A Centella asiatica extract, its preparation method and uses

Abstract

This invention provides an extract of *Hedyotis diffusa*, its preparation method, and its uses. When the extract is measured under reversed-phase high-performance liquid chromatography, the peak area A of 6''-malonyl *Hedyotis diffusa* I is... M Peak area A with cypermethrin I B The ratio is less than 0.1, and the peak area A of free kaempferol is... K With A B The ratio shall not exceed 0.15. The preparation method includes: adjusting the pH of the aqueous extract of *Kaempferia galanga* to 11-13.5, and performing alkaline hydrolysis at 25-65°C for 20-60 minutes. This invention utilizes the difference in stability of malonyl bonds and glycosidic bonds under alkaline conditions to achieve the selective conversion of 6''-malonylkaempferol I to kaempferol I, increasing the content of kaempferol I while maintaining the integrity of the glycosidic bonds and inhibiting or controlling the formation of free kaempferol. The resulting extract can be used to prepare anti-inflammatory and antioxidant drugs or health foods.

Description

Technical Field

[0001] This invention belongs to the field of traditional Chinese medicine extraction technology, specifically relating to a herb extract, its preparation method, and its uses. Background Technology

[0002] Any discussion of prior art throughout the specification should not be construed as an admission that such prior art is well-known or constitutes part of common general knowledge in the art.

[0003] Centella asiatica ( Thesium chinense Turcz *Hydrocotyle sibthorpioides* is a plant belonging to the genus *Hydrocotyle* in the family Santalum album. The whole plant is used medicinally and is a traditional Chinese medicine. First recorded in the *Illustrated Materia Medica*, it has the effects of clearing heat and detoxifying, tonifying the kidneys and astringing essence. Clinically, it is used to treat diseases such as acute mastitis, lymphadenitis, pharyngitis, pneumonia, cystitis, and pyelonephritis.

[0004] Kaempferol contains abundant flavonoids, which are the main pharmacological basis of its medicinal properties. Among them, kaempferol-3-O-glucorhamnoside is one of the characteristic components of Kaempferol, which has anti-inflammatory and antioxidant pharmacological activities.

[0005] Studies have shown that, in addition to flavonoidin I, *Gynostemma pentaphyllum* contains a variety of structurally similar flavonoid glycosides, including acylated flavonoid glycoside derivatives. These acylated derivatives possess certain physiological functions within the plant, but their chemical stability differs from that of non-acylated flavonoid glycosides.

[0006] In the production process of traditional Chinese medicine extracts, the chemical composition of the extract directly affects the product's quality stability and efficacy. How to obtain *Centella asiatica* extract with a stable chemical composition and high content of active ingredients is a key issue to consider in the development of *Centella asiatica*-related products. Summary of the Invention

[0007] The inventors discovered in their research that, in addition to flavonoidin I, the aqueous extract of *Gynostemma pentaphyllum* also contains its malonyl derivative—6''-malonylflavonoidin I (CAS No.: 528606-92-0). This compound has a malonyl group attached to the 6''-hydroxyl group of glucose, forming an ester bond. Due to the presence of the malonyl ester bond, the compound's structure is unstable and prone to decomposition during storage and processing, leading to inconsistent product quality. Furthermore, the malonyl form of flavonoid glycosides has low bioavailability in vivo, which is detrimental to the efficacy of the drug.

[0008] In existing technologies, the treatment of malonylated flavonoid glycosides mainly employs heat treatment or enzymatic hydrolysis. Under heat treatment conditions, the cleavage efficiency of malonyl ester bonds is low and incomplete, and the glycosidic bonds between the flavonoid aglycone and the sugar moiety may also break, leading to the formation of free kaempferol aglycone and resulting in the loss of active ingredients. Although enzymatic hydrolysis offers better selectivity, it suffers from problems such as high cost, complex processes, and unstable enzyme activity, making it difficult to apply industrially.

[0009] Therefore, it is necessary to develop a method that can efficiently convert 6''-malonyl gentianin I into gentianin I while avoiding glycosidic bond breakage, so as to improve the content and stability of gentianin I in gentian extract.

[0010] To solve the above-mentioned technical problems, the present invention provides the following technical solution: First aspect The first aspect of this invention provides a Centella asiatica extract. The extract, when measured under the following reversed-phase high-performance liquid chromatography conditions, meets a specific peak area ratio index.

[0011] The reversed-phase high-performance liquid chromatography (RP-HPLC) conditions were as follows: the column was an octadecylsilane-bonded silica column (C18), with dimensions of 4.6 mm × 250 mm and a packing particle size of 5 μm; the mobile phase was acetonitrile (A) and 0.2% formic acid aqueous solution (B), with gradient elution. The gradient elution program was as follows: 0 to 15 minutes 15% A, 15 to 17 minutes A phase increasing from 15% to 20%, 17 to 32 minutes 20% A, 32 to 42 minutes A phase increasing from 20% to 100%, and further, 42 to 52 minutes was the reequilibration time, during which A phase decreased from 100% to 15%; the detection wavelength was 365 nm; the column temperature was 30 °C; and the flow rate was 0.8 mL / min.

[0012] In some embodiments, the gradient procedure may be further followed by steps for rinsing the column and / or rebalancing to ensure stable chromatographic separation conditions and facilitate repeatability.

[0013] Under the above chromatographic conditions, let the peak area of ​​6''-malonyl cypermethrin I be A. M The peak area of ​​cypermethrin I is A. B The peak area of ​​free kaempferol is A. K The extract of Centella asiatica of the present invention satisfies the following condition: A M With A B The ratio is less than 0.1; and A K With A B The ratio shall not exceed 0.15.

[0014] The above-described reversed-phase high-performance liquid chromatography conditions are the basis for calculating A in this invention. M A B AK The benchmark detection conditions for its related ratios. Unless otherwise stated, whether the sample meets the requirements of A as described in the first aspect of the present invention. M / A B and A K / A B The indicators shall, in principle, be based on the measurement results under the aforementioned benchmark testing conditions.

[0015] In some embodiments, the term "Centella asiatica extract" as used herein includes a liquid extract obtained by alkaline hydrolysis according to the method of the present invention, followed by cooling, optional pH adjustment, and clarification; and the corresponding extract form obtained by further concentrating, drying, or reconstituted the liquid extract without substantially altering its aforementioned relative compositional characteristics. Samples in different physical forms can be prepared into test solutions according to the detection methods described in this specification, and their compliance with the aforementioned A criteria can be determined under the same detection system. M / A B and A K / A B index.

