Emodin succinyl ester compound, preparation method therefor and application thereof

Abstract

Disclosed in the present invention are an emodin succinyl ester compound, a preparation method therefor and a use thereof, the emodin succinyl ester compound having the structure as represented by formula I (R being a C.sub.1-5 alkyl group). The method provided in the present invention has a simple method course, and may effectively save time in synthesis and reduce costs, being simple to operate, being easy to implement, and being suitable for industrial production. Experiments show that the emodin succinyl ester compound of the present invention may better promote the healing of diabetic wounds than emodin, and may be used for preparing a drug for promoting the healing of diabetic wounds. Moreover, it has been confirmed by means of performing pharmacological experiments on rats suffering from experimentally mixed hyperlipidemia that the emodin succinyl ester compound of the present invention is superior to emodin, and has the advantages of having a remarkable blood fat lowering effect, being safe, being simple and convenient to administer, the raw materials being low cost and readily available, and being easy to transport and store.

Claims

1. An emodin succinyl ester compound, having a structure represented by Formula I: ##STR00003## where R represents C.sub.1-5 alkyl.

2. The emodin succinyl ester compound according to claim 1, wherein in Formula I, R represents ethyl.

3. A method for preparing the emodin succinyl ester compound according to claim 1, comprising reacting succinic anhydride and a C.sub.1-5 alkanol; reacting the monoalkanol succinate with thionyl chloride to obtain succinate monoalkanol ester acyl chloride; and reacting the succinate monoalkanol ester acyl chloride with emodin to obtain the emodin succinyl ester compound.

4. The method according to claim 3, comprising the following steps: (1) refluxing succinic anhydride in the presence of C.sub.1-5 alkanol as solvent, followed by reduced-pressure distillation to remove excess alkanol, thus obtaining a monoalkanol succinate, wherein the monoalkanol succinate is subjected to the next reaction without separation; (2) refluxing the monoalkanol succinate in the presence of thionyl chloride as solvent, followed by reduced-pressure distillation to remove excess thionyl chloride, thus obtaining succinate monoalkanol ester acyl chloride compound, wherein the compound is subjected to the next reaction without separation; (3) placing the emodin and an alkali in a round-bottomed flask, adding the succinate monoalkanol ester acyl chloride dropwise in the presence of dichloromethane as solvent, and reacting at room temperature; (4) extracting with a sodium hydrogen carbonate solution, combining organic phases, extracting the organic phases with saturated brine, combining organic phases, drying with anhydrous sodium sulfate, filtering, and concentrating under reduced pressure to obtain a crude product; and (5) chromatographing the crude product on a silica gel column and eluting with a dichloromethane-methanol mixed solution to obtain the emodin succinyl ester.

5. The method according to claim 4, comprising the following steps when R represents ethyl: (1) refluxing succinic anhydride in the presence of ethyl alcohol as solvent, followed by reduced-pressure distillation to remove excess ethyl alcohol, thus obtaining monoethyl succinate, wherein the monoethyl succinate is subjected to the next reaction without separation; (2) refluxing the monoethyl succinate in the presence of thionyl chloride as solvent, followed by reduced-pressure distillation to remove excess thionyl chloride, thus obtaining succinate monoethyl ester acyl chloride, wherein the succinate monoethyl ester acyl chloride is subjected to the next reaction without separation; (3) placing the emodin and an alkali in a round-bottomed flask, adding the succinate monoethyl ester acyl chloride dropwise in the presence of a solvent, dichloromethane, and reacting at room temperature; (4) extracting with a sodium hydrogen carbonate solution, combining organic phases, extracting the organic phases with saturated brine, combining organic phases, drying with anhydrous sodium sulfate, filtering, and concentrating under reduced pressure to obtain a crude product; and (5) chromatographing the crude product on a silica gel column and eluting with a dichloromethane-methanol mixed solution to obtain the emodin succinyl ethyl ester.

6. The method according to claim 4, wherein the alkali in step (3) is selected from weak alkalis.

7. The method according to claim 5, wherein, in step (1), the time of heating reflux is 3-10 hours, and the ratio (g:ml) of the mass of succinic anhydride to the volume of ethanol is 1:10; in step (2), the time of heating reflux is 1-10 hours, and the mass ratio of monoethyl succinate to thionyl chloride is 1:1-1:10, in step (3), the alkali is pyridine, triethylamine, or ammonia, and the mass ratio of emodin to succinate monoethyl ester acyl chloride is 1:0.5-1; in step (5), in the dichloromethane-methanol mixed solution, the volume ratio of dichloromethane to methanol is 100:1-100:4.

