A method for preparing a highly soluble, clear and transparent rosmarinic acid

Abstract

The application discloses a preparation method of high-solubility clear and transparent rosmarinic acid. The method comprises the following steps: subjecting dry rosemary leaves to water vapor distillation and ethanol distillation to obtain an extract; subjecting the extract to pressure reduction solidification, washing and filtration in sequence to obtain filtrate A; adding the filtrate A into acid liquor, and subjecting the mixture to precipitation, filtration, extraction and concentration to obtain a precursor; and subjecting the precursor to purification by acidified diatomite, and then drying to obtain the final product. The three-phase purification technology is used to remove macromolecular impurities and dark pigments in the dry rosemary leaves, and meanwhile, the effective components in the plant are completely reserved. Further, the diatomite is used for adsorption and purification treatment, which can not only effectively remove small molecular impurities and complex pigment in the rosmarinic acid, but also reduce the loss of the rosmarinic acid, so that the clear and transparent rosmarinic acid is obtained, and the yield of the product is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to a preparation method of rosemary extract, in particular to a preparation method of high-solubility clear and transparent rosmarinic acid, and belongs to the technical field of plant extraction. BACKGROUND

[0002] Rosmarinic acid is a water-soluble natural phenolic acid compound isolated from Rosmarinus officinalis of Labiatae, which is widely distributed in various plants of Labiatae, Boraginaceae, Cucurbitaceae, Tiliaceae and Umbelliferae, especially in Labiatae and Boraginaceae. Rosmarinic acid is a natural antioxidant with strong antioxidant activity, which is stronger than vitamin E, caffeic acid, chlorogenic acid and folic acid, and is helpful to prevent cell damage caused by free radicals, thereby reducing the risk of cancer and arteriosclerosis. Rosmarinic acid has strong anti-inflammatory activity, and also has antibacterial, antiviral and antitumor activities, and has the characteristics of inhibiting acute and chronic infection, resisting ultraviolet rays, inhibiting elastin degradation, etc., which has made rosmarinic acid become an additive of cosmetics. At present, rosmarinic acid has shown its important application value in the fields of medicine, food and cosmetics.

[0003] At present, the extraction process of rosmarinic acid is a hot spot in the food industry and the plant extraction industry, but there are few processes that can prepare high-content rosmarinic acid products. Most of them use macroporous resin adsorption separation method, which has the defects of complicated production steps, low production efficiency, high solvent residue of products, serious environmental pollution, etc. At the same time, some preparation methods also have the defect of low yield of rosmarinic acid product, which leads to low production benefit and is not conducive to the large-scale production and application of rosmarinic acid. By simple solvent extraction and displacement process, it is difficult to obtain rosmarinic acid product with light color and clearness after dissolving in water at a ratio of 1:100. SUMMARY

[0004] In view of the problems existing in the prior art, the present application provides a preparation method of high-solubility clear and transparent rosmarinic acid. Through the three-phase purification technology, the macromolecular impurities and dark pigments in the dried leaves of rosemary are removed while the effective components in the plant are completely retained. Further, through the adsorption purification treatment of diatomite, not only the small molecular impurities and complex pigments in rosmarinic acid can be effectively removed, but also the loss of rosmarinic acid can be reduced, so that clear and transparent rosmarinic acid can be obtained while the yield of the product is improved.

[0005] To achieve the above technical purposes, the application provides a preparation method of high-solubility clear transparent rosmarinic acid.

[0006] The initial extract of natural products is very complex, the extraction method adopted by the application is a three-phase extraction method, i.e. solid phase of precipitate-water phase-organic phase, which avoids the alcohol precipitation process of polysaccharide, achieves the separation of polysaccharide in a short time, and separates the protein and flavone in the water extract to a certain extent, improves the product purity, and then the solid impurity particles suspended in the liquid are intercepted on the surface and channel of the diatomite filter medium, so as to achieve the purpose of separation and purification.

[0007] As a preferred scheme, the water vapor distillation conditions are: temperature is 80-120℃, and time is 20-40min.

[0008] As a preferred scheme, the number of ethanol distillation is greater than or equal to 2.

[0009] As a preferred scheme, the mass ratio of ethanol to rosemary dry leaves is 5-8:1.

