Arbutin derivative 6-O-Caffeoylbutin as well as preparation method and application thereof

Abstract

The invention discloses an arbutin derivative 6-O-Caffeoylbutin as well as a preparation method and application of the arbutin derivative 6-O-Caffeoylbutin. The structural formula of a 6-O-Caffeoylbutin compound is as shown in formula (I). The invention also discloses the application of the arbutin derivative (6-O-Caffeoylbutin) disclosed by the invention in preparation of an antioxidant preparation. According to the invention, the 6-O-Caffeoylbutin extracted for the first time shows excellent antioxidant activity, the ABTB free radical scavenging capacity of the 6-O-Caffeoylbutin is higher than that of ascorbic acid and beta-arbutin, and a material basis is provided for developing novel antioxidants.

Description

Technical Field

[0001] This invention relates to the technical fields of natural product chemistry and phytochemistry, specifically to an arbutin derivative (6- O -Caffeoylarbutin) and its preparation methods and applications. Background Technology

[0002] Yunnan golden camellia ( Camellia fascicularis (This is a species belonging to the genus Camellia in the family Theaceae.) Camellia Golden camellia is a deciduous shrub, famous for its golden petals. It is not only a rare species but also has a centuries-old history of medicinal and culinary use in China, used to treat various ailments such as dysentery, hematochezia, tumors, and hypertension. Yunnan golden camellia is rich in amino acids, minerals, and bioactive components such as tea polyphenols, saponins, flavonoids, and tea polysaccharides. Pharmacological and clinical trials have proven its various pharmacological effects, including antioxidant, antitumor, antibacterial, lipid-lowering, blood sugar-lowering, and cholesterol-lowering properties. Despite the numerous potential health benefits of Yunnan golden camellia, the Yunnan golden camellia, a species endemic to Yunnan, is relatively rare. Camellia fascicularis Research on *Camellia yunnanensis* started relatively late, but its potential for discovering functional active ingredients is enormous. In particular, in the aqueous phase, *Camellia yunnanensis* exhibits superior antioxidant activity compared to other organic phases, but the specific components remain unclear. Currently, there is a lack of 6- O -Caffeoylarbutin compounds, their preparation methods, and applications. Summary of the Invention

[0003] The purpose of this invention is to provide a 6- O -Caffeoylarbutin compounds, their preparation methods, and applications. To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: The present invention Firstly, this application provides a 6- O -Caffeoylarbutin compound. Secondly, this application provides a 6- O Preparation method of -Caffeoylarbutin compound. Thirdly, this application provides an aqueous extract of Camellia chrysantha var. yunnanensis. Fourthly, this application provides a 6- O Application of Caffeoylarbutin compounds in the preparation of antioxidant agents. Fifthly, this application provides a solution containing 6- OCompositions of -Caffeoylarbutin, compositions used for antioxidant purposes. Sixthly, this application provides a method for determining 6- O -Methods for assessing the antioxidant activity of Caffeoylarbutin using ABTS + Free radical scavenging rate was used as a test indicator.

[0004] The first aspect of this application provides 6- O -Caffeoylarbutin compound, 6- O The structural formula of the Caffeoylarbutin compound is shown in formula (I): (I).

