Extraction process of buddleja officinalis maxim

Abstract

The present application relates to the extraction technical field of Flos Buddleja Officinalis, and discloses an extraction process of Flos Buddleja Officinalis, which comprises the following contents: raw material preparation: firstly, dry Flos Buddleja Officinalis medicinal material is crushed and passed through a 60-mesh sieve; preparation of ionic water: ionic liquid is prepared as an extraction liquid; mixed extraction: Flos Buddleja Officinalis powder is mixed with the extraction liquid according to a certain liquid-material ratio, and ultrasonic extraction is carried out under ice water bath; the ultrasonic extraction is used in the mixed extraction, the required power is 180-360 W, the required ultrasonic time is 5-25 min, the cation of the ionic liquid can be quaternary ammonium or imidazole, or quaternary ammonium, imidazole mixture, the microwave power is 700 W, the microwave time is 5-25 min, and the microwave temperature is 55-75 DEG C; the present application improves the extraction rate of five kinds of monomers of Flos Buddleja Officinalis by the method of microwave-ultrasonic and ionic liquid combined extraction, the method has the advantages of high extraction efficiency and low cost, and is suitable for large-scale production.

Description

Technical Field

[0001] This invention relates to the field of extraction technology of Buddleja officinalis, and more specifically to an extraction process for Buddleja officinalis. Background Technology

[0002] Buddleja officinalis extract is a traditional Chinese medicine extract primarily used to treat eye diseases. It has liver-nourishing and vision-improving effects, enhancing eyesight and relieving eye fatigue. The production process of Buddleja officinalis extract includes steps such as harvesting, washing, drying, pulverizing, extraction, filtration, concentration, and drying. Extraction and concentration are crucial steps, requiring the use of appropriate solvents and equipment to ensure the extract's effectiveness and purity. Buddleja officinalis extract has a wide range of applications, including in traditional Chinese medicine preparations and health products. It also possesses excellent antioxidant and anti-inflammatory properties, making it useful in treating various diseases such as hepatitis, nephritis, and gastritis.

[0003] Since Buddleja officinalis is a plant with medicinal value, containing a variety of beneficial components such as verbascoside, buddlejaside, luteolin, apigenin, and acaciain, traditional extraction methods suffer from low efficiency and high cost. Therefore, it is necessary to develop an efficient and low-cost extraction method for Buddleja officinalis. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, the present invention provides an extraction process for Buddleja officinalis to solve the problems existing in the background art.

[0005] This invention provides the following technical solution: an extraction process for Buddleja officinalis, comprising the following:

[0006] S1. Raw material preparation: First, pulverize the dried Buddleja officinalis herb and pass it through a 60-mesh sieve;

[0007] S2. Preparation of ionized water: Prepare ionized liquid as the extraction solution;

[0008] S3. Mixed extraction: Mix the pollen of Buddleja officinalis with the extract at a certain liquid-to-solid ratio, and perform ultrasonic extraction under an ice-water bath, followed by microwave extraction.

[0009] Furthermore, the mixed extraction is performed using ultrasonic extraction, requiring a power of 180-360W and an ultrasonic time of 5-25 minutes.

[0010] Furthermore, the cation of the ionic liquid can be a quaternary ammonium or imidazole, or a mixture of quaternary ammonium and imidazole.

[0011] Furthermore, the microwave power is 700W, the microwave time is 5-25min, and the microwave temperature is 55-75℃.

[0012] Furthermore, the ionic liquid has a polyhydric ratio of 10:1, 15:1, 20:1, 25:1, or 30:1. The technical effects and advantages of this invention are as follows:

[0013] 1. This invention improves the extraction rate of five monomers from Buddleja officinalis by using a combined microwave-ultrasound and ionic liquid extraction method. This method has the advantages of high extraction efficiency and low cost, and is suitable for large-scale production.

[0014] 2. This invention improves the extraction efficiency of Buddleja officinalis by adjusting parameters such as the molar concentration of ionic liquid, microwave time, and ultrasonic time. It has the advantages of being simple to implement and having significant effects, and is suitable for large-scale production of Buddleja officinalis. Attached Figure Description

[0015] Figure 1 The HPLC chromatograms of five reference standards of Buddleja officinalis are shown in this invention.

