阅读说明：本技术 一种用于同时提高前胡提取物祛痰和平喘作用的制备方法 (A method for simultaneously improving expectorant and antiasthmatic effects of radix Peucedani extract ) 是由 刘景萍 刘全国 陈克领 于 2021-07-16 设计创作，主要内容包括：本发明提供一种用于同时提高前胡提取物祛痰和平喘作用的制备方法,包括以下步骤：取前胡中药材破碎,磨粉,过筛,得前胡粉,置于乙醇溶液中发酵,得到发酵混合物；将发酵混合物置于微波提取,过滤,得到微波提取液和滤渣,将微波提取液浓缩,得微波提取浓缩液；将滤渣置于乙醇溶液加热提取滤过,滤液合并,减压回收乙醇,浓缩,得回流提取浓缩液；将上述浓缩液混合,加入到大孔树脂中,采用乙醇溶液梯度洗脱；将最后收集的洗脱液减压浓缩,减压干燥,得到目标前胡提取物。采用本发明制备方法得到前胡提取物,提高白花前胡甲素、乙素和香豆素转移率,明显提高前胡提取物祛痰和平喘作用。(The invention provides a preparation method for simultaneously improving expectorant and antiasthmatic effects of radix peucedani extract, which comprises the following steps: crushing radix Peucedani, grinding into powder, sieving to obtain radix Peucedani powder, and fermenting in ethanol solution to obtain fermented mixture; placing the fermented mixture in microwave extraction, filtering to obtain microwave extract and filter residue, and concentrating the microwave extract to obtain microwave extract concentrated solution; extracting the residue with ethanol under heating, filtering, mixing filtrates, recovering ethanol under reduced pressure, and concentrating to obtain concentrated solution; mixing the above concentrated solutions, adding into macroporous resin, and gradient eluting with ethanol solution; and concentrating the finally collected eluent under reduced pressure, and drying under reduced pressure to obtain the target peucedanum praeruptorum extract. The peucedanum praeruptorum dunn extract obtained by the preparation method of the invention improves the transfer rate of praeruptorin A, B and coumarin, and obviously improves the effects of eliminating phlegm and relieving asthma of the peucedanum praeruptorum dunn extract.)

1. A preparation method for simultaneously improving phlegm eliminating and asthma relieving effects of a radix peucedani extract is characterized by comprising the following steps:

(1) pretreatment: crushing radix Peucedani, grinding into powder, sieving to obtain radix Peucedani powder, placing in 60-70% ethanol solution, and fermenting at 35-40 deg.C for 80-100min to obtain fermented mixture;

(2) primary extraction: placing the fermentation mixture obtained in the step (1) in microwave extraction, filtering to obtain microwave extracting solution and filter residue, and concentrating the microwave extracting solution to obtain microwave extracting concentrated solution;

(3) secondary extraction: placing the filter residue in the step (2) into 60-70% ethanol solution, heating and extracting for 2-3 times, refluxing for 0.8-1.2h each time, filtering, mixing filtrates, recovering ethanol under reduced pressure, and concentrating to obtain reflux extract concentrate;

(4) gradient elution: mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, eluting by using 40-50 wt% ethanol solution, then eluting by using 80-90 wt% ethanol solution, and finally collecting 60-70 wt% ethanol solution eluent;

(5) and concentrating the finally collected eluent under reduced pressure, and drying under reduced pressure to obtain the target peucedanum praeruptorum extract.

2. The preparation method according to claim 1, wherein, in the step (2), the microwave extraction process: the extraction is performed for 40-50min under the power of 300-400W, and then for 20-30min under the power of 550-650W.

3. The production method according to claim 1 or 2, wherein in the step (1), the mass-to-volume ratio kg/L of the decursin powder to the ethanol solution is 1: 2-3.

4. The preparation method according to claim 2, wherein in the step (2), the solid content of the microwave extraction concentrated solution is 50-60%.

5. The method according to claim 1, wherein in step (3), the ethanol solution is used in an amount of 4 to 6 times the weight of the residue per heating extraction.

6. The preparation method according to claim 5, wherein in the step (3), the heating extraction is performed for 3 times, the 1 st time ethanol solution is used for 6 times of the weight of the filter residue, the 2 nd time ethanol solution is used for 5 times of the weight of the filter residue, and the 3 rd time ethanol solution is used for 4 times of the weight of the filter residue.