[0005] The second aspect of this application provides 6- O The preparation method of the -Caffeoylarbutin compound includes the following steps: a. Take a dry sample of Yunnan golden flower tea leaves and grind it to 40-80 mesh; b. Use 95% industrial methanol to perform condensation reflux extraction 3 times at 40-60 ℃, each time for 1-3 hours; c. Combine the extracts and recover methanol using a rotary evaporator at low pressure and 40-60 °C to obtain a methanol extract. d. Mix the methanol extract with distilled water and extract with petroleum ether and ethyl acetate in sequence; e. After recovering the solvent, the petroleum ether fraction extract and the ethyl acetate fraction extract are obtained. The remaining aqueous fraction is concentrated at high temperature and low pressure to obtain the Yunnan golden camellia aqueous extract. f. The sample was loaded onto the column using macroporous resin D101 and eluted with a water / methanol gradient to obtain a 40% methanol aqueous extract; g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 fractions Fr. (AJ); h. The monomeric compound 6- was purified by silica gel column chromatography and preparative high-performance liquid chromatography (PHPLC). O -Caffeoylarbutin. Furthermore, in step (c), the methanol used is industrial grade methanol; in step (d), both petroleum ether and ethyl acetate used are industrial grade; the temperature of the petroleum ether is 60-90 ℃. Further, in step (f), water:methanol gradient elution is performed with a water to methanol volume ratio of 100:0 – 0:100; in step (g), gradient elution is performed in gel column chromatography with a water to methanol volume ratio of 80:20 – 0:100; in step (h), 200-300 mesh silica gel is used. The third aspect of this application provides an aqueous extract of Camellia chrysantha var. yunnanensis, obtained by a method. The fourth aspect of this application provides a 6- O Application of Caffeoylarbutin compound in the preparation of antioxidant agents. The fifth aspect of this application provides a product containing 6- O A composition of (-Caffeoylarbutin), the composition is used for antioxidation. The sixth aspect of this application provides a method for determining 6- O -Methods for assessing the antioxidant activity of Caffeoylarbutin using ABTS + Free radical scavenging rate was used as a test indicator. Furthermore, in the determination method, ABTS + The formula for calculating the free radical scavenging rate is: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%. Beneficial effects: The 6- extracted for the first time in this invention O -Caffeoylarbutin exhibits superior antioxidant activity, particularly in scavenging ABTB. + Its free radical scavenging ability is stronger than that of ascorbic acid and β-arbutin, providing a material basis for the development of novel antioxidants. Compared with the prior art, the present invention has the following advantages: (1) The 6- of the present invention O -Caffeoylarbutin, an arbutin derivative, is the most abundant caffeoyl phenolic compound in *Tea lycopersicum*, exhibiting significant antioxidant activity and free radical scavenging ability. However, 6- O No studies have been reported on Caffeoylarbutin in Camellia species, and no method has been established for its isolation and purification in Camellia yunnanensis. (2) High-efficiency extraction and purification of the present invention: The method of the present invention effectively extracts and purifies 6- from Yunnan golden flower tea leaves through a series of extraction, extraction and chromatography techniques. O -Caffeoylarbutin improved the purity and recovery rate of the target compound. In-depth pharmacological studies: High-purity 6-Caffeoylarbutin obtained through the method of this invention... O Caffeoylarbutin allows for more accurate research into its pharmacological effects, including anti-tumor, antibacterial, lipid-lowering, blood sugar-lowering, and cholesterol-lowering properties, providing a scientific basis for the medicinal value of Camellia chrysantha. (3) Promote the development and utilization of Yunnan golden camellia resources: This invention provides a theoretical basis and technical support for the in-depth research and development of Yunnan golden camellia, a precious resource, and helps to promote its application in the fields of medicine and health food. (4) Environmentally friendly: The solvents and materials used in the extraction and purification methods of this invention are all industrial grade, and the process is easy to control and repeat, reducing the impact on the environment and meeting the requirements of green chemistry and sustainable development.

[0006] (5) Economic benefits: The method of this invention can be used to extract and purify 6- on a large scale. O -Caffeoylarbutin provides high-value-added natural active ingredients for related industries, resulting in significant economic benefits. Attached Figure Description

[0007] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 Compound 6 of the present invention O -Flowchart of the isolation and purification process of Caffeoylarbutin; Figure 2 Compound 6 of the present invention O - Semi-preparative liquid phase separation diagram of Caffeoylarbutin; Figure 3 Compound 6 of the present invention O -Caffeoylarbutin 1 H NMR and 13 C NMR spectrum. Detailed Implementation

