Method for improving percolation efficiency

Abstract

The invention provides a method for improving percolation efficiency, and belongs to the technical field of traditional Chinese medicine production and food manufacturing. The technical problem to be solved by the invention is to further improve the extraction utilization rate of components by adjusting the'filling height 'of medicinal materials (plants) in a percolation container under the condition that the extraction rate of the components cannot be improved by using other technical methods and adjusting related parameters during percolation.

Description

[0001] The invention relates to a method for improving the extraction rate of Chinese medicinal materials (plants) or plant components by percolation.

[0002] Percolation is an important method for extracting components, commonly used in the traditional Chinese medicine and food industries. Percolation involves placing processed medicinal herbs (or plants) in powdered or granular form in a percolation tank. Solvent is continuously added from above, allowing the solvent to percolate through the material (plant) layer downward, extracting the components. The main advantages of this method include: dynamic top-down extraction, resulting in high leaching efficiency; extraction can be performed at room temperature, preserving heat-sensitive active ingredients; and it conserves solvent and reduces energy consumption.

[0003] The target component content extracted from the percolate (or its subsequent processing, such as concentration) is often listed in quality standards (usually statutory standards, such as those in the Chinese Pharmacopoeia). Controlling process parameters is crucial to achieving these standards. Typically, the extraction rate of the target component is achieved by controlling factors such as the fineness of the medicinal powder, the solvent (type, concentration, and dosage), the percolate flow rate, or the temperature of the percolate system.

[0004] When none of the aforementioned process control methods can produce a percolate with acceptable levels, using raw medicinal materials (plants) with particularly high levels of the target ingredient is a solution. However, this comes with prohibitively high costs and wastes medicinal material (plant) resources. Furthermore, the theoretical extraction rates achievable by the various process control methods mentioned above may require raw medicinal materials (plants) with the required levels that simply do not exist in nature. Consequently, these control processes may fail to achieve extraction rates that meet quality standards for certain ingredients, effectively resulting in substandard percolate levels.

[0005] In addition, the percolation extraction efficiency is not fully utilized, which also results in low unit medicinal material (plant) utilization rate and waste of resources. Improving efficiency can reduce the loss of medicinal material (plant) resources and reduce the generation of solid waste.

[0006] The present invention provides a method for improving percolation efficiency, which can significantly increase the content of target components in the percolation liquid. 1. Technical Field

[0007] The invention relates to a percolation extraction process for Chinese medicinal materials (plants), and belongs to the technical field of medicine and food manufacturing.

[0008] 2. Purpose of the invention:

[0009] Percolation is a common method for extracting active ingredients from traditional Chinese medicines (plants). Generally, percolation solutions containing acceptable levels of active ingredients can be obtained by adjusting the process parameters described in the legally specified process standards. However, in practice, conventional process parameter adjustments have been found to sometimes fail to fully meet quality control requirements. After researching related issues, the present invention identified key control parameters: packing height and the ratio of packing height to container cross-sectional diameter, thereby improving percolation efficiency. 3. Technical Background:

[0010] The percolation process for traditional Chinese medicine products includes multiple steps: 1) pre-treatment of the medicinal materials (plants) (such as cleaning, cutting, and crushing) to remove impurities by physical methods to obtain medicinal material (plant) properties (such as particle size) that meet the requirements of the statutory standard process; 2) percolation extraction of the target components, such as using one or more appropriate solvents (commonly water and ethanol mixed to form a solvent of a certain concentration) to separate and extract the target components in the medicinal materials (plants), and some residual components are treated as solid waste with the medicinal residue or recycled for other processes; 3) Sometimes, the crude powder (granules) of the medicinal materials (plants) are soaked before percolation.

[0011] The main parameters for percolation control include the fineness (particle size) of the medicinal powder (plant powder), the laying state of the medicinal material (plant) filler, the type of solvent, the amount of solvent used, and the flow rate.

[0012] Rhubarb fluid extract is listed in the Chinese Pharmacopoeia. The inventors, after researching and applying various conventional techniques and parameter control methods, were unable to achieve acceptable levels of target components in the percolate. Drawing on the principles of high-performance liquid chromatography and chromatographic columns, the inventors considered the percolated medicinal material as the stationary phase in the column, and the percolation solvent as the mobile phase. Therefore, percolation is similar to the elution separation process in chromatography. While chromatography separates components for easy detection, percolation extracts specific components, the two share similarities.