8. A composition comprising the emodin succinyl ester compound according to claim 1 for use in a pharmaceutical composition for diabetic wound healing.

9. A pharmaceutical composition, comprising the emodin succinyl ester compound according to claim 1, and optionally one or more excipients, wherein the pharmaceutical composition is selected from cream, oil, patch, powder, spray, sustained release agent preparation, capsule, tablet, granule, or injection.

10. An oily preparation, comprising the emodin succinyl ester compound according to claim 1 and a vegetable oil.

11. A method for preparing the oily preparation according to claim 10, comprising the following steps: (1) heating vegetable oil to a browned state for sterilization, resting at room temperature, and cooling for later use; (2) weighing the emodin succinyl ester compound according to claim 1 under an aseptic condition and dissolving the compound in the vegetable oil after sterilization in step (1); wherein, the ratio (mg:ml) of the mass of the succinyl ester compound to the volume of the vegetable oil is 1-5:1; (3) carrying out ultrasonic vibration on the vegetable oil which contains the emodin succinyl ethyl ester, so that the emodin succinyl ethyl ester is fully dissolved to form a uniform oily preparation; and (4) diluting the oily preparation obtained in step (3) with sterile water, sub-packaging under an aseptic condition, sealing, and storing at room temperature for later use; wherein, in the oily preparation diluted with sterile water, the concentration of the emodin succinyl ester compound is 50-150 μg/mL.

12. The emodin succinyl ester compound according to claim 1 for use in a pharmaceutical composition for lowering blood lipids and/or for treating fatty liver.

13. The emodin succinyl ester compound according to claim 12 for use in the lipid-lowering pharmaceutical composition, wherein the lipid-lowering pharmaceutical composition reduces total cholesterol (TC), low-density lipoprotein (LDL-C) in a serum, and a TC and triglycerides (TG) in a liver.

14. The method according to claim 7, wherein, in step (1), the time of heating reflux is 4 hours, and the ratio (g:ml) of the mass of succinic anhydride to the volume of ethanol is 1:4; in step (2), the time of heating reflux is 2 hours, and the mass ratio of monoethyl succinate to thionyl chloride is 1:4; in step (3), the alkali is pyridine, and the mass ratio of emodin to succinate monoethyl ester acyl chloride is 1:0.7; in step (5), in the dichloromethane-methanol mixed solution, the volume ratio of dichloromethane to methanol is 100:1.

15. A method for preparing the oily preparation according to claim 11, comprising the following steps: (1) heating vegetable oil to a browned state for sterilization, resting at room temperature, and cooling for later use; (2) weighing the emodin succinyl ester compound according to claim 1 under an aseptic condition and dissolving in the vegetable oil after sterilization in step (1); wherein, the ratio (mg:ml) of the mass of the succinyl ester compound to the volume of the vegetable oil is 4:1; (3) carrying out ultrasonic vibration so that the emodin succinyl ethyl ester is fully dissolved to form a uniform oily preparation; and (4) diluting the oily preparation obtained in step (3) with sterile water, sub-packaging under an aseptic condition, sealing, and storing at room temperature for later use; wherein, in the oily preparation diluted with sterile water, the concentration of the emodin succinyl ester compound is 100 μg/mL.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a synthetic route map of an emodin succinyl ester compound.

(2) FIG. 2 is a schematic diagram of two-dimensional nuclear magnetic resonance related signals of emodin succinyl ethyl ester.

(3) FIG. 3 shows the blood glucose values of mice in each group,

(4) where, A: blood glucose value of mice in each group after the establishment of a diabetes model; B: blood glucose value of mice in each group before the end of administration,

(5) the values are expressed as mean±standard error; after STZ administration, the successfully modeled animals were randomly divided into model control group, solvent control group, positive drug (recombinant human epidermal growth factor) control group, emodin group, and emodin succinyl ethyl ester according to blood glucose levels, 6 mice per group (′: compared with the blank control group, P<0.001, n=6).

(6) FIG. 4 is an illustrative diagram of the effect of emodin succinyl ethyl ester on wound healing in mice.

(7) FIG. 5 is a fitting curve plot of the effect of emodin succinyl ethyl ester on the wound healing rate of mice,

(8) where, values are expressed as mean±standard error; *: compared with the model group, P<0.05; .sup.###: compared with the emodin succinyl ethyl group, P<0.001, n=4-6).

