Thin-layer identification method for portulaca oleracea and preparation thereof

Abstract

The invention discloses a thin-layer identification method of purslane and a preparation thereof, which comprises the following steps of: obtaining a test solution and a reference medicinal material solution by adopting a simple, convenient and rapid pretreatment method, respectively dripping the test solution and the reference medicinal material solution on the same thin-layer plate, and developing by taking cyclohexane-dichloromethane-ethyl acetate-formic acid as a developing solvent to obtain a multi-information purslane thin-layer chromatogram. The method is simple, convenient and rapid to operate, good in chromatographic spot separation degree, suitable for identifying the purslane and the preparation thereof and capable of distinguishing true and false products, and has the characteristics of specificity, low detection cost, safety in operation and more environment-friendly reagents.

Description

Technical Field

[0001] The invention relates to the field of quality control of traditional Chinese medicines, and in particular to a thin layer identification method for purslane and a preparation thereof. Background Art

[0002] Purslane is the dried aerial part of the plant Portulaca oleracea L. of the Portulacaceae family. It is sour and cold in nature, and has the effects of clearing away heat and detoxifying, cooling blood and stopping bleeding, and stopping dysentery. It is used for heat-toxic bloody dysentery, carbuncle furuncle, eczema, erysipelas, snake and insect bites, blood in the stool, hemorrhoids, metrorrhagia and other symptoms. Modern pharmacological studies have found that Purslane has antibacterial, antiviral, lipid-lowering, and anti-atherosclerotic effects. Its chemical components are mainly organic acids, alkaloids, flavonoids, lignans, etc.

[0003] The existing reports on the identification method of purslane by thin layer chromatography mainly focus on the identification method of purslane medicinal materials included in the 2020 edition of the Chinese Pharmacopoeia. However, the pretreatment of this method takes a long time, the identification substance is an amino acid component, the specificity is poor, and amino acids are present in many botanicals. In addition, the chromatographic spot separation is poor, which can easily lead to misjudgment and make it impossible to accurately perform qualitative identification. The thin layer chromatography identification methods of purslane in some other preparations reported in the literature (Hou Yinhuan. Study on the Chemical Composition and Quality Evaluation of Purslane [D]. Shenyang Pharmaceutical University, 2008.; Sharina et al. Establishment of the Quality Standard of Healing King Preparation [J]. Chinese Pharmacist, 2016, 19(11): 2165-2167.) all use toxic and harmful solvents such as benzene, toluene, and chloroform, which have an adverse impact on the environment and the safety of the experimenters. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to provide a thin layer identification method and application of purslane and its preparations.

[0005] Technical solution: The thin layer identification method of purslane and its preparation provided by the present invention comprises the following steps:

[0006] (1) preparing a purslane test sample solution, wherein the purslane test sample includes purslane medicinal materials, purslane formula granules and purslane standard decoction;

[0007] (2) preparing a control medicinal material solution of purslane;

[0008] (3) Spot the purslane test sample solution and the purslane control drug solution on the same thin layer plate, develop with cyclohexane-dichloromethane-ethyl acetate-formic acid as the developing agent, take out, and examine under ultraviolet light.

[0009] Furthermore, in step (1), when the purslane test sample is purslane medicinal material, the preparation process of the purslane test sample solution, or the preparation process of the purslane control medicinal material solution in step (2) is: taking purslane medicinal material, decocting with water or heating and refluxing, filtering, adding ethyl acetate to the filtrate and shaking to extract, standing and stratifying, combining the ethyl acetate layers, evaporating to dryness, and dissolving the residue in an alcohol solvent to obtain;

[0010] Or take purslane medicinal material, add water to boil or heat reflux treatment, filter, add methanol to the residue, ultrasonic treatment, filter, evaporate the filtrate to dryness, add methanol to the residue to dissolve, and obtain the product.