[0010] As a preferred scheme, the ethanol distillation conditions are: ethanol concentration is 75-90%, temperature is 60-70℃, and time is 40-60min.

[0011] As a preferred scheme, the acid liquid is one of phosphoric acid, hydrochloric acid, concentrated sulfuric acid, formic acid and citric acid, and the pH of the filtrate A is adjusted to 1-3.

[0012] As a preferred scheme, the extractant of the extraction process is an ester or an alcohol.

[0013] As a preferred scheme, the extraction conditions are: 0.3-1h of extraction under stirring at 20-45℃.

[0014] The three-phase extraction one-step method for extracting and purifying rosmarinic acid is provided, an organic phase is added to form a three-phase system, the pH is adjusted to 1-3 by using an acid, the extraction is completed by stirring, and then centrifugation is performed, so that the extraction, purification and impurity removal of rosmarinic acid are completed at one time, rosmarinic acid is extracted into the organic phase, and pigments, impurities and impurities are distributed into the lower aqueous phase; in the three-phase extraction one-step method process, the adsorption, desorption, water washing, alcohol washing and activation steps in the macroporous resin purification process of the original process can be saved, and the current process is effectively simplified. On the other hand, the formed aqueous phase is similar to a liquid filter membrane, and when rosmarinic acid is extracted into the organic phase, pigments, impurities and organic acids are left in the aqueous phase.

[0015] As a preferred scheme, the ester is one of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate and butyl acetate.

[0016] As a preferred scheme, the alcohol is one of n-butanol, isobutyl alcohol and isopropyl alcohol.

[0017] As a preferred scheme, the concentration process is that the obtained extract after extraction is added with water in an amount of 2-5 times the volume, and is evaporated under reduced pressure to a flowable paste, and the process is repeated 1-3 times, so that the rosmarinic acid is obtained.

[0018] As a preferred scheme, the conditions of the reduced pressure evaporation are that the temperature is 65-75 DEG C, the vacuum degree is -0.07-0.1 MPa, and the solvent is evaporated to a flowable paste.

[0019] As a preferred scheme, the diatomite purification process is that the precursor is mixed with the acidified diatomite mixture, the acidified diatomite mixture is washed with water, and the washing liquid is combined, so that the diatomite purification process is obtained.

[0020] As a preferred scheme, the preparation process of the acidified diatomite mixture is that the mixture of diatomite and silica gel is adjusted to a pH of 1.5-2.5 by using an acid adjusting agent, is placed for 0.5-1.5 h, and is sequentially filtered and dried, so that the acidified diatomite mixture is obtained. The mixture of diatomite and silica gel is adjusted to a pH of 1.5-2.5 by using an acid adjusting agent, is placed for 1 h after mixing, and is filtered and vacuum dried, so that the mixture is obtained.

[0021] As a preferred scheme, the filtering conditions of the acidified diatomite mixture are that the amount of the RA water liquid acidified diatomite mixture is 0.1-1%, and the vacuum degree is -0.04--0.07 MPa.

[0022] The acidified diatomite mixture has good micropore structure, adsorption performance and compression resistance, can not only obtain a good flow rate ratio of the filtered liquid, but also can filter out fine suspended solids, and ensures the clarity.

[0023] The application first adopts acid liquor such as sulfuric acid, nitric acid, hydrochloric acid as acid-adjusting agent to acidify the diatomite mixture to adjust PH to 1.5-2.5, and then is placed for 1h after mixing, and then is filtered and vacuum dried; after the diatomite acid immersion washing treatment, the impurity minerals in the coarse diatomite are removed and the pore is dredged. Through the electrokinetic attraction, when those diatomite internal pore small particles collide on the internal surface of the porous diatomite, are attracted by the opposite charges, and there is another kind of mutual attraction between the particles to form a chain group and adhere to the diatomite. In the net pressure filtration process of the suspension, the acid-activated diatomite filter aid is used as the filter medium, mainly to provide as many pores as possible for the filter cake, and the formed pore interval layer, so that the suspension passes through the small holes of the interval layer, and the solid impurity particles suspended in the liquid are intercepted on the surface and channel of the medium, so as to achieve the purpose of separation and purification.