[0013] Further comparisons between percolation and chromatography, including column temperature and solvent temperature, stationary phase (filler type, silica particle size, etc.) and herbal matrix (rhubarb, rhubarb particle size, etc.), and mobile phase and percolation solvent, revealed that the key technical parameter controlling the potential of percolation performance is packing height. Through experimental practice, significant positive results were achieved.

[0014] On this basis, with the help of relevant knowledge of "chromatography", a possible theory is established.

[0015] Van der Muth equation: HETP = A + B / μ + C ● μ

[0016] HETP: Height of theoretical plate

[0017] A: Eddy diffusion; B: Longitudinal diffusion; C: Mass transfer resistance; μ: Mobile phase linear velocity.

[0018] Theoretical plate height is a key factor influencing column efficiency. From this equation, we can see that the factors influencing performance are summarized as packing material, packing particle size, packing filling, mobile phase solvent, and flow rate. In percolation, the packing is the medicinal material, and the mobile phase is the percolation solvent. These are typically fixed and cannot be changed for a specific variety. Optimization can be performed by factors such as the medicinal material particle size, packing efficiency (wetting and swelling, and proper layering), and flow rate (generally 1-3 ml / min per kg of medicinal material). After experimentally optimizing these parameters, the percolate content still could not meet the required standard. Therefore, the focus was on "column efficiency"—"packing height."

[0019] Simplified form of the van der Muth equation: HETP = L / N

[0020] N: number of theoretical plates; L: length of chromatographic column;

[0021] Theoretical plate height is equal to column length divided by the number of theoretical plates. Therefore, increasing the column length means increasing the height of the percolation packing.

[0022] Experiments have shown that, under certain conditions, reducing the inner diameter of the percolation vessel and increasing the packing height is effective. Another approach, however, is to increase the packing height by increasing the amount of medicinal material (plant) fed into a fixed device. This method has been applied to the percolation process for numerous medicinal materials (such as rhubarb, red peony root, and scutellaria baicalensis), with clear results.

[0023] With the deepening of theoretical thinking, further verification through experimental refinement and in-depth research, it was determined that in addition to a series of conventional technical control methods for percolation (common knowledge in the industry, available in existing papers or patents, and recorded in textbooks), "filler height" is another controllable parameter. The actual operational level is the "ratio of the filler height to the cross-sectional diameter of the percolation container." Thus, the present invention, "a method for improving percolation efficiency," was created.

[0024] IV. Claims:

[0025] Claim 1: During percolation, the "filling height" of the medicinal material (plant) in the percolation container is increased to further improve the extraction rate of the ingredients.

[0026] Claim 2: According to claim 1, the actual operation method is to increase the "ratio of the filler height to the cross-sectional diameter of the percolation container".

[0027] According to claim 1, the percolation container is a cylindrical, conical or mixed geometric body of the two forms, and its diameter (radius) refers to the diameter (radius) of its main use part, that is, the middle part (barrel body).

[0028] Claim 3: The ratio of the height of the percolation filler to the diameter of the cross-sectional area of ​​the percolation container is not less than 2.

[0029] The ratio according to claim 2, wherein the ratio of the packing height to the percolation vessel radius is not less than 4.

[0030] Claim 4: The ratio of the height of the percolation filler to the diameter of the cross-sectional area of ​​the percolation container is preferably 2 (inclusive) to 4 (inclusive).

[0031] V. Implementation Plan:

[0032] The present invention does not change the percolation principle, but it has the following advantages which significantly affect the percolation performance:

[0033] The applicant provides the following examples to further illustrate the advantages of the percolation method of the present invention. It should be understood that these examples are intended solely to facilitate understanding of the present invention and should not be construed as limiting the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the claims.

[0034] The percolation tank of the present invention can be cylindrical, conical or a mixed geometry of the two.