[0011] Furthermore, the mass volume ratio of the purslane medicinal material to water is 1:50g / mL to 200g / mL, the decoction or heating reflux treatment time is 15min to 60min, the number of ethyl acetate shaking extraction is 1 to 3 times, and the volume ratio of the ethyl acetate solution to the sample's aqueous solution is 0.5 to 2:1.

[0012] Furthermore, in step (1), when the purslane test sample is purslane formula granules or purslane standard decoction, the preparation process of the purslane test sample solution is: taking the purslane preparation test sample, adding water to dissolve or dilute it, adding ethyl acetate to shake and extract, standing to separate and stratify, combining the ethyl acetate layer, evaporating to dryness, and adding an alcohol solvent to dissolve the residue to obtain;

[0013] Alternatively, take a sample of the purslane preparation, add methanol or ethanol to dissolve it, perform ultrasonic treatment, filter it, evaporate the filtrate to dryness, and add an alcohol solvent to dissolve the residue to obtain the product.

[0014] Furthermore, the mass volume ratio of the test sample to water is 1:20 g / mL~50 g / mL, the power of ultrasonic treatment is 250 W~600 W, the frequency is 30 kHz~50 kHz, the time is 15 min~60 min, the number of ethyl acetate shaking extraction is 1 to 3 times, and the volume ratio of ethyl acetate solution to the sample aqueous solution is 0.5~2:1.

[0015] Furthermore, the thin layer plate in step (3) is a silica gel plate.

[0016] Furthermore, in step (3), the volume ratio of cyclohexane-dichloromethane-ethyl acetate-formic acid is (3-5):(0.5-1.5):(3-5):0.1.

[0017] Furthermore, in step (3), the spotting volume of the test solution is 2 μl to 10 μl, and the spotting volume of the control medicinal material solution is 5 μl to 15 μl.

[0018] Furthermore, in step (3), the wavelength of the ultraviolet lamp is 360-370 nm.

[0019] The present invention also provides application of the thin layer identification method of the purslane and the preparation thereof in distinguishing genuine products from counterfeit products.

[0020] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the present invention adopts a simple and quick pretreatment method to obtain a test solution and a control medicinal material solution, which are respectively spotted on the same thin layer plate, and developed with cyclohexane-dichloromethane-ethyl acetate-formic acid as a developing agent to obtain a multi-information thin layer chromatogram of purslane. The method is simple and fast to operate, and has good chromatographic spot separation. It is suitable for the identification of purslane and its preparations, and can distinguish between genuine and fake products. It has the characteristics of specificity, low detection cost, safe operation, and more environmentally friendly reagents. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a thin layer chromatogram of the purslane formula granules in Example 1 of the present invention (wherein, 1 to 3 are chromatograms of test samples of different batches of purslane formula granules, and S is a chromatogram of the purslane reference medicinal material);

[0022] Figure 2 is a thin layer chromatogram of the standard decoction of purslane in Example 1 of the present invention (wherein, 1 to 3 are chromatograms of test samples of different batches of standard decoction of purslane, and S is a chromatogram of the reference medicinal material of purslane);

[0023] Figure 3 is a thin layer chromatogram of the purslane medicinal material in Example 1 of the present invention (wherein 1 to 3 are chromatograms of test samples of different batches of purslane medicinal materials, and S is a chromatogram of the purslane control medicinal material);

[0024] Figure 4 is a thin layer chromatogram of different developing agent ratios in Example 2 of the present invention (wherein, 1 to 3 are chromatograms of test samples of different batches of Portulaca oleracea medicinal materials, and S is a chromatogram of a control Portulaca oleracea medicinal material);

[0025] Figure 5 It is a thin layer chromatogram of different sample amounts in Example 2 of the present invention (wherein, 1 to 4 are chromatograms of different sample amounts of purslane formula granules for test, and S1 to S4 are chromatograms of different sample amounts of purslane reference medicinal materials);

[0026] Figure 6 are the thin layer chromatograms at different temperatures in Example 2 of the present invention (wherein 1 to 3 are the chromatograms of the test sample of the purslane formula granules, and S is the chromatogram of the purslane reference medicinal material);

