CN111012893A

CN111012893A - Ginger extract with anti-inflammatory activity and preparation method thereof

Info

Publication number: CN111012893A
Application number: CN202010017118.0A
Authority: CN
Inventors: 郭孝萱; 钱永忠; 邱静; 宿冬雪
Original assignee: Institute of Agricultural Quality Standards and Testing Technology for Agro Products of CAAS
Current assignee: Institute of Agricultural Quality Standards and Testing Technology for Agro Products of CAAS
Priority date: 2020-01-08
Filing date: 2020-01-08
Publication date: 2020-04-17

Abstract

A ginger extract with anti-inflammatory activity and a preparation method thereof belong to the field of biological medicine. The method comprises the following steps: dried ginger powder heated to be completely dried at a temperature of 60 ℃ to 90 ℃ is provided. Extracting the dried ginger powder by using ethanol or ethanol with the volume content of more than 50% as an extracting agent at the material-liquid ratio of 1: 1-1: 40 and under the condition of normal temperature-90 ℃ to obtain an extracting solution. The rhizoma Zingiberis recens extract obtained by the method has high activity, and is suitable for anti-inflammatory application.

Description

Ginger extract with anti-inflammatory activity and preparation method thereof

Technical Field

The application relates to the field of biological pharmacy, in particular to a ginger extract with anti-inflammatory activity and a preparation method thereof.

Background

The anti-inflammatory activity of ginger as a plant used as both medicine and food is widely reported and applied. The anti-inflammatory activity of the ginger extract on an animal level and a cell level is researched by a plurality of scholars, and the result proves that the ginger extract can effectively reduce the secretion of inflammatory factors, the expression of inflammatory genes and the risk of inflammation-related diseases. Therefore, ginger or an extract thereof is taken as a main component in many anti-inflammatory related food formulas and functional foods at present. However, the extract obtained by the existing ginger extraction method has low activity, thereby limiting the application of the extract in the aspect of anti-inflammation.

Disclosure of Invention

The application provides a ginger extract and a preparation method thereof, which aim to solve the problem that the extract obtained by the existing ginger extraction method is not high in activity.

The application is realized as follows:

in a first aspect, examples of the present application provide a method of preparing a ginger extract.

The method comprises the following steps:

providing dry ginger powder obtained by heating fresh ginger to be dry at a temperature of 60-90 ℃, wherein the particle size of the dry ginger powder is below the aperture of a mesh of a 30-mesh screen.

Extracting the dried ginger powder for 3 to 5 times with the material-liquid ratio of 1:1g/mL to 1:40g/mL for 30 to 60 minutes each time by using ethanol or ethanol with the volume content of more than 50% as an extracting agent, and combining the extracting agents after three times of extraction to obtain an extracting solution. Removing ethanol from the extractive solution by distillation under reduced pressure, and freeze drying to obtain solid.

In a second aspect, embodiments of the present application provide a ginger extract obtained by the aforementioned method for preparing a ginger extract.

In the implementation process, the method provided by the embodiment of the application completely dries the ginger at the temperature of 60-90 ℃, so that the activity of the active substances in the ginger is improved, and then the active substances are extracted. The obtained ginger extract has anti-inflammatory effect.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the prior art of the present application, the drawings used in the description of the embodiments or the prior art will be briefly described below.

FIG. 1 is the effect of ginger extract on NO secretion by RAW264.7 cells;

FIG. 2 is the effect of ginger extract on IL-6 secretion from RAW264.7 cells;

FIG. 3 is the effect of ginger extract on the expression of iNOS mRNA in RAW264.7 cells;

FIG. 4 effect of ginger extract on IL-6mRNA expression in RAW264.7 cells.

Detailed Description

Embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present application and should not be construed as limiting the scope of the present application. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The following is a detailed description of the preparation method of ginger extract according to the embodiments of the present application:

currently, 6-gingerol is known as the main active ingredient in ginger extract, and the structure of the active ingredient is shown in the following formula 1.

Specifically, the inventors found that 6-gingerol is unstable when heated, and that the active ingredient present as gingerol has β -hydroxy ketone group structure in the molecular structure of 6-gingerol, and that heat can remove one molecule of water to form the corresponding shogaols, as shown in formula 2.

Therefore, the inventor believes that if the main active ingredient (6-gingerol) in ginger extract can be converted into a more active ingredient by a certain technique, the ginger extract will have the effect of being used with half the effort in anti-inflammatory applications.

As previously mentioned, 6-gingerol is thermally unstable and is susceptible to structural changes by heat, thereby altering biological activity. However, it is necessary to carefully examine how to heat it, and particularly, the heating mode in the extraction process needs to be properly selected. The following describes a method for preparing ginger extract in the examples of the present application.