[0024] As a preferred scheme, the drying method is spray drying, the solid content of the feed is 20-40%, and the drying temperature is 90-120℃.

[0025] The application also provides a detailed preparation process of high-solubility clear and transparent rosmarinic acid, comprising the following steps:

[0026] Step 1: after the rosemary dry leaves are subjected to steam distillation, 5-8 times the volume of the dry leaves in weight of an ethanol solution with a concentration of 75-90% is added, the extraction temperature is 60-70℃, the extraction time is 40-60min for each time, the filtrate is combined and concentrated into a solid under reduced pressure, then 2-3 times the mass of water of the dry leaves is added and stirred, filtered, and the filtrate is collected;

[0027] Step 2: an acid solution is added to the filtrate, the PH is adjusted to 1.0-3.0, and the precipitate is separated out after standing for 0.3-1h; the solution is filtered to separate the precipitate and obtain the filtrate; an organic solvent is added to the filtrate for extraction, and the solution is separated into layers after standing, the water phase is discharged, and the extraction solution is concentrated under reduced pressure until there is substantially no solvent, then 2-5 times the volume of water of the solvent addition amount is added in 1-3 times, and the residual solvent is further concentrated under reduced pressure to obtain a treatment solution;

[0028] Step 3: the treatment solution is subjected to diatomite compound adsorption purification treatment, a small amount of water (1 / 10-1 / 20 of the filtrate) is used to wash the diatomite once, and then the filtrate is combined to obtain a mixed solution for spray;

[0029] Step 4: the mixed solution is subjected to spray drying after the solid content is adjusted to 20-40% and the temperature is set to 90-120℃, and then a rosmarinic acid product with a content of 50-60% and a clear color after water dissolution is obtained.

[0030] Compared with the prior art, the application has the beneficial technical effects as follows:

[0031] 1) The preparation method provided by the present application can completely retain the effective components in the plant by removing the macromolecular impurities and dark pigments in rosemary dry leaves through a three-phase purification technology, and further, through the adsorption purification treatment of diatomite, not only the small molecular impurities and complex pigment in rosemary acid can be effectively removed, but also the loss of rosemary acid can be reduced, so that the clear and transparent rosemary acid can be obtained while the yield of the product is improved.

[0032] 2) In the technical solution provided by the present application, the extraction method is simple and reliable, the production steps are simple, the production efficiency is high, the environment is not easy to be polluted, the solvent can be recycled and reused, the diatomite can be recycled and reused, the cost is controllable, the water-soluble rosemary acid product with light color and clarity can be obtained, the yield of rosemary acid can be significantly improved, and the industrialized production and application of rosemary acid are facilitated. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The high performance liquid chromatogram of the rosemary acid product provided for example 1 of the present application;

[0034] Figure 2 The high performance liquid chromatogram of the rosemary acid product provided for example 2 of the present application;

[0035] Figure 3 The high performance liquid chromatogram of the rosemary acid product provided for example 3 of the present application;

[0036] Figure 4 The physical map of the rosemary acid product obtained from example 1-3 and comparative example 1 of the present application;

[0037] Figure 5 The phenomenon diagram of the 50-60% rosemary acid product prepared in example 1 of the present application after being dissolved in water in a ratio of 1:100;

[0038] Figure 6 The phenomenon diagram of the 50-60% rosemary acid product prepared in example 2 of the present application after being dissolved in water in a ratio of 1:100;

[0039] Figure 7 The phenomenon diagram of the 50-60% rosemary acid product prepared in example 3 of the present application after being dissolved in water in a ratio of 1:100;

[0040] Figure 8 The phenomenon diagram of the 50-60% rosemary acid product prepared in comparative example 2 of the present application after being dissolved in water in a ratio of 1:100. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with specific examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0042] Example 1