[0008] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship. In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple. It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a well-known unit of mass in the chemical industry, such as µg, mg, g, or kg. The first aspect of the embodiments of this application provides a 6- O -Caffeoylarbutin compound, 6- O The structural formula of the Caffeoylarbutin compound is shown in formula (I): (I). A second aspect of the embodiments of this application provides a 6- O The preparation method of the -Caffeoylarbutin compound includes the following steps: a. Take a dry sample of Yunnan golden flower tea leaves and grind it to 40-80 mesh; b. Use 95% industrial methanol to perform condensation reflux extraction 3 times at 40-60 ℃, each time for 1-3 hours; c. Combine the extracts and recover methanol using a rotary evaporator at low pressure and 40-60 °C to obtain a methanol extract. d. Mix the methanol extract with distilled water and extract with petroleum ether and ethyl acetate in sequence; e. After recovering the solvent, the petroleum ether fraction extract and the ethyl acetate fraction extract are obtained. The remaining aqueous fraction is concentrated at high temperature and low pressure to obtain the Yunnan golden camellia aqueous extract. f. The sample was loaded onto the column using macroporous resin D101 and eluted with a water / methanol gradient to obtain a 40% methanol aqueous extract; g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 fractions Fr. (AJ); h. The monomeric compound 6- was obtained by purification by silica gel column chromatography and semi-preparative high-performance liquid chromatography (PHPLC). O -Caffeoylarbutin. In some embodiments, in step (c), the methanol used is industrial grade methanol; in step (d), both petroleum ether and ethyl acetate used are industrial grade; and the temperature of the petroleum ether is 60-90 °C. In some embodiments, in step (f), the volume ratio of water to methanol is 100:0 - 0:100; in step (g), in gel column chromatography, the volume ratio of water to methanol is 80:20 - 0:100; and in step (h), the silica gel used is 200-300 mesh. The third aspect of this application provides an aqueous extract of Camellia chrysantha var. yunnanensis, obtained by a method. The fourth aspect of this application provides a 6- O Application of Caffeoylarbutin compound in the preparation of antioxidant agents. A fifth aspect of this application provides a 6- [structure / method] comprising the 6- [structure / method] of claim 1. O A composition of -Caffeoylarbutin, the composition being used for antioxidant purposes. A sixth aspect of this application provides a method for determining the 6- as described in claim 1. O -Methods for assessing the antioxidant activity of Caffeoylarbutin using ABTS + Free radical scavenging rate was used as a test indicator. In some embodiments, the formula for calculating the ABTS free radical scavenging rate in the assay method is: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%. Example 1 A 6- provided by the present invention O -Caffeoylarbutin compound, 6- O The structural formula of the Caffeoylarbutin compound is shown in formula (I): (I).

