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 shown as a formula (I): # imgabs0. The invention also discloses 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 ability of the 6-O-Caffeoylbutin to remove ABTB < + > free radicals is stronger than that of ascorbic acid and beta-arbutin, and a material basis is provided for development of novel antioxidants.

Description

Technical Field

[0001] The invention relates to the technical field of natural product chemistry and phytochemistry, and in particular to an arbutin derivative (6-O-Caffeoylarbutin) and a preparation method and application thereof. Background Art

[0002] Yunnan Golden Camellia (Camellia fascicularis) is a deciduous shrub belonging to the genus Camellia in the family Theaceae. It is famous for its golden petals and is known as the "Giant Panda of the Plant Kingdom" and the "Queen of Tea". Golden Camellia is not only a rare species, but also has a history of being used as both medicine and food in China for hundreds of years. It has been used to treat dysentery, blood in the stool, tumors, hypertension and many other diseases. Yunnan Golden Camellia contains rich amino acids, minerals, and bioactive ingredients such as tea polyphenols, saponins, flavonoids, and tea polysaccharides. It has been proven by pharmacological and clinical experiments that it has multiple pharmacological effects such as antioxidant, anti-tumor, antibacterial, hypolipidemic, hypoglycemic, and cholesterol-lowering.

[0003] Despite the potential health benefits of Yunnan Golden Camellia, research on Yunnan Golden Camellia (Camellia fascicularis), a very small species unique to Yunnan, started relatively late, and the potential for exploring its functional active ingredients is huge. In particular, in the aqueous phase, Yunnan Golden Camellia showed antioxidant activity superior to other organic phases, but the specific components have not yet been identified.

[0004] Currently, there is a lack of a 6-O-Caffeoylarbutin compound with antioxidant activity and a preparation method and application thereof. Summary of the invention

[0005] The purpose of the present invention is to provide a 6-O-Caffeoylarbutin compound with antioxidant activity and a preparation method and application thereof.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present application provides a 6-O-Caffeoylarbutin compound.

[0008] In a second aspect, the present application provides a method for preparing a 6-O-Caffeoylarbutin compound.

[0009] In a third aspect, the present application provides an aqueous extract of Yunnan Camellia chrysantha.

[0010] In a fourth aspect, the present application provides a use of a 6-O-Caffeoylarbutin) compound in the preparation of an antioxidant preparation.

[0011] In a fifth aspect, the present application provides a composition containing 6-O-Caffeoylarbutin, which is used for anti-oxidation.

[0012] In a sixth aspect, the present application provides a method for determining the antioxidant activity of 6-O-Caffeoylarbutin using ABTS + Free radical scavenging rate was used as a test indicator.

[0013] The 6-O-Caffeoylarbutin compound provided in the first aspect of the present application has a structural formula as shown in formula (I):

[0014]

[0015] The second aspect of the present application provides a method for preparing a 6-O-Caffeoylarbutin compound, comprising the following steps:

[0016] a. Take the dried Yunnan Golden Flower tea leaves and crush them into 40-80 mesh;

[0017] b. Use 95% industrial methanol to perform condensation reflux extraction at 40-60°C for 3 times, each time for 1-3 hours;

[0018] c. Combine the extracts and use a rotary evaporator to recover methanol at 40-60°C under low pressure to obtain a methanol extract;

[0019] d. The methanol extract was mixed with distilled water and extracted with petroleum ether and ethyl acetate in turn;

[0020] e. After the solvent is recovered, a petroleum ether extract and an ethyl acetate extract are obtained, and the remaining aqueous phase is concentrated at high temperature and low pressure to obtain an aqueous extract of Yunnan Camellia chrysantha;

[0021] f. Use macroporous resin D101 to mix the sample and load it onto the column, and elute it with a water / methanol gradient to obtain a 40% methanol water extract;

[0022] g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 components Fr. (AJ);

[0023] h. Purification by silica gel column chromatography and preparative high performance liquid chromatography (PHPLC) gave a monomer compound, 6-O-Caffeoylarbutin.

