Method for extracting polygonatum polysaccharide from polygonatum cyrtonema

Abstract

The invention provides a method for extracting polygonatum polysaccharide from polygonatum cyrtonema. The method comprises the following steps: S1, pretreating raw materials; s2, polysaccharide extraction; s3, separation and purification; and S4, concentrating and drying. According to the method for extracting the polygonatum polysaccharide from the polygonatum cyrtonema, the extraction rate of the polygonatum polysaccharide is increased through the application of an ultrasonic-assisted extraction method and a microwave-assisted extraction method, compared with a traditional hot water extraction method, polysaccharide components can be more sufficiently obtained from the polygonatum cyrtonema, and the polygonatum polysaccharide can be extracted from the polygonatum cyrtonema through separation and purification steps such as Sevag method deproteinization and dialysis. Protein, small molecular impurities and the like are effectively removed, the obtained polygonatum sibiricum polysaccharide is high in purity and meets the strict requirements of medicines, foods and other high-end fields for purity, the concentration and drying mode has small influence on polysaccharide activity, the biological activity of the polygonatum sibiricum polysaccharide is reserved to the maximum extent, energy consumption is reduced, and in the concentration and drying process, the concentration and drying efficiency is improved. And the energy-saving and efficient production process is realized through vacuum concentration of the rotary evaporator and reasonable drying parameter setting.

Description

Technical Field

[0001] This invention relates to the field of extracting Polygonatum polysaccharides, and more particularly to a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum. Background Art

[0002] Polygonatum multiflorum is a perennial herb belonging to the genus Polygonatum in the family Liliaceae, possessing both medicinal and economic value. Its rhizome is thick and segmented, resembling a chicken's head or a string of beads, and is rich in Polygonatum polysaccharides, steroidal saponins, amino acids, and other components. In traditional medicine, Polygonatum multiflorum is considered a superior tonic, possessing the effects of replenishing qi and yin, strengthening the spleen and moistening the lungs, and tonifying the kidneys and replenishing essence. It is often used to improve symptoms such as fatigue, dry mouth, poor appetite, and dry cough due to lung deficiency. Modern research shows that its Polygonatum polysaccharides have antioxidant, immune-regulating, and blood sugar-lowering effects, showing great potential in pharmaceutical research and development and health food development. Polygonatum multiflorum prefers shady and damp environments, mostly growing under forests, in thickets, or on shady hillsides. With increasing market demand, artificial cultivation techniques are constantly developing, making it a distinctive traditional Chinese medicine.

[0003] Polygonatum multiflorum, a plant with rich medicinal value, contains polysaccharides that exhibit significant effects in anti-oxidation, immune regulation, and blood sugar reduction.

[0004] However, traditional extraction methods are insufficient in terms of extraction rate, purity, and activity retention, making it difficult to meet the growing market demand and scientific research requirements. Conventional hot water extraction is time-consuming and has low polysaccharide dissolution efficiency; simple enzymatic hydrolysis can destroy cell walls to a certain extent, but it is costly and complicated to operate.

[0005] Therefore, it is necessary to provide a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum, which solves the problems of long time consumption and low polysaccharide dissolution efficiency of conventional hot water extraction method; and the high cost and complicated operation of simple enzymatic hydrolysis method, although it can destroy the cell wall to a certain extent.

[0007] To solve the above-mentioned technical problems, the present invention provides a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum, comprising the following steps:

[0008] S1: Raw material pretreatment: After harvesting Polygonatum multiflorum, impurities are removed and the raw materials are washed through a pretreatment device, cut into thin slices or small pieces, dried by hot air, and then crushed and sieved into fine powder.

[0009] S2: Polysaccharide extraction: Ultrasonic-assisted extraction method is used to mix Polygonatum odoratum fine powder with water in a certain proportion, and ultrasonic cavitation is used to accelerate the dissolution of Polygonatum odoratum polysaccharides;

[0010] S3: Separation and purification: After extraction, the protein is removed by centrifugation, followed by dialysis to remove small molecule impurities.

