellulase, pectinase, arabinosidase and β-glucosidase in a mass ratio of 2:1:0.5:1.5. S3. Microwave extraction: Add an extraction solvent with a material-to-liquid ratio of 1:30 mL / g to the enzymatic hydrolysis mixture, and perform co-extraction at a microwave power of 450W, an ultrasonic frequency of 50 kHz, and a temperature of 65℃ for 20 min. Then, centrifuge at 7000 r / min for 15 min, collect the supernatant, and obtain the crude extract. The extraction solvent is a mixture of a eutectic solvent and 70 vol% ethanol at a volume ratio of 1:4. The eutectic solvent is a choline chloride-propylene glycol eutectic solvent with a molar ratio of choline chloride to propylene glycol of 1:2. S4. Centrifugal purification: Place the crude extract in a high-speed centrifuge and centrifuge at 10,000 r / min for 20 min. Pass the supernatant after centrifugation through a polyethersulfone ultrafiltration membrane with a molecular weight cutoff of 5 kDa and filter at an operating pressure of 0.15 MPa and a temperature of 30℃ to obtain the Forsythia extract.

[0018] Example 4 This invention provides a forsythia extract, the preparation method of which includes the following steps: S1. Pretreatment: Forsythia fruit was placed in a modified emulsion and subjected to ultrasonic treatment at 36 kHz at 36℃. After soaking for 36 min, it was removed and vacuum dried at 52℃ and a vacuum degree of -0.085 MPa until the moisture content was ≤5%. The powder was then pulverized and passed through an 80-mesh sieve to obtain Forsythia powder. The modified emulsion contained 0.4 wt% vitamin C, 0.3 wt% sunflower lecithin, and 0.035 wt% nonionic emulsifier. The nonionic emulsifier consisted of glyceryl monostearate and Tween 80 in a mass ratio of 1:1. The modified emulsion was prepared by adding vitamin C to deionized water and stirring until completely dissolved to obtain a VC solution. The pH of the VC solution was adjusted to 5.2 with 1 mol / L citric acid solution. Sunflower lecithin and nonionic emulsifier were added to the VC solution in sequence, and then ultrasonically emulsified at 25 kHz for 15 min to obtain the modified emulsion. S2. Enzymatic hydrolysis: Add disodium hydrogen phosphate-citric acid buffer solution with a material-to-liquid ratio of 1:26 g / mL and a pH of 5.2 to the Forsythia powder, and add 1.5% of the Forsythia powder mass of a complex enzyme, which consists of cellulase, pectinase, arabinosidase and β-glucosidase in a mass ratio of 2:1:0.5:1.5. Stir and hydrolyze at 46℃ and 220 rpm for 105 min, then inactivate the enzyme at 99℃ for 12 min, and cool to room temperature to obtain the enzymatic hydrolysis mixture. S3. Microwave extraction: Add an extraction solvent with a material-to-liquid ratio of 1:28 mL / g to the enzymatic hydrolysis mixture, and perform co-extraction at a microwave power of 400W, an ultrasonic frequency of 45 kHz, and a temperature of 62℃ for 24 min. Then, centrifuge at 6800 r / min for 16 min, collect the supernatant, and obtain the crude extract. The extraction solvent is a mixture of a eutectic solvent and 70 vol% ethanol at a volume ratio of 1:3.5. The eutectic solvent is a choline chloride-propylene glycol eutectic solvent with a molar ratio of choline chloride to propylene glycol of 1:2. S4. Centrifugal purification: Place the crude extract in a high-speed centrifuge and centrifuge at 9500 r / min for 22 min. Pass the supernatant after centrifugation through a polyethersulfone ultrafiltration membrane with a molecular weight cutoff of 4 kDa and filter at an operating pressure of 0.13 MPa and a temperature of 32℃ to obtain the Forsythia extract.