(9) FIG. 6 shows the levels of TC, TG and LDL-c in the serum of animals after the establishment of a hyperlipidemia model,

(10) where, data are expressed as mean±standard error, *P<0.05 vs. blank control group, **P<0.01 vs. blank control group, blank control group, n=10; hyperlipidemia model group, n=10; low-dose test object group, n=10; medium-dose test object group, n=10; high-dose test object group, n=10; atorvastatin calcium group: positive control drug group, n=11.

(11) FIG. 7 shows the effect of emodin succinyl ethyl ester on the blood lipid levels in rats with mixed hyperlipidemia,

(12) where, data are expressed as mean±standard error, *P<0.05 vs. blank control group, **P<0.01 vs. blank control group, ***P<0.001 vs. blank control group, .sup.#P<0.05 vs. hyperlipidemia model group, .sup.##P<0.01 vs. hyperlipidemia model group, .sup.###P<0.001 vs. hyperlipidemia model group; blank control group, n=10; hyperlipidemia model group, n=10; low-dose test object group, n=10; medium-dose test object group, n=10; high-dose test object group, n=10; atorvastatin calcium group: positive control drug group, n=11.

(13) FIG. 8 shows the effect of emodin succinyl ethyl ester on the levels of TC and TG in the liver of rats with mixed hyperlipidemia,

(14) where data are expressed as mean±standard error, *P<0.05 vs. blank control group, **P<0.01 vs. blank control group, ***P<0.001 vs. blank control group, .sup.#P<0.05 vs. hyperlipidemia model group, .sup.##P<0.01 vs. hyperlipidemia model group, .sup.###P<0.001 vs. hyperlipidemia model group; blank control group, hyperlipidemia model group, and low-dose test object group, medium-dose test object group, high-dose test object group and atorvastatin calcium group: positive control drug group, n=5 for each group.

(15) FIG. 9 shows the levels of TC and LDL-c in animal serum after the establishment of a hyperlipidemia model,

(16) where, data are expressed as mean±standard error, *P<0.05 vs. blank control group, **P<0.01 vs. blank control group, ***P<0.01 vs. blank control group, blank control group, n=10; hyperlipidemia model group, n=10; test object (emodin succinyl ethyl ester) group, n=10; emodin group, n=10; atorvastatin calcium group: positive control group, n=11.

(17) FIG. 10 shows comparison of the effects of emodin succinyl ethyl ester and emodin in lowering blood lipid levels in rats with mixed hyperlipidemia,

(18) where, data are expressed as mean±standard error, *P<0.05 vs. blank control group, **P<0.01 vs. blank control group, ***P<0.001 vs. blank control group, .sup.#P<0.05 vs. hyperlipidemia model group, .sup.##P<0.01 vs. hyperlipidemia model group, .sup.###P<0.001 vs. hyperlipidemia model group, &P<0.05 vs. emodin group; blank control group, n=10; hyperlipidemia model group, n=10; test object (emodin succinyl ethyl ester) group, n=10; emodin group, n=10; atorvastatin calcium group: positive control drug group, n=11.

(19) FIG. 11 shows the effect of emodin succinyl ethyl ester on the levels of TC and TG in oleic acid-induced hyperlipemia cells.

(20) where, data are expressed as mean±standard error, ***P<0.001 vs. blank control group, .sup.#P<0.05 vs. oleic acid group, .sup.##P<0.01 vs. oleic acid group, .sup.###P<0.001 vs. oleic acid group, blank control group, n=6; oleic acid group, n=6; low-dose test object (emodin succinyl ethyl ester in a dose of 5 μmol/L) group, n=6; medium-dose test object (emodin succinyl ethyl ester in a dose of 10 μmol/L) group, n=6; high-dose test object (emodin succinyl ethyl ester in a dose of 20 μmol/L) group, n=6.

DETAILED DESCRIPTION OF EMBODIMENTS

(21) The present invention is further described below with reference to specific embodiments. The advantages and features of the present invention will become more clear with the description. However, these embodiments are only exemplary and do not limit the scope of the present invention in any way. Those skilled in the art should understand that the details and forms of the technical solutions of the present invention can be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements fall within the scope of the present invention.

Example 1 Preparation of Emodin Succinyl Ethyl Ester

(22) Succinic anhydride (1.0 g, 10 mmol) is placed in a 10 ml round-bottomed flask and is subjected to heating reflux for 4 hours in the presence of ethyl alcohol (3.5 mL, 60 mmol) as solvent, and excess ethyl alcohol is removed by reduced-pressure distillation, and then a pale yellow oily substance, i.e., monoethyl succinate (1.4 g, 96%), is obtained. The product is directly subjected to the next reaction without separation.