[0011] S4: Concentration and Drying: The purified solution is concentrated and then spray-dried and freeze-dried to obtain the Polygonatum polysaccharide product, which is soluble in water and ethanol.

[0012] Preferably, the method for extracting Polygonatum polysaccharides from Polygonatum multiflorum requires the use of a cleaning device, which further includes: a base; a support plate is fixedly installed in the middle of the top of the base, a cleaning cylinder is fixedly installed on one side of the surface of the support plate, an installation baffle is bolted to the front side of the outer surface of the cleaning cylinder, a rotating column is rotatably installed in the middle of the inside of the cleaning cylinder, a connecting plate is fixedly installed on the outer surface of the rotating column, a plurality of first cleaning brushes are fixedly installed at equal intervals on the outer surface of the connecting plate, and a plurality of second cleaning brushes are fixedly installed at equal intervals on the surface of the inner wall of the cleaning cylinder;

[0013] The mounting bracket is fixedly installed on the other side of the outer surface of the support plate. A lifting member is fixedly installed in the middle of the mounting bracket. A filter plate is fixedly connected to the output shaft end of the lifting member. The surface of the filter plate has multiple filter holes. A connecting groove is opened on one side of the outer surface of the cleaning cylinder. A discharge groove is opened at the bottom of the inner wall of the cleaning cylinder.

[0014] Preferably, a water tank is fixedly installed on the other side of the support plate, a pump body is provided on the top of the water tank, a drain pipe is fixedly connected to one side of the pump body, and a water inlet pipe is fixedly installed on the other side of the top of the water tank.

[0015] Preferably, a feeding box is fixedly installed on the top of the cleaning cylinder, and a cover is provided on the top of the outer surface of the feeding box.

[0016] Preferably, a collection box is provided on the other side of the top of the base.

[0017] Preferably, the base is provided with casters on all four sides of its bottom.

[0018] Preferably, one end of the drain pipe extends into the interior of the cleaning cylinder.

[0019] Preferably, a servo motor is installed inside the support plate, and the output shaft end of the servo motor is fixedly connected to the inside of the rotating column.

[0020] Preferably, the connecting groove and the feeding groove are interconnected.

[0021] Preferably, the filter plate is installed inside the feed trough via the connecting groove.

[0022] Compared with related technologies, the method for extracting Polygonatum polysaccharides from Polygonatum odoratum provided by the present invention has the following beneficial effects:

[0023] This invention provides a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum. The application of ultrasound-assisted and microwave-assisted extraction improves the extraction rate of Polygonatum polysaccharides. Compared with traditional hot water extraction, this method can more fully extract polysaccharide components from Polygonatum multiflorum. Through separation and purification steps such as Sevag deproteinization and dialysis, proteins and small molecule impurities are effectively removed, resulting in high-purity Polygonatum polysaccharides that meet the stringent purity requirements of high-end fields such as pharmaceuticals and food. The concentration and drying method has minimal impact on polysaccharide activity, maximizing the preservation of the bioactivity of Polygonatum polysaccharides and enabling them to better exert their antioxidant and immunomodulatory effects in applications. Ultrasound and microwave-assisted extraction significantly shorten the extraction time and reduce energy consumption. During the concentration and drying process, the rotary evaporator's reduced pressure concentration and reasonable drying parameter settings achieve an energy-efficient and high-performance production process. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the first embodiment of a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum provided by the present invention;

[0025] Figure 2 This is a schematic diagram of the second embodiment of a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum provided by the present invention;

[0026] Figure 3 for Figure 2 The enlarged schematic diagram at point A is shown below;

[0027] Figure 4 for Figure 2 The diagram shows the interior of the cleaning cylinder;

[0028] Figure 5 for Figure 4 The enlarged schematic diagram at point B is shown below;

[0029] Figure 6 for Figure 2 The diagram shows a side view of the base.