[0019] In Examples 1-4, the Forsythia fruits were the green fruits produced by 3-5 year old Forsythia plants, harvested from late July to late August. Cellulase activity was ≥5000 U / g, pectinase activity ≥3000 U / g, arabinosidase ≥3000 U / g, and β-glucosidase ≥20000 U / g.

[0020] Comparative Example 1 The difference between this embodiment and Example 1 is that the eutectic solvent used in S3 is a choline chloride-glycerol eutectic solvent, the molar ratio of choline chloride to glycerol is 1:2, and the volume ratio of the extraction solvent to 70 vol% ethanol is 1:3.

[0021] Comparative Example 2 The difference between this embodiment and embodiment 1 is that the amount of compound enzyme added in S2 is 1.2% of the mass of Forsythia powder, and the synergistic extraction temperature in step S3 is 58℃.

[0022] Comparative Example 3 The difference between this embodiment and Example 1 is that the mass ratio of the compound enzyme in S2 is adjusted to 2:1.2:0.5:1.5, and the synergistic extraction time in S3 is 30 min.

[0023] Comparative Example 4 The difference between this embodiment and Embodiment 1 is that deionized water is used instead of the modified emulsion.

[0024] Experimental Example 1: Content Test of Forsythoside and Forsythoside A Experiment content: 1. Solution preparation 50% methanol solution (extraction solvent) Measure 500 mL of methanol (chromatographic grade), add 500 mL of ultrapure water, mix well, and degas by sonication for 10 min (power 300W).

[0025] 0.1% phosphoric acid aqueous solution (mobile phase component) Accurately measure 1 mL of phosphoric acid, add 999 mL of ultrapure water, stir well, filter through a 0.22 μm organic phase filter membrane, and degas by ultrasonication for 1 min (power 300W).

[0026] Standard stock solution Forsythoside stock solution (1000 μg / mL): Accurately weigh 10.0 mg of forsythoside standard and place it in a 10 mL volumetric flask. Add 8 mL of 50% methanol solution and sonicate for 10 min (power 200W, temperature 30℃). After cooling to room temperature, dilute to the mark with 50% methanol and shake well.

[0027] Forsythoside A stock solution (1000 μg / mL): The preparation method is the same as forsythoside stock solution, except that forsythoside A standard is replaced.

[0028] Standard series concentration solutions Accurately measure 0.1 mL, 0.2 mL, 0.5 mL, 1.0 mL, and 2.0 mL of forsythoside A stock solution, respectively, and place them in 10 mL volumetric flasks. Dilute to the mark with 50% methanol and shake well to obtain a series of standard solutions with concentrations of 10 μg / mL, 20 μg / mL, 50 μg / mL, 100 μg / mL, and 200 μg / mL.

[0029] 2. Sample preparation Sample weighing: Take the Forsythia extracts prepared in Examples 1-4 and Comparative Examples 1-4 as samples, dry them in a vacuum drying oven at 60℃ for 2 h (vacuum degree -0.08 MPa), cool them to room temperature, accurately weigh 0.1000 g, and place them in a 50 mL volumetric flask.

[0030] Ultrasonic extraction: Add about 30 mL of 50% methanol solution to a volumetric flask, seal it, and place it in an ultrasonic extractor. Set the power to 300 W and the temperature to 40℃, and extract for 30 min.

[0031] Volume adjustment and filtration: After extraction, cool to room temperature and adjust the volume to 50 mL with 50% methanol solution, and shake well; take 5 mL of the above solution and filter it through a 0.22 μm organic phase filter membrane, discard the initial filtrate, and collect the subsequent filtrate as the sample test solution for analysis.

[0032] 3. Chromatographic conditions Chromatographic column: C18 reversed-phase column (250 mm × 4.6 mm, 5 μm).

[0033] Mobile phase: Acetonitrile-water (25:75, v / v) was used for the detection of forsythoside A; Acetonitrile-0.1% phosphoric acid aqueous solution (15:85, v / v) was used for the detection of forsythoside A.

[0034] Flow rate: 1.0 mL / min.