[0024] Furthermore, in step (c), the methanol used is industrial grade methanol; in step (d), the petroleum ether and ethyl acetate used are both industrial grade; and the temperature of the petroleum ether is 60-90°C.

[0025] Furthermore, in step (f), water:methanol gradient elution is performed, and the volume ratio of water to methanol is 100:0-0:100; in step (g), in gel column chromatography, gradient elution is performed, and the volume ratio of water to methanol is 80:20-0:100; in step (h), the silica gel used is 200-300 mesh.

[0026] The third aspect of the present application provides an aqueous extract of Camellia chrysantha, which is obtained by a method.

[0027] A fourth aspect of the present application provides a use of a 6-O-Caffeoylarbutin compound in the preparation of an antioxidant preparation.

[0028] The fifth aspect of the present application provides a composition containing 6-O-Caffeoylarbutin, which is used for anti-oxidation.

[0029] The sixth aspect of the present application provides a method for determining the antioxidant activity of 6-O-Caffeoylarbutin using ABTS + Free radical scavenging rate was used as a test indicator.

[0030] Furthermore, in the determination method, ABTS + The free radical scavenging rate was calculated as follows: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%.

[0031] Beneficial effect: The 6-O-Caffeoylarbutin extracted for the first time in the present invention shows excellent antioxidant activity, which is effective in clearing ABTB. + Its free radical capacity is stronger than that of ascorbic acid and β-arbutin, which provides a material basis for the development of new antioxidants.

[0032] Compared with the prior art, the present invention has the following advantages:

[0033] (1) The 6-O-Caffeoylarbutin of the present invention is an arbutin derivative and is the phenolic compound with the highest content of caffeoyl in Camellia sinensis, and has significant antioxidant activity and the ability to scavenge free radicals. However, there has been no report on the study of 6-O-Caffeoylarbutin in Camellia genus plants, and a method for its separation and purification in Yunnan golden camellia has not been established.

[0034] (2) Efficient extraction and purification of the present invention: The method of the present invention effectively extracts and purifies 6-O-Caffeoylarbutin from Yunnan Golden Flower Tea leaves through a series of extraction, extraction and chromatography techniques, thereby improving the purity and recovery rate of the target compound. In-depth study of pharmacological effects: The high-purity 6-O-Caffeoylarbutin obtained by the method of the present invention can be used to more accurately study its pharmacological effects, including anti-tumor, antibacterial, hypolipidemic, hypoglycemic and cholesterol-lowering effects, providing a scientific basis for the medicinal value of Golden Flower Tea.

[0035] (3) Promoting the development and utilization of Yunnan Camellia chrysantha resources: The present invention provides a theoretical basis and technical support for the in-depth research and development of Yunnan Camellia chrysantha, a precious resource, and helps promote its application in the fields of medicine, health food, etc.

[0036] (4) Environmentally friendly: The solvents and materials used in the extraction and purification methods adopted by the present invention are all of industrial grade, and the process is easy to control and repeat, which reduces the impact on the environment and meets the requirements of green chemistry and sustainable development.

[0037] (5) Economic Benefits: The method of the present invention can be used to extract and purify 6-O-Caffeoylarbutin on a large scale, providing high value-added natural active ingredients for related industries, thereby achieving significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0039] Figure 1 This is a flow chart for separation and purification of the compound 6-O-Caffeoylarbutin of the present invention;

[0040] Figure 2 This is a semi-preparative liquid phase separation diagram of the compound 6-O-Caffeoylarbutin of the present invention;

[0041] Figure 3 The compound 6-O-Caffeoylarbutin of the present invention 1 H NMR and 13 C NMR spectrum. DETAILED DESCRIPTION

[0042] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0043] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0044] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0045] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and 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 the present application.