[0043] Take 3000g rosemary dry leaves, after steam distillation, add 8 times the volume of dry leaves, 80% ethanol solution, extract twice at 65℃, each time for 50min, combine the filtrate and concentrate under reduced pressure to form a solid, then add 3 times the mass of dry leaves of water, stir and wash, filter, collect the filtrate; add 5% phosphoric acid solution to the filtrate, adjust the PH to 2.5; let stand for 30min to precipitate the analyte, then filter the solution, separate the precipitate, add 2 times the volume of ethyl acetate to the filtrate, extract, let stand to separate the layers, release the water phase, and concentrate the extract under reduced pressure until there is essentially no solvent, then add 3 times the volume of water to the solvent in 2 portions, continue to concentrate under reduced pressure to remove the residual solvent, to obtain the treated liquid. The treated liquid is purified by adsorption with 0.5% acid-activated diatomite, then wash the diatomite with a small amount of water (1 / 10 of the filtrate) and combine it with the filtrate to form a uniform mixture; adjust the solid content of the mixture to 30%, and set the temperature to 110℃ for spray drying, to obtain a rosemary acid product with a content of 58% and a clear color after dissolving in water.

[0044] Example 2

[0045] Take 3000g rosemary dry leaves, after steam distillation, add 6 times the volume of dry leaves, 80% ethanol solution, extract twice at 70℃, each time for 50min, combine the filtrate and concentrate under reduced pressure to form a solid, then add 2 times the mass of dry leaves of water, stir and wash, filter, collect the filtrate; add 1% sulfuric acid solution to the filtrate, adjust the PH to 2.3; let stand for 30min to precipitate the analyte, then filter the solution, separate the precipitate, add 2 times the volume of isopropyl acetate to the filtrate, extract, let stand to separate the layers, release the water phase, and concentrate the extract under reduced pressure until there is essentially no solvent, then add 3 times the volume of water to the solvent in 2 portions, continue to concentrate under reduced pressure to remove the residual solvent, to obtain the treated liquid. The treated liquid is purified by adsorption with 0.4% acid-activated diatomite, then wash the diatomite with a small amount of water (1 / 10 of the filtrate) and combine it with the filtrate to form a uniform mixture; adjust the solid content of the mixture to 30%, and set the temperature to 100℃ for spray drying, to obtain a rosemary acid product with a content of 55% and a clear color after dissolving in water.

[0046] Example 3

[0047] Take 3000g rosemary dry leaves, rosemary dry leaves after steam distillation, add 6 times the volume of dry leaves, the concentration of 85% ethanol solution, extraction temperature 65 ℃ extraction twice, each extraction time is 50 min, the filtrate combined under reduced pressure concentrated into solid, add dry leaves quality 3 times water water stirring washing, filtration, collect the filtrate; add 5% citric acid solution to the filtrate, adjust PH to 2.5; static 30 min precipitate precipitate material after, the solution is filtered, separate the precipitate, add 2 times the volume of n-butanol to the filtrate, extract, static stratification, release the water phase, and the extract is reduced pressure concentrated to substantially no solvent, divided into 2 times each time to add solvent 3 times the volume of water, continue to reduce pressure concentration to bring out the residual solvent, get the treatment liquid. The treatment liquid is adsorbed and purified by 0.3% acid activated diatomite, and then washed with a small amount of water (filtrate 1 / 10) to form a uniform mixture. The solid content of the mixture is adjusted to 40%, and the temperature is set to 100 ℃ for spray drying. After drying, the rosemary acid product with a content of 51% and a clear color after water dissolution is obtained.

[0048] Comparative example 1

[0049] Take 3000g rosemary dry leaves, rosemary dry leaves after steam distillation, add 8 times the volume of dry leaves, the concentration of 80% ethanol solution, extraction temperature 65 ℃ extraction twice, each extraction time is 50 min, the filtrate combined under reduced pressure concentrated into solid, add dry leaves quality 3 times water water stirring washing, filtration, collect the filtrate; add 5% phosphoric acid solution to the filtrate, adjust PH to 2.5; static 30 min precipitate precipitate material after, the solution is filtered, separate the precipitate, add 2 times the volume of ethyl acetate to the filtrate, extract, static stratification, release the water phase, and the extract is reduced pressure concentrated to substantially no solvent, divided into 2 times each time to add solvent 3 times the volume of water, continue to reduce pressure concentration to bring out the residual solvent, get the treatment liquid. The bottom of the treatment liquid has insoluble paste, which cannot be spray dried into powder, and the obtained sample is viscous.

