A peony root bark extract and a method for preparing the same

Abstract

The present application belongs to the field of cosmetic functional materials, and particularly relates to a peony root bark extract and a preparation method thereof. In the present application, a coarse water extract of peony root bark is obtained by using ultrasonic-assisted water extraction, then the coarse water extract is enriched by using D101 macroporous adsorption resin, eluted by 1,3-butanediol with a volume fraction of 60%, and the eluate is purified again by HP20 macroporous adsorption resin, and filtered by a polypropylene membrane to obtain the peony root bark extract. The experimental results of the present application show that the purity of paeonol in the peony root bark extract obtained by the method of the present application is as high as 68%, and the peony root bark extract prepared in the present application does not add any organic solvent with safety hazards in the whole process, is green and environmentally friendly, has low cost, does not add any preservative, has high safety factor, and the liquid form of the prepared extract can be directly used as a raw material or an auxiliary material in cosmetics.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of cosmetic functional raw materials, and particularly relates to a peony root bark extract and a preparation method thereof. BACKGROUND

[0002] With the improvement of people's material living standards, people's pursuit of beauty is also increasingly strong, so various different dosage forms and different functional cosmetics have emerged.

[0003] However, in order to have specific effects, various artificial synthetic additives are added to cosmetics on the market at the present stage, and the addition of these components is extremely easy to cause skin sensitivity or even damage. Since the extract of natural plants contains various bioactive components, it has become the main source of active ingredients in cosmetic raw materials.

[0004] Among them, peony is widely used as a raw material source of cosmetics because of its unique aroma and unique active ingredients such as paeonol, flavonoids, and paeoniflorin.

[0005] For example, in order to more efficiently extract active ingredients from peony root bark, mixed biological enzyme hydrolysis, organic solvent extraction, etc. are mostly used. Although the use of mixed enzyme preparations for enzymolysis of peony root bark can break down the barrier of plant cell walls and make active ingredients more fully dissolved, the cost of biological enzyme preparations is high, and the composition of the extracted solution after enzymolysis is extremely complex, which is difficult to purify. In addition, since the active ingredients in peony root bark can be well dissolved in organic matter, the use of organic solvents to extract the method can greatly dissolve the active ingredients therein, and can also shorten the extraction time. However, at the same time, it will also introduce more impurities. The most critical thing is that whether it is enzyme method or organic solvent extraction method to process peony root bark, the obtained extract contains residual enzyme preparations or organic solvents, and therefore cannot be directly used as a raw material for cosmetics and used. It needs to be treated complicatedly before use. Therefore, even if the content of active ingredients in the initial extract is high, after complicated treatment, not only a large amount of active ingredients is lost, but also the operation is complicated.

[0006] Of course, in order to avoid the disadvantages of the above extraction methods, some also use water vapor distillation method to process peony root bark, but this operation not only takes a long time, but also is easy to cause the decomposition of polyphenols and other active ingredients in peony root bark under high temperature conditions, and the obtained extract has poor activity.

[0007] In addition, the degree of purification of peony root bark after extraction directly determines the effect of the peony root bark as a cosmetic raw material. The existing purification method mainly uses specific adsorbent materials to purify the extract, however, due to the different structures of the adsorbent materials, different adsorbent materials have different adsorption effects on active ingredients with different polarities, combined with the differences in the types and concentrations of the selected elution solvents, which may ultimately result in different purification effects of the extract.

[0008] As disclosed in patent CN111606794A, a preparation method of peony root bark extract is disclosed, which uses composite enzymes + organic solvents for extraction, and uses chitosan for purification. Although the extract prepared by the method has high extraction rate and purity of paeonol, the extraction operation of the method is complex, the production cost is high, and the extract obtained by using organic solvents and composite enzyme preparations cannot be directly used as a cosmetic raw material. If the extract is directly used in skin care products and health care products, there may be certain safety risks.

[0009] In addition, patents CN103751058A and CN114432218A disclose the use of macroporous resin to enrich the extract, but neither discloses the specific adsorbent material used.

[0010] Therefore, it is of great significance to provide a preparation method of peony root bark extract with higher active ingredient content and higher safety factor, which can be directly used as a cosmetic raw material for industrialization, large-scale development and application of peony root bark. SUMMARY

[0011] To solve the above technical problems, the present application provides a peony root bark extract and a preparation method thereof.

