Preparation process of calcined oyster shell
Calcined oyster shells were prepared by freeze-drying and two-stage microwave frequency conversion calcination, which solved the problems of high energy consumption and long calcination time, improved the efficacy of calcined oyster shells, especially the therapeutic effect on peptic gastric ulcers, and demonstrated antioxidant capacity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHUHAI WANBAO TRADITIONAL CHINESE MEDICINE CO LTD
- Filing Date
- 2025-09-03
- Publication Date
- 2026-05-29
AI Technical Summary
Existing methods for preparing calcined oyster shells are energy-intensive, time-consuming, and have a significant impact on efficacy. There is a lack of simple and effective calcination methods.
Calcined oyster shells were prepared by freeze-drying and two-stage microwave frequency conversion calcination. The freeze-drying process formed a porous structure, and then microwave frequency conversion calcination was used to heat the inside and outside of the oyster shells simultaneously, which shortened the calcination time and maintained the efficacy.
The resulting calcined oyster shell is brittle and easy to crush, with a high calcium carbonate content and a high dissolution rate of active ingredients. It has significant anti-ulcer and antioxidant effects, and is especially effective in treating peptic gastric ulcers.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of traditional Chinese medicine processing technology, specifically to a preparation process for calcined oyster shell and its application. Background Technology
[0002] Oysters are the shells of the Pacific oyster (Ostrea gigas Thunberg), the Dalian Bay oyster (Ostrea salinae whanensis Crosse), or the rivularis Gould, all belonging to the family Ostreidae. Calcined oyster shell is a traditional Chinese medicine made by calcining oyster shells. Its main functions include regulating the liver and kidneys, stopping night sweats and diarrhea, improving dizziness, tinnitus, abnormal sweating, seminal emission, and excessive stomach acid, and also eliminating lumps in the body.
[0003] Currently, calcined oyster shells are generally prepared using the open calcination method, which involves taking oyster shells, breaking them into small pieces, placing them in a suitable container, and calcining them until they are brittle or reddish-brown. However, there are no clear regulations regarding the calcination temperature, time, particle size, and layering thickness. Patent document CN101507735A discloses an optimal oyster processing technology, the process steps of which are: (1) crushing the oyster shells and placing them in a crucible; (2) selecting toxicity and efficacy as indicators to screen the calcination temperature; (3) selecting four factors for consideration: calcination temperature, calcination time, crushing particle size, and layering thickness, each with three levels, and using an orthogonal array for calcination. The final optimized oyster processing technology is to crush the oyster shells into particles with a particle size of 5 cm. 3 Small pieces of calcined oyster shell were spread to a thickness of 4 cm and calcined at 550℃ for 1.5 hours. The resulting calcined oyster shell had a relative hardness of 30.67, a relative density of 3.0, a porosity of 0.86, and a CaCO3 content of 94.77%. It showed good repeatability and met the pharmacopoeia standards.
[0004] Patent document CN118845841A discloses a process for preparing calcined oyster shells. The process includes the following steps: S1, lotus seeds are steamed, pulped with water, and filtered to obtain lotus seed paste. Then, broken rice flour, river sand, and carrageenan are added to the lotus seed paste and mixed to obtain a pretreatment auxiliary material. This pretreatment auxiliary material is then applied to oyster shells; S2, the oyster shells with the pretreatment auxiliary material are preheated at 200–240℃ for 30–60 minutes. After preheating, they are soaked in salt water for 20–40 minutes while still hot. After soaking, the pretreatment auxiliary material is washed away with salt water, and then rinsed with clean water to obtain pretreated oyster shells; S3, the pretreated oyster shells are dried and then calcined at 340–380℃ for 80–100 minutes to obtain calcined oyster shells. This process has the advantages of reducing energy consumption in the calcination process while ensuring the calcination effect.