[0035] The present invention relates to a method for extracting active ingredients from traditional Chinese medicine (plants), the extraction method comprising the following steps:

[0036] a. Crush the Chinese medicinal materials (plants) into powder (granules), mix them, place them in a container and add a solvent to fully wet the material;

[0037] b. Add the fully moistened medicinal materials (plants) to the percolation container and fill it with filler, especially controlling the filler height (select appropriate equipment);

[0038] c. Percolation

[0039] d. Collect the percolation liquid and determine the content of the target component.

[0040] In addition, the "Key Points of the Percolation Method" in Part IV of the 2020 Edition of the Chinese Pharmacopoeia is as follows:

[0041] (1) Depending on the nature of the medicinal material, a cylindrical or conical percolator can be selected.

[0042] (2) The medicinal pieces must be properly crushed, evenly moistened with the specified solvent, sealed and placed for a certain period of time, and then placed in the percolator.

[0043] (3) The medicinal pieces should be placed evenly and with consistent tightness when put into the percolator. When adding the solvent, the air in the gaps between the medicinal pieces should be removed as much as possible. The solvent should be higher than the surface of the medicine. After soaking for an appropriate time, percolation should be carried out.

[0044] (4) The percolation rate should comply with the requirements of each type.

[0045] (5) Collect 85% of the initial filtered liquid and store it in another container. After low-temperature concentration, combine the subsequent filtered liquid with the initial filtered liquid, adjust it to the specified amount, let it stand, and take the supernatant for packaging.

[0046] Example 1

[0047] The present invention's embodiment, "Rhubarb Fluid Extract," involves percolating rhubarb, followed by concentration and preparation, and analyzing the percolation liquid for emodin and chrysophanol. The materials, devices, methods, steps, and other parameters and definitions mentioned in this invention have the meanings commonly understood by those skilled in the art and can be referenced to the definitions in Parts I and IV of the 2020 edition of the Chinese Pharmacopoeia.

[0048] According to the quality standard for "rhubarb" in Part I of the 2020 edition of the Chinese Pharmacopoeia, this product is the dried roots and rhizomes of Rheum palmatum L., Rheum tanguticum Maxim. ex Balf., or Rheum officinale Baill. (all Polygonaceae). It should be harvested in late autumn when the stems and leaves wither or before budding in the following spring. The rootlets should be removed, the bark scraped off, and the petals or segments cut into pieces. The dried rhubarb should be strung into strings or dried directly.

[0049] [Content Determination] Total anthraquinone was determined by high performance liquid chromatography (General Rule 0512).

[0050] The chromatographic conditions and system suitability test used octadecylsilane bonded silica gel as the filler, methanol-0.1% phosphoric acid solution (85:15) as the mobile phase, and a detection wavelength of 254 nm. The theoretical plate number calculated based on the rhein peak should be no less than 3000.

[0051] Preparation of reference solution: Accurately weigh appropriate amounts of aloe-emodin reference, rhein reference, emodin reference, chrysophanol reference, and physcion reference, and add methanol to prepare solutions containing 80 μg each of aloe-emodin, rhein, emodin, and chrysophanol, and 40 μg of physcion methyl ether per 1 ml; accurately measure 2 ml of each of the above reference solution and mix well to obtain (16 μg each of aloe-emodin, rhein, emodin, and chrysophanol, and 8 μg of physcion methyl ether per 1 ml).

[0052] Preparation of the test solution: Take approximately 0.15 g of the product powder (passed through a No. 4 sieve), accurately weigh it, place it in a stoppered conical flask, accurately add 25 ml of methanol, weigh it, heat and reflux for 1 hour, let it cool, weigh it again, make up the lost weight with methanol, shake it well, and filter it. Accurately measure 5 ml of the filtrate, place it in a flask, evaporate the solvent, add 10 ml of 8% hydrochloric acid solution, sonicate for 2 minutes, add 10 ml of chloroform, heat and reflux for 1 hour, let it cool, place it in a separatory funnel, wash the container with a small amount of chloroform, and add it to the separatory funnel. Separate the chloroform layer, extract the acid solution with chloroform three times, 10 ml each time, combine the chloroform solutions, recover the solvent under reduced pressure to dryness, dissolve the residue in methanol, transfer it to a 10 ml volumetric flask, add methanol to the mark, shake it well, filter it, and take the filtrate.