[0046] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0047] The weight of the relevant components mentioned in the embodiment description of the present application can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the embodiment description of the present application, it is within the scope disclosed in the embodiment description of the present application. Specifically, the mass described in the embodiment description of the present application can be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0048] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0049] In a first aspect, the present application provides a 6-O-Caffeoylarbutin compound, the structural formula of the 6-O-Caffeoylarbutin compound is shown in formula (I):

[0050]

[0051] A second aspect of the present application embodiment provides a method for preparing a 6-O-Caffeoylarbutin compound, comprising the following steps:

[0052] a. Take the dried Yunnan Golden Flower tea leaves and crush them into 40-80 mesh;

[0053] b. Use 95% industrial methanol to perform condensation reflux extraction at 40-60°C for 3 times, each time for 1-3 hours;

[0054] c. Combine the extracts and use a rotary evaporator to recover methanol at 40-60°C under low pressure to obtain a methanol extract;

[0055] d. The methanol extract was mixed with distilled water and extracted with petroleum ether and ethyl acetate in turn;

[0056] e. After the solvent is recovered, a petroleum ether extract and an ethyl acetate extract are obtained, and the remaining aqueous phase is concentrated at high temperature and low pressure to obtain an aqueous extract of Yunnan Camellia chrysantha;

[0057] f. Use macroporous resin D101 to mix the sample and load it onto the column, and elute it with a water / methanol gradient to obtain a 40% methanol water extract;

[0058] g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 components Fr. (AJ);

[0059] h. Purification by silica gel column chromatography and semi-preparative high performance liquid chromatography (PHPLC) gave a monomer compound, 6-O-Caffeoylarbutin.

[0060] In some embodiments, in step (c), the methanol used is industrial grade methanol; in step (d), the petroleum ether and ethyl acetate used are both industrial grade; and the temperature of the petroleum ether is 60-90°C.

[0061] 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; in step (h), the silica gel used is 200-300 mesh.

[0062] A third aspect of the embodiments of the present application provides an aqueous extract of Camellia chrysantha, which is obtained by a method.

[0063] A fourth aspect of the embodiments of the present application provides a use of a 6-O-Caffeoylarbutin compound in the preparation of an antioxidant preparation.

[0064] A fifth aspect of the embodiments of the present application provides a composition containing the 6-O-Caffeoylarbutin according to claim 1, wherein the composition is used for anti-oxidation.

[0065] In a sixth aspect, the present invention provides a method for determining the antioxidant activity of 6-O-Caffeoylarbutin according to claim 1, using ABTS + Free radical scavenging rate was used as a test indicator.

[0066] In some embodiments, in the assay method, ABTS + The free radical scavenging rate was calculated as follows: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%.

[0067] Example 1

[0068] The present invention provides a 6-O-Caffeoylarbutin compound, the structural formula of the 6-O-Caffeoylarbutin compound is shown in formula (I):

[0069]

[0070] Example 2

[0071] A method for preparing a 6-O-Caffeoylarbutin compound of the present invention comprises the following steps:

[0072] a. Take the dried Yunnan Golden Flower tea leaves and crush them into 40 mesh;

[0073] b. Using 95% industrial methanol at 60°C for condensation reflux extraction 3 times, each time for 1 hour;

[0074] c. Combine the extracts, use a rotary evaporator at 40°C and low pressure to recover methanol to obtain a methanol extract; the methanol used is industrial grade methanol;

[0075] d. Mix the methanol extract with distilled water, and extract with petroleum ether and ethyl acetate in turn; the petroleum ether and ethyl acetate used are both industrial grade; the temperature of the petroleum ether is 60°C.

[0076] e. After the solvent is recovered, a petroleum ether extract and an ethyl acetate extract are obtained, and the remaining aqueous phase is concentrated at high temperature and low pressure to obtain an aqueous extract of Yunnan Camellia chrysantha;

[0077] f. Use macroporous resin D101 to mix the sample and load it onto the column, and elute it with a water / methanol gradient to obtain a 40% methanol water extract; the volume ratio of water to methanol is 100:0-0:100;

[0078] g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 components Fr. (AJ); in the gel column chromatography, the volume ratio of water to methanol was 80:20-0:100;

[0079] h. Purification by silica gel column chromatography and semi-preparative high performance liquid chromatography (PHPLC) to obtain a monomer compound 6-O-Caffeoylarbutin. The silica gel used was 200 mesh.