[0005] However, current methods for calcining oyster shells involve high temperatures, long calcination times, and significant energy consumption. Furthermore, different calcination methods have a substantial impact on the efficacy of calcined oyster shells. Therefore, researching and developing a simple, reproducible calcination method that can significantly improve the efficacy of calcined oyster shells remains a pressing problem to be solved. Summary of the Invention
[0006] The purpose of this invention is to provide a preparation process for calcined oyster shells and its applications. The calcined oyster shell preparation process provided by this invention involves freeze-drying oyster shells after they have absorbed water, causing the water inside the shells to crystallize and sublimate, forming a porous and loose structure. Then, a two-stage microwave frequency conversion calcination process is used to simultaneously heat and calcine the inside and outside of the oyster shells, resulting in brittle calcined oyster shells with significant medicinal properties. This preparation process not only shortens the calcination time and lowers the calcination temperature, but also effectively prevents calcium carbonate from converting to calcium oxide, thus preserving the medicinal efficacy. The calcined oyster shells prepared using this process not only have the advantages of being brittle and easily crushed, with a high calcium carbonate content and a high dissolution rate of active ingredients, but also have a strong anti-ulcer effect, especially showing significant therapeutic effects on peptic gastric ulcers.
[0007] To achieve the above objectives, the technical solution of the present invention is as follows:
[0008] This invention provides a process for preparing calcined oyster shells, comprising the following steps:
[0009] Step S1: Wash the oyster shells to remove mud and attached substances, and then soak the washed oyster shells in a gelatin solution for 30-40 minutes. After that, freeze-dry them to obtain pre-treated oyster shells.
[0010] Step S2: Cool the pretreated oyster shells obtained in step S1, wash them clean with water, drain them, microwave them, cool them, pulverize them, and pass them through a 70-100 mesh to obtain the final product.
[0011] Furthermore, in step S1, the ratio of the cleaned oyster shells to the gelatin aqueous solution is 1g:10-12mL.
[0012] Furthermore, in step S1, the gelatin aqueous solution is a gelatin aqueous solution with a weight percentage concentration of 2-6 wt%.
[0013] Furthermore, the freeze-drying conditions in step S1 are: freezing at -5 to -20°C for 10 to 16 hours.
[0014] Further, the microwave calcination treatment step in step S2 is as follows: the pre-treated oyster shells after cleaning are heated in a microwave environment at a frequency of 550-650MHz for 40-60 minutes, and then heated in a microwave environment at a frequency of 850-950MHz for 20-30 minutes. The microwave power is 700-800W and the microwave heating temperature is 320-340℃.
[0015] In addition, the present invention provides the application of calcined oyster prepared by the aforementioned calcined oyster preparation process in the preparation of drugs for treating peptic gastric ulcers.
[0016] Furthermore, the present invention also provides the application of calcined oyster prepared by the aforementioned calcined oyster preparation process in the preparation of drugs or health products with antioxidant properties.
[0017] Furthermore, the present invention also provides a composition containing calcined oyster shell, comprising the following components and their parts by weight:
[0018] 12-16 parts calcined oyster powder, 6-8 parts astragalus extract, 6-8 parts jujube extract, and 10-12 parts licorice extract.
[0019] Furthermore, the astragalus extract, jujube extract, and licorice extract are prepared by the following methods:
[0020] Weigh the medicinal materials, add distilled water, the ratio of the medicinal materials to the distilled water is 1g:(20-30)mL, sonicate at 50-80℃ for 40-60min, the power of the sonication is 125-145W, filter, concentrate, freeze dry to obtain the final product.
[0021] Furthermore, the present invention also provides a method for preparing the composition containing calcined oyster shell, comprising the following steps:
[0022] A. Take calcined oyster powder, add 10-12 times its weight of distilled water, decoct for 25-30 minutes, filter, and collect the filtrate; take the residue, add 8-10 times its weight of distilled water, decoct for 20-25 minutes, filter, and collect the filtrate; combine the filtrates, concentrate, and freeze-dry to obtain calcined oyster extract.
[0023] B. Mix the astragalus extract, jujube extract, and licorice extract with the calcined oyster extract obtained in step A until homogeneous.
[0024] The processing of oysters has a long history. Currently, the 2020 edition of the Chinese Pharmacopoeia specifies that calcined oysters should be "calcined until red-hot and brittle," without specifying the calcination temperature and time. The inventors have discovered that the processing method significantly impacts the efficacy of calcined oysters. To better preserve the efficacy of calcined oysters against peptic ulcers, the inventors have proposed for the first time a two-stage microwave frequency conversion calcination method. This invention provides a calcination method that simultaneously heats both the inside and outside of the oyster shell, resulting in uniform calcination temperature, shortening the calcination time, and improving the calcination quality.