[0035] Column temperature: 30℃.

[0036] Detection wavelengths: forsythoside 277 nm, forsythoside A 330 nm.

[0037] Injection volume: 10 μL.

[0038] 4. Plotting the standard curve Inject 10 μL of each of the forsythoside A and forsythoside A series standard solutions in order of increasing concentration, and record the corresponding chromatograms and peak areas.

[0039] Using standard concentration (x, μg / mL) as the x-axis and peak area (y) as the y-axis, linear regression was performed using Excel to obtain the regression equation (y=ax+b) and the correlation coefficient (R²).2 ), requiring R 2 ≥0.999.

[0040] Please see Figure 2 , Figure 2 Forsythoside standard curve; please refer to Figure 3 , Figure 3 This is the standard curve for forsythoside A.

[0041] 5. Sample content determination Take 10 μL of the sample solution obtained in the sample preparation step, inject it under the set chromatographic conditions, and record the chromatogram and the peak areas corresponding to forsythoside and forsythoside A. Each sample is measured in triplicate, and the average peak area is used for calculation. Substitute the average peak area into the regression equation of the corresponding component to calculate the mass concentration (C, μg / mL) of forsythoside and forsythoside A in the sample solution.

[0042] According to the formula: The final contents of forsythoside and forsythoside A in the Forsythia suspensa extract were calculated, where V is the sample extraction volume and m is the sample weight. The data are recorded in Table 1.

[0043] Table 1. Results of the test on the content of forsythoside and forsythoside A

[0044] As shown in Table 1, the contents of forsythoside A and forsythoside A in Examples 1-4 were significantly higher than those in Comparative Example 4, indicating that the improved emulsion of the present invention can greatly improve the dissolution efficiency of the two active ingredients. Among them, Example 1 had the highest index and has priority for promotion.

[0045] Please see Figure 1 The Forsythia extract prepared in Example 1 is a brown liquid.

[0046] In conjunction with Example 1 and Comparative Example 1, even with changes in the type of eutectic solvent and adjustments in the ratio, the method of the present invention can still stably maintain a high dissolution rate of forsythoside and forsythoside A. In conjunction with Example 1 and Comparative Example 2, near the lower limits of the compound enzyme dosage and extraction temperature parameters, the method of the present invention can still achieve excellent dissolution effects of forsythoside and forsythoside A, demonstrating the stability and parameter tolerance of the process. In conjunction with Example 1 and Comparative Example 3, the compound enzyme ratio and extraction time determined in Example 1 are reasonable, providing a reliable benchmark for subsequent scale-up production.

[0047] Test Example 2 Antibacterial Test Experiment content: 1. Strains and Culture System Test strain: Malassezia (ATCC 14521).

[0048] Culture medium: Modified Dixon medium (containing 20 g / L malt extract, 10 g / L tryptone, 10 g / L yeast extract, 20 mL / L glycerol, 10 mL / L Tween 80, 5 mL / L olive oil, pH adjusted to 5.6) was used.

[0049] 2. Preparation of Forsythia extract solution The Forsythia suspensa extract prepared in Example 1 was diluted with sterile physiological saline to prepare Forsythia suspensa extract solutions with concentration gradients of 0.125 mg / mL, 0.25 mg / mL, 0.5 mg / mL, 1.0 mg / mL, 2.0 mg / mL, 4.0 mg / mL, 8.0 mg / mL, and 16.0 mg / mL.

[0050] 3. Control group Positive control group: Ketoconazole solution, a commonly used antifungal drug, was selected at a concentration of 1 μg / mL. Negative control group: Sterile saline solution was selected.

[0051] 4. Test methods Inoculate 100 μL of Malassezia culture onto modified Dixon medium and incubate at 32°C for 48–72 h. Once milky-white, round colonies with neat edges have formed on the plate, subculture once. Pick a single subcultured colony with a sterile inoculation loop, add it to 5 mL of sterile physiological saline, shake well, and adjust the bacterial suspension concentration to 0.5 McFarland turbidity using the McFarland turbidimetric method. This is the bacterial suspension used for the experiment.