[0009] Example 2 A 6- O The preparation method of the -Caffeoylarbutin compound includes the following steps: a. Take a dry sample of Yunnan golden flower tea leaves and grind it to 40 mesh; b. Use 95% industrial methanol to perform reflux extraction at 60 °C three times, each time for 1 hour; c. Combine the extracts and recover methanol using a rotary evaporator at 40 °C and low pressure to obtain a methanol extract; the methanol used is industrial grade methanol. d. Mix the methanol extract with distilled water and extract with petroleum ether and ethyl acetate in sequence; both petroleum ether and ethyl acetate used are industrial grade; the temperature of the petroleum ether is 60 ℃. e. After recovering the solvent, the petroleum ether fraction extract and the ethyl acetate fraction extract are obtained. The remaining aqueous fraction is concentrated at high temperature and low pressure to obtain the Yunnan golden camellia aqueous extract. f. The sample was loaded onto a column using macroporous resin D101 and eluted with a water / methanol gradient to obtain a 40% methanol aqueous extract; the volume ratio of water to methanol was 100:0 - 0:100. g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 fractions Fr. (AJ); the volume ratio of water to methanol in the gel column chromatography was 80:20 - 0:100. h. The monomeric compound 6- was obtained by purification by silica gel column chromatography and semi-preparative high-performance liquid chromatography (PHPLC). O -Caffeoylarbutin. The silica gel used is 200 mesh. The present invention relates to an aqueous extract of Camellia chrysantha from Yunnan, obtained by a method. Example 3 The difference between Example 3 and Example 2 is that: a 6- O The preparation method of the -Caffeoylarbutin compound includes the following steps: In step a, take a dry sample of Yunnan golden flower tea leaves and grind it to 60 mesh; In step b, 95% industrial methanol was used for condensation reflux extraction three times at 40 °C, each time for 2 hours; In step c, the extracts are combined, and methanol is recovered using a rotary evaporator at 60 °C and low pressure to obtain a methanol extract; the methanol used is industrial grade methanol. In step d, the methanol extract is mixed with distilled water and extracted sequentially with petroleum ether and ethyl acetate; both petroleum ether and ethyl acetate used are industrial grade; the temperature of the petroleum ether is 80 °C. In step f, macroporous resin D101 is used to mix the sample and load it onto the column, and water / methanol gradient elution is used to obtain a 40% methanol aqueous extract; water:methanol gradient elution, the volume ratio of water to methanol is 100:0 - 0:100. In step g, elution was performed using a Sephadex LH-20 gel column to obtain 10 fractions Fr. (AJ); in gel column chromatography, gradient elution was achieved with a water to methanol volume ratio of 80:20 - 0:100. In step h, the monomeric compound 6- was purified by silica gel column chromatography and semi-preparative high-performance liquid chromatography (PHPLC). O -Caffeoylarbutin. The silica gel used is 300 mesh. Example 4 The difference between Example 4 and Example 2 is that: a 6- O The preparation method of the -Caffeoylarbutin compound includes the following steps: In step a, take a dry sample of Yunnan golden flower tea leaves and pulverize it to 80 mesh; In step b, 95% industrial methanol was used for condensation reflux extraction three times at 40 °C, each time for 3 hours. In step c, the extracts are combined, and methanol is recovered using a rotary evaporator at 50 °C and low pressure to obtain a methanol extract; the methanol used is industrial grade methanol. In step d, the methanol extract is mixed with distilled water and extracted sequentially with petroleum ether and ethyl acetate; both petroleum ether and ethyl acetate used are industrial grade; the temperature of the petroleum ether is 90 °C. In step f, macroporous resin D101 is used to mix the sample and load it onto the column, followed by water / methanol gradient elution to obtain a 40% methanol aqueous extract; the volume ratio of water to methanol is 100:0 - 0:100. In step g, elution was performed using a Sephadex LH-20 gel column to obtain 10 fractions Fr. (AJ); the volume ratio of water to methanol in the gel column chromatography was 80:20 - 0:100. In step h, the monomeric compound 6- was purified by silica gel column chromatography and semi-preparative high-performance liquid chromatography (PHPLC). O -Caffeoylarbutin. The silica gel used is 200 mesh. Example 5 A highly active 6- O - Application of phenolic compounds such as Caffeoylarbutin in the preparation of antioxidant agents. A method of the present invention comprising the 6- as described in claim 1 OA composition of -Caffeoylarbutin, the