[0016] In some embodiments, under the reversed-phase high-performance liquid chromatography conditions, the characteristic peak of free kaempferol was not detected (S / N<3).

[0017] In some embodiments, the above chromatographic conditions can achieve the separation and peak area integration of the characteristic peaks of three compounds: kaempferol I, 6''-malonylkaempferol I, and free kaempferol. The attribution of the characteristic peaks can be confirmed by matching them with the retention time and ultraviolet spectrum of the corresponding reference standards (the retention time may vary depending on the instrument and column conditions).

[0018] In some embodiments, the A of the Centella asiatica extract M With A B The ratio should not exceed 0.06. Under optimal conditions, this ratio can be reduced to below 0.01, meaning that the malonyl compound is almost completely converted.

[0019] In some embodiments, the signal-to-noise ratio (S / N) of the chromatographic peak of 6''-malonyl pachyrhizine I is less than 3. When the S / N of the chromatographic peak of a malonyl compound is less than 3, it is considered that the compound has been completely converted or its residue is negligible. This indicates that the 6''-malonyl pachyrhizine I is below the limit of detection.

[0020] In some embodiments, the A of the Centella asiatica extract K With A B The ratio shall not exceed 0.08, preferably not exceeding 0.06. In some embodiments, A K The characteristic peaks were not detected (S / N<3).

[0021] In some embodiments, the concentration of gentianin I in the *Gnaphalium affine* extract is determined using the external standard method to be not less than 0.40 mg / mL. The external standard method establishes a standard curve using gentianin I as a reference standard, and the concentration is calculated based on the peak area of ​​gentianin I in the sample. The concentration refers to the concentration of the *Gnaphalium affine* alkaline hydrolysate before concentration or dilution, i.e., the concentration of gentianin I in the stock solution of the alkaline hydrolysate prepared according to the method of this invention. In some embodiments, the term "stock solution of alkaline hydrolysate" as used herein refers to the reaction solution itself obtained after cooling following the hydrolysis reaction, optionally adjusting the pH to 6 to 8, and removing insoluble matter by filtration or centrifugation, excluding the test solution obtained solely for detection purposes after rotary evaporation, reconstitution, and volume adjustment. For samples that have been concentrated, dried, or reconstituted, the gentianin I content can be determined using the external standard method described in this specification, and the concentration can be recalculated back to the stock solution concentration by the corresponding multiple.

[0022] In an embodiment of the present invention, the ratio of the herbal extract to water is 1:8 to 1:15 (g / mL), preferably 1:14 (g / mL), and the concentration of herbal extract I in the original solution after water extraction and alkaline hydrolysis is 0.42 to 0.46 mg / mL.

[0023] In some embodiments, the Centella asiatica extract is prepared by alkaline hydrolysis of a Centella asiatica aqueous extract, wherein the alkaline hydrolysis includes adjusting the pH of the aqueous extract to 11 to 13.5 and maintaining it at 25°C to 65°C for 20 to 60 minutes.

[0024] In some preferred embodiments, the alkaline hydrolysis treatment is performed at a pH of 12.5 to 13, a temperature of 53 to 58°C, and a time of 25 to 35 minutes. Under these preferred conditions, 6''-malonyl cypermethrin I can be completely converted, and the peak area of ​​cypermethrin I can increase by up to 17.9%, while A K / A B It can be controlled below 0.08.

[0025] In some embodiments, the alkaline hydrolysis treatment uses a sodium hydroxide solution or a potassium hydroxide solution to adjust the pH, the concentration of which is 0.5 to 2.5 mol / L.

[0026] In some implementations, the aqueous extract of Centella asiatica is obtained by extracting Centella asiatica by decoction or reflux extraction.

[0027] In some implementations, A M / A B Not exceeding 0.06; in a further embodiment, A M / A B Not exceeding 0.01; in a further embodiment, 6''-malonyl baicalin I is below the detection limit.

[0028] In some implementations, A K / A B Not exceeding 0.08; preferably not exceeding 0.06; in a further embodiment, free kaempferol was not detected.

[0029] In some embodiments, the preferred conditions for alkaline hydrolysis treatment are pH 12.5 to 13, temperature 53 to 58°C, and time 25 to 35 minutes.

[0030] In some embodiments, the concentration of gentianin I in the alkaline hydrolysate stock solution prepared according to the method of the present invention is 0.42 to 0.46 mg / mL.

[0031] In some embodiments, 6''-malonyl kaempferol I is an acylated flavonoid glycoside with a malonyl group introduced at the 6'' position of the glycosyl group, where the malonyl group is linked to the glycosyl group by an ester bond. Under controlled alkaline conditions, the ester bond is relatively easy to hydrolyze, thereby reducing the acylated component and generating the corresponding deacylated flavonoid glycoside (e.g., kaempferol I). In contrast, the glycosidic bond of the flavonoid glycoside may break under excessively alkaline, excessively high temperature, or excessively long conditions, generating byproducts such as aglycones (e.g., free kaempferol).

[0032] Based on the above differences, the present invention simultaneously defines A M / A B With A K / A B By linking "sufficient deacylation" and "glycosidic bond retention" with quantifiable indicators under the same detection system, the range of extracts chemically corresponds to "selective deacylation," and this avoids the situation where samples with damaged glycosidic bonds are included in the same product specification based solely on the degree of deacylation. The core of this invention is not solely pursuing A... M / A B Instead of reducing, A is constrained simultaneously under the same detection system. M / A B With A K / A B This characterizes the coexistence of "sufficient deacylation" and "glycosidic bond retention." Therefore, even if certain more severe conditions can further reduce A... M / A B However, if it simultaneously causes A K / A B If the concentration of free kaempferol is elevated or present, then the sample is not the target extract sought by this invention.

[0033] In the comparison between the control aqueous extract and the extract of the present invention, A can be observed. M / A B Significantly reduced and A K / A BIt remains at a low level; while in comparative examples under harsh conditions such as strong bases or strong acids, although A M / A B It can be reduced, but A will appear. K And caused A K / A B The level will rise, thus reflecting an increased risk of glycosidic bond breakage.

[0034] When A M / A B When the concentration is controlled below 0.1, the chromatographic fingerprint drift of the sample under storage or accelerated conditions can be reduced. Reducing the proportion of malonylated precursors helps mitigate the risk of compositional fluctuations caused by the transformation of these precursors during subsequent processing or storage, thereby facilitating consistent quality control. In some embodiments, the untreated *Lysimachia christinae* aqueous extract and the *Lysimachia christinae* extract obtained according to the method of this invention can be placed under the same storage or accelerated conditions, and A can be determined at predetermined time points using the aforementioned HPLC method. M A B A K A M / A B A K / A B The changes in the content of cypermethrin I were analyzed to evaluate the risk of compositional fluctuations and quality consistency of the sample during storage. The "chromatographic fingerprint drift" referred to in this paper can be characterized by combining the aforementioned characteristic peak area ratios and changes in the content of the target component before and after storage.