[0027] Figure 7 is the thin layer chromatogram of different humidity in Example 2 of the present invention (wherein, 1 to 3 are the chromatograms of the test sample of the purslane formula granules, and S is the chromatogram of the purslane reference medicinal material);

[0028] Figure 8is a thin layer chromatogram for authenticity identification of the purslane medicinal material and the counterfeit Herba Coptidis in Example 3 of the present invention (wherein, 1 to 3 are chromatograms of test samples of Herba Coptidis from different batches, 4 to 6 are chromatograms of test samples of different batches of purslane medicinal materials, and S is a chromatogram of the purslane control medicinal material);

[0029] Fig. 9 is a thin layer chromatogram for authenticity identification of the standard decoction of Portulaca oleracea and the counterfeit standard decoction of Herba Crepisae in Example 3 of the present invention (wherein, 1 to 3 are chromatograms of test samples of different batches of standard decoction of Herba Crepisae, 4 to 6 are chromatograms of test samples of different batches of standard decoction of Portulaca oleracea, and S is a chromatogram of the control medicinal material of Portulaca oleracea);

[0030] Fig.10 It is a thin layer chromatogram of the test solution and the control medicinal material solution of the purslane formula granules prepared by different methods in Comparative Example 1 of the present invention (wherein, 1 to 3 are the test sample chromatograms of the purslane formula granules prepared by the three preparation methods, and S1 to S3 are the purslane control medicinal material chromatograms prepared by the three preparation methods);

[0031] Fig.11 It is a thin layer chromatogram of the purslane formula granules with different identification methods in Comparative Example 2 of the present invention (wherein, the left figure adopts the thin layer developing agent under the purslane item in Volume 1 of the 2020 edition of the "Chinese Pharmacopoeia": water-saturated n-butanol-glacial acetic acid-water (4:1:1), and the color developer is 0.2% ninhydrin ethanol solution; the right figure adopts the developing agent reported in the literature: toluene-chloroform-ethyl formate-formic acid (5:1:11:1)). DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0033] The present invention adopts the following instruments and reagents:

[0034] Instruments: CAMAG TLC VISUALIZER, 1 / 10,000 balance (Mettler-Toledo), KQ-250E ultrasonic cleaner (Kunshan Ultrasonic Electronics Co., Ltd.), GKC temperature-controlled water bath (Nantong Huatai Experimental Instrument Co., Ltd.), TH-Ⅱ CNC thin layer chromatography heater (Shanghai Kezhe Biochemical Technology Co., Ltd.), high-efficiency silica gel G thin layer plate (Qingdao Ocean Chemical Plant).

[0035] Reagents: methanol (Shanghai Titan Technology Co., Ltd.), ethanol (Sinopharm Chemical Reagent Co., Ltd.), ethyl acetate (Sinopharm Chemical Reagent Co., Ltd.), cyclohexane (Sinopharm Chemical Reagent Co., Ltd.), dichloromethane (Sinopharm Chemical Reagent Co., Ltd.), n-butanol (Sinopharm Chemical Reagent Co., Ltd.), glacial acetic acid (Sinopharm Chemical Reagent Co., Ltd.), toluene (Shanghai Lingfeng Chemical Reagent Co., Ltd.), chloroform (Shanghai Lingfeng Chemical Reagent Co., Ltd.), ethyl formate (Shanghai Titan Technology Co., Ltd.), formic acid (Shanghai Titan Technology Co., Ltd.) were all analytical grade;

[0036] The control herbal medicine of Purslane (batch number: 121598-202004) was purchased from China Food and Drug Inspection Institute;

[0037] Test samples: Purslane formula granules (batch numbers: 24060019, 24060029, 24060039), Purslane standard decoction (batch numbers: DG2202009, DG1012404008, DG1012404010), Purslane medicinal materials (batch numbers: YC2202009, YC1012404008, YC1012404010), Herba Crepisae standard decoction (batch numbers: DG1804157, DG1807040, DG1807105), Herba Crepisae medicinal materials (batch numbers: YC1804157, YC1807040, YC1807105) were all provided by Jiangyin Tianjiang Pharmaceutical Co., Ltd.