(23) The monoethyl succinate (1.0 g, 6.8 mmol) is placed in a 10 ml round-bottomed flask and is subjected to heating reflux for 2 hours in the presence of a solvent, sulfoxide chloride (4.0 g, 34.0 mmol), and excess sulfoxide chloride is removed by reduced-pressure distillation, and then a pale yellow oily substance, i.e., succinate monoethyl ester acyl chloride (1.1 g, 98%), is obtained. The product is directly subjected to the next reaction without separation.

(24) Emodin (1.0 g, 3.7 mmol) and pyridine (0.45 g, 5.6 mmol) are placed in a 10 mL round-bottomed flask, and succinate monoethyl ester acyl chloride (0.7 g, 4.0 mmol) is added dropwise in a slow manner in the presence of a solvent dichloromethane (3 mL) at 0° C. and reacted at room temperature for 3 hours.

(25) The reaction product is extracted with a sodium hydrogen carbonate solution (2 mL×3); organic phases are combined and extracted with saturated brine (3 mL×3); organic phases are combined, dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product which is a purple-yellow solid.

(26) The crude product is chromatographed on a silica gel column and eluted with a dichloromethane-methanol mixed solution (v/v 100:1) to obtain 1.4 g of a pale yellow pure product. The yield of the pure product is 94.7% and the purity of the pure product is 97%.

(27) The synthetic route map of the emodin succinyl ester compound is shown in FIG. 1, where R represents ethyl.

Example 2 Preparation of Emodin Succinyl Ethyl Ester

(28) Succinic anhydride (10 g, 100 mmol) is placed in a 150 ml round-bottomed flask and is subjected to heating reflux for 6 hours in the presence of ethyl alcohol (40 mL, 600 mmol) as solvent, and excess ethyl alcohol is removed by reduced-pressure distillation, and then a pale yellow oily substance, i.e., monoethyl succinate (14 g, 96%), is obtained. The product is directly subjected to the next reaction without separation.

(29) The monoethyl succinate (10 g, 68 mmol) is placed in a 150 ml round-bottomed flask and is subjected to heating reflux for 2 hours in the presence of sulfoxide chloride (40 g, 340 mmol) as solvent, and excess sulfoxide chloride is removed by reduced-pressure distillation, and then a pale yellow oily substance, i.e., succinate monoethyl ester acyl chloride (11 g, 98%), is obtained. The product is directly subjected to the next reaction without separation.

(30) Emodin (10 g, 37 mmol) and pyridine (2.3 g, 22 mmol) are placed in a 250 mL round-bottomed flask, and succinate monoethyl ester acyl chloride (7 g, 40 mmol) is added dropwise in a slow manner in the presence of dichloromethane (3 mL) as solvent at 0° C. and reacted at room temperature for 3 hours. The reaction product is extracted with a sodium hydrogen carbonate solution (20 mL×3); organic phases are combined and extracted with saturated brine (30 mL×3); organic phases are combined, dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product which is a purple-yellow solid.

(31) The crude product is chromatographed on a silica gel column and eluted with a dichloromethane-methanol mixed solution (v/v 100:1) to obtain 12.7 g of a pale yellow pure product. The yield of the pure product is 92.3% and the purity of the pure product is 98% or above.

(32) The synthetic route map of the emodin succinyl ester compound is shown in FIG. 1, where R represents ethyl.

Example 3 Preparation of Emodin Succinyl Ethyl Ester

(33) Succinic anhydride (10 g, 100 mmol) is placed in a 150 ml round-bottomed flask and is subjected to heating reflux for 2 hours in the presence of ethyl alcohol (20 mL, 434 mmol) as solvent, and excess ethyl alcohol is removed by reduced-pressure distillation, and then a pale yellow oily substance, i.e., monoethyl succinate (14 g, 96%), is obtained. The product is directly subjected to the next reaction without separation.

(34) The monoethyl succinate (10 g, 68 mmol) is placed in a 150 ml round-bottomed flask and is subjected to heating reflux for 1 hours in the presence of sulfoxide chloride (20 g, 170 mmol) as solvent, and excess sulfoxide chloride is removed by reduced-pressure distillation, and then a pale yellow oily substance, i.e., succinate monoethyl ester acyl chloride (8 g, 98%), is obtained. The product is directly subjected to the next reaction without separation.

(35) Emodin (10 g, 37 mmol) and pyridine (1.5 g, 44 mmol) are placed in a 250 mL round-bottomed flask, and succinate monoethyl ester acyl chloride (8 g, 45 mmol) is added dropwise in a slow manner in the presence of dichloromethane (3 mL) as solvent at room temperature and reacted at room temperature for 1 hour. The reaction product is extracted with a sodium hydrogen carbonate solution (20 mL×3); organic phases are combined and extracted with saturated brine (30 mL×3); organic phases are combined, dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product which is a purple-yellow solid.