[0035] Second aspect A second aspect of the present invention provides a method for preparing the above-mentioned Centella asiatica extract, comprising the following steps: Step (a): Extract the herb *Cynanchum paniculatum* with water to obtain *Cynanchum paniculatum* aqueous extract; Step (b): Add an alkaline solution to the aqueous extract of Centella asiatica to adjust the pH to 11 to 13.5, and carry out the hydrolysis reaction at 25°C to 65°C for 20 to 60 minutes. Step (c): After the hydrolysis reaction is completed, the mixture is cooled and separated to obtain the Centella asiatica extract.

[0036] For different batches of medicinal materials, different material-to-liquid ratios, different degrees of extract concentration, different equipment volumes, different heat transfer conditions, or different stirring conditions, those skilled in the art can make routine fine adjustments to pH, temperature, and reaction time based on the process principles, parameter ranges, and the aforementioned endpoint detection indicators disclosed in this specification to obtain the desired results. M / A B and A K / A BThe preferred conditions described above are for illustrating embodiments with better overall effects and do not imply that other conditions within the scope of these conditions cannot be used to implement the invention.

[0037] In some embodiments, in step (a), the *Centella asiatica* herb is cut into segments or pulverized before extraction, wherein the segments are 0.5 to 8 cm in length, or the powder can pass through a No. 1 sieve. The material-to-liquid ratio of *Centella asiatica* herb to water is 1:5 to 1:15 (mass-volume ratio, g / mL), preferably 1:14 (g / mL). Reflux extraction is used, with 2 to 4 extractions, each lasting 1 to 2 hours. For example, 1000 g of *Centella asiatica* herb is cut into segments approximately 2 cm long, and 10 times the amount of water (10 liters) is added. The mixture is refluxed twice, each time for 1.5 hours. The extracts are then combined and concentrated to approximately 1000 mL.

[0038] In some embodiments, step (b) involves adjusting the pH using a sodium hydroxide or potassium hydroxide solution with a concentration of 0.5 to 2.5 mol / L. For example, approximately 35 mL of a 2.5 mol / L sodium hydroxide solution is added to 1000 mL of *Gnaphalium affine* aqueous extract while stirring, and the pH is monitored with a pH meter until it reaches 12.9.

[0039] In some implementations, step (c) includes cooling the reaction solution to 4 to 25°C, adjusting the pH to 6 to 8, and filtering or centrifuging to remove insoluble matter. Adjusting the pH to neutral aims to terminate the hydrolysis reaction and avoid the impact of strongly alkaline products on subsequent processes or formulation stability.

[0040] In some embodiments, the *Centella asiatica* extract prepared by the above method, when measured under the reversed-phase high-performance liquid chromatography conditions described in this invention, satisfies A. M / A B Less than 0.1 and A K / A B Not exceeding 0.15.

[0041] In some implementations, A M / A B Not exceeding 0.06; in a further embodiment, A M / A B Not exceeding 0.01; in a further embodiment, 6''-malonyl baicalin I is below the detection limit.

[0042] In some implementations, A K / A B Not exceeding 0.08; preferably not exceeding 0.06; in a further embodiment, free kaempferol was not detected.

[0043] In some embodiments, the preferred conditions for alkaline hydrolysis treatment are pH 12.5 to 13, temperature 53 to 58°C, and time 25 to 35 minutes.

[0044] In some embodiments, the concentration of gentianin I in the alkaline hydrolysate stock solution prepared according to the method of the present invention is 0.42 to 0.46 mg / mL.

[0045] For different raw material batches, extraction concentrations, equipment volumes, and heat transfer / stirring conditions, those skilled in the art can make routine fine-tuning of pH, temperature, and time based on the process principles, parameter ranges, and endpoint detection indicators disclosed in this specification to obtain the desired results. M / A B and A K / A B Extracts of the indicators; preferred conditions are used to illustrate implementation methods with better overall effects, and do not mean that the invention cannot be implemented under non-preferred conditions.

[0046] The uses described in the third aspect and the formulations described in the fourth aspect of this invention are both based on the *Centella asiatica* extract with controlled relative composition characteristics described in the first aspect. Its main technical significance lies in providing a more suitable extract basis for raw material quality control, formulation application, and subsequent quality verification by reducing the proportion of malonylation precursors and controlling the level of aglycone byproducts.

[0047] Third aspect The third aspect of this invention provides the use of the Centella asiatica extract described in the first aspect above.

[0048] The *Gnaphalium affine* extract of the present invention can be used to prepare anti-inflammatory drugs. Gnaphalogenin I has significant anti-inflammatory activity and can inhibit the release of inflammatory factors. The extract of the present invention has a high content of gnaphalogenin I and few impurities, which is beneficial to the exertion of its anti-inflammatory efficacy.

[0049] The extract of *Gnaphalium affine* of this invention can also be used to prepare drugs or health foods with antioxidant functions. Gnaphalogenin I is a flavonol glycoside with good antioxidant activity, capable of scavenging free radicals and protecting cells from oxidative damage.

[0050] The extract of *Centella asiatica* of this invention can also be used to prepare *Centella asiatica* granules, tablets, or capsules. *Centella asiatica* granules are a traditional Chinese medicine made from *Centella asiatica*, possessing the effects of clearing heat and reducing inflammation, relieving cough and resolving phlegm. The extract of this invention can be used as a raw material for the above-mentioned preparations, providing stable and high-content active ingredients.

[0051] In some embodiments, the anti-inflammatory or antioxidant related functions of the extracts of the present invention can be evaluated in comparison with commonly used in vitro or in vivo evaluation models in the art, and should preferably be compared with the corresponding Centella asiatica aqueous extract that has not undergone alkaline hydrolysis under the same administration or treatment conditions to examine the correlation between the compositional characteristics of the extracts and their functional performance.

[0052] Fourth aspect A fourth aspect of this invention provides a preparation of *Centella asiatica* containing the *Centella asiatica* extract described in the first aspect of this invention as an active ingredient, and pharmaceutically acceptable excipients. The dosage form of the preparation may be granules, tablets, capsules, pellets, or powder.