7. The preparation method according to claim 1, wherein in the step (3), the solid content of the reflux extraction concentrate is 50-60%.

8. The method according to claim 1, wherein in the step (4), the flow rate of the eluent for the gradient elution is 8-10 mL/min.

9. The method according to claim 1, wherein in the step (4), the amount of the macroporous resin is 0.8 to 1.2 times the weight of the comfrey powder.

10. The production method according to any one of claims 1 to 9, wherein, in the step (5), the fluid extract is concentrated under reduced pressure to a relative density of 1.25 to 1.30 at a concentration temperature of 60 ℃.

Technical Field

The invention relates to the field of natural medicines, in particular to a preparation method for simultaneously improving phlegm eliminating and asthma relieving effects of a radix peucedani extract.

Background

Radix Peucedani is dried root of Peucedanum praeruptorum Dunn of Umbelliferae, has effects of dispelling pathogenic wind heat, lowering qi, and eliminating phlegm, and mainly contains volatile oil, multiple coumarins such as Peucedanum praeruptorum, and contains trace amount of decursin. The water and alcohol extract of radix peucedani can increase the respiratory tract secretion of mice, relieve the spasm of guinea pig bronchial smooth muscle and rabbit small intestine smooth muscle caused by various medicaments, obviously increase the output of phenol red of the respiratory tract of mice, has the effect of eliminating phlegm and has the effect of relieving asthma of histamine asthma. The existing method can not fully extract the effective components, which is not beneficial to fully exerting the efficacy of the peucedanum root extract.

Disclosure of Invention

In view of the above, the invention provides a preparation method for simultaneously improving the phlegm eliminating and asthma relieving effects of the radix peucedani extract, which obviously improves the extraction of effective components, especially improves the transfer rates of praeruptorin A, B and coumarin, and obviously improves the phlegm eliminating and asthma relieving effects of the radix peucedani extract.

The technical scheme of the invention is realized as follows: a preparation method for simultaneously improving expectorant and antiasthmatic effects of radix Peucedani extract comprises the following steps:

(1) pretreatment: crushing radix Peucedani, grinding into powder, sieving to obtain radix Peucedani powder, placing in 60-70% ethanol solution, and fermenting at 35-40 deg.C for 80-100min to obtain fermented mixture;

(2) primary extraction: placing the fermentation mixture obtained in the step (1) in microwave extraction, filtering to obtain microwave extracting solution and filter residue, and concentrating the microwave extracting solution to obtain microwave extracting concentrated solution;

(3) secondary extraction: placing the filter residue in the step (2) into 60-70% ethanol solution, heating and extracting for 2-3 times, refluxing for 0.8-1.2h each time, filtering, mixing filtrates, recovering ethanol under reduced pressure, and concentrating to obtain reflux extract concentrate;

(4) gradient elution: mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, eluting by using 40-50 wt% ethanol solution, then eluting by using 80-90 wt% ethanol solution, and finally collecting 60-70 wt% ethanol solution eluent;

(5) and concentrating the finally collected eluent under reduced pressure, and drying under reduced pressure to obtain the target peucedanum praeruptorum extract.

Preferably, step (2), the microwave extraction process: the extraction is performed for 40-50min under the power condition of 300-400W, and then for 20-30min under the power condition of 550-650W.

Preferably, in the step (1), the mass-to-volume ratio kg/L of the decursine root powder and the ethanol solution is 1: 2-3.

Preferably, in the step (2), the solid content of the microwave extraction concentrated solution is 50-60%.

Preferably, in step (3), the amount of the ethanol solution used in each heating extraction is 4-6 times of the weight of the filter residue. More preferably, the heating extraction is performed for 3 times, the usage amount of the 1 st ethanol solution is 6 times of the weight of the filter residue, the usage amount of the 2 nd ethanol solution is 5 times of the weight of the filter residue, and the usage amount of the 3 rd ethanol solution is 4 times of the weight of the filter residue.

Preferably, in the step (3), the solid content of the reflux extraction concentrated solution is 50-60%.

Preferably, in step (4), the flow rate of the eluent for the gradient elution is 8-10 mL/min.

Preferably, in the step (4), the dosage of the macroporous resin is 0.8-1.2 times of the weight of the decursite powder.