[0025] Furthermore, through extensive experimentation, the inventors optimized a process to improve the efficacy of calcined oyster shells for treating peptic ulcers. Specifically, the process involves soaking cleaned oyster shells in a gelatin solution. The gelatin allows water to quickly diffuse across the oyster shell surface and penetrate and adsorb into the shell, saturating it with moisture. The water-saturated shells are then freeze-dried, causing the water adsorbed inside and on the surface to crystallize and sublimate. The original crystal locations form pores, effectively increasing the porous structure of the oyster shell and facilitating the dissolution of its active ingredients. Additionally, the freeze-dried oyster shells are then subjected to frequency-conversion microwave calcination, rapidly heating both the interior and surface simultaneously. The heating temperature is controlled at 320–340°C, and microwave calcination for 60–90 minutes achieves a thoroughly reddish-brown color and a crisp texture.
[0026] Furthermore, the inventors discovered through experiments that the calcined oyster shell prepared according to this invention has a significant therapeutic effect on hydrochloric acid-induced gastric ulcers. Simultaneously, the inventors also unexpectedly discovered that the calcined oyster shell also possesses good antioxidant effects and a strong scavenging effect on DPPH free radicals, which can effectively broaden the application range of calcined oyster shell and enhance its medicinal value.
[0027] In addition, the present invention provides a composition containing calcined oyster, which is composed of calcined oyster powder, astragalus extract, jujube extract and licorice extract. The components work synergistically to effectively enhance the anti-ulcer and antioxidant effects of calcined oyster.
[0028] In summary, compared with the prior art, the preparation process of calcined oyster shell provided by the present invention has the following advantages:
[0029] (1) The preparation process of calcined oyster provided by the present invention has the advantages of convenient operation, short calcination time and low energy consumption. At the same time, the calcined oyster obtained has the advantages of high effective component dissolution rate and high calcium carbonate content.
[0030] (2) The calcined oyster prepared by this invention not only has a significant therapeutic effect on hydrochloric acid-type gastric ulcers, but also has strong antioxidant activity, which can effectively improve the medicinal value of calcined oyster. Detailed Implementation
[0031] The present invention will be further described below through specific embodiments, but this is not intended to limit the invention. Those skilled in the art can make various modifications or improvements based on the basic idea of the invention, but as long as they do not depart from the basic idea of the invention, they are all within the scope of the invention. The raw materials and components involved in the present invention can all be obtained commercially available or through conventional techniques in the art.
[0032] Example 1: A preparation process for calcined oyster shell
[0033] Step S1: Wash the oyster shells to remove mud and attached substances, and then soak the washed oyster shells in a gelatin aqueous solution for 30 minutes. The gelatin aqueous solution is a gelatin aqueous solution with a weight percentage concentration of 6 wt%. Then freeze it at -10℃ for 12 hours to obtain pretreated oyster shells.
[0034] Step S2: Cool the pretreated oyster shells obtained in step S1, wash them clean with water, drain them, and then perform microwave calcination treatment. The microwave calcination treatment steps are as follows: place the cleaned pretreated oyster shells under microwave frequency of 550MHz for 60 minutes, and then place them under microwave frequency of 950MHz for 20 minutes. The microwave power is 800W and the microwave heating temperature is 330℃. After cooling, pulverize them and pass them through a 70-mesh sieve to obtain the final product.
[0035] Example 2: A preparation process for calcined oyster shell
[0036] Step S1: Wash the oyster shells to remove mud and attached substances, and then soak the washed oyster shells in a gelatin aqueous solution for 35 minutes. The gelatin aqueous solution is a gelatin aqueous solution with a weight percentage concentration of 5 wt%. Then freeze it at -10℃ for 14 hours to obtain pretreated oyster shells.