In an example, the method of preparing ginger extract of the present application comprises: dried ginger powder is provided in which fresh ginger is heated to be dried at a temperature of 60 ℃ to 90 ℃ (the water content of the dried ginger powder may be limited to 0 to 5 wt%). Extracting the dried ginger powder for 3 to 5 times with the material-liquid ratio of 1:1g/mL to 1:40g/mL for 30 to 60 minutes each time by using ethanol or ethanol with the volume content of more than 50% as an extracting agent, and combining the extracting agents after three times of extraction to obtain an extracting solution. Removing ethanol from the extractive solution by vacuum distillation, and freeze drying to obtain solid.

The ginger extract having improved biological activity can be obtained by the above-mentioned operations. As mentioned above, the inventors believe that the particular choice of heating temperature and heating regime during the preparation of ginger extract will help to obtain an extract with stable and high bioactivity. Thus, heating prior to extraction of the ginger material is an option in the present application being an example. For example, dried ginger powder is obtained by pulverizing fresh ginger after heat-drying at 60 ℃ to 90 ℃ (e.g., 63 ℃, 74 ℃, 88 ℃, etc.).

For convenience of extraction, the ginger is further processed into ginger powder or ginger paste before drying. For example, after cleaning fresh ginger and treating scars, the ginger is cut into pieces by hand or broken by a beater. In addition, the dried ginger powder can be further crushed based on the requirement of convenient early-stage drying and subsequent leaching. In the example, the particle size of the further pulverized dried ginger powder is not larger than the mesh aperture of a 30-mesh sieve. Thus, the ginger is crushed in a relatively larger size and then dried, and then subjected to a relatively smaller size crushing operation. Thus, ginger is dried by heating in a relatively large size while maintaining the activity of the active material, and then extracted by refining particles in order to improve extraction efficiency.

Through the above operation, ginger is prepared in an easily extractable state and contains a high content of bioactive substance/target substance (6-shogaol). For a specific extraction method, extraction at normal temperature or extraction by heating may be employed. The extractant in the extraction process is selected from ethanol or its water solution.

For example, in the step of extracting the dried ginger powder, the temperature of the extract is from room temperature to 90 ℃ (e.g., 42 ℃, 46 ℃, 52 ℃, 58 ℃, 63 ℃, 69 ℃, 75 ℃ or 88 ℃). Under heating conditions, the method for extracting the dried ginger powder can be selected to include a reflux method or an ultrasonic method, and the power of the ultrasonic wave can be selected to be between 90W and 300W. Generally, the method of heat extraction is applicable to thermally stable substances. However, as previously mentioned, it is contemplated that 6-shogaol may be obtained by thermal conversion of 6-shogaol, and thus, the heating method will generally facilitate extraction of 6-shogaol.

Among them, the reflux method is, for example, a method of extracting a target substance using volatile ethanol or an aqueous solution thereof as an organic solvent. In the process, volatile components are condensed and repeatedly flow back to the leacher to extract medicinal materials. Repeating the steps until the reflux extraction of the effective components is complete. The method is suitable for extracting heat stable medicinal materials.

The ultrasonic extraction method benefits from the ultrasonic cavitation effect, and the sound impact flow and the impact wave generated by ultrasonic cavitation can cause local violent turbulence of a liquid system and high-speed collision of solid particles, so that a mass transfer boundary layer is thinned, and the mass transfer rate is increased.

The effect of ultrasonic extraction depends on the intensity and frequency of the extract, and is related to the tissue structure of the medicinal material, and the secondary effects of ultrasonic waves, such as mechanical vibration, emulsification, diffusion, crushing, chemical effect, etc., can also accelerate the diffusion release of the extract.

In order to obtain a high yield, avoid losses and at the same time increase the conversion, multiple extractions are carried out with a suitable increase in the time of each extraction. In the example, the dried ginger powder is extracted 3 to 5 times. The time of each extraction is selected to be 30 to 60 minutes (34 minutes, 37 minutes, 42 minutes, 46 minutes, 55 minutes or 59 minutes), and the extractants after three extractions are combined to obtain an extracting solution.

The extract may be filtered through a filter membrane to remove impurities. The extractant, which may comprise ethanol, or a mixture of ethanol and water, is then removed by appropriate steps. Wherein ethanol is evaporated by distillation under reduced pressure to remove ethanol, and water is removed by freeze drying. In an example, ethanol is removed from the extract, followed by removal of water.

The temperature in the process of removing ethanol in the extracting solution by reduced pressure distillation is 40-50 ℃, the pressure is 100-150Pa, and the time is 1-3 hours.

Freeze-drying is, for example, a drying method in which the extract is removed of ethanol, frozen to a temperature below the freezing point of water to convert the water into ice, and then the ice is removed by converting the ice into vapor under a relatively high vacuum. The conditions of the freeze-drying may be selectively adjusted according to the circumstances, for example, the degree of vacuum is limited to less than 10Pa, and the drying time is limited to, for example, 48 hours.

The ginger extract, which exists as a solid body and can be studied and used as a solution by dissolving in an organic solvent, can be obtained based on the implementation of the above-described scheme. And the extract showed anti-inflammatory effect under study.

The preparation of ginger extract of the present application is further described in detail with reference to the following examples.