(36) The crude product is chromatographed on a silica gel column and eluted with a dichloromethane-methanol mixed solution (v/v 100:1) to obtain 8 g of a pale yellow pure product. The yield of the pure product is 54.1% and the purity of the pure product is 98% or above.

(37) The synthetic route map of the emodin succinyl ester compound is shown in FIG. 1, where R represents ethyl.

Example 4 Structure Identification of the Target Compound

(38) The structure of the compounds prepared in Examples 1-3 was identified. The identification results showed that the compound was emodin succinyl ethyl ester, a yellow powder, dissolved in methanol, [α].sub.D.sup.260.0° (c0.5, CHCl.sub.3). IR (KBr, cm.sub.−1) 3500 (—OH), 3088 (Ar—H), 2981 (RH), 1763 (C=0), 1730 (C=0), 1624 (benzene ring), 1481 (benzene ring). UV [nm (loge), MeOH]: 278 (3.37), 268 (3.40). CD (nm, Δε, MeOH): 212 (−0.56). In .sub.1H-NMR, δ7.08 (1H, d, J=2.2 Hz) and 7.33 (1H, d, J=2.2 Hz) are proton signals coupled in meta position on the benzene ring. 67.39 (1H, brs) and 7.07 (1H, brs) are aromatic proton signals, δ2.91 (2H, d, J=6.2), 2.71 (2H, d, J=6.2 Hz), and 4.13 (2H, q, J=7.1 Hz) are three methylene proton signals, and δ 2.36 (3H, s) and 1.22 (3H, t, J=7.1 Hz) are methyl proton signals. The carbon spectrum gives 21 carbon signals, of which 6190.8 and 181.0 are ketocarbonyl carbon signals, δ172.0 and 170.6 are ester carbonyl carbon signals, and 163.2, 162.0 and 157.0 are oxygenated carbon signals on the benzene ring. In the .sub.1H-.sub.1HCOSY spectrum, δ2.91 and 2.71 have correlated signals, and 64.13 and 1.22 have correlated signals. According to the DEPT spectrum of the compound, the structure of the compound contains 4 sp2 hybridized methine carbon signals, 12 sp.sub.2 hybridized quaternary carbon signals, 3 sp.sub.3 hybridized methylene carbon signals, and 2 methyl carbon signals. Its hydrocarbon signals were assigned by HMQC spectrum. In the HMBC spectrum, the proton of δ7.08 is remotely correlated to chemical shifts of 163.2 and 114.3, the proton of δ7.33 is remotely correlated to carbon signals of 157.0, 181.0, and 114.3, the proton of δ7.39 is remotely correlated to carbon signals of δ149.5, 181.0, and 113.8, and the proton of δ7.07 is remotely correlated to the carbon signals of δ162.2 and 113.8. The proton at δ2.91 is remotely correlated with the carbon signal of δ170.6, the proton of δ2.71 is remotely correlated with the carbon signal of δ172.2, the proton of δ4.13 is remotely correlated with the carbon signal of δ172.2, the proton of δ1.22 is remotely correlated to the carbon signal of δ60.7, and the methyl proton of 2.36 is remotely correlated to the carbons of 121.1, 149.5, and 116.7. Based on the above information, the structure of the compound is determined as shown in Formula I below, and the signal assignment is shown in Table 1. Two-dimensional nuclear magnetic resonance (NMR) related signals of emodin succinyl ethyl ester are shown in Table 2.

(39) ##STR00002##

(40) TABLE-US-00001 TABLE 1 NMR data (600 MHz, DMSO-d6) of emodin succinyl ethyl ester 1H-1H Position .sup.1H-NMR .sup.13C-NMR DEPT COSY HMBC 1 — 163.2 C — — 2 7.08 124.6 —CH— H-4 C-1,9a (1H, d, J = 2.2 Hz) 3 — 157.0 C — — 4 7.33 113.4 —CH— H-2 C-3,10,9a (1H, d, J = 2.2 Hz) 5 7.39(1H, brs) 121.1 —CH— H-7 C-6,10,8a 6 — 149.5 C — — 7 7.07(1H, brs) 116.7 —CH— H-5 C-8,8a 8 — 162.0 C — — 9 — 190.8 C — — 10 — 181.0 C — — 4a — 135.0 C — — 8a — 113.8 C — — 9a — 114.3 C — — 10a — 135.0 C — — 1′ — 170.6 C — — 2′ 2.91(2H, d, J = 6.2) 29.5 —CH.sub.2— H-2′ C-1′ 3′ 2.71 29.0 —CH.sub.2— H-3′ C-4′ (2H, d, J = 6.2 Hz) 4′ — 172.2 C — — 1″ 4.13 60.7 —CH.sub.2— H-1″ C-4′ (2H, q, J = 7.1 Hz) 2″ 1.22 14.5 —CH.sub.3 H-2″ C-1″ (3H, t, J = 7.1 Hz) 6—CH.sub.3 2.36(3H, s) 22.0 —CH.sub.3 — C-5,6,7