[0030] The following are the labels in the diagram: 1. Base, 2. Support plate, 3. Cleaning cylinder, 4. Discharge box, 5. Cover box, 6. Mounting baffle, 7. Water tank, 8. Mounting bracket, 9. Lifting component, 10. Connecting groove, 11. Filter plate, 12. Filter hole, 13. Discharge trough, 14. Rotating column, 15. Connecting plate, 16. First cleaning brush, 17. Second cleaning brush, 18. Drain pipe, 19. Collection box, 20. Moving wheel, 21. Water inlet pipe, 22. Pump body. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] First Embodiment

[0033] Please refer to Figure 1 ,in, Figure 1 This is a schematic diagram of the first embodiment of a method for extracting Polygonatum polysaccharides from Polygonatum odoratum provided by the present invention.

[0034] A method for extracting Polygonatum polysaccharides from Polygonatum multiflorum includes the following steps:

[0035] S1: Raw material pretreatment: After harvesting Polygonatum multiflorum, impurities are removed and the raw materials are washed through a pretreatment device, cut into thin slices or small pieces, dried by hot air, and then crushed and sieved into fine powder.

[0036] S2: Polysaccharide extraction: Ultrasonic-assisted extraction method is used to mix Polygonatum odoratum fine powder with water in a certain proportion, and ultrasonic cavitation is used to accelerate the dissolution of Polygonatum odoratum polysaccharides;

[0037] S3: Separation and purification: After extraction, the protein is removed by centrifugation, followed by dialysis to remove small molecule impurities.

[0038] S4: Concentration and Drying: The purified solution is concentrated and then spray-dried and freeze-dried to obtain the Polygonatum polysaccharide product, which is soluble in water and ethanol.

[0039] In the process of polysaccharide extraction, ultrasonic-assisted extraction or microwave-assisted extraction can be used.

[0040] During the concentration and drying process, the purified solution is concentrated and can be spray-dried or freeze-dried to obtain the Polygonatum polysaccharide product, which is soluble in water or ethanol.

[0041] The working principle of the method for extracting Polygonatum polysaccharides from Polygonatum odoratum provided by this invention is as follows:

[0042] During the process, mature Polygonatum plants are first selected for harvesting. Immediately after harvesting, the Polygonatum plants are placed in a special pretreatment device. This device is equipped with a vibrating screening component and a high-pressure water spray assembly. The vibrating screening removes impurities such as soil and sand adhering to the surface of the Polygonatum plants. Then, the high-pressure water spray assembly is used to rinse the surface of the Polygonatum plants to ensure that the surface of the Polygonatum plants is clean and free of impurities.

[0043] The washed Polygonatum odoratum is cut into thin slices with a thickness of 3-5mm or small pieces with a side length of 5-8mm using an automatic slicing and dicing device, according to the subsequent drying and extraction requirements, in order to facilitate subsequent drying and dissolution of active ingredients.

[0044] Two methods can be used: hot air drying or vacuum freeze drying. If hot air drying is used, place the cut Polygonatum odoratum in a hot air drying device, set the temperature to 50-60℃, the air speed to 2-3m / s, and the drying time to 6-8 hours until the moisture content of Polygonatum odoratum decreases.

[0045] If vacuum freeze drying is chosen, first freeze Polygonatum multiflorum to -40℃ to -30℃ and keep it at that temperature for 2-3 hours to completely freeze the moisture. Then, sublime drying is carried out under a vacuum of 10-30 Pa for 10-12 hours.

[0046] The dried Polygonatum odoratum was put into a pulverizer and pulverized. After pulverization, it was screened through a 100-120 mesh sieve to obtain a uniform fine powder of Polygonatum odoratum, which was prepared for the subsequent extraction steps.

[0047] Mix the fine powder of Polygonatum cyrtonema with the extraction medium (water or ethanol) at a ratio of 1:15-1:20 (g / mL) in an ultrasonic extraction device. Turn on the ultrasonic device, set the ultrasonic frequency to 40-60kHz, the power to 200-300W, the extraction temperature to 40-50℃, and the extraction time to 30-40 minutes. During the ultrasonic process, the instantaneous high pressure generated by ultrasonic cavitation causes the Polygonatum cyrtonema cells to rupture, accelerating the dissolution of Polygonatum cyrtonema polysaccharides into the extraction medium. When the ultrasonic cavitation bubbles close instantaneously, they can generate pressures of up to several thousand atmospheres around them, causing the cell walls and intracellular structures to rupture and the polysaccharides to be released rapidly.