[0038] If no specific experimental steps or conditions are specified in the present invention, the conventional experimental steps or conditions described in the literature in the art can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be purchased commercially.

[0039] Example 1: Thin layer identification method of Portulaca oleracea

[0040] Preparation of test sample solution / control sample solution: Take 1 g of Portulaca oleracea test sample / control sample, add 50 ml of water, heat and reflux for 30 minutes, filter, concentrate the filtrate to about 20 ml, shake and extract with ethyl acetate twice, 20 ml each time, combine the ethyl acetate solutions, evaporate to dryness, add 1 ml of methanol to dissolve the residue, and use it as the test sample solution / control sample solution.

[0041] Preparation of test solution for preparation (the preparation method of test solution for formula granules and standard decoction is the same): take 0.5g of this product, grind it into powder, add 20ml of water to dissolve it, shake and extract it with ethyl acetate twice, 20ml each time, combine the ethyl acetate solution, evaporate to dryness, add 1ml of methanol to dissolve the residue, and use it as the test solution for preparation.

[0042] Thin layer identification steps: According to the thin layer chromatography method (General Rules 0502 of the 2020 edition of the Chinese Pharmacopoeia), 5 μl of the test sample solution and 10 μl of the control medicinal material solution were respectively spotted on the same high-efficiency silica gel G thin layer plate, and cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) was used as the developing agent. After development, the plate was taken out, dried, and inspected under ultraviolet light (365 nm).

[0043] Evaluation requirements: In the chromatogram of the test sample, fluorescent spots of the same color appear at the corresponding positions in the chromatogram of the control medicinal material.

[0044] Result analysis: Figure 1 1 to 3 are the chromatograms of the test samples of different batches of Purslane formula granules, and S is the chromatogram of the reference medicinal material Purslane. Figure 2 1 to 3 are the chromatograms of test samples from different batches of standard decoction of Portulaca oleracea, and S is the chromatogram of the reference medicinal material of Portulaca oleracea. Figure 3 1 to 3 are the chromatograms of the test products of different batches of purslane medicinal materials, and S is the chromatogram of the purslane control medicinal material. The chromatograms of purslane medicinal materials, standard decoctions, and formula granules are all compared with the chromatogram of the control medicinal material. Fluorescent spots of the same color appear at the same position, indicating that they are all qualified products.

[0045] Example 2: Durability study of the thin layer identification method for purslane

[0046] (1) Investigation of different developing agent ratios:

[0047] Take purslane formula granules (batch number: 24060029) and purslane control medicinal materials, and prepare test solution and control medicinal material solution according to the method described in Example 1, respectively. Take 5 μl of purslane formula granule test solution and 10 μl of purslane control medicinal material solution, respectively, and spot them on the same high-efficiency silica gel G thin layer plate, use cyclohexane-dichloromethane-ethyl acetate-formic acid (3:0.5:3:0.1), (4:1:4:0.1), (5:1.5:5:0.1), (6:2:6:0.1) as developing agent, develop, take out, dry, and inspect under ultraviolet lamp (365nm).

[0048] Results Figure 4 , Figure 4 1 to 3 correspond to the chromatograms of the test purslane formula granules, and S corresponds to the chromatogram of the reference purslane. Figure 4It can be seen that under different developing agent ratios, the chromatogram of the sample of the purslane formula granules and the chromatogram of the control medicinal material show fluorescent spots of the same color at the corresponding positions. When the volume ratio of cyclohexane-dichloromethane-ethyl acetate-formic acid is (3-5): (0.5-1.5): (3-5): 0.1, the separation of the fluorescent spots is better and the spectrum is more beautiful. Therefore, the subsequent experiments use a volume ratio of cyclohexane-dichloromethane-ethyl acetate-formic acid of 4:1:4:0.1 for further investigation.