Example 5 Efficacy Test 1 of the Product of the Present Invention

(41) 1. Preparation of Drug

(42) (1) Preparation of Emodin Succinyl Ethyl Ester Oil

(43) {circle around (1)} weighing 10 mg of emodin succinyl ethyl ester (prepared in Examples 1-3) in 2.5 mL of vegetable oil cooled after boiling;

(44) {circle around (2)} carrying out ultrasonic vibration for 10 minutes so that the emodin succinyl ethyl ester is fully dissolved; and

(45) {circle around (3)} diluting the emodin succinyl ethyl ester to 100 μg/mL with the aseptically cooled vegetable oil, aseptically sub-packaging, sealing and storing at room temperature for later use.

(46) (2) Preparation of Emodin Oil

(47) {circle around (1)} weighing 10 mg of emodin in 2.5 mL of vegetable oil cooled after boiling;

(48) {circle around (2)} carrying out ultrasonic vibration for 10 minutes so that the emodin is fully dissolved; and

(49) {circle around (3)} diluting the emodin to 200 μg/mL with the aseptically cooled vegetable oil, aseptically sub-packaging, sealing, and storing at room temperature for later use.

(50) 2. Experimental Methods

(51) 2.1 Establishment of a Mouse Diabetes Model

(52) SPF-grade male Kunming mice (18-20 g) were adaptively fed with ordinary maintenance feed for 3-5 days, weighed and randomly divided into a blank control group (Control) and a diabetes model group. Mice in the diabetes model group were administrated with high-dose STZ (streptozotocin, 180 mg/kg) through intraperitoneal injection and fasting blood glucose was measured after one week. The mice successfully modeled were randomly divided into 5 groups, namely, the diabetes model group (Model), the solvent control group (Solvent), the positive drug (recombinant human epidermal growth factor) control group (EGF), the emodin group (DHS), and the emodin succinyl ethyl ester group (DHS-YSW).

(53) 2.2 Establishment of Mouse Wound Model

(54) Animals in each group were anesthetized with sodium pentobarbital (1%) and shaved on the back. A 5 mm skin punch was used to establish a 5 mm wound model at the highest part of the back. The Control group and the Model group were not treated with any drugs. The solvent control group was dripped with 10 μL of sterile vegetable oil. The positive drug group was dripped with 10 μL of recombinant human epidermal factor solution (2000 IU/mL) each day. The other groups were dripped on the wound with 10 μL of a corresponding drug, once a day for 14 consecutive days.

(55) 2.3 Detection of Mouse Wound Area

(56) During the experiment, fixed-height fixed-focus photographs were taken daily to record the wound healing status of each group of mice. Image-Pro-Plus software was used to determine the wound area, and statistical analysis was performed on the wound healing status of each group of mice to estimate the effect of emodin succinyl ethyl ester oil on the wound healing process of mice with diabetes.
Wound healing rate=(wound area on day 0−wound area on day N)/wound area on day 0*100%

(57) 2.4 Statistical Methods

(58) The experimental data were expressed as mean±standard error. One-way ANOVA and T-test were used to statistically analyze the blood glucose values of the mice in each group. One-way ANOVA and paired T-test were used to statistically analyze the differences in wound healing rates of the mice. P<0.05 indicates significant differences. The experimental results were all analyzed and graphed using GraphpadPrism6.0.

(59) 3. Experimental Results

(60) 3.1 Blood Glucose of Each Group of Animals

(61) The results are shown in FIG. 3. It can be seen from FIG. 3 that after the high-dose STZ administration, the blood glucose levels of mice in the diabetes model group, the solvent control group, the positive drug control group (recombinant human epidermal growth factor, EGF), the emodin group, and the emodin succinyl ethyl ester group were significantly increased as compared with the blood glucose level of the blank control group (***P<0.001 vs. the blank control group). From the results, it can be seen that during the mouse wound healing experiment, except for the blank control group, the mice in each group were in a hyperglycemic state.