[0053] When preparing granules, the *Centella asiatica* extract of this invention can be taken, and excipients such as dextrin and sucrose can be added, followed by granulation, drying, and sizing. When preparing tablets, the dried powder of the *Centella asiatica* extract of this invention can be taken, and excipients such as starch and magnesium stearate can be added, followed by tablet compression, and coating if necessary. When preparing capsules, the dried powder of the *Centella asiatica* extract of this invention can be filled into gelatin capsules.

[0054] Terminology Definition For different batches of Bai Rui Cao medicinal materials, the absolute peak area and absolute content of relevant compounds may differ; however, under the same detection system, A M / A B and A K / A B As a relative composition indicator, it can still be used to characterize the compositional features of the Centella asiatica extract of the present invention.

[0055] Unless otherwise stated, the terms used in this specification have the following meanings.

[0056] "Kaempferol I" refers to kaempferol-3-O-glucorhamnoside, with the English name kaempferol-3-O-glucorhamnoside and the molecular formula C1. 27 H 30 O 15 It has a molecular weight of 594.52 and CAS number 40437-72-7. Under the HPLC conditions described in this invention, its retention time is approximately 24-26 minutes.

[0057] "6''-Malonyl-Pyrocyanin I" refers to an esterified derivative formed by attaching a malonyl group to the 6''-position hydroxyl group of pyrocyanin I, with the molecular formula C. 30 H 32 O 18 It has a molecular weight of 680.56 and CAS number 528606-92-0. Under the HPLC conditions described in this invention, its retention time is approximately 30-33 minutes.

[0058] "Free kaempferol" refers to the aglycone portion of kaempferol I, i.e., kaempferol (molecular formula C10). 15 H 10 O6, molecular weight 286.24. When the glycosidic bond of kaempferol I is broken, free kaempferol is released. Under the HPLC conditions described in this invention, its retention time is approximately 41 minutes.

[0059] A M “A” B “A” K "These refer to the peak areas of 6''-malonyl kaempferol I, kaempferol I, and free kaempferol, as determined under the HPLC conditions described in this invention." A M / A B “A” K / A B "These refer to the ratios of the peak areas mentioned above."

[0060] A M / A B "and "A K / A B "These ratios are all used to characterize the relative compositional relationships of relevant components in the sample. The aforementioned ratios were obtained under the same reversed-phase high-performance liquid chromatography conditions and corresponding test sample preparation conditions described in this specification, and are used to determine whether the sample has reached the selective deacylation state described in this invention."

[0061] The "limit of detection" refers to the lowest detectable concentration corresponding to a signal-to-noise ratio (SNR) of 3. When the SNR of a compound's chromatographic peak is less than 3, the compound is considered to be below the limit of detection. The SNR is calculated using the peak-to-peak method of the chromatography workstation, with the noise range selected as the baseline noise within a 1-minute interval before and after the retention time of the target peak.

[0062] "Control" refers to the aqueous extract of *Centella asiatica* obtained directly from the same batch of *Centella asiatica* herbs under the same extraction conditions without alkaline hydrolysis treatment. The same extraction conditions include the same material-to-liquid ratio, number of extractions, extraction time, and degree of concentration.

[0063] Beneficial effects Compared with the prior art, the present invention has the following beneficial effects.

[0064] Achieving targeted and efficient enrichment of the key pharmacodynamic component, cypermethrin I, is beneficial for increasing its relative proportion. This invention introduces a controllable alkaline hydrolysis step into the aqueous extract stage of *Hedyotis diffusa*, utilizing the difference in reactivity between malonyl ester bonds and glycosidic bonds under alkaline conditions to directionally convert unstable acylated precursors such as 6''-malonylcypermethrin I into the target pharmacodynamic component, cypermethrin I, thereby increasing its relative proportion. For example, in some embodiments, this method increases the content of cypermethrin I compared to the aqueous extract, with an increase of up to 17.9% under optimized conditions, significantly amplifying the proportion of the main pharmacodynamic component and laying a solid foundation for preparing more functional *Hedyotis diffusa* formulations.

[0065] This process improves the product's quality stability and purity, facilitating consistent quality control. It significantly reduces the content of unstable acylation precursors (malonylation precursors) in the extract. This reduces the risk of compositional fluctuations caused by further transformation of these precursors during subsequent processing or storage, thus helping to establish stable quality control indicators. For example, in some embodiments, under optimal conditions, the degradation rate of 6''-malonyl cymosin I can reach 100%, reducing potential spontaneous transformations and structural rearrangements during subsequent production and storage, effectively improving product quality fluctuations during storage, and contributing to the establishment of stable quality standards.

[0066] This invention balances the degree of acylation with structural preservation. M / A B and A K / A B It characterizes the degree of malonyl removal and the retention of glycosidic bonds, thereby helping to avoid including samples with damaged glycosidic bonds in the same product range simply by judging the sample based on the degree of acyl removal.

[0067] This invention ensures high selectivity and structural integrity during the conversion process. By precisely controlling process parameters such as pH 11–13.5, temperature 25–65℃, and time 20–60 min, the invention achieves preferential hydrolysis of malonyl ester bonds while effectively protecting the kaempferol-3-O-glycosidic bonds in the flavonoid glycoside skeleton. This selectivity guarantees the structural integrity of the active ingredient, cypermethrin I. Furthermore, this invention establishes quantifiable intrinsic product indicators (such as A...). K / A B (ratios, etc.) to facilitate rapid detection and determination of product quality without the need for complex control samples.

[0068] The process is simple, easy to scale up, low-cost, and environmentally friendly: This invention adopts a process route of water extraction followed by a one-step alkali treatment. The alkaline solution used is readily available, eliminating the need for special solvents or expensive enzyme preparations. The reaction conditions are mild and controllable, the reaction time is short, the operation is safe, and the equipment requirements are low. It is easy to integrate with existing Centella asiatica water extraction production lines and is very suitable for industrial-scale implementation on existing traditional Chinese medicine preparation production lines. Attached Figure Description

[0069] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 The image shows the HPLC chromatogram of the aqueous extract of Centella asiatica (aqueous extract W) from Example 1.

[0070] Figure 2 The image shows the HPLC chromatogram of the hydrolysate of *Centella asiatica* (treatment solution T) in Example 1.

[0071] Figure 3 The image shows the HPLC chromatogram of the aqueous extract of Centella asiatica (aqueous extract W) in Example 2.

[0072] Figure 4 The image shows the HPLC chromatogram of the hydrolysate of *Centella asiatica* (treatment solution T) in Example 2.