Preferably, in the step (5), the pressure reduction concentration is carried out to obtain clear paste with the relative density of 1.25-1.30, and the concentration temperature is 60 ℃.

Compared with the prior art, the invention has the beneficial effects that:

the preparation method adopts certain conditions for pre-fermentation, a specific program for microwave extraction and combined reflux extraction, and finally a certain program for gradient elution to obtain the peucedanum praeruptorum dunn extract, so that the extraction of effective components is obviously improved, the transfer rates of praeruptorin A, B and coumarin are especially improved, and the phlegm eliminating and asthma relieving effects of the peucedanum praeruptorum dunn extract are obviously improved.

The invention adopts specific conditions for pre-fermentation, is beneficial to the extraction of subsequent active ingredients, and improves the effects of eliminating phlegm and relieving asthma of the extract; the preferred power program is adopted for extraction, the active ingredients of the peucedanum praeruptorum are fully extracted, the transrate of the praeruptorin A, the transrate of the peucedanum B and the transrate of the total coumarin are obviously improved, and the effects of eliminating phlegm and relieving asthma of the extract are obviously improved; the ethanol concentration is optimized, the active ingredients of the peucedanum praeruptorum in the filter residue are effectively extracted, the transporation rate of the praeruptorin A, the transporation rate of the peucedanum B and the transporation rate of the total coumarin are obviously improved, and the effects of eliminating phlegm and relieving asthma of the extract are obviously reduced; the preferred elution program is adopted, the elution effect is improved, and the phlegm eliminating and asthma relieving effects of the extract are obviously improved.

Detailed Description

In order to better understand the technical content of the invention, specific examples are provided below to further illustrate the invention.

The experimental methods used in the examples of the present invention are all conventional methods unless otherwise specified.

The materials, reagents and the like used in the examples of the present invention can be obtained commercially without specific description.

Example 1

The preparation method of the peucedanum praeruptorum extract comprises the following specific steps:

(1) pretreatment: crushing the Chinese medicinal material peucedanum praeruptorum, grinding into powder, sieving by a 100-mesh sieve to obtain peucedanum praeruptorum powder, placing the peucedanum praeruptorum powder in an ethanol solution with the mass concentration of 65%, wherein the mass volume ratio kg/L of the peucedanum praeruptorum powder to the ethanol solution is 1: 2.5, fermenting at 38 ℃ for 90min to obtain a fermentation mixture;

(2) primary extraction: placing the fermentation mixture obtained in the step (1) in microwave extraction, firstly extracting for 45min under the condition of 350W power, then extracting for 25min under the condition of 600W power, filtering to obtain microwave extracting solution and filter residue, and concentrating the microwave extracting solution until the solid content is 55% to obtain microwave extracting concentrated solution;

(3) secondary extraction: heating and extracting the filter residue obtained in the step (2) in an ethanol solution with the mass concentration of 65% for 3 times, wherein the usage amount of the ethanol solution for the 1 st time is 4 times of the weight of the filter residue, the usage amount of the ethanol solution for the 2 nd time is 5 times of the weight of the filter residue, and the usage amount of the ethanol solution for the 3 rd time is 6 times of the weight of the filter residue, refluxing for 1 hour each time, filtering, combining the filtrates, recovering ethanol under reduced pressure, and concentrating until the solid content is 55%, thereby obtaining a reflux extraction concentrated solution;

(4) gradient elution: mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, wherein the dosage of the macroporous resin is 1 time of the weight of the decursite powder, eluting by using 45 wt% ethanol solution with 10 column volumes, eluting by using 85 wt% ethanol solution with 10 column volumes, and finally collecting 65 wt% ethanol solution eluent, wherein the flow rate of the eluent is 9 mL/min;

(5) concentrating the eluate under reduced pressure to obtain fluid extract with relative density of 1.25(60 deg.C), and drying under reduced pressure to obtain the desired radix Peucedani extract.