(62) 3.2 Effects of Emodin Succinyl Ethyl Ester on Wound Healing of Mice with Diabetes

(63) Results were shown in FIGS. 4 and 5, the mice in the diabetes model group had slower wound healing speed than the mice in the blank control group, while the mice in the emodin succinyl ethyl ester group had significantly faster wound healing speed than the mice in the diabetes model group, the solvent control group and the emodin group, and there were statistical differences (*P<0.05 vs. compared with the model group; .sup.###P<0.001 vs. emodin group; .sup.###P<0.001 vs. solvent control group). The results show that emodin succinyl ethyl ester can effectively speed up the wound healing of mice with diabetes, and has better curative effect than solvent and emodin, and its efficacy is stable and significant.

Example 6 Efficacy Test 1 of the Product of the Present Invention

(64) 1. Experimental Materials

(65) Experimental animals: 61 rats of uniform weight

(66) Test object: Emodin succinyl ethyl ester (prepared in Examples 1-3)

(67) High-fat feed: 20.0% of sucrose, 15.0% of lard, 1.2% of cholesterol, 0.2% of sodium cholate, an appropriate amount of casein, calcium hydrogen phosphate, stone powder, etc. were added to the maintenance feed. In addition to crude fat, the moisture, crude protein, crude fat, crude fiber, crude ash, calcium, and phosphorus of the model feed must meet the national standards for maintenance feed. The feed is clean grade, vacuum packed and stored at room temperature.

(68) 2. Experimental Principle

(69) Feeding rats with high-fat feed containing cholesterol, sucrose, lard, and sodium cholate can form a rat model of lipid metabolism disorders, and then the rats are administrated with drug, detect the effect of the test object on hyperlipidemia, and determine the effect of the test object on the lipid absorption, lipoprotein formation, lipid degradation or excretion in rats.

(70) Determination of mixed hyperlipidemia rat model: After the end of the modeling period, compared with the blank control group, rats in the hyperlipidemia model group have increased TG, TC or LDL-C in the serum, and the differences were significant, thus the establishment of the model is determined.

(71) 3. Experimental Methods

(72) 3.1 Animal Grouping

(73) First random grouping: After the animals are received, they are adaptively fed for 5 to 7 days. During the domestication period, the appearance and general state of the rats are observed. Only qualified rats can enter this experiment. After the end of the adaptation period, the rats were weighed and randomly divided into a blank control group (10 rats) and a hyperlipidemia model group (51 rats).

(74) Second random grouping: After the establishment of the rat hyperlipidemia model, the blood lipids of the rats were measured, and rats in the hyperlipidemia model group were randomly divided into five groups, 11 rats in the positive drug group, 10 rats in each of the other groups. The five groups were the hyperlipidemia model group, the low-dose test object group (emodin succinyl ethyl ester in a dose of 10 mg/kg.Math.d.sup.−1), the medium-dose test object group (emodin succinyl ethyl ester in a dose of 20 mg/kg.Math.d.sup.−1), the high-dose test object group (emodin succinyl ethyl ester in a dose of 40 mg/kg.Math.d.sup.−1), and the positive control drug group (Atorvastatin calcium group in a dose of 10 mg/kg.Math.d.sup.−1), respectively.

(75) 3.2 Establishment Period of Mixed Hyperlipidemia Model

(76) The administration and diet of the animals in each group are shown in Table 2. In the experimental groups, rats in the blank control group were fed with maintenance feed and the remaining 5 groups were fed with high-fat diet. After 2 weeks, the levels of TG, TC, LDL-C and HDL-C in the serum of the rats were measured. The rats were weighed once a week.

(77) Two weeks after the rats in the hyperlipidemia model group were given a high-fat diet, rats in the blank control group and the hyperlipidemia model group were not fasted to take blood from the tip of the tail. The serum was than separated and the levels of TC, TG, LDL-C and HDL-C in the serum were measured. According to the levels of TC, TG and LDL-C, the rats in the hyperlipidemia model group were randomly divided into 5 groups. After grouping, the hyperlipidemia model group, the low-dose test object group, the medium-dose test object group, the high-dose test object group, the positive control drug group (Atorvastatin calcium group) were compared with the blank control group in terms of TC, TG, LDL-C and HDL-C.