[0037] Step S2: Cool the pretreated oyster shells obtained in step S1, clean them, drain them, and then perform microwave calcination treatment. The microwave calcination treatment steps are as follows: place the cleaned pretreated oyster shells under microwave frequency of 565MHz for 50 minutes, and then place them under microwave frequency of 865MHz for 25 minutes. The microwave power is 800W and the microwave heating temperature is 330℃. After cooling, pulverize them and pass them through an 80-mesh sieve to obtain the final product.
[0038] Example 3: A preparation process for calcined oyster shell
[0039] Step S1: Wash the oyster shells to remove mud and attached substances, and then soak the washed oyster shells in a gelatin aqueous solution for 40 minutes. The gelatin aqueous solution is a gelatin aqueous solution with a weight percentage concentration of 3 wt%. Then freeze it at -10℃ for 15 hours to obtain pretreated oyster shells.
[0040] Step S2: Cool the pretreated oyster shells obtained in step S1, clean them, drain them, and then perform microwave calcination treatment. The microwave calcination treatment steps are as follows: place the cleaned pretreated oyster shells under microwave frequency of 650MHz for 40 minutes, and then place them under microwave frequency of 850MHz for 30 minutes. The microwave power is 700W and the microwave heating temperature is 330℃. After cooling, pulverize them and pass them through 100 mesh to obtain the final product.
[0041] Comparative Example 1: A preparation process for calcined oyster shell
[0042] The difference from Example 2 is that in step S1, the oyster shells are washed to remove mud and attached substances, resulting in cleaned oyster shells; the remaining steps are similar to those in Example 2.
[0043] Comparative Example 2: A preparation process for calcined oyster shell
[0044] The difference from Example 2 is that in step S1, the oyster shells are washed to remove mud and attached substances, and the washed oyster shells are soaked in distilled water for 35 minutes, and then frozen at -10°C for 14 hours to obtain pretreated oyster shells; the remaining steps are similar to those in Example 2.
[0045] Comparative Example 3: A preparation process for calcined oyster shell
[0046] The difference from Example 2 is that in step S2, the pretreated oyster shells obtained in step S1 are cooled, cleaned, drained, and then heated for 75 minutes at a microwave frequency of 565MHz, a microwave power of 800W, and a microwave heating temperature of 330℃. After cooling, they are pulverized and passed through an 80-mesh sieve. The remaining steps are similar to those in Example 2.
[0047] Comparative Example 4: A preparation process for calcined oyster shell
[0048] The difference from Example 2 is that in step S2, the pretreated oyster shells obtained in step S1 are cooled, cleaned, drained, and then heated for 75 minutes at a microwave frequency of 865MHz, a microwave power of 800W, and a microwave heating temperature of 330℃. After cooling, they are pulverized and passed through an 80-mesh sieve. The remaining steps are similar to those in Example 2.
[0049] Example 4: A composition containing calcined oyster shell
[0050] The composition containing calcined oyster shell consists of the following components and their parts by weight:
[0051] The mixture contained 12 parts calcined oyster powder, 6 parts Astragalus extract, 6 parts Jujube extract, and 10 parts Licorice extract. The calcined oyster powder was the calcined oyster powder prepared in Example 2.
[0052] Preparation method:
[0053] A. Take calcined oyster powder, add 12 times its weight of distilled water, decoct for 30 minutes, filter, and collect the filtrate; take the residue, add 8 times its weight of distilled water, decoct for 20 minutes, filter, and collect the filtrate; combine the filtrates, concentrate, and freeze-dry to obtain calcined oyster extract;
[0054] B. Take dried Astragalus root, wash it clean, crush it to obtain Astragalus powder, add distilled water, the ratio of Astragalus powder to distilled water is 1g:30mL, sonicate at 55℃ for 40min, the power of sonication is 135W, filter, concentrate, freeze dry to obtain Astragalus extract.
[0055] C. Take jujube fruits, remove the pits, wash them clean, crush them to obtain jujube powder, add distilled water, the ratio of jujube powder to distilled water is 1g:20mL, sonicate at 65℃ for 50min, the sonication power is 145W, filter, concentrate, freeze dry to obtain jujube extract.
[0056] D. Take dried licorice root, wash it clean, crush it to obtain licorice powder, add distilled water, the ratio of licorice powder to distilled water is 1g:25mL, sonicate at 50℃ for 60min, the power of sonication is 125W, filter, concentrate, freeze dry to obtain licorice extract.