[0073] Among them, the characteristic peak of kaempferol I was observed at approximately 24-26 min; the characteristic peak of 6''-malonylkaempferol I was observed at approximately 30-33 min; and the characteristic peak of free kaempferol was observed at approximately 41 min (not detected in the hydrolysate of kaempferol alkaloids in Examples 1-2). Detailed Implementation

[0074] This application is further illustrated with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope thereof. Experimental methods not specifically described in the embodiments are generally performed under conventional conditions or conditions recommended by the manufacturer.

[0075] Unless otherwise defined, all technical and scientific terms used in this application shall have meanings familiar to those skilled in the art. Unless otherwise specified, all reagents or raw materials used in this application are obtainable through conventional means and used in accordance with conventional methods or product instructions in the art. Furthermore, any methods or materials similar to or equivalent to those described may be applied to the methods of this application. The preferred embodiments and materials described in this application are for illustrative purposes only.

[0076] Unless otherwise specified, all data used in this specification to illustrate the technical effects of the present invention can be compared horizontally under the same detection system. For samples obtained under different treatment conditions, the effect should be judged based on the same batch of raw materials, the same preparation method for the test sample, and the same chromatographic evaluation system, thereby ensuring that A... M / A B A K / A B The concentrations of cypermethrin I, DM, and IB are comparable.

[0077] The reaction formulas of embodiments of the present invention are as follows:

[0078] I. Detection Methods The content of kaempferol I in the sample was determined by reversed-phase high-performance liquid chromatography, and the peak areas of 6''-malonylkaempferol I and free kaempferol were determined simultaneously to characterize their relative levels.

[0079] 1. Test solution Accurately measure 4 mL of *Centella asiatica* aqueous extract, evaporate to dryness, add 50% ethanol and sonicate to dissolve, transfer to a 25 mL volumetric flask, add 50% ethanol to volume, shake well, filter through a 0.45 μm microporous membrane, and use the filtrate as a control sample of *Centella asiatica* aqueous extract; accurately measure 4 mL of *Centella asiatica* aqueous extract, prepare *Centella asiatica* treatment solution T according to the hydrolysis method of this patent, evaporate *Centella asiatica* treatment solution T to dryness, add 50% ethanol and sonicate to dissolve, transfer to a 25 mL volumetric flask, add 50% ethanol to volume, shake well, filter through a 0.45 μm microporous membrane, and use the filtrate as a test sample of *Centella asiatica* treatment solution; The dilution factor of the test solution can be adjusted according to the response of the characteristic peak of cypermethrin I to ensure that the target peak is within the linear range of the detector and does not saturate.

[0080] The test solution should preferably be tested within 24 hours after preparation; if temporary storage is required, it should preferably be stored at 2–8°C in a light-proof and sealed container.

[0081] Unless otherwise specified, all samples in the examples and comparative examples were measured under the same reversed-phase high-performance liquid chromatography conditions.

[0082] 2. Chromatographic conditions The chromatographic column was packed with octadecylsilane-bonded silica gel, measuring 4.6 mm × 250 mm with a particle size of 5 μm. The mobile phase was acetonitrile (A) – 0.2% formic acid aqueous solution (B), with a gradient elution program as follows: 0–15 min 15% A, 15–17 min A increasing from 15% to 20%, 17–32 min 20% A, 32–42 min A increasing from 20% to 100%, and further, 42–52 min reequilibration, during which A decreased from 100% to 15%. After analysis, the mobile phase was restored to initial conditions and the column was equilibrated to ensure the stability of retention times between adjacent injections. The detection wavelength was 365 nm; the column temperature was 30 °C; the flow rate was 0.8 mL / min; and the injection volume was 10 μL.

[0083] Under the above chromatographic conditions, the retention time of kaempferol I was approximately 24-26 minutes, the retention time of 6''-malonylkaempferol I was approximately 30-33 minutes, and the retention time of free kaempferol was approximately 41 minutes.

[0084] The chromatographic conditions described in this section are the aforementioned baseline detection conditions, used for A in samples. M A B A K And the calculation of its related ratios.

[0085] 3. Chromatographic peak assignment Under the above chromatographic conditions, the characteristic peaks of kaempferol I, 6''-malonylkaempferol I, and free kaempferol were identified by comparing their retention times with the corresponding reference standards. Different instrument systems, column conditions, and gradient fine-tuning conditions may result in slight deviations in the retention times of each characteristic peak, but this does not affect peak identification through reference standard comparison.

[0086] When performing method transfer, peak assignment confirmation, or repeatability verification between different instrument systems, those skilled in the art can do so without changing the characteristic peak assignment, peak separation relationship, and A. M / A B A K / A B Under the premise of determining the substance, routine fine-tuning should be performed on the injection volume, rebalancing time and other non-substantial analytical conditions; if necessary, routine adjustments can be made to column temperature, flow rate and other conditions according to the actual situation of the instrument system, but should be limited to not substantially affecting the separation of the three characteristic peaks and the determination of the area ratio.

[0087] The above-mentioned routine fine-tuning is only used for method transfer and verification, and does not change the defining role of the aforementioned benchmark detection conditions in the product definition of this invention; when it is necessary to determine whether the sample meets the requirements of A in the first aspect of this invention... M / A B and A K / A BWhen determining the indicators, the results measured under the aforementioned benchmark testing conditions shall, in principle, be the standard.

[0088] 4. Quantitative method for reference solution and gentianin I The content of cypermethrin I was determined using the external standard method. An appropriate amount of cypermethrin I reference standard was accurately weighed, dissolved in methanol, and quantitatively diluted to prepare a reference solution. The solution was then injected and analyzed. A linear regression was performed on the peak area against the concentration to obtain a standard curve. The concentration was calculated from the standard curve based on the peak area of ​​the sample solution.

[0089] Let A be the peak area of ​​6''-malonyl cypermethrin I. M The peak area of ​​cypermethrin I is A. B The peak area of ​​free kaempferol is A. K .

[0090] 5. Parallel determination, repeatability, and detection limit processing Unless otherwise stated, liquid extracts, concentrated pastes obtained by vacuum concentration, powders obtained by spray drying, or their reconstituted samples can all be used to prepare test solutions for detection according to the methods described in this section. Appropriate dilution, reconstitution, or volume adjustment of the test sample for detection purposes generally does not substantially change the relative compositional relationship characterized by AM / AB and AK / AB, provided that the target peak is within the linear range of the detector.

[0091] All samples were measured in parallel to assess repeatability. For example, at least three parallel measurements were performed on each sample, the average value was taken as the peak area data, and the relative standard deviation (RSD) was calculated. In the embodiments of this application, the RSD of the peak area measurements of kaempferol I, 6''-malonylkaempferol I, and free kaempferol were all less than 5%, indicating that the measurement results had good repeatability.