[0048] When the fine powder of Polygonatum odoratum is mixed with the extraction medium (water or ethanol) in a ratio of 1:12-1:18 (g / mL) in a microwave extraction device, the microwave power is set to 300-400W, the microwave radiation time is 10-15 minutes, and the temperature is maintained at 50-60℃. Under the action of microwave high-frequency vibration, the molecules in the fine powder of Polygonatum odoratum and the extraction medium vibrate and rub rapidly, generating heat, which promotes the rapid dissolution of Polygonatum odoratum polysaccharides in cells. Under the action of microwave, the molecules can vibrate billions of times per second, which greatly increases the collision frequency between molecules and accelerates the dissolution of polysaccharides.

[0049] After extraction, the mixture is centrifuged at 3000-4000 rpm for 10-15 minutes to obtain a supernatant containing Polygonatum polysaccharides. The Sevag method is then used to remove proteins from the supernatant: a mixture of chloroform and n-butanol (4-5:1 volume ratio) is added, shaken for 20-30 minutes, and then centrifuged at 3000-3500 rpm for 10-15 minutes to remove the intermediate protein layer and the lower organic layer. This process is repeated 3-4 times until the UV absorbance of the supernatant at 280 nm remains essentially unchanged. The deproteinized supernatant is then placed in a dialysis bag (with a molecular weight cutoff of 3000-5000 Da) and dialyzed in deionized water for 24-36 hours to remove small molecule impurities.

[0050] The dialysis solution was concentrated using a rotary evaporator at a temperature of 50-60℃ and a vacuum of 0.06-0.08MPa to reduce the solution volume to 1 / 5-1 / 3 of its original volume. The final product, Polygonatum polysaccharide, was then obtained by spray drying or freeze drying.

[0051] If spray drying is used, the inlet air temperature is set to 160-180℃ and the outlet air temperature is 80-90℃; if freeze drying is selected, the concentrate is first frozen to -50℃ to -40℃ and maintained for 3-4 hours, and then dried under a vacuum of 5-10Pa for 12-15 hours to finally obtain a high-purity Polygonatum polysaccharide product, which is soluble in water or ethanol and other media.

[0052] Compared with related technologies, the method for extracting Polygonatum polysaccharides from Polygonatum odoratum provided by the present invention has the following beneficial effects:

[0053] This invention provides a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum. The application of ultrasound-assisted and microwave-assisted extraction improves the extraction rate of Polygonatum polysaccharides. Compared with traditional hot water extraction, this method can more fully extract polysaccharide components from Polygonatum multiflorum. Through separation and purification steps such as Sevag deproteinization and dialysis, proteins and small molecule impurities are effectively removed, resulting in high-purity Polygonatum polysaccharides that meet the stringent purity requirements of high-end fields such as pharmaceuticals and food. The concentration and drying method has minimal impact on polysaccharide activity, maximizing the preservation of the bioactivity of Polygonatum polysaccharides and enabling them to better exert their antioxidant and immunomodulatory effects in applications. Ultrasound and microwave-assisted extraction significantly shorten the extraction time and reduce energy consumption. During the concentration and drying process, the rotary evaporator's reduced pressure concentration and reasonable drying parameter settings achieve an energy-efficient and high-performance production process.

[0054] Second Embodiment

[0055] Please refer to Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 Based on the method for extracting Polygonatum polysaccharides from Polygonatum multiflorum provided in the first embodiment of this application, the second embodiment of this application proposes another method for extracting Polygonatum polysaccharides from Polygonatum multiflorum. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0056] Specifically, the second embodiment of this application provides a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum, which differs in that the method requires the use of a cleaning device. The cleaning device further includes: a base 1; a support plate 2 is fixedly installed in the middle of the top of the base 1; a cleaning cylinder 3 is fixedly installed on one side of the surface of the support plate 2; a mounting baffle 6 is bolted to the front side of the outer surface of the cleaning cylinder 3; a rotating column 14 is rotatably installed in the middle of the interior of the cleaning cylinder 3; a connecting plate 15 is fixedly installed on the outer surface of the rotating column 14; a plurality of first cleaning brushes 16 are fixedly installed at equal intervals on the outer surface of the connecting plate 15; and a plurality of second cleaning brushes 17 are fixedly installed at equal intervals on the surface of the inner wall of the cleaning cylinder 3.