Example 2

The preparation method of the peucedanum praeruptorum extract comprises the following specific steps:

(1) pretreatment: crushing the Chinese medicinal material peucedanum praeruptorum, grinding into powder, sieving by a 100-mesh sieve to obtain peucedanum praeruptorum powder, and placing the peucedanum praeruptorum powder in an ethanol solution with the mass concentration of 60%, wherein the mass volume ratio kg/L of the peucedanum praeruptorum powder to the ethanol solution is 1: 3, fermenting at 35 ℃ for 100min to obtain a fermentation mixture;

(2) primary extraction: placing the fermentation mixture obtained in the step (1) in microwave extraction, firstly extracting for 50min under the condition of 300W power, then extracting for 30min under the condition of 550W power, filtering to obtain microwave extracting solution and filter residue, and concentrating the microwave extracting solution until the solid content is 50% to obtain microwave extracting concentrated solution;

(3) secondary extraction: heating and extracting the filter residue obtained in the step (2) in an ethanol solution with the mass concentration of 60% for 3 times, wherein the usage amount of the ethanol solution at the 1 st time is 4 times of the weight of the filter residue, the usage amount of the ethanol solution at the 2 nd time is 5 times of the weight of the filter residue, and the usage amount of the ethanol solution at the 3 rd time is 6 times of the weight of the filter residue, refluxing for 0.8h each time, filtering, combining the filtrates, recovering ethanol under reduced pressure, and concentrating until the solid content is 50%, so as to obtain a reflux extraction concentrated solution;

(4) gradient elution: mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, wherein the dosage of the macroporous resin is 0.8 times of the weight of the decursite powder, eluting by using 10 column volumes of 40 wt% ethanol solution, eluting by using 10 column volumes of 80 wt% ethanol solution, and collecting 60 wt% ethanol solution eluent with the eluent flow rate of 8 mL/min;

(5) concentrating the eluate under reduced pressure to obtain fluid extract with relative density of 1.25(60 deg.C), and drying under reduced pressure to obtain the desired radix Peucedani extract.

Example 3

The preparation method of the peucedanum praeruptorum extract comprises the following specific steps:

(1) pretreatment: crushing the Chinese medicinal material peucedanum praeruptorum, grinding into powder, sieving by a 100-mesh sieve to obtain peucedanum praeruptorum powder, and placing the peucedanum praeruptorum powder in an ethanol solution with the mass concentration of 70%, wherein the mass volume ratio kg/L of the peucedanum praeruptorum powder to the ethanol solution is 1: 2, fermenting at 40 ℃ for 80min to obtain a fermentation mixture;

(2) primary extraction: placing the fermentation mixture obtained in the step (1) in microwave extraction, firstly extracting for 40min under the condition of 400W power, then extracting for 20min under the condition of 650W power, filtering to obtain microwave extracting solution and filter residue, and concentrating the microwave extracting solution until the solid content is 60% to obtain microwave extracting concentrated solution;

(3) secondary extraction: heating and extracting the filter residue obtained in the step (2) in an ethanol solution with the mass concentration of 70% for 3 times, wherein the usage amount of the ethanol solution at the 1 st time is 4 times of the weight of the filter residue, the usage amount of the ethanol solution at the 2 nd time is 5 times of the weight of the filter residue, and the usage amount of the ethanol solution at the 3 rd time is 6 times of the weight of the filter residue, refluxing for 1.2h each time, filtering, combining the filtrates, recovering ethanol under reduced pressure, and concentrating until the solid content is 60% to obtain a reflux extraction concentrated solution;

(4) gradient elution: mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, wherein the dosage of the macroporous resin is 1.2 times of the weight of the decursite powder, eluting by using 50 wt% ethanol solution with 10 column volumes, eluting by using 90 wt% ethanol solution with 10 column volumes, and finally collecting 70 wt% ethanol solution eluent, wherein the flow rate of the eluent is 10 mL/min;

(5) concentrating the eluate under reduced pressure to obtain fluid extract with relative density of 1.30(60 deg.C), and drying under reduced pressure to obtain the desired radix Peucedani extract.