[0049] (2) Investigation of different sample quantities:

[0050] Take purslane formula granules (batch number: 24060029) and purslane control medicinal materials, and prepare test solution and control medicinal material solution according to the method described in Example 1, respectively. Take 2μl, 5μl, 8μl, 10μl of purslane formula granule test solution and 5μl, 8μl, 10μl, 15μl of purslane control medicinal material solution, respectively, and spot them on the same high-efficiency silica gel G thin layer plate, use cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) as the developing agent, develop, take out, dry, and examine under ultraviolet light (365nm).

[0051] Results Figure 5 , Figure 5 1 to 4 correspond to the chromatograms of 2μl, 5μl, 8μl, and 10μl of the purslane formula granules test sample, and S1 to S4 correspond to the chromatograms of 5μl, 8μl, 10μl, and 15μl of the purslane reference medicinal material, respectively. Figure 5 It can be seen that when the sample solution spot volume is 2μl~10μl and the control medicinal material solution spot volume is 5μl~15μl, the fluorescent spots in the test sample chromatogram and the control medicinal material chromatogram at the corresponding positions are clear, without other interference, and can correspond one to one.

[0052] (3) Investigation at different temperatures

[0053] Take purslane formula granules (batch number: 24060029) and purslane control medicinal materials, and prepare test solution and control medicinal material solution according to the method described in Example 1, respectively. Take 5 μl of purslane formula granule test solution and 10 μl of purslane control medicinal material solution, respectively, and spot them on the same high-efficiency silica gel G thin layer plate, use cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) as the developing agent, and develop them at different temperatures (T: 4°C, 19.6°C, 35°C), take out, dry, and examine under ultraviolet light (365nm).

[0054] Results Figure 6 , Figure 6 1 to 3 correspond to the chromatograms of the test purslane formula granules, and S corresponds to the chromatogram of the reference purslane. Figure 6 It can be seen that under different temperature conditions, the chromatograms of the sample of the purslane formula granules and the chromatograms of the control medicinal materials show fluorescent spots of the same color at the corresponding positions. The experimental results show that temperature has no significant effect on the thin layer identification of the purslane formula granules, indicating that the thin layer identification method has good durability at different temperatures.

[0055] (4) Investigation of different humidity levels

[0056] Take purslane formula granules (batch number: 24060029) and purslane control medicinal materials, and prepare test solution and control medicinal material solution according to the method described in Example 1, respectively. Take 5 μl of purslane formula granule test solution and 10 μl of purslane control medicinal material solution, respectively, and spot them on the same high-efficiency silica gel G thin layer plate, use cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) as the developing agent, and develop them under different humidity conditions (RH: 18%, 58.1%, 88%), take out, dry, and examine under ultraviolet light (365nm).

[0057] Results Figure 7 , Figure 7 1 to 3 correspond to the chromatograms of the test purslane formula granules, and S corresponds to the chromatogram of the reference purslane. Figure 7 It can be seen that under different humidity conditions, the chromatograms of the sample of the purslane formula granules and the chromatograms of the control medicinal materials show fluorescent spots of the same color at the corresponding positions. The experimental results show that humidity has no significant effect on the thin layer identification of the purslane formula granules, indicating that the thin layer identification method has good durability under different humidity conditions.

[0058] Example 3 Identification of Purslane and its preparations from counterfeits

[0059] (1) Identification of Portulaca oleracea and its counterfeit counterpart (Pursula oleracea)

[0060] Take Herba Lysimachiae, Herba Portulacae as test material, and Herba Portulacae as control material, and prepare test solution and control material solution respectively according to the method described in Example 1, and take 10 μl of Herba Lysimachiae test solution, Herba Portulacae as test material, and Herba Portulacae as control material solution respectively, and spot them on the same high-efficiency silica gel G thin layer plate, use cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) as the developing agent, develop, take out, dry, and examine under ultraviolet lamp (365nm).