[0092] When a target peak is not detected within the corresponding retention time window (S / N < 3), it is determined to be undetectable (ND). For ease of table presentation and calculation, this peak area is recorded as 0 (ND) or 0, and is substituted with a value of 0 in the calculation of AM / AB, AK / AB, and DM. The "0" only indicates that it was not detected, and does not mean that the actual peak area is zero.

[0093] Unless otherwise specified, experiments comparing the effects of different treatment conditions on the composition of Centella asiatica extract should use the same batch of Centella asiatica herbal material and be conducted under the same material-to-liquid ratio, extraction method, concentration level, sample preparation steps, and reversed-phase high-performance liquid chromatography conditions. During comparison, all conditions should be kept consistent except for the factor under investigation. If necessary, each sample can be prepared independently and / or analyzed in parallel, and the results should be analyzed using A... M / A B A K / A BThe concentration of cypermethrin I, the rate of decrease in the peak area of ​​6''-malonylcypermethrin I (DM), and / or the increase in cypermethrin I (IB) were used as evaluation indicators.

[0094] II. Implementation Examples Example 1 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0095] S2: Add NaOH solution to the aqueous extract obtained in step S1 to adjust the pH of the system to 12.9. Stir magnetically in an oil bath at 55°C for 30 minutes. After the reaction, add acid to adjust the pH to neutral (pH=7±1), let stand at 4°C for 30 minutes, make up to volume, and filter to obtain the treated solution T (a hydrolysate of *Centella asiatica*, i.e., the *Centella asiatica* extract described in this invention).

[0096] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0097] Detection results: The results are shown in Tables 1-4. In this embodiment, T satisfies A. M / A B <0.01 and A K / A B <0.01; the concentration of cypermethrin I increased from 0.39 mg / mL to 0.46 mg / mL (increase IB = 17.9%); the peak area reduction rate of 6''-malonylcypermethrin I was DM = 100%.

[0098] Example 2 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0099] S2: Add NaOH solution to the aqueous extract obtained in step S1 to adjust the pH of the system to 11. Stir magnetically in an oil bath at 55°C for 30 minutes. After the reaction, add acid to adjust the pH to neutral (pH=7±1), let stand at 4°C for 30 minutes, make up to volume, and filter to obtain the treated solution T (a hydrolysate of *Centella asiatica*, i.e., the *Centella asiatica* extract described in this invention).

[0100] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0101] Detection results: See Tables 1-4. In this embodiment, T satisfies A. M / AB <0.01 and A K / A B <0.01; the concentration of cypermethrin I increased from 0.39 mg / mL to 0.45 mg / mL (IB=15.4%); DM=100%.

[0102] Example 3 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0103] S2: Add NaOH solution to the aqueous extract obtained in step S1 to adjust the pH of the system to 11. Stir the reaction magnetically at 25°C for 1 hour. After the reaction is complete, add acid to adjust the pH to neutral (pH=7±1), let it stand at 4°C for 1 hour, make up to volume and filter to obtain the treatment solution T (a hydrolysate of *Centella asiatica*, i.e., the *Centella asiatica* extract described in this invention).

[0104] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0105] Detection results: See Tables 1-4. In this embodiment, T satisfies A. M / A B = 0.06 and A K / A B <0.01; the concentration of cypermethrin I increased from 0.39 mg / mL to 0.43 mg / mL (IB=10.3%); DM=59.8%.

[0106] Example 4 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0107] S2: Add NaOH solution to the aqueous extract obtained in step S1 to adjust the pH of the system to 13.30. Stir magnetically in an oil bath at 65°C for 1 hour. After the reaction is complete, add acid to adjust the pH to neutral (pH=7±1), let stand at 25°C for 10 minutes, make up to volume, and filter to obtain the treated solution T (a hydrolysate of *Centella asiatica*, i.e., the *Centella asiatica* extract described in this invention).

[0108] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0109] Detection results: See Tables 1-4. In this embodiment, T satisfies A.M / A B <0.01 and A K / A B <0.01; the concentration of cypermethrin I increased from 0.39 mg / mL to 0.44 mg / mL (IB=12.8%); DM=100%.

[0110] III. Comparative Example Comparative Example 1 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0111] S2: Add NaOH solution to the aqueous extract obtained in step S1 to adjust the pH of the system to 8. Stir magnetically in an oil bath at 95°C for 1 hour. After the reaction is complete, add acid to adjust the pH to neutral (pH=7±1), let stand at 25°C for 30 minutes, make up to volume, and filter to obtain the treated solution T.

[0112] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0113] Test results: See Tables 1-4. In this comparative example, A M / A B = 0.14 (>0.1), insufficient deacylation; the concentration of cypermethrin I decreased from 0.39 mg / mL to 0.34 mg / mL (IB=-12.8%); AK was not detected.

[0114] Analysis: In this comparative example, using pH 8, 95℃, and 1 hour, the degradation rate of 6''-malonyl cypermethrin I was only 19%, and the content of cypermethrin I decreased rather than increased, both significantly lower than in Example 1. This indicates that under excessively low pH conditions, even with high temperatures, the hydrolysis efficiency of malonyl ester bonds remains low, preventing complete conversion. Furthermore, high temperatures may trigger other degradation / side reactions, leading to a decrease in cypermethrin I.

[0115] Comparative Example 2 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0116] S2: The aqueous extract obtained in step S1 is not adjusted for pH (the original solution has a pH of approximately 5-6). The mixture is then reacted in an oil bath at 95°C with magnetic stirring for 2 hours. After the reaction is complete, the mixture is cooled and filtered to obtain the treated solution T (heat-treated solution).

[0117] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0118] Test results: The results are shown in Tables 1-4. In this comparative example, A M / A B = 0.14 (>0.1), insufficient deacylation; the concentration of cypermethrin I decreased from 0.39 mg / mL to 0.32 mg / mL (IB=-17.9%); A K Not detected.

[0119] Analysis: Under simple heat treatment conditions, the thermal decomposition efficiency of malonyl ester bonds is much lower than that under alkaline hydrolysis. A M / A B Exceeding 0.1. Simultaneously, high temperatures may trigger other degradation / side reactions, leading to a decrease in cypermethrin I.

[0120] Comparative Example 3 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0121] S2: Add NaOH solution to the aqueous extract obtained in step S1 to adjust the pH of the system to 14. Stir the reaction magnetically in an oil bath at 65°C for 2 hours. After the reaction is complete, adjust the pH to neutral (pH=7±1), filter, and obtain the treated solution T.