[0052] Inside a laminar flow hood, take 0.1 mL of the prepared bacterial suspension and drop it into the center of a sterile modified Dixon medium. Use a sterile cotton swab to evenly spread the bacterial suspension across the entire surface of the medium. Place the medium in the laminar flow hood to air dry for 20 minutes. Using a sterile punch, evenly punch three wells on each culture medium plate that has been coated with bacterial solution (corresponding to the Forsythia suspensa extract solution group, positive control group, and negative control group, respectively). The wells should be spaced at least 25 mm apart, and the edge of the well should be at least 15 mm away from the edge of the plate to avoid interference. Use a sterile pipette to draw sterile physiological saline and gently rinse the culture medium core in the wells, then use a sterile pipette tip to aspirate the liquid from the wells. Add the corresponding sample to each of the three wells.

[0053] After adding the samples, the plates were placed in a 30℃ constant temperature incubator and incubated upside down for 48 hours. After the incubation period, the plates were removed and observed under natural light to see if a transparent inhibition zone appeared around each well. The diameter of the inhibition zone was measured with a ruler (accurate to 0.1 mm). Each inhibition zone was measured three times, and the average value was taken. The experimental results are recorded in Table 2.

[0054] Table 2 Results of antibacterial test

[0055] Table 2 shows that the diameter of the inhibition zone gradually increased with increasing extract concentration, indicating that the Forsythia suspensa extract has a concentration-dependent inhibitory effect on Malassezia. No inhibition zones were observed at low concentrations (0.125 mg / mL and 0.25 mg / mL), but they appeared starting from 0.5 mg / mL, and the diameter of the inhibition zone increased with increasing concentration. At the highest concentration of 16 mg / mL, the diameter of the inhibition zone was close to that of the positive control group, but slightly lower than that of ketoconazole solution.

[0056] Therefore, the Forsythia suspensa extract prepared by this invention can effectively inhibit Malassezia at appropriate concentrations, and has the potential for application in scalp care. It helps improve scalp folliculitis, seborrheic dermatitis, and dandruff caused by excessive proliferation of Malassezia. Simultaneously, it can be used as a scalp care ingredient to help maintain the scalp's microecological balance. Based on the above, this invention provides the application of the Forsythia suspensa extract in shampoo, wherein the amount of Forsythia suspensa extract added is 1% to 3% of the total mass of the shampoo.

[0057] This invention employs a modified emulsion treatment of Forsythia suspensa fruits in step S1, significantly improving the dissolution rate of forsythoside A and forsythoside A. It is the first time that an emulsion using a vitamin C-citric acid buffer as the aqueous phase and sunflower lecithin and a nonionic emulsifier as a composite emulsifier has been used for Forsythia suspensa fruit treatment, forming a novel extraction system. Both vitamin C and sunflower lecithin are natural components, aligning with green chemistry principles. This invention utilizes pretreatment at lower temperatures, effectively extracting components from Forsythia suspensa while minimizing the loss of active ingredients. Vitamin C not only acts as an antioxidant, protecting the active ingredients from oxidative damage, but its acidic environment also significantly improves the stability and dissolution rate of forsythoside A by inhibiting its hydrolysis or isomerization. This approach contrasts sharply with existing methods using organic solvents (such as ethanol) or ionic emulsifiers (such as sodium dodecyl sulfate). Vitamin C is acidic. Citric acid is used to adjust the pH of the system to 5.0-5.5, which not only allows for seamless connection with the subsequent enzymatic hydrolysis steps, but also moderately reduces the polarity of forsythoside and forsythoside A, making them easier to dissolve from the cell wall. At the same time, alkaline conditions are avoided, completely eliminating the risk of glycosidic bond cleavage or ester bond hydrolysis.