[0057] E. Mix the calcined oyster extract obtained in step A with the astragalus extract obtained in step B, the jujube extract obtained in step C, and the licorice extract obtained in step D until homogeneous to obtain the final product.
[0058] Example 5: A composition containing calcined oyster shell
[0059] The composition containing calcined oyster shell consists of the following components and their parts by weight:
[0060] The mixture contained 16 parts calcined oyster powder, 8 parts astragalus extract, 8 parts jujube extract, and 12 parts licorice extract. The calcined oyster powder was the calcined oyster powder prepared in Example 2.
[0061] Preparation method:
[0062] A. Take calcined oyster powder, add 12 times its weight of distilled water, decoct for 30 minutes, filter, and collect the filtrate; take the residue, add 8 times its weight of distilled water, decoct for 20 minutes, filter, and collect the filtrate; combine the filtrates, concentrate, and freeze-dry to obtain calcined oyster extract;
[0063] B. Take dried Astragalus root, wash it clean, crush it to obtain Astragalus powder, add distilled water, the ratio of Astragalus powder to distilled water is 1g:30mL, sonicate at 55℃ for 40min, the power of sonication is 135W, filter, concentrate, freeze dry to obtain Astragalus extract.
[0064] C. Take jujube fruits, remove the pits, wash them clean, crush them to obtain jujube powder, add distilled water, the ratio of jujube powder to distilled water is 1g:20mL, sonicate at 65℃ for 50min, the sonication power is 145W, filter, concentrate, freeze dry to obtain jujube extract.
[0065] D. Take dried licorice root, wash it clean, crush it to obtain licorice powder, add distilled water, the ratio of licorice powder to distilled water is 1g:25mL, sonicate at 50℃ for 60min, the power of sonication is 125W, filter, concentrate, freeze dry to obtain licorice extract.
[0066] E. Mix the calcined oyster extract obtained in step A with the astragalus extract obtained in step B, the jujube extract obtained in step C, and the licorice extract obtained in step D until homogeneous to obtain the final product.
[0067] Comparative Example 5: A composition containing calcined oyster shell
[0068] The composition containing calcined oyster shell consists of the following components and their parts by weight:
[0069] The mixture contained 12 parts calcined oyster powder, 6 parts jujube extract, and 10 parts licorice extract, wherein the calcined oyster was the calcined oyster obtained in Example 2.
[0070] The preparation method is similar to that in Example 4.
[0071] Comparative Example 6: A composition containing calcined oyster shell
[0072] The composition containing calcined oyster shell consists of the following components and their parts by weight:
[0073] The mixture contained 12 parts calcined oyster powder, 6 parts Astragalus extract, and 10 parts Glycyrrhiza extract, wherein the calcined oyster was the calcined oyster obtained in Example 2.
[0074] The preparation method is similar to that in Example 4.
[0075] Experimental Example 1: Property Testing of Calcined Oyster Shell
[0076] 1. Test sample:
[0077] Calcined oyster shells prepared in Examples 1, 2, 3, 1, 2, 3 and 4.
[0078] 2. Test methods:
[0079] The calcium carbonate content and the Fe and Zn content in the decoction of calcined oyster shells prepared in Examples 1, 2, 3, 1, 2, 3 and 4 were determined.
[0080] 2.1 Determination of calcium carbonate content:
[0081] Take 0.15g of calcined oyster sample and place it in an Erlenmeyer flask. Add 10mL of dilute hydrochloric acid and heat to dissolve. Add 20mL of water and 1 drop of methyl red indicator. Add 10% potassium hydroxide solution until the solution turns yellow. Continue adding 10mL of solution, then add a small amount of calcein indicator. Titrate with 0.05mol / L disodium ethylenediaminetetraacetate solution until the yellow-green fluorescence disappears and the solution turns orange. Each 1mL of 0.05mol / L disodium ethylenediaminetetraacetate solution is equivalent to 5.004mg of calcium carbonate.