[0122] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0123] Test results: See Tables 1-4. In this comparative example, A M / A B <0.01 (acyl group desaturated), but A K / A B = 0.16 (>0.15), indicating the presence of free kaempferol; the concentration of kaempferol I decreased from 0.34 mg / mL to 0.15 mg / mL (IB=-55.9%).

[0124] Analysis: Under strongly alkaline conditions, although 6''-malonyl kaempferol I is completely degraded, the high pH causes significant breakage of glycosidic bonds, resulting in a substantial increase in the content of free kaempferol. K / A B More than 0.15.

[0125] Comparative Example 4 S1: Cut the Bai Rui herb into 5 cm long segments, add water with a pH of 7.0, and the ratio of herb to water is 1:14 (g / mL). Heat and reflux twice for 2 hours each time, filter, combine the filtrates to obtain the water extract (control sample W).

[0126] S2: Add 1 mol / L HCl solution to the aqueous extract obtained in step S1 to adjust the pH of the system to <3. Stir magnetically in an oil bath at 90℃ for 1 hour. After the reaction is complete, adjust the pH to neutral (pH=7±1), bring the volume to a final volume, and filter to obtain the treated solution T (acid hydrolysate).

[0127] S3: Determine W and T by HPLC according to the aforementioned detection method and calculate the ratio and rate of change.

[0128] Test results: The results are shown in Tables 1-4. In this comparative example, A M / A B = 0.22 and A K / A B = 0.18 (none of which are met), the concentration of cypermethrin I decreased from 0.34 mg / mL to 0.11 mg / mL (IB=-67.6%).

[0129] Analysis: Under acidic conditions, the degradation rate of 6''-malonyl kaempferol I is extremely low, and due to the excessive acidity, the glycosidic bonds undergo significant breakage, resulting in a substantial increase in the content of free kaempferol. K / A B More than 0.15.

[0130] IV. Summary of Results Table 1. HPLC peak area detection results

[0131] Note: 0 indicates not detected (S / N<3).

[0132] Table 2 Calculation results of HPLC peak area ratios (based on the treatment solution T)

[0133] Note: 0 indicates not detected (S / N<3).

[0134] Table 3. Results of determination of cypermethrin I content (external standard method)

[0135] Note: I B=[(Concentration of treatment solution T - Concentration of aqueous extract W) / Concentration of aqueous extract W] × 100%; the concentration is the concentration of gentianin I in the original treatment solution T prepared according to the method of the present invention (unconcentrated or diluted), and is calculated according to the dilution factor after dilution of the test sample. The batches of gentian herbs used in Comparative Examples 3–4 are different from those in Examples 1–2, therefore the initial content of aqueous extract W is different. For different batches of gentian herbs, the absolute peak area and absolute concentration of related compounds may differ; however, under the same detection system, A M / A B and A K / A B As a relative composition indicator, it can still be used to characterize the compositional features of the extract obtained by selective deacylation of the present invention.

[0136] Table 46. Conversion results of ''-malonyl pachymectin I

[0137] Note: D M =[(A M(水提液W) - A M(处理液T) ) / A M(水提液W) ] × 100% V. Results Analysis The following conclusions can be drawn from the above examples and comparative results: (1) Effects within the condition window of the present invention: After treatment at pH 11.0–13.3 and temperature 25–65°C, Examples 1–4 all significantly reduced the residual level of 6''-malonyl cypermethrin I and increased the content of cypermethrin I compared to before treatment. Specifically, the reduction rate of 6''-malonyl cypermethrin I in Examples 1, 2, and 4 reached 100%, while the reduction rate in Example 3 was 59.8%; at the same time, the content of cypermethrin I in Examples 1–4 increased by 10.3%–17.9%. Among them, Example 1 (pH 12.9, 55°C, 30 min) showed the best overall effect, with the content of cypermethrin I increasing by 17.9%.

[0138] (2) When pH is too low or heat treatment is only performed: insufficient acyl removal makes it difficult to achieve the target ratio: In Comparative Example 1, under the conditions of pH 8, 95℃, and reaction time of 1 h, the reduction rate of 6''-malonyl cypermethrin I was only 19%, and A M / A B This value is still higher than the threshold specified in this invention, indicating that even with increased temperature, it is difficult to achieve efficient hydrolysis of malonyl bonds at low pH conditions. Comparative Example 2, which used heat treatment only (95°C, 2 h), also showed A M / A BThe levels are still higher than the threshold specified in this invention, indicating that simply relying on high-temperature long-term treatment is insufficient to achieve the required degree of deacylation; at the same time, the content of cypermethrin I decreased, suggesting that degradation or other side reactions may occur under these conditions, which is not conducive to the retention of the active ingredient.

[0139] (3) In strong bases or strong acids: although it can promote the removal of acyl groups, the selectivity becomes poor (A K (Increase / Generation of Aglycone): In Comparative Example 3, after treatment in a strongly alkaline environment (pH 14), the reduction rate of 6''-malonyl kaempferol I reached 100%, indicating that strong alkali can significantly promote the hydrolysis of malonyl ester bonds; however, free kaempferol was also generated, leading to A... K / A B Exceeding the threshold specified in this invention indicates decreased selectivity and a risk of glycosidic bond breakage under strongly alkaline conditions. Comparative Example 4, after treatment in a strongly acidic environment (pH < 3), A... K / A B Similarly, the content of cypermethrin I also exceeded the threshold specified in this invention, and was accompanied by a significant decrease, indicating that strong acid conditions can also trigger side reactions that are not conducive to the retention of the target flavonoid glycosides and produce aglycones.

[0140] Based on the above results, it can be concluded that only pursuing sufficient acyl removal (e.g., making A...) M / A B (Very low) levels are insufficient to obtain the target extract; it is also necessary to simultaneously control A K / A B To avoid aglycone formation. Therefore, the parameter range defined in this invention (e.g., pH 11–13.5, temperature 25–65°C) can control the level of free kaempferol while achieving effective hydrolysis of malonyl ester bonds, thereby balancing the selective requirements of "sufficient acyl removal" and "glycosidic bond retention".

[0141] For different batches of medicinal materials, different extraction concentrations, different equipment scales, or different heat transfer and stirring conditions, those skilled in the art can perform routine screening within the pH, temperature, and time ranges described in this specification, and use the aforementioned A M / A B and A K / A B As an endpoint determination criterion, processing conditions that can balance the degree of deacylation and the preservation of glycosidic bonds are identified. These criteria are used to assess the degree of selective deacylation achieved under different conditions, rather than using a single criterion change under a single condition to represent the overall technical effect of the invention.