[0016] Figure 2 This is the HPLC chromatogram of the medicinal material *Buddleja officinalis* according to the present invention.

[0017] Figure 3 This is an HPLC chromatogram of the ethanol blank solvent used in the experiments of this invention.

[0018] Figure 4 This is the HPLC chromatogram of Paeonia lactiflora according to the present invention.

[0019] Figure 5 This is the HPLC chromatogram of the mixed standard of Paeonia lactiflora and Buddleja officinalis of the present invention.

[0020] Figure 6 This is a schematic diagram illustrating the extraction of material components according to the present invention.

[0021] Figure 7 This is a schematic diagram illustrating the effect of the nine ionic liquids of the present invention on the extraction rates of five monomers from Buddleja officinalis.

[0022] Figure 8 This is a schematic diagram illustrating the extraction rates of buddleja glycosides by the nine ionic liquids of this invention.

[0023] Figure 9 This is a schematic diagram illustrating the effect of the molar concentration of tetraethylammonium bromide on extraction according to the present invention.

[0024] Figure 10 This is a schematic diagram illustrating the effect of ultrasonic power on the extraction rate in the first aspect of this invention.

[0025] Figure 11 This is a schematic diagram illustrating the effect of the second ultrasonic power on the extraction rate according to the present invention.

[0026] Figure 12 This is a schematic diagram illustrating the effect of ultrasonic time on extraction according to the present invention.

[0027] Figure 13 This is a schematic diagram illustrating the effect of microwave time on extraction according to the present invention.

[0028] Figure 14 This is a schematic diagram illustrating the effect of microwave temperature on extraction in the first step of this invention.

[0029] Figure 15 This is a schematic diagram illustrating the effect of the second microwave temperature on the extraction process according to the present invention.

[0030] Figure 16 This is a schematic diagram illustrating the effect of the material-liquid ratio on extraction according to the present invention.

[0031] Figure 17 This is a schematic diagram of the response surface of the effect of ultrasonic time on the total extraction rate of five monomers from Buddleja officinalis according to the present invention.

[0032] Figure 18 This is a schematic diagram of the response surface contour lines showing the effect of ultrasonic time on the total extraction rate of five monomers from Buddleja officinalis according to the present invention.

[0033] Figure 19 This is a schematic diagram of the response surface of the effect of microwave time on the total extraction rate of five monomers of Buddleja officinalis according to the present invention.

[0034] Figure 20 This is a schematic diagram of the response surface contour lines showing the effect of microwave time on the total extraction rate of five monomers from Buddleja officinalis according to the present invention.

[0035] Figure 21 This is a schematic diagram of the response surface of the effect of the molar concentration of the ionic liquid on the total extraction rate of five monomers of Buddleja officinalis.

[0036] Figure 22 This is a schematic diagram of the response surface contour lines showing the effect of the molar concentration of the ionic liquid on the total extraction rate of five monomers from Buddleja officinalis.

[0037] Figure 23 This is a schematic diagram of the response surface of the effect of ultrasonic time on the extraction rate of buddleja officinalis glycosides in this invention.

[0038] Figure 24 This is a schematic diagram of the response surface contour lines showing the effect of ultrasound time on the extraction rate of buddleja officinalis glycosides in this invention.

[0039] Figure 25 This is a schematic diagram of the response surface of the effect of microwave time on the extraction rate of buddleja officinalis glycosides in this invention.

[0040] Figure 26 This is a schematic diagram of the response surface contour lines showing the effect of microwave time on the extraction rate of buddleja officinalis glycosides in this invention.

[0041] Figure 27This is a schematic diagram of the response surface contour lines illustrating the effect of the molar concentration of the ionic liquid on the extraction rate of buddleja officinalis glycosides in this invention. Detailed Implementation

[0042] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The extraction process of Buddleja officinalis involved in the present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] This invention provides an extraction process for Buddleja officinalis, comprising the following:

[0044] S1. Raw material preparation: First, pulverize the dried Buddleja officinalis herb and pass it through a 60-mesh sieve;

[0045] S2. Preparation of ionized water: Prepare ionized liquid as the extraction solution;

[0046] S3. Mixed extraction: Mix the pollen of Buddleja officinalis with the extract at a certain liquid-to-solid ratio, and perform ultrasonic extraction under an ice-water bath, followed by microwave extraction.