[0061] Results Figure 8 , Figure 8 1 to 3 correspond to the chromatograms of the test samples of Herba Coptidis, 4 to 6 correspond to the chromatograms of the test samples of Herba Portulacae, and S corresponds to the chromatogram of the control Herba Portulacae. Figure 8It can be seen that the fluorescent spots of Portulaca oleracea medicinal materials and Portulaca oleracea control medicinal materials correspond one to one. There is a yellow fluorescent spot above the thin layer chromatogram of Herba Lycopersicon esculenta medicinal materials, which is inconsistent with the spot of Portulaca oleracea control medicinal materials. Therefore, this thin layer identification is effective in distinguishing Portulaca oleracea medicinal materials from counterfeit Herba Lycopersicon esculenta medicinal materials.

[0062] (2) Identification of standard decoction of Portulaca oleracea and counterfeit standard decoction (Pursula oleracea)

[0063] Take the standard decoction of Herba Crepisae, the standard decoction of Portulaca oleracea, and the control medicinal material of Portulaca oleracea, and prepare the test solution and the control medicinal material solution according to the method described in Example 1, respectively. Take 5 μl of the test solution of the standard decoction of Herba Crepisae, 5 μl of the test solution of the standard decoction of Portulaca oleracea, and 10 μl of the control medicinal material solution of Portulaca oleracea, respectively, and spot them on the same high-efficiency silica gel G thin layer plate, use cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) as the developing agent, develop, take out, dry, and examine under ultraviolet light (365nm).

[0064] Results Fig. 9 , Fig. 9 1 to 3 correspond to the chromatograms of the standard decoction of Herba Coptidis, 4 to 6 correspond to the chromatograms of the standard decoction of Herba Portulacae, and S corresponds to the chromatogram of the reference herbal medicine Herba Portulacae. Fig. 9 It can be seen that the fluorescent spots of the Portulaca oleracea standard decoction and the Portulaca oleracea control medicinal material correspond one to one, and there is a yellow fluorescent spot above the thin layer chromatogram of the standard decoction of Herba Creepingii, which is inconsistent with the spot of the Portulaca oleracea control medicinal material. Therefore, this thin layer identification is effective in distinguishing the standard decoction of Portulaca oleracea from the counterfeit standard decoction of Herba Creepingii.

[0065] Comparative Example 1:

[0066] This comparative example investigates different methods for preparing test sample and control medicinal material solutions, as follows:

[0067] (1) Investigation of different preparation methods of the test solution of Purslane formula granules (batch number: 24060029):

[0068] Method 1: Take 0.5 g of the product, grind it into powder, add 20 ml of methanol, and treat it with ultrasound (power 600 W, frequency 40 kHz) for 30 minutes. Filter, evaporate the filtrate to dryness, and add 1 ml of methanol to the residue to dissolve it as the test solution.

[0069] Method 2: Take 0.5 g of this product, grind it into powder, add 20 ml of ethanol, and treat it with ultrasound (power 600 W, frequency 40 kHz) for 30 minutes. Filter, evaporate the filtrate to dryness, and add 1 ml of ethanol to dissolve the residue as the test solution.

[0070] Method 3: Take 0.5g of this product, grind it into powder, add 20ml of water to dissolve it, shake and extract it twice with ethyl acetate, 20ml each time, combine the ethyl acetate liquid, evaporate to dryness, add 1ml of methanol to dissolve the residue, and use it as the test solution.

[0071] (2) Investigation of different preparation methods of purslane control medicinal material solution:

[0072] Method 1: Take 1 g of Portulaca oleracea as a control medicinal material, add 20 ml of methanol, and treat with ultrasound (power 600 W, frequency 40 kHz) for 30 minutes. Filter, evaporate the filtrate to dryness, and add 1 ml of methanol to the residue to dissolve it as the control medicinal material solution.