[0053] Determination method: Accurately aspirate 10μl of reference solution and test solution respectively, inject into liquid chromatograph, and determine.

[0054] Calculated on the basis of dry product, this product contains not less than 1.5% of total anthraquinones as the total amount of aloe-emodin (C15H10O5), rhein (C15H8O6), emodin (C15H10O5), chrysophanol (C15H10O4) and physophanol methyl ether (C16H12O5).

[0055] Among them, [Content Determination] Total anthraquinones: calculated on the basis of dry product, the total anthraquinones contained in this product shall not be less than 1.5% in terms of the total amount of aloe-emodin (C15H10O5), rhein (C15H8O6), emodin (C15H10O5), chrysophanol (C15H10O4) and physophanol methyl ether (C16H12O5).

[0056] According to the quality standard for rhubarb fluid extract in the 2020 edition of the Chinese Pharmacopoeia, this product is a fluid extract made from processed rhubarb. [Preparation method] Take 1000g of rhubarb (coarsest powder) and use 60% ethanol as a solvent. After soaking for 24 hours, slowly percolate at a rate of 1 to 3 ml per minute. Collect 850ml of the initial percolate and store it in a separate container. Continue percolation until the percolate color becomes light. Collect the subsequent percolate and concentrate it to a thick paste. Add the initial percolate, mix well, dilute to 1000ml with 60% ethanol, let it stand, wait for clarification, and filter to obtain the product. [Content Assay] The total amount of emodin (C15H10O5) and chrysophanol (C15H10O4) contained in this product shall not be less than 0.45%.

[0057] According to the above [Preparation Method], except for the ratio of the filler height in the percolation tank to the cross-sectional diameter of the percolation tank, the other process parameters are the same. Samples are prepared and the content is determined. The [Content Determination] results in the statutory standard are shown in the table below.

[0058] Table 1. Results of material content obtained at different height-to-diameter ratios

[0059]

[0060]

[0061] * 1. The content of emodin in the original medicinal material (plant) of rhubarb is 0.242%, and chrysophanol is 2.114%.

[0062] 2. The test results show that the larger the ratio, the higher the extraction rate. After a series of tests, for the preparation of rhubarb fluid extract, the upper limit of the ratio is about 4.5, and the extraction rate tends to be flat thereafter.

[0063] Example 2

[0064] To illustrate the importance of the ratio of packing height to percolation vessel cross-sectional diameter in this invention, the contents of various components in the percolate extracted in the aforementioned experiments are also presented. Increasing this ratio significantly improves percolation extraction efficiency for most components.

[0065] Table 2. Content of characteristic components in sample 1

[0066]

[0067]

[0068] Table 3. Content of characteristic components in sample 2

[0069]

[0070] Table 4. Content of each characteristic component in sample 3

[0071]

[0072]

[0073] Example 3

[0074] To illustrate the importance of the ratio of packing height to percolation vessel cross-sectional diameter in the present invention, another set of experimental data is presented. The percolation material was red peony root, with a paeoniflorin content of 2.0%. All other process conditions were the same.

[0075] Table 5. Results of substance contents obtained at different height-to-diameter ratios

[0076] Serial number Ratio of packing height to container cross-sectional diameter Paeoniflorin content (μg / ml) Sample 1 4 230 Sample 2 0.8 94.85

Claims

1. During percolation, adjust the "filling height" of the processed material used for percolation of medicinal materials (plants) in the percolation container.

2. According to claim 1, the more detailed control is "the ratio of the packing height to the cross-sectional diameter of the percolation container". According to claim 1, the percolation container is a cylindrical, conical or mixed geometric body of the two forms, and its diameter (radius) refers to the diameter (radius) of its main use part, that is, the middle part (barrel body).

3. The ratio of the height of the percolation packing to the cross-sectional diameter of the percolation container shall not be less than 2. The ratio according to claim 2, wherein the ratio of the packing height to the percolation vessel radius is not less than 4.

4. The ratio of the height of the percolation packing to the diameter of the cross-sectional area of ​​the percolation container is preferably 2 (inclusive) to 4 (inclusive).

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