[0047] The mixed extraction process employs ultrasonic extraction, requiring a power of 180-360W and an ultrasonic time of 5-25 minutes.

[0048] The cation of the ionic liquid can be a quaternary ammonium or imidazole, or a mixture of quaternary ammonium and imidazole.

[0049] The microwave power is 700W, the microwave time is 5-25min, and the microwave temperature is 55-75℃.

[0050] The ionic liquid has a ratio of 10:1, 15:1, 20:1, 25:1, or 30:1.

[0051] Accurately weigh appropriate amounts of the reference standards verbascoside, scutellarin, luteolin, apigenin, and farnesin, dissolve them in methanol and dilute to volume to prepare reference stock solutions with mass concentrations of: verbascoside 1.0000 mg·ml⁻¹, scutellarin 50.0 μg·ml⁻¹, luteolin 1.0000 mg·ml⁻¹, apigenin 1.0000 mg·ml⁻¹, and farnesin 1.0000 mg·ml⁻¹, respectively.

[0052] Accurately measure appropriate amounts of each reference stock solution, dilute to volume with methanol, and prepare a mixed solution containing 0.05 mg·ml⁻¹ of verbascoside, buddleja glycoside, luteolin, apigenin, and acacia glycoside. Accurately weigh 20.00 mg of crude extract of Buddleja officinalis extracted with 95% ethanol, dissolve in methanol, dilute to 10 mL, sonicate for 30 min to dissolve the crude extract, and centrifuge at 4000 rpm for 10 min to obtain the sample test solution. Filter the solution through a 0.22 μm microporous membrane before injection.

[0053] Take the mixed reference solution of Buddleja officinalis and dilute it to appropriate concentrations: 0.05 mg·ml⁻¹, 0.04 mg·ml⁻¹, 0.03 mg·ml⁻¹, 0.02 mg·ml⁻¹, 0.01 mg·ml⁻¹, and 0.005 mg·ml⁻¹. Inject the sample according to the chromatographic conditions in section “2.2.1”, record the peak areas of the five components of Buddleja officinalis, and perform linear regression on the peak area (Y) against the mass concentration (X, μg / mL). Plot the regression equation using the least squares method and prepare the standard curves for the five standards. According to the R² of the curve equation, the R² is between 0.9991 and 1, indicating a good linear relationship.

[0054] Take a mixed reference solution of Buddleja officinalis with a concentration of 0.03 mg·ml⁻¹, and inject it into the following chromatographic conditions: Waters Symmetry C18 Columns (4.6 mm × 250 mm, 5 μm); column temperature: 25 ℃; mobile phase: methanol (A) - 0.1% phosphoric acid water (B), gradient elution (0→5 min, 5% A → 40%; 5→15 min, 40% A → 50%; 15→20 min, 50% A → 63% A; 20→35 min, 63% A → 100% A); flow rate: 0.8 ml·min⁻¹; detection wavelength: 338 nm; injection volume: 10 μl. Inject five times consecutively, record the peak areas of verbascoside, buddlejaside, luteolin, apigenin, and farnesin, and calculate the RSD values ​​of the peak areas of the five reference standards.

[0055] Weigh 6 portions of Buddleja officinalis powder, inject them into the sample test solution under the specified chromatographic conditions, record the peak areas of verbascoside, buddlejaside, luteolin, apigenin and acaciain, and calculate the content and RSD value of the Buddleja officinalis sample.

[0056] Accurately measure the mixed reference solution of Buddleja officinalis to a concentration of 0.04 mg·ml⁻¹. After preparation, perform chromatographic analysis under the specified chromatographic conditions at 0, 3, 6, 9, 12, 18, and 24 h. Record the peak areas of verbascoside, buddlejaside, luteolin, apigenin, and acaciaside, and calculate the RSD values ​​of the peak areas of the five reference standards.