composition being used for antioxidant purposes. The present invention provides a method for determining the 6- as described in claim 1. O- Methods for assessing the antioxidant activity of caffeoylarbutin using ABTS + Free radical scavenging rate is used as a test indicator. In the determination method, ABTS... + The formula for calculating the free radical scavenging rate is: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%. Experimental Example 1 1. Instruments and Materials The following instruments were used in the column chromatography process: Bruker AV 500 MHz nuclear magnetic resonance spectrometer (Bruker GmbH, Germany), XEVO G2-XS Q-TOF high-resolution mass spectrometer (Waters Inc., USA), NP7000 semi-preparative liquid chromatography system (Jiangsu Hanbang Technology Co., Ltd., China), AX224ZH\E electronic balance (Ohaus Instruments (Changzhou) Co., Ltd., China), 101-2ES electric heating drying oven (Beijing Yongguangming Medical Instrument Co., Ltd., China), N-1300 rotary evaporator and CA-111 cold trap (Shanghai Ailang Instrument Co., Ltd., China), SHZ-DⅢ circulating water vacuum pump (Gongyi Yuhua Instrument Co., Ltd., China), and ZF-7 three-way ultraviolet analyzer (Shanghai Jiapeng Technology Co., Ltd., China). All reagents used in the column chromatography process were industrial grade. The specimen of *Camellia yunnanensis* (52860), identified by taxonomist Min Tianlu, is preserved in the herbarium of the Kunming Institute of Botany, Chinese Academy of Sciences. The *Camellia yunnanensis* tea leaves used in this experiment were obtained in December 2019 in the Daweishan Nature Reserve, Hekou County, Yunnan Province, China, and identified as *Camellia yunnanensis* by Professor Xiang Jianying, a taxonomist from Southwest Forestry University. Camellia fascicularis ) 。 2 Extraction and Separation 10.7 kg of dried *Camellia yunnanensis* tea leaves were pulverized to 40-80 mesh and extracted three times with 95% industrial methanol under reflux at 40-60 °C for 1-3 hours each time. The extracts were combined, and the industrial methanol was recovered under low pressure at 40-60 °C using a rotary evaporator to obtain 868.3 g of *Camellia yunnanensis* methanol extract. 5 L of distilled water was added and thoroughly mixed, followed by extraction with petroleum ether (60-90 °C) and ethyl acetate, respectively. After solvent recovery, 347.2 g of petroleum ether extract and 177.8 g of ethyl acetate extract were obtained. The remaining aqueous phase was concentrated under high temperature and low pressure to obtain 115.6 g of *Camellia yunnanensis* aqueous extract. 110.0 g of the extract was mixed with 170.0 g of macroporous resin D101 and loaded onto a column at V... 水 / 甲醇Elution with a gradient of 1:0 - 0:1, yielding 30.0 g of extract in 40% methanol and water. The extract was then purified using a Sephadex LH-20 gel column (V...). 水 / 甲醇 The mixture was eluted with a ratio of 80:20 - 0:100 to obtain 10 fractions Fr. (AJ). Fr. C (8.0 g) 12 g silica gel (200-300 mesh) as a sample for silica gel column chromatography, V 氯仿：甲醇 =20:1 - 1:1 gradient elution, TLC detection combined with the same fractions yielded 4 fractions Fr. (CA - CD), Fr. CA (3.9 g) 6.0 g silica gel (200-300 mesh) as a sample for silica gel column chromatography, V 氯仿：甲醇：水 Gradient elution of 8:2:0.2 - 6:4:1 was performed, and TLC analysis was conducted to combine identical fractions to obtain four fractions: Fr. (CAA - CAD). Fr. CAA (409 mg) was added to 1.0 g silica gel (200-300 mesh) for silica gel column chromatography. 氯仿：甲醇 A gradient elution of 20:1 to 1:1 was performed, and TLC analysis was used to combine identical fractions to obtain seven fractions Fr. (CAA1-CAA7). Fr. CAA2 was finally purified by semi-preparative high-performance liquid chromatography (PHPLC) to obtain monomer compound 1 (see separation and purification procedure). Figure 1 ). Figure 1 This is a flowchart illustrating the separation process of compound 1 of the present invention; 3. Structural Analysis 6- O -Caffeoylarbutin (1): Amorphous powder, HR–ESI–MS m / z 457.1180 [M + Na] + The molecular formula is C 21 H 22 O 10 . 1 H NMR (500 MHz, Methanol- d 4) δ H 7.54 (1H, d, J = 15.8 Hz, Hb), 7.02 (1H, d, J = 2.1 Hz, H-2), 6.91 (3H, d, J = 8.9 Hz, H-6, 2'', 6''), 6.76 (1H,d, J = 8.1 Hz, H-5), 6.62 (2H, d, J= 8.9 Hz, H-3'', 5''), 6.25 (1H, d, J =15.9 Hz, Ha), 4.69 (1H, d, J = 7.1 Hz, H-1'), 4.49 (1H, d, J = 11.9 Hz, H-6'b), 4.31 (1H, dd, J = 11.9, 6.6 Hz, H-6'a), 3.65 – 3.58 (1H, m, H-5'), 3.44 –3.36 (3H, m, H-2', 3', 4'). 13 C NMR (125 MHz, Methanol- d 4) δ C 169.3 (C=O), 154.2 (C-1''), 152.7 (C-4''), 150.0 (C-3), 147.6 (C-7b), 147.2 (C-4), 128.0 (C-1), 123.5 (C-6), 119.9 (C-2'', 6''), 116.9 (C-3'', 5''), 116.8 (C-5), 115.4 (C-2), 115.1 (Ca), 104.0 (C-1'), 78.1 (C-3'), 75.8 (C-2'), 75.3 (C-5'), 72.1 (C-4'), 64.9 (C-6'). Related spectra are shown below. Figure 3 As shown. 