[0142] VI. Formulation Examples The deacylation reaction described in this invention can be completed in a conventional stirred reactor or jacketed reactor. The alkaline solution used is readily available, the process conditions are controllable, and it is easy to connect with existing Centella asiatica water extraction production lines.

[0143] The obtained *Lysimachia christinae* extract can be prepared into dosage forms such as granules, tablets, capsules, pellets, or powders according to conventional methods in the art. Taking granules as an example, the *Lysimachia christinae* extract is concentrated under reduced pressure to a thick paste, excipients such as dextrin and sucrose are added, followed by granulation, drying, and sizing. For tablets and capsules, the alkaline hydrolysate can be spray-dried, conventional excipients added, and tableted or encapsulated according to conventional processes. The fingerprint of the obtained formulation can be verified using the aforementioned HPLC method.

[0144] Formulation Example 1: Granules Take 1000 mL of the *Centella asiatica* extract solution prepared in Example 1, and concentrate it under reduced pressure to a thick paste with a relative density of 1.25–1.30 at 60°C, yielding approximately 120 g of the paste. Add 80 g of dextrin and 40 g of sucrose to the paste and mix thoroughly. Add 75% ethanol (by volume) as a wetting agent until a uniform soft mass is formed. Granulate the mass through a 14-mesh sieve, dry it at 60°C for 2 hours, and then granulate it through a 12-mesh sieve to obtain approximately 230 g of *Centella asiatica* granules. Package the granules into 5 g bags.

[0145] Formulation Example 2: Tablets Take 1000 mL of the *Centella asiatica* extract solution prepared in Example 1, and spray dry it to obtain approximately 50 g of dried powder. Add 30 g of starch, 15 g of microcrystalline cellulose, and 0.5 g of magnesium stearate to the dried powder, mix well, and compress into tablets, each weighing 0.3 g, to obtain approximately 320 *Centella asiatica* tablets.

[0146] Formulation Example 3: Capsules Take 1000 mL of the *Centella asiatica* extract solution prepared in Example 1, and spray dry it to obtain approximately 50 g of dried powder. Add 25 g of starch to the dried powder, mix well, and then fill it into No. 0 gelatin capsules, with each capsule containing 0.25 g, to obtain approximately 300 *Centella asiatica* capsules.

[0147] The above description is merely a preferred embodiment of this application and is not intended to limit the scope of this application. Although this application has been described in detail with reference to the above embodiments, those skilled in the art can still make various modifications or equivalent substitutions of some technical features after reading this description. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application should be considered to fall within the protection scope of this application.

Claims

1. A herb extract, characterized in that, Peak area A of 6''-malonyl cypermethrin I M Peak area A of cypermethrin I B Peak area A of free kaempferol K satisfy: (i) A M / A B <0.1; and (ii)A K / A B ≤ 0.15; A M A B and A K The determination was performed under the following reversed-phase high-performance liquid chromatography conditions: the chromatographic column was an octadecylsilane-bonded silica column; Mobile phase A is acetonitrile, mobile phase B is 0.2% formic acid aqueous solution, and gradient elution is used; The gradient elution program is as follows: 0 to 15 minutes, 15% mobile phase A; 15 to 17 minutes, mobile phase A increases from 15% to 20%; 17 to 32 minutes, 20% mobile phase A; 32 to 42 minutes, mobile phase A increases from 20% to 100%. The detection wavelength was 365 nm; the column temperature was 30℃; and the flow rate was 0.8 mL / min.

2. The Centella asiatica extract according to claim 1, characterized in that, Under the conditions of reversed-phase high-performance liquid chromatography, the characteristic peak of free kaempferol was not detected (S / N<3). Preferably, under the reversed-phase high-performance liquid chromatography conditions, A M / A B ≤ 0.06, A is preferred M / A B ≤ 0.01; Preferably, when measured under the reversed-phase high-performance liquid chromatography conditions, the chromatographic peak of 6''-malonyl cypermethrin I is below the detection limit; Preferably, when the external standard method is used for determination, the concentration of gentianin I in the *Centella asiatica* extract is not less than 0.40 mg / mL, where the concentration refers to the concentration of the original alkaline hydrolysate before concentration or dilution.

3. The Centella asiatica extract according to claim 1 or 2, characterized in that, The extract of Centella asiatica can be obtained by alkaline hydrolysis of Centella asiatica aqueous extract. The alkaline hydrolysis includes adjusting the pH of the aqueous extract to 11–13.5 and maintaining it at 25–65°C for 20–60 minutes. Preferably, the alkaline hydrolysis treatment conditions are: pH 12.5–13, temperature 53–58°C, and time 25–35 minutes; Preferably, the alkaline solution used in the alkaline hydrolysis treatment is selected from sodium hydroxide solution or potassium hydroxide solution, and the concentration of the alkaline solution is 0.5–2.5 mol / L.

4. The Centella asiatica extract according to claim 3, characterized in that, The aqueous extract of Centella asiatica is prepared by extracting Centella asiatica by decoction or reflux extraction.

5. A method for preparing the Centella asiatica extract according to claim 1, characterized in that, include: (a) Extract the herb *Cynanchum paniculatum* with water to obtain a water extract of *Cynanchum paniculatum*; (b) Add an alkaline solution to the aqueous extract of Centella asiatica to adjust the pH to 11–13.5 and carry out the hydrolysis reaction at 25–65°C for 20–60 minutes; (c) After the hydrolysis reaction is completed, the mixture is cooled and separated to obtain the extract of Centella asiatica.

6. The method according to claim 5, characterized in that, In step (a), the ratio of medicinal herbs to water is 1:5–15 (g / mL), and the extraction is performed by reflux 2–4 times, each time for 1–2 hours. Preferably, step (c) includes adjusting the reaction solution to pH 6–8 and removing insoluble matter by filtration or centrifugation.

7. Use of the Centella asiatica extract according to any one of claims 1 to 4 in the preparation of a medicament for anti-inflammatory purposes.

8. Use of the Centella asiatica extract according to any one of claims 1 to 4 in the preparation of health food with antioxidant function.

9. Use of the herb extract of any one of claims 1 to 4 in the preparation of herb granules, tablets or capsules.

10. A preparation of Centella asiatica, characterized in that, The preparation contains the extract of Centella asiatica as any one of claims 1 to 4 as an active ingredient, and pharmaceutically acceptable excipients; the dosage form of the preparation is selected from granules, tablets, capsules, pellets or powders.

Images