[0012] In the present application, the peony root bark water extract is obtained by ultrasonic-assisted water extraction, and then the peony root bark extract is obtained by enrichment and purification of the peony root bark water extract by macroporous adsorbent resin. No organic solvent that may cause safety hazards is added in the whole preparation process, and the product is green and safe. Therefore, the peony root bark extract can be directly used as a raw material for cosmetics without any treatment. The detection results show that the purity of paeonol in the peony root bark extract prepared by the method of the present application is as high as 68%, and in addition to paeonol, the extract also contains a small amount of peony bark polysaccharide, flavone and other components. These components also have certain antioxidant effect. Therefore, the peony root bark extract obtained by the present application has higher safety factor, which mainly contains paeonol, and is supplemented by peony bark polysaccharide, flavone and other components.

[0013] The preparation method of the peony root bark extract provided by the present application comprises the following steps:

[0014] Step S1, taking dry peony root bark, crushing, sieving, ultrasonic assisted water extraction treatment, extraction temperature is 50~65℃, filtration, obtain peony root bark crude water extract;

[0015] Step S2, using macroporous adsorption resin to purify the peony root bark crude water extract obtained in step S1;

[0016] Step S3, the eluate after purification in step S2 is filtered by membrane to remove impurities, and the peony root bark extract is obtained.

[0017] The preparation method of the above-mentioned peony root bark extract comprises the following steps:

[0018] Preferably, in step S1, the frequency of the ultrasonic wave is 20~40 kHz, and the ultrasonic treatment time is 0.5~2h.

[0019] Preferably, in step S1, the frequency of the ultrasonic wave is 28 kHz, and the extraction time is 1h.

[0020] Preferably, in step S1, the mass-volume ratio of peony root bark powder to water is 1g:5~30mL.

[0021] Preferably, in step S1, the mass-volume ratio of peony root bark powder to water is 1g:20mL.

[0022] Preferably, in step S2, the macroporous adsorption resin is selected from at least one of HPD100, AB-8, D101 and HP20.

[0023] Preferably, in step S2, the macroporous adsorption resin is selected from at least one of HPD100 and HP20.

[0024] In step S2, first, the macroporous adsorption resin D101 is used to enrich the peony root bark crude water extract obtained in step S1, and after saturation, the alcohol solvent is used for elution, and then the macroporous adsorption resin HP20 is used for purification of the eluate, and the liquid flow rate during enrichment and elution is 1~3 BV / H.

[0025] More preferably, in step S2, the alcohol solvent is 1,3-butanediol, and the volume fraction of 1,3-butanediol is 60%.

[0026] Preferably, in step S3, the membrane is a polypropylene membrane.

[0027] In the present application, the principle of using the above method to prepare the peony root bark extract is as follows:

[0028] First, dry peony root bark is crushed into powder, and then the active ingredients in the peony root bark are extracted at 60℃ with pure water, while ultrasonic wave is used for auxiliary extraction.

[0029] On the one hand, compared with the method of using organic solvent for extraction, although the extraction rate is not high, the cost of raw materials is lower, and the whole extraction process is more green and environmental protection, and because the obtained water extract does not contain any residual organic solvent, the product can be directly used as a raw material for cosmetics without any subsequent treatment;

[0030] On the other hand, when the ultrasonic wave acts on the extraction system, the water molecules and the active components in the root bark extract of peony are vibrated violently in the process of ultrasonic wave propagation in water, so that small cavities are generated inside the particles, and when these small cavities rapidly expand and close, they will collide with each other violently, so that a larger pressure is generated in an instant, so that the peony root bark cells are broken, and under the action of the larger pressure, the active components dissolved in water are also torn, realizing the chain scission of the active components. The glycosides and other macromolecular components contained in the water extract of peony root bark are broken under the action of ultrasonic wave, so that the molecular weight of the active components in the extract is reduced, and the content of the active components is also significantly improved.