[0057] Mounting bracket 8 is fixedly mounted on the other side of the outer surface of the support plate 2. A lifting member 9 is fixedly mounted in the middle of the mounting bracket 8. A filter plate 11 is fixedly connected to the end of the output shaft of the lifting member 9. A plurality of filter holes 12 are opened on the surface of the filter plate 11. A connecting groove 10 is opened on one side of the outer surface of the cleaning cylinder 3. A discharge groove 13 is opened at the bottom of the inner wall of the cleaning cylinder 3.

[0058] A water tank 7 is fixedly installed on the other side of the support plate 2. A pump body 22 is provided on the top of the water tank 7. A drain pipe 18 is fixedly connected to one side of the pump body 22. An inlet pipe 21 is fixedly installed on the other side of the top of the water tank 7.

[0059] A feeding box 4 is fixedly installed on the top of the cleaning cylinder 3, and a cover box 5 is provided on the top of the outer surface of the feeding box 4.

[0060] A collection box 19 is provided on the other side of the top of the base 1.

[0061] The base 1 is equipped with casters 20 on all four sides of its bottom.

[0062] One end of the drain pipe 18 extends into the interior of the cleaning cylinder 3.

[0063] A servo motor is installed inside the support plate 2, and the output shaft end of the servo motor is fixedly connected to the inside of the rotating column 14.

[0064] The connecting groove 10 and the feeding groove 13 are interconnected.

[0065] The filter plate 11 is installed inside the feed trough 13 through the connecting groove 10.

[0066] The filter plate 11 and the connecting groove 10 are compatible. The filter plate 11 is inserted into the inside of the feeding groove 13 through the connecting groove 10, blocking the feeding groove 13.

[0067] The lifting component 9 adopts a hydraulic cylinder structure.

[0068] The motor output shaft inside the support plate 2 is connected to the rotating column 14 via a coupling.

[0069] The first cleaning brush 16 and the second cleaning brush 17 are bristle brushes, each composed of multiple bristles. They are made of soft material and are easy to use for cleaning Polygonatum odoratum.

[0070] The working principle of the method for extracting Polygonatum polysaccharides from Polygonatum odoratum provided by this invention is as follows:

[0071] During operation, firstly, place Polygonatum sibiricum into the cleaning cylinder 3 through the feeding box 4, and add cleaning water into the water tank 7.

[0072] The servo motor output shaft rotates, driving the rotating column 14 to rotate. The rotating column 14 rotates, driving the first cleaning brush 16 to rotate and wash the Solomon's seal. While the Solomon's seal is being driven, it is also being rubbed and cleaned by the second cleaning brush 17. The drain pipe 18 sprays water from the water tank 7 into the cleaning cylinder 3 through the pump body 22 to rinse the Solomon's seal, causing the mud and sewage on the surface of the Solomon's seal to fall downwards and fall from the filter hole 12 into the collection box 19.

[0073] After cleaning, remove collection box 19 and replace it with a new one. The new collection box 19 is used to collect the cleaned Polygonatum.

[0074] The lifting component 9 moves its output shaft, pulling the filter plate 11 out of the feeding trough 13 and causing the Polygonatum to fall from the feeding trough 13 into the collection box 19 and be collected.

[0075] Compared with related technologies, the method for extracting Polygonatum polysaccharides from Polygonatum odoratum provided by the present invention has the following beneficial effects:

[0076] This invention provides a method for extracting Polygonatum polysaccharides from Polygonatum multiflorum. A rotating column 14 drives a first cleaning brush 16 to rotate and wash the Polygonatum inside a cleaning cylinder 3. While the Polygonatum is agitated, the first cleaning brush 16 and the second cleaning brush 17 wash it. Water is discharged through a dehumidification pipe 18 for rinsing. Mud and sand on the surface of the Polygonatum are washed away by the water and discharged through a filter hole 12 for collection. The washed Polygonatum is then collected. This device has a simple structure, is highly practical, and provides a convenient and simple cleaning method, improving the cleaning effect of Polygonatum and reducing the labor intensity of operators.