[0082] 2.2 Determination of Fe and Zn content in the decoction:
[0083] Take 0.3g of calcined oyster sample, accurately weigh it, add 5mL of concentrated nitric acid to a beaker and heat to 60-80℃ to completely dissolve it, evaporate to dryness, transfer to a 100mL volumetric flask, dilute to the mark with distilled water, and determine the Fe and Zn content using a plasma atomic emission spectrometer.
[0084] 3. Test Results:
[0085] The experimental results are shown in Table 1.
[0086] Table 1 Content of calcium carbonate, Fe and Zn
[0087] Group Calcium carbonate content (%) Fe content (μg / g) Zn content (μg / g) Example 1 98.6 34.52 3.84 Example 2 98.8 36.28 3.95 Example 3 98.3 34.68 3.82 Comparative Example 1 98.2 28.79 2.93 Comparative Example 2 98.3 30.61 3.04 Comparative Example 3 97.9 23.84 2.07 Comparative Example 4 96.5 26.65 2.50
[0088] As shown in Table 1, the calcined oyster shell prepared by this invention has a high calcium carbonate content and high Fe and Zn content in the decoction, which can effectively preserve the medicinal efficacy of calcined oyster shell.
[0089] Experimental Example 2: Effects of Calcined Oyster Shell on Hydrochloric Acid-Induced Gastric Ulcers
[0090] 1. Test sample:
[0091] Calcined oyster obtained in Example 2, and compositions containing calcined oyster obtained in Examples 4, 5 and 6.
[0092] 2. Test methods:
[0093] Wistar rats (brand: Liaoning Changsheng Biotechnology, product number: CS-002), male, 6-7 weeks old, weighing 190-200g. They were fasted for 24 hours before the experiment, but water was allowed. After weighing, they were randomly divided into a model group and an experimental group, with 5 rats in each group. The experimental group animals were administered the drugs from Examples 2, 4, 5, and 6 by gavage. Specifically, the concentration of the calcined oyster shell decoction prepared in Example 2 was 5g / mL, and the concentration of the compositions from Examples 4, 5, and 6 was 3g / mL with distilled water, 1mL per rat. The model group received the same volume of distilled water. One hour later, each rat was administered 1.5mL of 0.6mol / L HCl (hydrochloric acid) by gavage. One hour after that, the rats were decapitated, the cardia was ligated, 10mL of 1% formaldehyde was injected through the pylorus, the pylorus was ligated again, the stomach was removed, and the stomach was fixed in a 1% formaldehyde solution for 10 minutes. The stomach was cut open along the greater curvature to observe the degree of gastric mucosal damage and calculate the ulcer index and inhibition rate. The scoring criteria were as follows: 1 point was scored for each millimeter of mucosal lesion longer than 1 mm, 2 points were scored for each millimeter wider than 1 mm, and 0.5 points were scored for each lesion less than 1 mm in both length and width. The scores were added together to obtain the ulcer index, and the inhibition rate was then calculated based on the ulcer index.
[0094] 3. Test Results:
[0095] The experimental results are shown in Table 2.
[0096] Table 2. Effects of calcined oyster shell on HCl-type gastric ulcers.
[0097] Group <![CDATA[Ulcer index (mm 2 )]]> Inhibition rate (%) Model group 175.9±98.7 - Example 2 81.8±100.5 53.5 Example 4 2.5±8.3 98.6 Comparative Example 5 47.8±28.5 72.8 Comparative Example 6 61.0±36.2 65.3
[0098] As shown in Table 2, the calcined oyster shell prepared in this invention exhibits an inhibition rate of over 53% against HCl-type gastric ulcers, demonstrating a strong therapeutic effect. Furthermore, the composition containing calcined oyster shell provided by this invention shows a significant therapeutic effect against HCl-type gastric ulcers, while the therapeutic effects of Comparative Example 5 (lacking Astragalus extract) and Comparative Example 6 (lacking Jujube extract) on HCl-type gastric ulcers are reduced. This indicates that the interaction between the components of Astragalus extract and Jujube extract and the calcined oyster shell extract and licorice extract can enhance the therapeutic effect against HCl-type gastric ulcers.
[0099] Experimental Example 3: Antioxidant Effect of Calcined Oyster Shell
[0100] 1. Test sample:
[0101] Calcined oyster obtained in Example 2, and compositions containing calcined oyster obtained in Examples 4, 5 and 6.