[0058] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A forsythia extract, characterized in that: The preparation method of the Forsythia extract includes the following steps: S1. Pretreatment: Forsythia fruit is placed in a modified emulsion and subjected to ultrasonic treatment at 35-45 kHz at 32-38℃. After soaking for 30-40 min, it is removed and vacuum dried at 50-54℃ and a vacuum degree of -0.08 to -0.09 MPa until the moisture content is ≤5%. The powder is then pulverized through a 60-100 mesh sieve to obtain Forsythia powder. The modified emulsion contains 0.3 wt%-0.5 wt% vitamin C, 0.2 wt%-0.4 wt% sunflower lecithin, and 0.015 wt%-0.050 wt% nonionic emulsifier. S2. Enzymatic hydrolysis: Add disodium hydrogen phosphate-citric acid buffer solution with a material-to-liquid ratio of 1:22-28 g / mL and a pH of 5.0-5.5 to the Forsythia powder, and add 1.2%-1.8% (by weight) of a complex enzyme to the Forsythia powder. Stir and hydrolyze at 44-48℃ and 180-240 rpm for 100-120 min, then inactivate the enzyme by incubation at 98-100℃ for 8-12 min, and cool to room temperature to obtain an enzymatic hydrolysis mixture. The complex enzyme consists of cellulase, pectinase, arabinosidase and β-glucosidase in a mass ratio of 2:1:0.5:1.

5. S3. Microwave extraction: Add an extraction solvent with a material-to-liquid ratio of 1:25-30 mL / g to the enzymatic hydrolysis mixture, and perform co-extraction at a microwave power of 350-450W, an ultrasonic frequency of 40-50 kHz, and a temperature of 58-65℃ for 20-30 min. Then centrifuge at 6000-7000 r / min for 15-20 min, and take the supernatant to obtain the crude extract. The extraction solvent is a mixture of a eutectic solvent and 70 vol% ethanol at a volume ratio of 1:3-4. S4. Centrifugal purification: Place the crude extract in a high-speed centrifuge and centrifuge at 8000-10000 r / min for 20-25 min. Pass the supernatant after centrifugation through a polyethersulfone ultrafiltration membrane with a molecular weight cutoff of 3-5 kDa and filter at an operating pressure of 0.12-0.15 MPa and a temperature of 30-35℃ to obtain the Forsythia extract.

2. The Forsythia extract according to claim 1, characterized in that: The forsythia fruit mentioned refers to the green forsythia fruit produced by 3- to 5-year-old forsythia plants, and the harvesting time is from late July to late August.

3. The Forsythia extract according to claim 1, characterized in that: The method for preparing the modified emulsion includes the following steps: adding vitamin C to deionized water and stirring until completely dissolved to obtain a VC solution; adjusting the pH of the VC solution to 5.0–5.5 with a 1 mol / L citric acid solution; adding sunflower lecithin and a nonionic emulsifier to the VC solution in sequence, and then ultrasonically emulsifying at 20–30 kHz for 12–18 min to obtain the modified emulsion.

4. A Forsythia extract according to claim 1 or 3, characterized in that: The nonionic emulsifier is composed of glyceryl monostearate and Tween 80 in a mass ratio of 1:

1.

5. The Forsythia extract according to claim 1, characterized in that: The cellulase activity is ≥5000 U / g, pectinase activity is ≥3000 U / g, arabinosidase activity is ≥3000 U / g, and β-glucosidase activity is ≥20000 U / g.

6. The Forsythia extract according to claim 1, characterized in that: The eutectic solvent is a choline chloride-propylene glycol eutectic solvent or a choline chloride-glycerol eutectic solvent, wherein the molar ratio of choline chloride to propylene glycol and the molar ratio of choline chloride to glycerol are both 1:

2.

7. The application of the Forsythia suspensa extract as described in any one of claims 1 to 6 in a shampoo, characterized in that: The amount of Forsythia suspensa extract added is 1% to 3% of the total mass of the shampoo.

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