[0031] In addition, for the obtained water extract of peony root bark, a flow rate of 1-3 BV / H is first enriched by macroporous adsorption resin D101, and 60% 1,3-butanediol is used for elution, and the eluate is further purified by macroporous adsorption resin HP20, and finally filtered by polypropylene membrane. After this series of operations, most of the impurity components in the water extract of peony root bark are removed, and the final product is directly obtained in the form of liquid, and the purity of paeonol in the extract is up to 68%.

[0032] The D101 type macroporous adsorption resin has a large pore size and specific surface area, and has the characteristics of strong adsorption, which can adsorb the low polarity or non-polar components dissolved in water, and then desorb by suitable eluent to remove most of the water-soluble impurities in the crude water extract of peony root bark. In addition, the effluent after elution is further purified by HP20 type macroporous adsorption resin for the second time. Since HP20 is a reverse phase adsorption column, the impurity components contained in the extract can be further adsorbed by HP20 column and remain in the column, and the purity of the bioactive components such as paeonol in the effluent is greatly improved. In contrast, the adsorption rate and elution rate of HPD100 and AB-8 type macroporous resins for target components are low, so the purification effect is poor. D101 and HP20 type macroporous resins are more suitable for the enrichment of active components in the extract of peony root bark.

[0033] In addition, the D101 type macroporous adsorption resin is used to enrich the crude water extract of the root bark of Paeonia suffruticosa, and then 60% 1,3-butanediol is used for elution. If the content of 1,3-butanediol is too high, water-soluble impurities and other components in the extract are eluted, and the purity of paeonol in the obtained extract is low. Conversely, if the content of the eluent 1,3-butanediol is low, the elution effect of paeonol is greatly affected, and the content of paeonol is ultimately reduced.

[0034] Further, the paeonia suffruticosa root bark extract prepared by the above method is also the content to be protected by the present application. Moreover, the application of the paeonia suffruticosa root bark extract obtained by the above preparation method in the preparation of cosmetics also falls within the scope of the present application.

[0035] The present application has the following advantages:

[0036] (1) In the present application, the active ingredients in the root bark of Paeonia suffruticosa are extracted by ultrasonic-assisted water extraction method. With the help of cavitation effect of ultrasonic waves, the extraction time is shortened, and the content of active ingredients is improved. When the frequency of ultrasonic waves is 28 kHz, the energy generated by ultrasonic waves can break the chemical bonds with weak stability in macromolecular polysaccharides in the extract, so that the free hydroxyl groups are released, thereby improving the extraction rate of active ingredients such as paeonol;

[0037] (2) In the present application, D101 type and HP20 type macroporous adsorption resins are used in turn to purify the crude water extract of the root bark of Paeonia suffruticosa. The results show that after purification, the purity of paeonol in the obtained paeonia suffruticosa root bark extract is as high as 68%;

[0038] (3) The paeonia suffruticosa root bark extract provided by the present application uses pure water extraction process, and no organic solvent which may cause safety hazards is added in the whole preparation process. The eluent 1,3-butanediol used in purification is a common additive in cosmetics, and a small amount of addition has no damage to human skin. Therefore, the paeonia suffruticosa root bark extract obtained by the present application can be directly used as raw material or auxiliary material in cosmetics without any treatment, and has the advantage of high safety factor. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 It is the preparation process flow chart of the paeonia suffruticosa root bark extract in the present application embodiment 1;

[0040] Figure 2 It is the high performance liquid chromatogram of the paeonia suffruticosa root bark extract in the present application embodiment 1;

[0041] Figure 3 It is the preparation process flow chart of the paeonia suffruticosa root bark extract in the present application embodiment 2;

[0042] Figure 4 The high performance liquid chromatogram of the extract of the root bark of Paeonia suffruticosa in Example 2 of the present application is shown in Figure 1.

[0043] Figure 5 The high performance liquid chromatogram of the extract of the root bark of Paeonia suffruticosa in Example 3 of the present application is shown in Figure 2. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the present application, the present application will be further described in conjunction with specific embodiments.