[0073] Method 2: Take 1 g of Portulaca oleracea as a control medicinal material, add 50 ml of water, heat and reflux for 30 minutes, filter, concentrate the filtrate to near dryness, add 20 ml of methanol to the residue, ultrasonically treat (power 600 W, frequency 40 kHz) for 30 minutes, filter, evaporate the filtrate, add 1 ml of methanol to the residue to dissolve it, and use it as the control medicinal material solution.

[0074] Method 3: Take 1 g of Portulaca oleracea as a control medicinal material, add 50 ml of water, heat and reflux for 30 minutes, filter, concentrate the filtrate to about 20 ml, shake and extract with ethyl acetate twice, 20 ml each time, combine the ethyl acetate liquid, evaporate to dryness, add 1 ml of methanol to the residue to dissolve it, and use it as the control medicinal material solution.

[0075] According to the thin layer chromatography method (General Rules 0502 of the 2020 edition of the Chinese Pharmacopoeia), 5 μl of the test sample solution and 10 μl of the control drug solution were respectively spotted on the same high-efficiency silica gel G thin layer plate, and cyclohexane-dichloromethane-ethyl acetate-formic acid (4:1:4:0.1) was used as the developing agent. The plate was developed, taken out, dried, and examined under ultraviolet light (365 nm).

[0076] Result analysis: Fig.10 1 to 3 are the chromatograms of the test products of the purslane formula granules prepared by the three preparation methods, and S1 to S3 are the chromatograms of the purslane reference medicinal materials prepared by the three preparation methods. Fig.10 It can be seen that the fluorescent spots of the samples prepared by the three test solution preparation methods are clear and the separation effect is good.

[0077] The preparation method 1 of the control medicinal material solution has more pigments, which affects the inspection of the fluorescent spots. The chromatographic spots of the preparation methods 2 and 3 of the control medicinal material solutions are clearer and have better separation effects. In order to reduce the influence of pigments, the convenience of spotting is taken into account, and the consistency of the preparation methods of the test solution and the control medicinal material solution is ensured. Therefore, the test method 3 is selected as the best treatment method for the purslane formula granules test sample, and the control medicinal material method 3 is selected as the best treatment method for the purslane control medicinal material and the test medicinal material.

[0078] Comparative Example 2:

[0079] This comparative example compares different thin layer detection developing agents, as follows:

[0080] (1) Developing agent for thin layer testing under the item of Portulaca oleracea in the 2020 edition of the Chinese Pharmacopoeia (General Principles 0502 of the 2020 edition of the Chinese Pharmacopoeia)

[0081] 1-2 μl of the purslane test sample (formulated granules) solution and the control medicinal material solution prepared by the method of Example 1 were taken and spotted on the same silica gel G thin layer plate, respectively, and water-saturated n-butanol-glacial acetic acid-water (4:1:1) was used as the developing agent. The plate was developed, taken out, dried, sprayed with 0.2% ninhydrin ethanol solution, and heated at 110°C until the spots were clearly colored.

[0082] (2) The developing agent for thin layer detection reported in the literature (Hou Yinhuan. Study on the chemical composition and quality evaluation of Portulaca oleracea [D]. Shenyang Pharmaceutical University, 2008; Sharina et al. Establishment of the quality standard of Healing King preparation [J]. Chinese Pharmacist, 2016, 19(11): 2165-2167). 5 μl of the Portulaca oleracea test sample (formulated granules) solution prepared by the method of Example 1 and 10 μl of the control medicinal material solution were respectively spotted on the same silica gel G thin layer plate, and toluene-chloroform-ethyl formate-formic acid (5:1:11:1) was used as the developing agent. Saturation was carried out for 25 minutes, and the plate was developed with a development distance of 14 cm. The plate was taken out, dried, and inspected under ultraviolet light (365 nm).

[0083] Result analysis: Fig.11 The two figures correspond to two different development systems. The developing solvent in the left figure is water-saturated n-butanol-glacial acetic acid-water (4:1:1), and the developing solvent in the right figure is toluene-chloroform-ethyl formate-formic acid (5:1:11:1). When the pharmacopoeia development system is used, the sample pretreatment takes a long time, the chromatographic spot separation is poor, it is easy to cause misjudgment, and the quality evaluation cannot be accurately performed. The development systems reported in the literature all use toxic and harmful solvents such as toluene and chloroform, which are not environmentally friendly, and have high Rf values, less spot information, and only two spots, which is not conducive to the quality evaluation of Portulaca oleracea.