Example 4

The preparation method of the peucedanum praeruptorum extract comprises the following specific steps:

(1) pretreatment: crushing the Chinese medicinal material peucedanum praeruptorum, grinding into powder, sieving by a 100-mesh sieve to obtain peucedanum praeruptorum powder, and placing the peucedanum praeruptorum powder in an ethanol solution with the mass concentration of 60%, wherein the mass volume ratio kg/L of the peucedanum praeruptorum powder to the ethanol solution is 1: 2, fermenting at 35 ℃ for 80min to obtain a fermentation mixture;

(2) primary extraction: placing the fermentation mixture obtained in the step (1) in microwave extraction, firstly extracting for 40min under the condition of power of 320W, then extracting for 20min under the condition of power of 580W, filtering to obtain microwave extracting solution and filter residue, and concentrating the microwave extracting solution until the solid content is 55% to obtain microwave extracting concentrated solution;

(3) secondary extraction: heating and extracting the filter residue obtained in the step (2) in an ethanol solution with the mass concentration of 70% for 3 times, wherein the usage amount of the ethanol solution for the 1 st time is 4 times of the weight of the filter residue, the usage amount of the ethanol solution for the 2 nd time is 5 times of the weight of the filter residue, and the usage amount of the ethanol solution for the 3 rd time is 6 times of the weight of the filter residue, refluxing for 1 hour each time, filtering, combining the filtrates, recovering ethanol under reduced pressure, and concentrating until the solid content is 55%, thereby obtaining a reflux extraction concentrated solution;

(4) gradient elution: mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, wherein the dosage of the macroporous resin is 1 time of the weight of the decursite powder, eluting by using 50 wt% ethanol solution with 10 column volumes, eluting by using 80 wt% ethanol solution with 10 column volumes, and finally collecting 65 wt% ethanol solution eluent, wherein the flow rate of the eluent is 10 mL/min;

(5) concentrating the eluate under reduced pressure to obtain fluid extract with relative density of 1.25(60 deg.C), and drying under reduced pressure to obtain the desired radix Peucedani extract.

Comparative example 1

The main difference from the example 1 is that in the step (1), the mixture is placed in an ethanol solution with the mass concentration of 50% for fermentation for 120 min. Specifically, the pretreatment: crushing the Chinese medicinal material peucedanum praeruptorum, grinding into powder, sieving by a 100-mesh sieve to obtain peucedanum praeruptorum powder, and placing the peucedanum praeruptorum powder in an ethanol solution with the mass concentration of 50%, wherein the mass volume ratio kg/L of the peucedanum praeruptorum powder to the ethanol solution is 1: 2.5, fermenting at 38 ℃ for 120min to obtain a fermentation mixture.

Comparative example 2

The main difference from the example 1 is that in the step (2), the extraction is carried out for 60min under the condition of 500W power. Specifically, the first extraction: and (2) placing the fermentation mixture obtained in the step (1) in a microwave extraction mode for 60min, setting the microwave power to be 500W, filtering to obtain a microwave extracting solution and filter residues, and concentrating the microwave extracting solution until the solid content is 55% to obtain a microwave extracting concentrated solution.

Comparative example 3

The main difference from example 1 is that in step (3), the concentration of the ethanol solution as the extraction solvent and the amount thereof are adjusted. Specifically, secondary extraction: and (3) placing the filter residue in the step (2) into an ethanol solution with the mass concentration of 80%, heating and extracting for 3 times, wherein the usage amount of the ethanol solution for each heating and extraction is 5 times of the weight of the filter residue, refluxing for 1 hour each time, filtering, combining the filtrates, recovering ethanol under reduced pressure, and concentrating until the solid content is 55% to obtain a reflux extraction concentrated solution.

Comparative example 4

The main difference from example 1 is that in step (4), the elution procedure is adjusted. The specific gradient elution steps are as follows: and (3) mixing the concentrated solutions obtained in the steps (2) and (3), adding the mixed solution into macroporous resin, eluting the macroporous resin by using 55 v/v% ethanol solution with 10 column volumes, wherein the dosage of the macroporous resin is 1 time of the weight of the decursite powder, and finally collecting 75 v/v% ethanol solution eluent, wherein the flow rate of the eluent is 9 mL/min.

Detection of active ingredients

The peucedanum praeruptorum dunn extracts prepared in the examples 1-4 and the comparative examples 1-4 (which are prepared by adopting the same batch of peucedanum praeruptorum dunn traditional Chinese medicinal materials) are used for detecting the contents of effective components of praeruptorin A, praeruptorin B and total coumarin. Detecting the contents of praeruptorin A and praeruptorin B by HPLC according to Chinese pharmacopoeia, and detecting with chromatographic column of Dikma Diamond-C18 (4.6mm × 250mm, 5 μm) at detection wavelength of 321 nm; the total coumarin content was determined spectrophotometrically at 348 nm. And calculating the transfer rate of the effective components, wherein the transfer rate is the content (mg) of the effective components in the extract/the content (mg) multiplied by 100 percent of the effective components in the original medicinal materials.