[0080] The Yunnan golden camellia water phase extract of the invention is obtained by a method.

[0081] Example 3

[0082] The difference between Example 3 and Example 2 is that: a method for preparing a 6-O-Caffeoylarbutin compound of the present invention comprises the following steps:

[0083] In step a, a dried sample of Yunnan golden flower tea is taken and crushed into 60 meshes;

[0084] In step b, 95% industrial methanol is used to perform condensation reflux extraction at 40° C. for 3 times, each time for 2 hours;

[0085] In step c, the extracts are combined, and methanol is recovered by a rotary evaporator at 60° C. under low pressure to obtain a methanol extract; the methanol used is industrial grade methanol;

[0086] In step d, the methanol extract is mixed with distilled water, and extracted with petroleum ether and ethyl acetate in sequence; the petroleum ether and ethyl acetate used are both industrial grade; and the temperature of the petroleum ether is 80°C.

[0087] In step f, a macroporous resin D101 is used to mix the sample and load it onto a column, and a water / methanol gradient elution is performed to obtain a 40% methanol water extract; the water:methanol gradient elution has a volume ratio of water to methanol of 100:0-0:100;

[0088] In step g, elution is performed using a Sephadex LH-20 gel column to obtain 10 components Fr. (AJ); in gel column chromatography, gradient elution is performed, and the volume ratio of water to methanol is 80:20-0:100;

[0089] In step h, the monomer compound 6-O-Caffeoylarbutin is obtained by purification by silica gel column chromatography and semi-preparative high performance liquid chromatography (PHPLC). The silica gel used is 300 mesh.

[0090] Example 4

[0091] The difference between Example 4 and Example 2 is that: a method for preparing a 6-O-Caffeoylarbutin compound of the present invention comprises the following steps: in step a, taking a dry sample of Yunnan golden flower tea leaves and crushing it into 80 meshes;

[0092] In step b, 95% industrial methanol is used to perform condensation reflux extraction at 40° C. for 3 times, each time for 3 hours;

[0093] In step c, the extracts are combined, and methanol is recovered by a rotary evaporator at 50° C. under low pressure to obtain a methanol extract; the methanol used is industrial grade methanol;

[0094] In step d, the methanol extract is mixed with distilled water, and extracted with petroleum ether and ethyl acetate in sequence; the petroleum ether and ethyl acetate used are both industrial grade; and the temperature of the petroleum ether is 90°C.

[0095] In step f, a macroporous resin D101 is used to mix the sample and load it onto a column, and a water / methanol gradient is used for elution to obtain a 40% methanol water extract; the volume ratio of water to methanol is 100:0-0:100;

[0096] In step g, a Sephadex LH-20 gel column is used for elution to obtain 10 components Fr. (AJ); in the gel column chromatography, the volume ratio of water to methanol is 80:20-0:100;

[0097] In step h, the monomer compound 6-O-Caffeoylarbutin is obtained by purification through silica gel column chromatography and semi-preparative high performance liquid chromatography (PHPLC). The silica gel used is 200 mesh.

[0098] Example 5

[0099] The invention discloses an application of a high-activity 6-O-Caffeoylarbutin phenolic compound in the preparation of an antioxidant preparation.

[0100] The present invention discloses a composition containing the 6-O-Caffeoylarbutin according to claim 1, wherein the composition is used for anti-oxidation.

[0101] The method of the present invention for determining the antioxidant activity of 6-O-Caffeoylarbutin according to claim 1, using ABTS + The free radical scavenging rate is used as the test index. In the determination method, ABTS + The free radical scavenging rate was calculated as follows: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%.