[0057] Take the blank solvent ethanol used in the experiment, and record the retention times of verbascoside, buddleja glycoside, luteolin, apigenin and acacia glycoside under the specified chromatographic conditions. Observe whether their retention times overlap with the retention times of the five components of Buddleja officinalis.

[0058] Take a sample solution of *Buddleja officinalis* with a known content, and add 0.5, 1, and 1.5 times the volume of the mixed reference standard of *Buddleja officinalis*, respectively. Under the specified chromatographic conditions, record the peak areas of verbascoside, buddlejaside, luteolin, apigenin, and farnesin, and calculate the recovery rate and RSD value of the five reference standards.

[0059] Reference substance Retention time Theoretical plate number Separation degree Tailing factor T Verbascoside 13.371 17336.41 1.925056 1.087902 Bajoside 24.591 77276.03 1.311972 1.166686 Luteolin 25.559 89929.63 2.79502 1.256961 Apigenin 27.672 111316.5 6.298503 1.250169 Acacetin 32.044 170336 1.399554 1.227357

[0060] Simultaneously combined Figures 1-2 The chromatographic peaks of the medicinal materials and reference standards are sharp, with no tailing of the main peak; the theoretical plate number is greater than the traditional 1000; therefore, each monomer can be effectively separated under these chromatographic conditions.

[0061] Using the external standard method, a standard curve was plotted and analyzed with the mass concentration (X) of chemical components in Buddleja officinalis as the abscissa and the peak area (Y) as the ordinate, as shown in the table below:

[0062] Reference substance Regression equation Linear range (mg / ml) Correlation coefficient (r) Verbascoside [Y1 = 20000000 x + 19223] 0.005～0.05 [r1 = 0.9991] Bajoside [Y2 = 20000000x - 6794.8] 0.005～0.05 [r2 = 0.9999] Luteolin [Y3 = 50000000x - 34436] 0.005～0.05 [r3 = 0.9993] Apigenin [Y4 = 60000000x - 26031] 0.005～0.05 [r4 = 0.9997] Acacetin [Y5 = 50000000 x - 17989] 0.005～0.05 [r5 = 0.9998]

[0063] The results showed that buddleja glycoside, buddleja glycoside, luteolin, apigenin and farnesin had good linear relationships in the range of 0.005-0.05 mg / ml, and the correlation coefficients r were all greater than 0.9991.

[0064] The peak area results of five consecutive injections of the mixed reference standard of Buddleja officinalis are shown in the HPLC instrument precision results table of chemical components of Buddleja officinalis:

[0065]

[0066] The results showed that the RSDs of the peak areas of buddleja glycoside, buddleja glycoside, luteolin, apigenin and acacia glycoside were 0.850813145%, 0.585701746%, 0.287369822%, 0.395693106%, and 0.264265166%, respectively, which were less than the 2% limit specified in the pharmacopoeia, indicating that the instrument had good precision.

[0067]

[0068] The value was still less than 2% after a second measurement, indicating that the instrument has good precision.

[0069] To prevent random bias, multiple measurements were performed, and the results are shown in the table below:

[0070]

[0071]

[0072] The result of the subsequent measurement was still less than 2%, indicating that the instrument has good precision.

[0073] When performing measurements, detection limits and quantitation limits are set, as shown in the table:

[0074] Reference substance Limit of detection (pg / ml) Limit of quantification (pg / ml) Verbascoside 0.3 1 Bajoside 0.03 0.1 Luteolin 0.03 0.1 Apigenin 0.03 0.1 Acacetin 0.03 0.1

[0075] Reference Figures 3-5 The retention time of the ethanol solvent used in the experiment can be seen from the figure. The retention time of the blank solvent ethanol used in the experiment did not interfere with the chromatographic peaks of each monomer of Buddleja officinalis, indicating that the method has good specificity.

[0076] Furthermore, the recovery rate should be tested under proper storage conditions; the recovery rate results are shown in the table below:

[0077]

[0078]

[0079]

[0080] This gives the result of the HPLC recovery rate of Buddleja officinalis.