Example 1

1. The preparation method of the extract comprises the following steps:

cutting fresh ginger into ginger powder, drying in an oven at 60 ℃, crushing the dried ginger, sieving with a 40-mesh sieve, adding 70% ethanol water solution according to the material-liquid ratio of 1:20, performing ultrasonic extraction for 30 minutes at normal temperature, repeatedly extracting for 3 times, distilling the obtained filtrate under reduced pressure to remove ethanol, and freeze-drying to obtain the ginger extract, wherein the ginger extract is recorded as 60G (the 6-shogaol content is 421.41 +/-62.91 mg/kg, and the recovery rate is 92.5 +/-12.35%).

Example 2

1. The preparation method of the extract comprises the following steps:

cutting fresh ginger into ginger powder, drying in an oven at 90 ℃, crushing the dried ginger, sieving by a 40-mesh sieve, adding 70% ethanol water solution according to the material-liquid ratio of 1:20, performing ultrasonic extraction for 30 minutes at normal temperature, repeatedly extracting for 3 times, distilling the obtained filtrate under reduced pressure to remove ethanol, and freeze-drying to obtain the ginger extract, wherein the ginger extract is recorded as 90G (the 6-shogaol content is 999.50 +/-173.64 mg/kg, and the recovery rate is 92.5 +/-12.35%).

Comparative example 1

1. The preparation method of the extract comprises the following steps:

cutting fresh rhizoma Zingiberis recens into powder, pulverizing, sieving with 40 mesh sieve, adding 70% ethanol water solution at a ratio of 1:20, performing ultrasonic extraction at room temperature for 30 min, repeatedly extracting for 3 times, distilling the filtrate under reduced pressure to remove ethanol, and freeze drying to obtain rhizoma Zingiberis recens extract (FG (6-shogaol content 11.67 + -1.08 mg/kg, recovery rate 92.5 + -12.35%).

Test example 1

In vitro anti-inflammatory assays.

(1) And (4) detecting the content of NO in the cell culture supernatant.

Mouse macrophage cells in logarithmic growth phase Raw264.7 were plated in 12-well plates and cultured for 24h, cells were incubated for 24h with 0.1. mu.g/mLLPS and 50mg/mL extract, cell supernatants were collected and quantified for NO production by the NO standard curve using Greiss reagent. The results are shown in FIG. 1, where 60G and 90G are better able to inhibit cellular NO production than FG.

(2) And (4) detecting the content of IL-6 in the cell culture supernatant.

Mouse macrophage cells in logarithmic growth phase Raw264.7 were plated in 12-well plates and cultured for 24h, cells were incubated for 24h with 0.1. mu.g/mLLPS and 50mg/mL extract, and cell supernatants were collected and assayed for IL-6 levels using ELISA kits. The results are shown in FIG. 2, where 60G and 90G are better able to inhibit the production of the cytokine IL-6 than FG.

(3) Inflammation-associated gene expression in cells.

Mouse macrophage Raw264.7 in logarithmic growth phase is plated in a 12-well plate and cultured for 24h, 0.1 mu g/mLLPS and 50mg/mL extract are added to incubate cells for 24h, RNA is collected and extracted from the cells, the RNA is reversely transcribed into cDNA, and the iNOS and IL-6mRNA expression level of the cells is detected by real-time quantitative PCR. The results are shown in FIGS. 3 and 4, where 60G and 90G are better able to inhibit cellular inflammation-associated mRNA expression than FG.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method of preparing a ginger extract, comprising:

providing dry ginger powder obtained by heating fresh ginger to be completely dried at a temperature of 60-90 ℃, wherein the particle size of the dry ginger powder is below the aperture of a mesh of a 30-mesh screen;

extracting the dried ginger powder for 3 to 5 times under the condition of a material-liquid ratio of 1:1g/mL to 1:40g/mL by using ethanol or ethanol with the volume content of more than 50% as an extracting agent, wherein the extracting time is 30 to 60 minutes each time, and combining the extracting agents after three times of extraction to obtain an extracting solution;

removing ethanol from the extractive solution by distillation under reduced pressure, and freeze drying to obtain solid.

2. The method of claim 1, wherein the dried ginger powder is obtained by pulverizing fresh ginger after drying the ginger under heating at a temperature of 60 ℃ to 90 ℃.

3. The method of preparing a ginger extract according to claim 1, wherein the fresh ginger is further processed into bruised ginger or mashed ginger prior to drying.

4. The method of claim 1, wherein the dried ginger powder has a particle size of less than or equal to a mesh aperture of a 30 mesh screen.

5. The method of claim 1, wherein the step of extracting the dried ginger powder comprises extracting the dried ginger powder at a temperature of room temperature to 90 ℃.

6. The method of claim 5, wherein the extraction of the dried ginger powder is performed by a reflux method or an ultrasonic method.

7. The method as claimed in claim 1, wherein the temperature of the process of removing ethanol from the extractive solution by distillation under reduced pressure is 40-50 ℃, the pressure is 100-150Pa, and the time is 1-3 hours.

8. A ginger extract obtained by the method for producing a ginger extract according to any one of claims 1 to 7.