[0102] Test Example 1

[0103] 1. Instruments and Materials

[0104] BrukerAV 500MHz nuclear magnetic resonance instrument (Bruker, Germany), XEVO G2-XS Q-TOF high-resolution mass spectrometer (Waters, USA), NP7000 semi-preparative liquid phase (Jiangsu Hanbang Technology Co., Ltd., China), AX224ZH\E electronic balance (Ohaus Instrument (Changzhou) Co., Ltd., China), 101-2ES electric heating blast drying oven (Beijing Yongguangming Medical Instrument Co., Ltd., China), N-1300 rotary evaporator, CA-111 cold trap (Shanghai Ailang Instrument Co., Ltd., China), SHZ-DⅢ circulating water vacuum pump (Gongyi Yuhua Instrument Co., Ltd., China), ZF-7 three-purpose UV analyzer (Shanghai Jiapeng Technology Co., Ltd., China), column chromatography process reagents are all industrial grade.

[0105] The voucher specimen of Yunnan Camellia fascicularis (52860) was identified by taxonomist Min Tianlu and preserved in the herbarium of Kunming Institute of Botany, Chinese Academy of Sciences. The Yunnan Camellia fascicularis tea leaves used in this experiment were obtained from Daweishan Nature Reserve, Hekou County, Yunnan Province, China in December 2019 and identified as Yunnan Camellia fascicularis by Professor Xiang Jianying, a taxonomist at Southwest Forestry University.

[0106] 2 Extraction and separation

[0107] Take 10.7kg of dry Yunnan Golden Flower tea sample, crush it into 40-80 mesh, and then use 95% industrial methanol at 40-60℃ to condense and reflux for 3 times, each time for 1-3h. Combine the extracts, use a rotary evaporator at 40-60℃ to recover the industrial methanol, and get 868.3g of Yunnan Golden Flower tea methanol extract. Add 5L of distilled water to mix it thoroughly, and extract it with petroleum ether (60-90℃) and ethyl acetate in turn. After recovering the solvent, 347.2g of petroleum ether extract and 177.8g of ethyl acetate extract were obtained. After the remaining aqueous phase was concentrated at high temperature and low pressure, 115.6g of Yunnan Golden Flower tea aqueous extract was obtained. 110.0g of extract was mixed with 170.0g of macroporous resin D101 and loaded onto the column with V 水 / 甲醇 =1:0-0:1 gradient elution, 40% methanol water to obtain 30.0g of extract. Sephadex LH-20 gel column (V 水 / 甲醇 =80:20-0:100) was eluted to obtain 10 components Fr. (AJ).

[0108] Fr.C (8.0 g) 12 g silica gel (200-300 mesh) was used for silica gel column chromatography. 氯仿：甲醇 =20:1-1:1 gradient elution, TLC detection, combine the same parts to obtain 4 components Fr. (CA-CD), Fr. CA (3.9g) 6.0g silica gel (200-300 mesh) and the sample were subjected to silica gel column chromatography, V 氯仿：甲醇：水 =8:2:0.2-6:4:1 gradient elution, TLC detection, combine the same parts to obtain 4 components Fr. (CAA-CAD), Fr. CAA (409 mg) 1.0 g silica gel (200-300 mesh) and the sample were subjected to silica gel column chromatography, V 氯仿：甲醇 =20:1-1:1 gradient elution, TLC detection, and merging of the same parts to obtain 7 components Fr. (CAA1-CAA7), Fr.CAA2 was finally purified by semi-preparative high performance liquid chromatography (PHPLC) to obtain monomer compound 1 (separation and purification process see Figure 1 ).

[0109] Figure 1 This is a separation flow chart of compound 1 of Test Example 1 of the present invention;

[0110] 3 Structural analysis

[0111] 6-O-Caffeoylarbutin(1):Amorphous powder, HR-ESI-MS m / z 457.1180[M+Na] + , molecular formula is C 21 H 22 O 10 .