[0081] The specific process for extracting the five monomers from Buddleja officinalis is as follows:

[0082] The dried Buddleja officinalis herb was pulverized, passed through a 60-mesh sieve, and stored in a dark place. 10.0g of Buddleja officinalis pollen was accurately weighed and added to a 60% ethanol and ionic liquid mixed aqueous solution at the liquid-to-solid ratio. The solution was placed in an ultrasonic cell disruptor, and ultrasonic extraction was performed under an ice-water bath. After ultrasonic extraction, the solution was stirred evenly and placed in a microwave extractor. Microwave extraction parameters were set. After microwave extraction, the extract was shaken evenly, allowed to stand and precipitate, and the supernatant was collected for later use. After the sample solution was prepared, the contents of five monomers were determined by HPLC, and the extraction rate was calculated. Based on single-factor experiments, the extraction process of five monomers was optimized. Seven important factors affecting the extraction rate of flavonoids from *Buddleja officinalis* were selected for single-factor experiments: ionic liquid type, ionic liquid molar concentration, solid-liquid ratio, ultrasonic time, ultrasonic power, microwave time, and microwave temperature. The influence of these factors on the extraction rate of the five monomers from *Buddleja officinalis* was investigated. The optimal condition range could be determined based on the single-factor experiments. Since the extraction was applied to total flavonoids from *Buddleja officinalis*, cationic quaternary ammonium and imidazole ionic liquids were used because they can form a strong interaction with total flavonoids from *Buddleja officinalis*. Under practical conditions, the pre-selected ionic liquid types included:

[0083]

[0084] Different types of ionic liquids were added to 60% ethanol at a concentration of 0.035 mol / L to prepare extracts of flavonoids from *Buddleja officinalis* containing ionic liquids. Extraction was performed using a liquid-to-solid ratio of 20:1 mL / g, with a microwave power of 700 W, an ultrasonic power of 270 W, an ultrasonic time of 3.0 min, a microwave time of 5.0 min, and a microwave temperature of 60℃. A combined microwave-ultrasound and ionic liquid extraction method was employed. The contents of the five monomers were measured and recorded, with 60% ethanol and no added ionic liquid serving as a control. The effects of nine ionic liquids on the extraction rates of five monomers from *Buddleja officinalis* were investigated.

[0085] The experimental parameters were as follows: liquid-to-solid ratio 20:1 mL / g, microwave power 700 W, ultrasonic power 270 W, ultrasonic time 4.0 min, microwave time 5.0 min, microwave temperature 60℃. Tetraethylammonium bromide was added to a 60% ethanol aqueous solution at concentrations of 0.015, 0.025, 0.035, 0.045, and 0.055 mol / L to prepare extracts of total flavonoids from *Buddleja officinalis* at different molar concentrations. Total flavonoids from *Buddleja officinalis* were extracted using a combined microwave-ultrasound and ionic liquid extraction method. The contents of five monomers in *Buddleja officinalis* were detected to investigate the effect of the molar concentration of the ionic liquid on the extraction rate of the five monomers. The results are as follows: Figure 8 From the information, we can see that 0.035 mol / L is the optimal molar concentration;

[0086] Confirmation by ultrasound:

[0087] The experimental parameters were as follows: liquid-to-solid ratio 20:1 mL / g, tetraethylammonium bromide molar concentration 0.0411 mol / L, microwave power 700 W, ultrasonic time 4.0 min, microwave time 5.0 min, microwave temperature 60℃, and ultrasonic power 180, 234, 270, 324, and 360 W, respectively. Total flavonoids from *Buddleja officinalis* were extracted using a microwave-ultrasound-ionic liquid combined extraction method. The contents of five monomers in *Buddleja officinalis* were also detected to investigate the effect of ultrasonic power on the extraction rate of the five monomers from *Buddleja officinalis*.

[0088] The experimental parameters were as follows: liquid-to-solid ratio 20:1 mL / g, tetraethylammonium bromide molar concentration 0.0411 mol / L, microwave power 700 W, microwave time 5.0 min, microwave temperature 60 ℃, ultrasonic power 270 W, and ultrasonic times of 5.0, 10.0, 15.0, 20.0, and 25.0 min. Total flavonoids from *Buddleja officinalis* were extracted using a microwave-ultrasound-ionic liquid combined extraction method. The contents of five monomers in *Buddleja officinalis* were then determined to investigate the effect of ultrasonic time on the extraction rate of the five monomers from *Buddleja officinalis*.