Claims

1. A thin layer identification method for purslane and its preparation, characterized in that: The steps include: (1) preparing a purslane test sample solution, wherein the purslane test sample includes purslane medicinal materials, purslane formula granules and purslane standard decoction; (2) preparing a control medicinal material solution of purslane; (3) Spot the purslane test sample solution and the purslane control drug solution on the same thin layer plate, develop with cyclohexane-dichloromethane-ethyl acetate-formic acid as the developing agent, take out, and examine under ultraviolet light.

2. The thin layer identification method of purslane and its preparation according to claim 1, characterized in that: In step (1), when the purslane test sample is purslane medicinal material, the preparation process of the purslane test sample solution, or the preparation process of the purslane control medicinal material solution in step (2) is: taking purslane medicinal material, decocting with water or heating under reflux, filtering, adding ethyl acetate to the filtrate and shaking to extract, standing and separating the layers, combining the ethyl acetate layers, evaporating to dryness, and dissolving the residue in an alcohol solvent to obtain; Or take purslane medicinal material, add water to boil or heat reflux treatment, filter, add methanol to the residue, ultrasonic treatment, filter, evaporate the filtrate to dryness, add methanol to the residue to dissolve, and obtain the product.

3. The thin layer identification method of purslane and its preparation according to claim 2, characterized in that: The mass volume ratio of the purslane medicinal material to water is 1:50 g / mL to 200 g / mL, the decoction or heating reflux treatment time is 15 min to 60 min, the number of ethyl acetate shaking extraction is 1 to 3 times, and the volume ratio of the ethyl acetate solution to the sample aqueous solution is 0.5 to 2:

1.

4. The thin layer identification method of purslane and its preparation according to claim 1, characterized in that: In step (1), when the purslane test sample is purslane formula granules or purslane standard decoction, the preparation process of the purslane test sample solution is: taking the purslane preparation test sample, adding water to dissolve or dilute it, adding ethyl acetate to shake and extract, standing to separate and stratify, combining the ethyl acetate layer, evaporating to dryness, and adding an alcohol solvent to dissolve the residue to obtain; Alternatively, take a sample of the purslane preparation, add methanol or ethanol to dissolve it, perform ultrasonic treatment, filter it, evaporate the filtrate to dryness, and add an alcohol solvent to dissolve the residue to obtain the product.

5. The thin layer identification method of purslane and its preparation according to claim 4, characterized in that: The mass volume ratio of the test sample to water is 1:20g / mL~50g / mL, the power of ultrasonic treatment is 250W~600W, the frequency is 30kHz~50kHz, the time is 15min~60min, the number of ethyl acetate shaking extraction is 1~3 times, and the volume ratio of ethyl acetate solution to sample aqueous solution is 0.5~2:

1.

6. The thin layer identification method of purslane and its preparation according to claim 1, characterized in that: The thin layer plate in step (3) is a silica gel plate.

7. The thin layer identification method of purslane and its preparation according to claim 1, characterized in that: The volume ratio of cyclohexane-dichloromethane-ethyl acetate-formic acid in step (3) is (3-5):(0.5-1.5):(3-5):0.

1.

8. The thin layer identification method of purslane and its preparation according to claim 1, characterized in that: The spotting volume of the test solution in step (3) is 2 μl to 10 μl, and the spotting volume of the control medicinal material solution is 5 μl to 15 μl.

9. The thin layer identification method of purslane and its preparation according to claim 1, characterized in that: In the step (3), the wavelength of the ultraviolet lamp is 360-370nm.

10. Use of the thin layer identification method of purslane and its preparations according to claims 1 to 9 in distinguishing genuine products from counterfeit products.

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