[0077] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for extracting Polygonatum polysaccharides from Polygonatum multiflorum, characterized in that, Includes the following steps: S1: Raw material pretreatment: After harvesting Polygonatum multiflorum, impurities are removed and the raw materials are washed through a pretreatment device, cut into thin slices or small pieces, dried by hot air, and then crushed and sieved into fine powder. S2: Polysaccharide extraction: Ultrasonic-assisted extraction method is used to mix Polygonatum odoratum fine powder with water in a certain proportion, and ultrasonic cavitation is used to accelerate the dissolution of Polygonatum odoratum polysaccharides; S3: Separation and purification: After extraction, the protein is removed by centrifugation, followed by dialysis to remove small molecule impurities. S4: Concentration and Drying: The purified solution is concentrated and then spray-dried and freeze-dried to obtain the Polygonatum polysaccharide product, which is soluble in water and ethanol.

2. The method for extracting Polygonatum polysaccharides from Polygonatum multiflorum according to claim 1, characterized in that, The method for extracting Polygonatum polysaccharides from Polygonatum multiflorum requires the use of a cleaning device, which further includes: a base; a support plate fixedly installed in the middle of the top of the base; a cleaning cylinder fixedly installed on one side of the surface of the support plate; a mounting baffle is bolted to the front side of the outer surface of the cleaning cylinder; a rotating column is rotatably installed in the middle of the inside of the cleaning cylinder; a connecting plate is fixedly installed on the outer surface of the rotating column; a plurality of first cleaning brushes are fixedly installed at equal intervals on the outer surface of the connecting plate; and a plurality of second cleaning brushes are fixedly installed at equal intervals on the surface of the inner wall of the cleaning cylinder. The mounting bracket is fixedly installed on the other side of the outer surface of the support plate. A lifting member is fixedly installed in the middle of the mounting bracket. A filter plate is fixedly connected to the output shaft end of the lifting member. The surface of the filter plate has multiple filter holes. A connecting groove is opened on one side of the outer surface of the cleaning cylinder. A discharge groove is opened at the bottom of the inner wall of the cleaning cylinder.

3. The method for extracting Polygonatum polysaccharides from Polygonatum multiflorum according to claim 2, characterized in that, A water tank is fixedly installed on the other side of the support plate. A pump body is installed on the top of the water tank. A drain pipe is fixedly connected to one side of the pump body, and an inlet pipe is fixedly installed on the other side of the top of the water tank.

4. The method for extracting Polygonatum polysaccharides from Polygonatum multiflorum according to claim 2, characterized in that, A feeding box is fixedly installed on the top of the cleaning cylinder, and a cover is provided on the top of the outer surface of the feeding box.

5. A method for extracting Polygonatum polysaccharides from Polygonatum odoratum according to claim 2, characterized in that, A collection box is provided on the other side of the top of the base.

6. A method for extracting Polygonatum polysaccharides from Polygonatum odoratum according to claim 2, characterized in that, The base is equipped with casters on all four sides of its bottom.

7. A method for extracting Polygonatum polysaccharides from Polygonatum multiflorum according to claim 3, characterized in that, One end of the drain pipe extends into the interior of the cleaning cylinder.

8. A method for extracting Polygonatum polysaccharides from Polygonatum odoratum according to claim 2, characterized in that, A servo motor is installed inside the support plate, and the output shaft end of the servo motor is fixedly connected to the inside of the rotating column.

9. A method for extracting Polygonatum polysaccharides from Polygonatum odoratum according to claim 2, characterized in that, The connecting trough and the feeding trough are interconnected.

10. A method for extracting Polygonatum polysaccharides from Polygonatum odoratum according to claim 2, characterized in that, The filter plate is installed inside the feed trough through the connecting groove.

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