[0089] Microwave confirmation:

[0090] The experimental parameters were as follows: liquid-to-solid ratio 15:1 mL / g, tetraethylammonium bromide molar concentration 0.0411 mol / L, microwave power 700 W, microwave temperature 75 ℃, ultrasonic power 270 W, ultrasonic time 15.0 min, and microwave times of 5.0, 10.0, 15.0, 20.0, and 25.0 min. Total flavonoids from *Buddleja officinalis* were extracted using a microwave-ultrasound-ionic liquid combined extraction method. The contents of five monomers in *Buddleja officinalis* were also detected to investigate the effect of microwave time on the extraction rate of the five monomers from *Buddleja officinalis*.

[0091] The experimental parameters were as follows: liquid-to-solid ratio 20:1 mL / g, tetraethylammonium bromide molar concentration 0.0411 mol / L, microwave power 700 W, ultrasonic power 270 W, ultrasonic time 15.0 min, microwave time 8 min, and microwave temperatures 55, 60, 65, 70, and 75 °C. Total flavonoids from *Buddleja officinalis* were extracted using a microwave-ultrasound-ionic liquid combined extraction method. The contents of five monomers in *Buddleja officinalis* were then determined to investigate the effect of microwave temperature on the extraction rate of the five monomers from *Buddleja officinalis*.

[0092] Determining the liquid-to-solid ratio:

[0093] The experimental parameters were as follows: tetraethylammonium bromide molar concentration 0.0411 mol / L, microwave power 700 W, ultrasonic power 270 W, ultrasonic time 5.0 min, microwave time 12.0 min, microwave temperature 60℃, and liquid-to-solid ratios of 10:1, 15:1, 20:1, 25:1, and 30:1 mL / g. Total flavonoids from *Buddleja officinalis* were extracted using a combined microwave-ultrasound and ionic liquid extraction method. The contents of five monomers in *Buddleja officinalis* were also determined to investigate the effect of the liquid-to-solid ratio on the extraction rate of the five monomers from *Buddleja officinalis*.

[0094] Experimental Design:

[0095] A three-level, three-factor response surface methodology was employed, using ionic liquid molar concentration, microwave time, and ultrasonic time as variables, with each variable having three levels. The extraction rate of the main monomer of *Buddleja officinalis* was used as a measure of the extraction process, thereby obtaining the optimal extraction conditions for *Buddleja officinalis*. The response surface methodology table is designed as follows: (Table of response surface analysis factors and levels follows).

[0096]

[0097]

[0098] Reference Figure 6 The data results obtained using the traditional heating reflux extraction method are as follows:

[0099]

[0100] Screening of ionic liquid types:

[0101] Different types of ionic liquids were added to 60% ethanol at a concentration of 0.035 mol / L to prepare extracts of flavonoids from *Buddleja officinalis* containing ionic liquids. Extraction was performed using a liquid-to-solid ratio of 20:1 mL / g, with a microwave power of 700 W, an ultrasonic power of 270 W, an ultrasonic time of 3.0 min, a microwave time of 5.0 min, and a microwave temperature of 60℃. A combined microwave-ultrasound and ionic liquid extraction method was employed. The contents of five monomers were detected, and the extraction rate was calculated. The experimental results are as follows: Figures 7-8 The extraction rate of 60% ethanol extraction (without adding any ionic liquid) was used as a control. The effects of 9 ionic liquids on the extraction rates of 5 monomers of Buddleja officinalis are shown in the table below:

[0102]

[0103]

[0104] Depend on Figures 7-8As shown in the table above, the ionic liquid tetraethylammonium bromide is inexpensive and has good stability. It is possible that quaternary ammonium ionic liquids easily form hydrogen bonds with buddleoside and verbascoside in Buddleja officinalis, and there is an interaction force. The ethanol aqueous solution of tetraethylammonium bromide can increase the solubility of the five monomers, increase the porosity of Buddleja officinalis pollen, and improve the extraction efficiency. Therefore, adding the ionic liquid tetraethylammonium bromide to the original ethanol extraction process of Buddleja officinalis can greatly improve the extraction efficiency of the five monomers of Buddleja officinalis.