[0045] Example 1

[0046] The process flow shown in Figure 1 is used to prepare the extract of the root bark of Paeonia suffruticosa. Figure 1

[0047] A method for preparing an extract of the root bark of Paeonia suffruticosa, comprising the following steps:

[0048] Step S1, dry the root bark of Paeonia suffruticosa and crush it through a 100-mesh sieve, add water to the root bark powder at a mass-to-volume ratio of 1 g:20 mL, and perform ultrasonic water extraction at 60°C, with a frequency of 28 kHz and a treatment time of 1 h, filter after the extraction is completed, and obtain a crude water extract of the root bark of Paeonia suffruticosa;

[0049] Step S2, first enrich the crude water extract of the root bark of Paeonia suffruticosa obtained in Step S1 using D101 macroporous adsorption resin at a flow rate of 2 BV / H, after saturation, elute with 1,3-butanediol at a volume fraction of 60%, at a flow rate of 2 BV / H, and then purify the obtained eluate using HP20 macroporous adsorption resin column, and collect the final eluate;

[0050] Step S3, filter the eluate obtained in Step S2 using a polypropylene membrane, and obtain the extract of the root bark of Paeonia suffruticosa.

[0051] The extract of the root bark of Paeonia suffruticosa obtained in this example is characterized using high performance liquid chromatography, and the high performance liquid chromatogram of the extract is shown in Figure 1. Figure 2

[0052] Figure 1 shows the high performance liquid chromatogram of the extract of the root bark of Paeonia suffruticosa in Example 1 of the present application. Figure 2 ​​The sample showed three peaks, from left to right: peony root bark polysaccharides, flavonoids, and paeonol. Paeonol had the highest content, reaching 68%, while the contents of other impurities were much lower than that of paeonol. This indicates that after enrichment with macroporous adsorption resin D101, elution with 60% 1,3-butanediol, and a second purification with HP20, the extract contained fewer types and amounts of impurities. The combined use of two macroporous adsorption resins can remove most of the water-soluble impurities in the peony root bark extract, resulting in a high content and purity of paeonol in the extract.

[0053] Example 2

[0054] A method for preparing peony root bark extract, specifically including the following steps:

[0055] Unlike Example 1, in step S2, only the D101 type macroporous adsorption resin was used to enrich the crude aqueous extract of peony root bark at a flow rate of 3 BV / H. After saturation, elution was carried out sequentially with 1,3-butanediol at volume fractions of 10%, 50%, and 90%. The target segment eluent was collected stepwise, combined, and then analyzed.

[0056] The preparation process of the peony root bark extract in this embodiment is as follows: Figure 3 As shown.

[0057] The peony root bark extract obtained in this embodiment was characterized by high performance liquid chromatography (HPLC). The HPLC chromatogram of the peony root bark extract is shown in the attached figure. Figure 4 .

[0058] Appendix Figure 4 The results show four distinct peaks. From left to right, the components are rutin, polysaccharide, paeoniflorin, and paeonol, with paeonol exhibiting the highest purity at 63%. This indicates that using only the D101 macroporous adsorption resin column for enrichment has limited purification capabilities for paeonol in the peony root bark extract, resulting in a high content and variety of impurities in the final extract. Furthermore, while elution with different concentration gradients of 1,3-butanediol can facilitate the elution of effective components of different polarities from the peony root bark in the extract, it may also lead to the loss of paeonol.

[0059] Example 3

[0060] A method for preparing peony root bark extract, specifically including the following steps:

[0061] Unlike Example 1, in step S2, the crude aqueous extract of peony root bark was enriched using D101 type macroporous adsorption resin at a flow rate of 3 BV / H. After saturation, elution was performed using 60% (v / v) of 1,3-butanediol, and the eluent was collected.

[0062] The high-performance liquid chromatogram of the eluent is attached. Figure 5 .

[0063] Appendix Figure 5 The sample showed multiple impurity peaks, including polysaccharides, flavonoids, paeoniflorin, and paeonol. Paeonol had a purity of 60%, and it was clear from the image that the paeonol content was not high, while the content of impurity components was relatively high. Therefore, if only D101 macroporous resin is used for purification, the purification effect of peony root bark extract will be poor and the purification will not be thorough.

[0064] Comparative Example 1

[0065] Unlike Example 1, in step S2, only HP20 macroporous resin was used to enrich the crude aqueous extract of peony root bark.

[0066] Comparative Example 2

[0067] Unlike Example 1, in step S2, only HPD100 macroporous resin was used to enrich the crude aqueous sap of peony root bark, and 60% 1,3-butanediol was used for elution.