The results are as follows:

the results show that the transfer rates of the praeruptorin A, the peucedanin B and the total coumarin are obviously improved in the examples 1 to 4 compared with the comparative examples 1 to 4.

Comparative example 1 reduces the concentration of the fermentation ethanol solution, prolongs the fermentation time, reduces the fermentation effect, and is not beneficial to the extraction of subsequent active ingredients; comparative example 2 does not adopt the preferred power procedure of the invention to extract, the microwave extraction effect is obviously reduced, the active ingredients of the peucedanum root can not be fully extracted, the transptance of the peucedanum root A and the transptance of the peucedanum root B are obviously reduced, and the transptance of coumarin is also reduced; comparative example 3 does not adopt the method of the invention to optimize the ethanol concentration, the reflux extraction effect is reduced, the active ingredients of the peucedanum praeruptorum in the filter residue can not be effectively extracted, the transptance of the peucedanum A and the transptance of the peucedanum B are obviously reduced, and the transptance of the coumarin is also obviously reduced; comparative example 4 the elution effect was reduced without the preferred elution procedure of the present invention.

Second, mouse test

(1) Test of expectorant Effect

The expectorant effect of the radix peucedani extract is evaluated by adopting a mouse phenol red method and taking the excretion amount of the phenol red tracheae as an index.

90 screened qualified ICR mice with the weight of 18-22g are selected and randomly divided into 9 groups, each group comprises 10 mice and each half of the mice is male and female. Each daily dose is 4.50g/kg, the stomach is continuously gavaged for 5 days, 30min after the last dose, 5% phenol red solution is injected into the abdominal cavity for 0.1mL/10g, the animals are immediately killed after 30min, the trachea is stripped, the animals are placed into a test tube of 2mL physiological saline, 1mmol of NaOH0.1mL is added, and the trachea is discarded after shaking and even mixing. OD was measured with a model 721 spectrophotometer at a wavelength of 546 nm. Phenol red was used as a standard curve to calculate the phenol red content (μ g/mL) and compared to a blank control (given the same amount of deionized water) for statistical treatment. The results are as follows:

p <0.05, P <0.01, compared to the blank control group

The results show that the expectorant effect of the peucedanum root extract of examples 1-4 is significantly improved compared with the blank control group.

(2) Test of asthma relieving effect

90 screened qualified guinea pigs with the weight of 180-. Each of the drugs was orally administered at a dose of 4.50g/kg daily 1 time a day for 3 consecutive days, and the control group was administered with the same amount of deionized water. 40 minutes after the last administration, each animal was placed in a spray device, a 0.2% histamine phosphate solution was sprayed at a constant rate for 18 seconds using a cough-inducing asthma-inducing apparatus, and the asthma-inducing latency of the guinea pigs was recorded. The mean values obtained for each group were compared with the mean values of the control group and subjected to statistical tests.

The results are as follows:

p <0.05, P <0.01, compared to the blank control group

The results show that the extracts of peucedanum praeruptorum of examples 1-4 significantly prolonged the asthma-inducing latency of guinea pigs, compared to the blank control group.

In conclusion, the comparative example 1 reduces the concentration of the fermentation ethanol solution, prolongs the fermentation time, reduces the fermentation effect, is not beneficial to the subsequent extraction of active ingredients, and reduces the phlegm eliminating and asthma relieving effects of the extract; comparative example 2 the preferred power program of the invention is not adopted for extraction, the microwave extraction effect is obviously reduced, the active ingredients of the peucedanum root can not be fully extracted, and the phlegm eliminating and asthma relieving effects of the extract are obviously reduced; comparative example 3 no ethanol concentration is optimized by adopting the method, the reflux extraction effect is reduced, the active ingredients of the peucedanum praeruptorum in the filter residue can not be effectively extracted, and the phlegm eliminating and asthma relieving effects of the extract are obviously reduced; comparative example 4 without the preferred elution procedure of the present invention, the elution effect was decreased, and the expectorant and antiasthmatic effects of the extract were both significantly decreased.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.