[0105] Five monomers from *Buddleja officinalis* were extracted using a combined microwave-ultrasound and ionic liquid extraction method. Based on the results of single-factor experiments, the optimal parameters were determined: ultrasonic power 252 W, ethanol volume fraction 60%, solid-liquid ratio 1:20, microwave temperature 75℃, microwave power 700 W, and tetraethylammonium bromide as the ionic liquid. The ionic liquid molar concentration, microwave time, and ultrasonic time were considered as three influencing factors in the extraction process, with the extraction rate of buddleja glycosides and the total extraction rate of the five monomers as the response values. RSM optimization experiments were conducted to optimize these factors using the Box-Behnken principle and Design-Expert 12.0. The experimental design and results are shown in the following table:

[0106]

[0107]

[0108] The total extraction rate of the five monomers from Buddleja officinalis is used as a measure of the extraction process.

[0109] To test the effectiveness of the regression equation and the influence of each factor on the extraction process of Buddleja officinalis, an analysis of variance was performed on the regression equation of the data obtained in this experiment. The results are shown in the analysis of variance table of the regression model:

[0110]

[0111]

[0112] Regression analysis was performed on the data using software to establish a regression model between the molar concentration of the ionic liquid, microwave time, and ultrasonic time. The regression equation is: Y 总 =30.0635+0.0874A+0.6931B+0.2012C+0.0982AB-0.4096AC+0.1121BC-0.3788A 2 -0.8879B 2 -0.3055C 2

[0113] The reliability of this regression model can be determined by the results analysis and correlation coefficients, as shown in the table above. The p-value can be used to detect the significance of the coefficients; a smaller p-value indicates a greater influence of the corresponding dependent variable. Simultaneously, the p-value can also test the interaction of combined factors. When the p-value < 0.01, it indicates that the criterion is highly significant. Using the variance analysis of the quadratic model, the results show that the quadratic multinomial lack-of-fit term in the established model for the extraction process of *Buddleja officinalis* is not significant, and the model is highly significant (P < 0.01). The coefficient of determination R² of this regression model is 0.9833, and the adjusted coefficient of determination R²Adj is 0.9617. The low CV% value indicates that the model has good repeatability and reliability. Therefore, the model has a good fit and can be used for the analysis and prediction of the combined microwave-ultrasound and ionic liquid extraction process for five monomers of *Buddleja officinalis*. The first-order terms B and C are highly significant, while A is not significant; the interaction terms AC are highly significant, while AB and BC are not significant; the second-order terms A², C², and B² are all highly significant. The F-value shows the primary and secondary factors affecting the extraction process of Buddleja officinalis: B microwave time > C ultrasonic time > A ionic liquid molar concentration.

[0114] To test the effectiveness of the regression equation and the influence of each factor on the extraction process of Buddleja officinalis, an analysis of variance was performed on the regression equation of the data obtained in this experiment. The results are shown in the following table:

[0115]

[0116]

[0117] Regression analysis was performed on the data in the Box-Benhnken experimental design and results table using Design-Expert 12.0 software. A regression model was established between the molar concentration of the ionic liquid, microwave time, and ultrasonic time. The regression equation is as follows:

[0118] Y 蒙花苷 =11.80+0.0995A+0.2949B+0.1049C-0.1331AB-0.1011AC-0.0855BC-0.0684A 2 -0.1225B 2 -0.1160C 2The reliability of this regression model can be determined by results analysis and correlation coefficients, as shown in the variance verification analysis table of the regression model. The p-value can be used to detect the significance of the coefficients; a smaller p-value indicates a greater influence of the corresponding dependent variable. Simultaneously, the p-value can also test the interaction of combined factors. When the p-value < 0.05, the determination index is considered significant. Using the variance analysis of the quadratic model, the results show that the quadratic multinomial lack-of-fit term in the established model for the extraction process of *Buddleja officinalis* is not significant, and the model is significant (P < 0.05). The coefficient of determination R² of this regression model is 0.8901, and the adjusted coefficient of determination R²Adj is 0.7489. The low CV% value indicates that the model has good repeatability and reliability. Therefore, the model has a good fit and can be used for the analysis and prediction of the combined microwave-ultrasound and ionic liquid extraction process of buddleja officinalis glycosides. The first-order term B is highly significant, while A and C are not significant; the interaction terms AC, AB, and BC are all not significant; the quadratic terms A², C², and B² are all not significant. The F-values ​​indicate the primary and secondary factors affecting the extraction process of *Buddleja officinalis*: B. Microwave time > C. Ultrasonic time > A. Ionic liquid molar concentration.