[0112] 1H NMR (500MHz, Methanol-d 4 )δ H 7.54(1H,d,J=15.8Hz,Hb),7.02(1H,d,J=2.1Hz,H-2),6.91(3H,d,J=8.9Hz,H-6,2 ”,6”),6.76(1H,d,J=8.1Hz,H-5),6.62(2H,d,J=8.9Hz,H-3”,5”),6.25(1H,d,J=1 5.9Hz,Ha),4.69(1H,d,J=7.1Hz,H-1'),4.49(1H,d,J=11.9Hz,H-6'b),4.31(1H,d d,J=11.9,6.6Hz,H-6'a),3.65-3.58(1H,m,H-5'),3.44-3.36(3H,m,H-2',3',4'). 13 C NMR (126MHz, 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 in Figure 3 shown.

[0113] 4 Antioxidant Activity

[0114] The experiment used a 96-well plate with a total volume of 210 μL per well. Equal volumes of ABTS solution (7 mM) and potassium persulfate solution (5 mM) were mixed evenly 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 an absorbance of 0.7 ± 0.02 at 734 nm. Then, 180 μL of ABTS working solution was added to each well, followed by 30 μL of samples of different concentrations (0.5, 0.1, 0.05, 0.01 mg / mL), dissolved and diluted with DMSO. After mixing evenly, the samples were incubated at room temperature in the dark for 6 min. Then, the absorbance value of each well was 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 were used as positive controls.

[0115] The ABTS radical cation scavenging rate (%) of each test sample was calculated as follows (1):

[0116] ABTS clearance rate (%) = [blank - (sample - control)] / blank × 100% (1)

[0117] The ABTS test results are shown in Table 1:

[0118] Table 1

[0119]

[0120] "-" means the experiment was not performed.

[0121] Compound 1 at a concentration of 10-500 μg / mL, ABTS + In the free radical scavenging experiment, it showed significant activity that was superior to the positive control (ascorbic acid and β-arbutin). This result shows that compound 1 may have a more excellent effect in scavenging free radicals and resisting oxidative stress. This discovery has brought new candidate substances to the field of antioxidants, which will help to further explore its mechanism of action and potential applications. Figure 2 It is the preparation liquid phase separation diagram of the present invention; Figure 3 For the present invention 1 HNMR and 13 C NMR spectrum.

[0122] The above shows and describes 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 by the above test examples, and the above test examples and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and the scope of protection of the present invention is defined by the attached claims, description and their equivalents.

Claims

1. An arbutin derivative 6-O-Caffeoylarbutin, characterized in that: The structural formula of the arbutin derivative 6-O-Caffeoylarbutin is shown in formula (I):

2. The method for preparing the arbutin derivative 6-O-Caffeoylarbutin according to claim 1, characterized in that The steps include: a. Take the dried Yunnan Golden Flower tea leaves and crush them into 40-80 mesh; b. Use 95% industrial methanol to perform condensation reflux extraction at 40-60°C for 3 times, each time for 1-3 hours; c. Extraction: Combine the extracts and use a rotary evaporator to recover methanol at 40-60°C under low pressure to obtain a methanol extract; d. Extraction: Mix the methanol extract with distilled water and extract with petroleum ether and ethyl acetate in sequence; e. After the solvent is recovered, a petroleum ether extract and an ethyl acetate extract are obtained, and the remaining aqueous phase is concentrated at high temperature and low pressure to obtain an aqueous extract of Yunnan Camellia chrysantha; f. Use macroporous resin D101 to mix the sample and load it onto the column, and elute it with a water / methanol gradient to obtain a 40% methanol water extract; g. Elution was performed using a Sephadex LH-20 gel column to obtain 10 components Fr., components A to J; h. The compound 6-O-Caffeoylarbutin was obtained by purification by silica gel column chromatography and preparative high performance liquid chromatography (PHPLC).

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

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

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

6. Use of the arbutin derivative 6-O-Caffeoylarbutin according to claim 1 in the preparation of antioxidant preparations.

7. A composition containing the 6-O-Caffeoylarbutin according to claim 1, characterized in that: The composition is used for anti-oxidation.

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

9. The method according to claim 8, characterized in that: In the assay method described, ABTS + The free radical scavenging rate was calculated as follows: ABTS scavenging rate (%) = [blank - (sample - control)] / blank × 100%.

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