[0068] Comparative Example 3

[0069] Unlike Example 1, in step S2, only AB-8 macroporous resin was used to enrich the crude aqueous extract of peony root bark, and 60% 1,3-butanediol was used for elution.

[0070] Comparative Example 4

[0071] Unlike Example 1, in step S2, 40% 1,3-butanediol was used for elution.

[0072] Comparative Example 5

[0073] Unlike Example 1, in step S2, 70% 1,3-butanediol was used for elution.

[0074] Comparative Example 6

[0075] Unlike Example 1, in step S2, 60% 1,2-propanediol was used for elution.

[0076] The purity of paeonol and the elution rate of macroporous adsorption resin in the peony root bark extracts obtained in Comparative Examples 1 to 6 are shown in Table 1 below.

[0077] Table 1 Purity of paeonol in peony root bark extract and elution rate of macroporous adsorption resin

[0078] Grouping Purity of paeonol (%) Elution rate (%) Example 1 68 90.58 Comparative Example 1 60 87.26 Comparative Example 2 58 88.54 Comparative Example 3 61 87.89 Comparative Example 4 62 85.56 Comparative Example 5 61 86.48 Comparative Example 6 49 86.38

[0079] From the data in Table 1, it can be seen that in Comparative Examples 1-3, the crude water extract of peony root bark was enriched and purified by using macroporous resin once, and the purity of paeonol in the peony root bark extract prepared was 58-61%, which was much lower than that of Example 1. This is because different types of macroporous adsorption resins have great differences in chemical structure, physical properties, pore size, etc. Therefore, even under the same extraction and elution conditions, the effect of using HP20, HPD100, AB8, etc. macroporous adsorption resins alone to enrich and purify the crude water extract of peony root bark is far inferior to that of using two resins in combination. In summary, using two macroporous resins in combination to enrich paeonol in the water extract of peony root bark is beneficial to remove most of the water-soluble impurities, thereby increasing the content and purity of paeonol in the peony root bark extract.

[0080] In addition, Comparative Examples 4-5 used 40% and 70% 1,3-butanediol for elution, respectively, and the purity of paeonol in the peony root bark extract obtained was 61-62%, and the elution rate of macroporous adsorption resin was also much lower than that of Example 1. This will affect the reuse of macroporous resin, and also cause waste of water extract, and the residual of part of paeonol active ingredients in macroporous resin will also lead to a decrease in the yield of peony root bark extract.

[0081] Comparative Example 6 used 60% 1,2-propanediol for elution. Although the difference in elution rate of macroporous adsorption resin is not significant compared with using 1,3-butanediol as eluent, the purity of paeonol obtained is only 49%, and compared with 1,3-butanediol, 1,2-propanediol is derived from propylene oxide from petrochemical sources, and its water absorption effect as a moisturizing agent is slightly worse, and even a high content may cause skin sensitivity. Therefore, 1,3-butanediol is more suitable for the extraction of paeonol in peony root bark extract than 1,2-propanediol.

Claims

1. A method for preparing an extract of Paeonia suffruticosa root bark, characterized by, The steps include the following: Step S1, dry peony root bark is crushed and passed through a 10-100 mesh sieve, water is added to the peony root bark powder at a mass-volume ratio of 1 g:5-30 mL, ultrasonic water extraction treatment is performed, the frequency of the ultrasonic waves is 20-40 kHz, the ultrasonic treatment time is 0.5-2 h, the extraction temperature is 50-65℃, after the extraction is completed, filtration is performed, and a peony root bark crude water extract is obtained; Step S2, the peony root bark crude water extract obtained in step S1 is first enriched using D101 macroporous adsorption resin, after saturation, elution is performed using 1,3-butanediol with a volume fraction of 60%, the eluate is then purified using an HP20 macroporous resin column, the liquid flow rate during enrichment and elution is controlled at 1-3 BV / H, and the final eluate is collected; Step S3, the eluate obtained in step S2 is filtered to remove impurities using a polypropylene membrane, and a peony root bark extract is obtained.

2. The peony root bark extract prepared using the preparation method of claim 1 is used in the preparation of cosmetics.

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