[0050] Comparative example 2

[0051] Take 3000g rosemary dry leaves, after steam distillation, add 8 times the volume of dry leaves, 80% ethanol solution, extraction temperature 65℃, extract twice, each time 50min, combine the filtrate and concentrate under reduced pressure into a solid, add 3 times the mass of dry leaves of water, stir and wash, filter, collect the filtrate; add 5% phosphoric acid solution to the filtrate, adjust the PH to 2.5; stand for 30min, precipitate the analyte, filter the solution, separate the precipitate, add 2 times the volume of ethyl acetate to the filtrate, extract, stand for separation, release the water phase, and concentrate the extract under reduced pressure until there is basically no solvent, then add 3 times the volume of water to the solvent in 2 times, continue to reduce pressure to concentrate to bring out the residual solvent, get the treatment liquid. The treatment liquid is purified by 0.5% macroporous resin adsorption, then washed with a small amount of water (1 / 10 of the filtrate) to wash the resin once, combined to the filtrate to form a uniform mixture; adjust the solid content of the mixture to 30%, set the temperature to 110℃ for spray drying, after drying, get rosemary acid powder product with content of 49%, slightly turbid after dissolving in water, deep color, and insoluble at the bottom.

Claims

1. A process for the preparation of highly soluble clear transparent rosmarinic acid characterized by: The rosemary dry leaves are subjected to water vapor distillation and ethanol extraction to obtain an extract; The extract is subjected to pressure reduction solidification, washing and filtration to obtain filtrate A; the filtrate A is added into acid liquor, and after precipitation, filtration, extraction and concentration, a precursor is obtained; the precursor is purified by acidified diatomite and dried to obtain the product; The extractant of the extraction process is an ester or an alcohol; the extraction conditions are as follows: extraction for 0.3-1 h under stirring at 20-45℃; The process of purification by acidified diatomite is as follows: the precursor is subjected to acidified diatomite mixture, the acidified diatomite mixture is washed with water, and the washing liquid is combined to obtain the product; the preparation process of the acidified diatomite is as follows: the mixture of diatomite and silica gel is adjusted to a pH of 1.5-2.5 by a pH adjuster, and is subjected to filtration and drying after standing for 0.5-1.5 h. The ester is one of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate and butyl acetate; the alcohol is one of n-butanol, isobutyl alcohol and isopropyl alcohol.

2. A process for the preparation of highly soluble clear transparent rosmarinic acid as claimed in claim 1, wherein: The water vapor distillation conditions are as follows: temperature of 80-120℃ and time of 20-40 min; the ethanol extraction is performed for ≥2 times.

3. A process for the preparation of a highly soluble clear transparent rosmarinic acid as claimed in claim 1 or 2, wherein the process comprises the steps of: The mass ratio of ethanol to rosemary dry leaves is 5-8:1; the ethanol extraction conditions are as follows: ethanol concentration of 75-90%, temperature of 60-70℃ and time of 40-60 min.

4. A process for the preparation of highly soluble clear transparent rosmarinic acid as claimed in claim 1, wherein: The acid liquor is one of phosphoric acid, hydrochloric acid, concentrated sulfuric acid, formic acid and citric acid, and the pH of the filtrate A is adjusted to 1-3.

5. A process for the preparation of highly soluble clear transparent rosmarinic acid as claimed in claim 1, wherein: The concentration process is as follows: the extract obtained after extraction is added with water in an amount of 2-5 times the volume, and is subjected to pressure reduction evaporation to a flowable paste, which is repeated for 1-3 times to obtain the product.

6. A process for the preparation of highly soluble clear transparent rosmarinic acid as claimed in claim 5, wherein the process comprises the steps of: The pressure reduction evaporation conditions are as follows: temperature of 65-75℃, vacuum degree of -0.07-0.1 MPa, and evaporation of the solvent to a flowable paste.

7. A process for the preparation of highly soluble clear transparent rosmarinic acid as claimed in claim 1, wherein the said process comprises the steps of: The filtration conditions of the acidified diatomite mixture are as follows: the amount of the acidified diatomite mixture is 0.1-1% of the precursor, and the vacuum degree is -0.04--0.07 MPa.

8. A process for the preparation of highly soluble clear transparent rosmarinic acid as claimed in claim 1, wherein: The drying mode is spray drying, the solid content of the feed is 20-40%, and the drying temperature is 90-120℃.

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