[0102] 2. Test methods:
[0103] The antioxidant activity of the calcined oyster shell prepared in Example 2, and the compositions containing calcined oyster shell prepared in Examples 4, 5, and 6 were analyzed by determining the antioxidant activity using DPPH assay.
[0104] The calcined oyster extract obtained in Example 2 was diluted to 1 mg / mL. The compositions containing calcined oyster obtained in Examples 4, 5, and 6 were diluted to 1 mg / mL with distilled water to obtain diluted solutions. 1 mL of each diluted solution was added to 1 mL of 0.1 mmol / L DPPH-anhydrous ethanol solution, mixed, and reacted at room temperature in the dark for 30 min to obtain sample solutions. The absorbance at 517 nm was measured (denoted as A1). The absorbance of the blank group was measured using anhydrous ethanol instead of the sample solution (denoted as A0). The control group was measured using anhydrous ethanol instead of the sample solution.
[0105] The absorbance of the DPPH-anhydrous ethanol solution was determined by reaction (denoted as A2). The DPPH free radical scavenging rate was calculated using the following formula:
[0106]
[0107] 3. Test Results:
[0108] The experimental results are shown in Table 3.
[0109] Table 3 Antioxidant effects of calcined oyster shell
[0110] Group DPPH free radical scavenging rate (%) Example 2 40.63 Example 4 86.15 Comparative Example 5 61.82 Comparative Example 6 53.38
[0111] As shown in Table 3, the calcined oyster shell prepared in this invention has good antioxidant activity. Combining the calcined oyster shell with Astragalus membranaceus extract, jujube extract, and licorice extract can enhance its antioxidant activity and effectively improve the medicinal value of the calcined oyster shell.
[0112] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.
Claims
1. A composition containing calcined oyster shell, characterized in that, It consists of the following components and their parts by weight: Calcined oyster powder 12-16 parts, Astragalus extract 6-8 parts, Jujube extract 6-8 parts and Licorice extract 10-12 parts; The preparation process of the calcined oyster powder is as follows: Step S1: Wash the oyster shells to remove mud and attached substances, and then soak the washed oyster shells in a gelatin solution for 30-40 minutes. After that, freeze-dry them to obtain pre-treated oyster shells. Step S2: Cool the pretreated oyster shells obtained in step S1, wash them with water, drain them, microwave them, cool them, pulverize them, and pass them through a 70-100 mesh to obtain the final product. In step S1, the ratio of the cleaned oyster shells to the gelatin aqueous solution is 1 g: 10~12 mL. In step S1, the gelatin aqueous solution is a gelatin aqueous solution with a weight percentage concentration of 2~6 wt%. The freeze-drying conditions in step S1 are: freezing at -5 to -20 ℃ for 10 to 16 hours; The microwave calcination process in step S2 is as follows: the pre-treated oyster shells after cleaning are heated in a microwave environment at a frequency of 550-650 MHz for 40-60 minutes, and then heated in a microwave environment at a frequency of 850-950 MHz for 20-30 minutes. The microwave power is 700-800 W and the microwave heating temperature is 320-340 ℃.
2. The composition containing calcined oyster shell as described in claim 1, characterized in that, The Astragalus extract, Jujube extract, and Licorice extract were prepared by the following methods: Weigh the medicinal material, add distilled water, the ratio of the medicinal material to the distilled water is 1 g: (20~30) mL, sonicate at 50~80 ℃ for 40~60 min, the power of the sonication is 125~145 W, filter, concentrate, freeze dry to obtain the product.
3. The method for preparing the composition containing calcined oyster shell as described in claim 1, characterized in that, Includes the following steps: A. Take calcined oyster powder, add 10-12 times its weight of distilled water, decoct for 25-30 minutes, filter, and collect the filtrate; take the residue, add 8-10 times its weight of distilled water, decoct for 20-25 minutes, filter, and collect the filtrate; combine the filtrates, concentrate, freeze dry, and obtain calcined oyster extract. B. Mix the astragalus extract, jujube extract, and licorice extract with the calcined oyster extract obtained in step A until homogeneous.