4 Antioxidant activity The experiment used 96-well plates, with a total capacity of 210 µL per well. Equal volumes of ABTS solution (7 mM) and potassium persulfate solution (5 mM) were mixed thoroughly and reacted in the dark at room temperature for 12 h to obtain an ABTS radical cation stock solution. The mixture was then diluted with anhydrous methanol to achieve an absorbance of 0.7 ± 0.02 at 734 nm. Next, 180 µL of ABTS working solution was added to each well, followed by 30 µL of sample at different concentrations (0.5, 0.1, 0.05, 0.01 mg / mL), dissolved, and diluted with DMSO. After thorough mixing, the samples were incubated in the dark at room temperature for 6 min. The absorbance of each well was then measured at 734 nm using a microplate reader, and the results were obtained from at least three independent experiments. Ascorbic acid and β -Ursolic acid was used as a positive control. The ABTS radical cation scavenging rate (%) of each test sample was calculated as follows (1): ABTS clearance rate (%) = [blank - (sample - control)] / blank × 100% (1) The ABTS test results are shown in Table 1: Table 1 "-" indicates that no experiment was conducted. Compound 1 at concentrations of 10-500 µg / mL, ABTS + It showed superior performance compared to the positive control (ascorbic acid and) in free radical scavenging experiments. β The study revealed significant activity of compound 1 (arbutin). This result suggests that compound 1 may possess superior efficacy in scavenging free radicals and resisting oxidative stress. This discovery provides a new candidate for antioxidants, contributing to a deeper understanding of their mechanisms of action and potential applications. Figure 2 This is a liquid phase separation diagram for the preparation of the present invention; Figure 3 For the present invention 1 HNMR and 13 C NMR spectrum. 5. Molecular docking for anti-inflammatory and hypoglycemic effects Molecular docking technology is suitable for simulating atomic-level interactions between small molecules and proteins. COX-2 (PDBID: 8ET0) and α The structure of the glucosidase (PDB ID: 3A4A) was obtained from the online protein database (https: / / www.rcsb.org / , accessed August 10, 2024), and the 3D structure of the ligand was generated using ChemBio3D Ultra 12.0. Ligands: COX-2 and... α Water molecules in the glucosidase crystal structure were virtually removed using PyMOL. Gasteiger charges and necessary hydrogen atoms were added using AutoDock. A semi-flexible docking mode was employed, with 20 docking attempts. Affinity (kcal / mol) represents the binding strength of two interactions; lower affinity values ​​indicate more stable binding between the ligand and receptor. Dexamethasone (DXMS) and DSEC were designated as positive controls for docking with anti-inflammatory drugs, while acarbose was selected as a control for docking with hypoglycemic drugs. PyMOL was used for visualization, and 2D plots were constructed and analyzed using Discovery Studio 2020 Client. Compound 1 underwent molecular docking with receptor proteins 8ET0 and 3A4A. 6. Research and Development of Yunnan Golden Camellia Flavored Beverage The optimal processing method for Yunnan golden camellia flavored beverage was determined using response surface methodology: 20 mL of Yunnan golden camellia extract (tea-to-water ratio 1:100), 1.8 mL / 100 mL of apple, 1.5 g of white sugar, 0.3 g of honey, 0.03 g of citric acid, 0.01 g of sodium citrate, 0.02 g of vitamin C, and 0.005 g of sodium bicarbonate (resulting in a slightly sweet and sour initial taste followed by a bitter aftertaste, effectively preserving the original flavor of Yunnan golden camellia tea). Under these conditions, the beverage exhibits a rich aroma characteristic of Yunnan golden camellia, a bright color, a harmonious and refreshing overall flavor, and a uniform texture, achieving a sensory score of 97.15. The product quality indicators are: pH 3.96, tea polyphenol content 512.74 ± 12.90 mg / kg, sugar content 7.2 °Brix, and soluble solids content ≥ 15%. The total bacterial count was ≤ 100 CFU / mL, and coliform bacteria and mold were not detected, meeting the national food safety standards. Antioxidant activity results showed that this beverage product has outstanding scavenging ability against DPPH and ABTS free radicals. Electronic nose detection revealed the presence of esters, aldehydes, and alcohols in the beverage, which give it its distinctive aroma. The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above-described experimental examples. The experimental examples and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope. The scope of protection of the present invention is defined by the appended claims, specification, and their equivalents.