[0119] Reference Figures 16-27 Design-Expert software was used to obtain corresponding response surface plots and contour plots to analyze the interactive effects of these factors on the extraction process of *Buddleja officinalis*. In the response surface plot, a steeper slope indicates a greater impact on the extraction process, and also a more significant impact on the total extraction rate of the five monomers of *Buddleja officinalis*. The contour plot provides a more intuitive view of the influence of each factor on the extraction rate, thus helping to better identify the optimal process parameters. The center of the smallest ellipse in the contour lines represents the highest point of the response surface, and the shape of the contour lines reflects the strength of the interactive effects; an ellipse indicates a significant effect, while a circle indicates an insignificant effect.

[0120] A gentle slope on the response surface indicates that the interaction between the two factors is insignificant; conversely, a steep slope indicates a significant interaction. The density and shape of contour lines also reflect the strength of the interaction; denser contour lines indicate a more significant effect, while sparser contour lines indicate the opposite. An ellipse indicates a significant interaction between the two factors, while a circle indicates an insignificant interaction. Figure 8 It can be seen that the interaction between the molar concentration of the ionic liquid and the ultrasonic time on the extraction process is parabolic, and the contour plot shows a very obvious oblique elliptical shape. This indicates that the interaction between the molar concentration of the ionic liquid and the ultrasonic time has a highly significant impact on the total extraction rate of the five monomers of *Buddleja officinalis*. Furthermore, the 3D response surface plot shows that the response surface slopes for microwave time with ionic liquid molar concentration, ultrasonic time, and ultrasonic time with ionic liquid molar concentration are relatively steep. The contour line density of ultrasonic time and microwave time is higher than that of ionic liquid molar concentration, indicating that ultrasonic time and microwave time have a more significant impact on the total extraction rate of the five monomers of *Buddleja officinalis* than ionic liquid molar concentration, and their influence on the extraction process is extremely significant.

[0121] Based on the above analysis, the optimal combination obtained by Design-Expert simulation is an ionic liquid molar concentration of 0.035 mol / L, ultrasonic time of 20 min, and microwave time of 20 min. To verify the accuracy of the model, three parallel simulations were performed under these conditions, and the results were close to the predicted values ​​(P < 0.05). The results indicate that response surface methodology optimization of the microwave-ultrasonic combined extraction process with ionic liquid for *Buddleja officinalis* is feasible and represents the optimal option.

[0122] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0123] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0124] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for the extraction of Buddleja officinalis, characterized in that, The application relates to a method for extracting a medicinal material of Flos Genkwa. S1, raw material preparation: first, dry Flos Genkwa medicinal material is crushed and passed through a 60-mesh sieve; S2, preparation of ionic water: ionic liquid is prepared as an extraction liquid; S3, mixed extraction: Flos Genkwa powder and the extraction liquid are mixed according to a certain liquid-material ratio, and ultrasonic extraction is carried out under an ice water bath, and then microwave extraction is used; The ionic liquid is tetraethylammonium chloride.

2. The extraction process of Buddleja officinalis according to claim 1, characterized in that: When the mixed extraction is carried out, ultrasonic extraction is adopted, the required power is 180-360 W, and the required ultrasonic time is 5-25 min.

3. The extraction process of Buddleja officinalis according to claim 1, characterized in that: The microwave power is 700 W, the microwave time is 5-25 min, and the microwave temperature is 55-75 DEG C.

4. The extraction process of Buddleja officinalis according to claim 1, characterized in that: The liquid-material ratio of the ionic liquid is 10:1, 15:1, 20:1, 25:1 or 30:1.

Images