Claims

1. An arbutin derivative 6- O -Caffeoylarbutin, characterized by: The arbutin derivative 6- O The structural formula of -Caffeoylarbutin is shown in equation (I): （I） 。 2. The arbutin derivative 6- according to claim 1 O The method for preparing -Caffeoylarbutin is characterized by Includes the following steps: a. Take a dry sample of Yunnan golden flower tea leaves and grind it to 40-80 mesh; b. Use 95% industrial methanol to perform condensation reflux extraction 3 times at 40-60 ℃, each time for 1-3 hours; c. Extraction: Combine the extracts and use a rotary evaporator at low pressure and 40-60 °C to recover methanol, obtaining a methanol extract; d. Extraction: The methanol extract was mixed with distilled water and extracted successively with petroleum ether and ethyl acetate; e. After recovering the solvent, the petroleum ether fraction extract and the ethyl acetate fraction extract are obtained. The remaining aqueous fraction is concentrated at high temperature and low pressure to obtain the Yunnan golden camellia aqueous extract. f. The sample was loaded onto the column using macroporous resin D101 and eluted with a water / methanol gradient to obtain a 40% methanol aqueous extract; g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 fractions Fr., fractions A to J; h. Compound 6- was purified by silica gel column chromatography and preparative high-performance liquid chromatography (PHPLC). O -Caffeoylarbutin.

3. The arbutin derivative 6- according to claim 2 O The method for preparing -Caffeoylarbutin is characterized by: In step (c), the methanol used is industrial grade methanol; in step (d), both petroleum ether and ethyl acetate used are industrial grade; the temperature of the petroleum ether is 60-90 ℃.

4. The arbutin derivative 6- according to claim 1 O The method for preparing -Caffeoylarbutin is characterized by: In step (f), water:methanol gradient elution is performed with a water to methanol volume ratio of 100:0 – 0:100; in step (g), gradient elution is performed in gel column chromatography with a water to methanol volume ratio of 80:20 – 0:100; in step (h), silica gel of 200-300 mesh is used.

5. A Yunnan golden camellia aqueous extract, characterized in that: Obtained by the method of any one of claims 2 to 4.

6. The arbutin derivative 6- according to claim 1 O Application of Caffeoylarbutin in the preparation of antioxidant agents.

7. A device comprising the 6- as described in claim 1 O The composition of -Caffeoylarbutin is characterized by: The composition is used for antioxidant purposes.

8. A method for determining the 6- as described in claim 1 O A method for detecting the antioxidant activity of Caffeoylarbutin, characterized by: Using ABTS + Free radical scavenging rate was used as a test indicator.

9. The method according to claim 8, characterized in that: In the aforementioned determination method, ABTS + The formula for calculating the free radical scavenging rate is: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%.

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