(78) The changes in blood lipids of rats in the hyperlipidemia model group and each administration group compared with the blank control group were observed. The results are shown in Table 3 and FIG. 6. After the establishment of the mixed hyperlipidemia model, compared with rats in each administration group and rats in the blank group, the rats in the hyperlipidemia model group had significant increase in TC (***P<0.001 vs. blank control group), TG (***P<0.001 vs. blank control group), **P<0.01 vs. blank control group, *P<0.05 vs. blank control group) and LDL-C (***P<0.001 vs. blank control group, **P<0.01 vs. blank control group) in the serum, all with statistical differences, and there was no significant difference in TC, TG and LDL-C among the administration groups. In this case, it could be determined that the mixed hyperlipidemia model was successfully established.

(79) TABLE-US-00002 TABLE 2 Drug administration and diet of animals in each group Admini- Num- Administration stration ber Group frequency cycle Dose Diet of rats Blank control Intragastrically Two 10 ml/kg Normal 10 group administered weeks (rat weight) once a day Hyperlipidemia Intragastrically Two 10 ml/kg High-fat 10 model group administered weeks (rat weight) once a day Low-dose test Intragastrically Two 10 mg/kg High-fat 10 object group administered weeks (rat weight) once a day Medium-dose Intragastrically Two 20 mg/kg High-fat 10 test object administered weeks (rat weight) group once a day High-dose test Intragastrically Two 40 mg/kg High-fat 10 object group administered weeks (rat weight) once a day Positive control Intragastrically Two 10 mg/kg High-fat 11 drug group administered weeks (rat weight) once a day

(80) Table Levels of TC, TG, LDL-C and HDL-C in animal serum after the establishment of a hyperlipidemia model

(81) TABLE-US-00003 Group TC (mmol/L) TG (mmol/L) LDL-C (mmol/L) Blank control 1.99 ± 0.35   3.02 ± 0.25  0.22 ± 0.41   group Hyperlipidemia 3.15 ± 0.61***  4.51 ± 0.86*** 0.41 ± 0.11*** mode group Low-dose test 3.00 ± 0.33*** 4.47 ± 1.33** 0.38 ± 0.09*** object group Medium-dose test  3.10 ± 0.3*7*** 4.49 ± 1.22** 0.37 ± 0.07*** object group High-dose test 3.00 ± 0.43*** 4.15 ± 0.97** 0.39 ± 0.10*** object group atorvastatin 3.00 ± 0.53*** 4.02 ± 1.16*  0.36 ± 0.10**  calcium group Note: Data are expressed as mean ± standard error, *P < 0.05 vs. blank control group, **P < 0.01 vs. blank control group, blank control group, n = 10; hyperlipidemia model group, n = 10; low-dose test object group, n = 10; medium-dose test object group, n = 10; high-dose test object group, n = 10; atorvastatin calcium group: positive control drug group, n = 11.

(82) 3.3 Administration Period

(83) The rats in the successfully grouped high-dose test object, medium-dose, and low-dose groups and positive control drug group (atorvastatin calcium group) were intragastrically administered daily. Rats in the blank control group and the hyperlipidemia model group were given corresponding doses of lysozyme. The doses of the groups are shown in Table 2.

(84) Feeding conditions remained unchanged. The rats were weighed once a week. Blood were collected at the tip of the tail two weeks after drug administration and livers were taken, to determine the levels of TC, TG, LDL-C, and HDL-C in serum of the rats and the levels of TC and TG in the liver, and then the effect of the test object on the TC, TG, LDL-C and HDL-C in serum of the rats and the TC and TG in liver were observed.

(85) 3.4 Observation Period

(86) General vital signs were observed during the experiment.

(87) 3.5 Main Detection Indicators

(88) (1) Weight, measured once a week.

(89) (2) TC, TG, LDL-C and HDL-C in serum, measured once after the establishment of the hyperlipidemia model and two weeks after administration.

(90) (3) TC and TG in liver, measured after sampling

(91) 4. Experimental Data and Results

(92) 4.1 Data Processing

(93) The analysis of variance is performed, but the homogeneity of variance test needs to be performed first according to the procedure of analysis of variance. If the variance is homogeneous, the F value is calculated, and 36F<0.05. Conclusion: There is no significant difference between the means of all the groups; F≥0.05, P≤0.05 and the statistics are made using a pairwise comparison of means between multiple experimental groups and one control group; appropriate variable conversion is performed on non-normal or heterogeneous-variance data, the data are used for statistics after the data after conversion become normal and homogeneous-variance data; if the data after conversion still are non-normal and heterogeneous-variance data, rank sum test could be performed for statistics.

(94) 4.2 Determination of Animal Experiment Results

(95) Determination of lipid-lowering effect: Compared with the blank control group, rats in the hyperlipidemia model control group had increased TG, TC or LDL-C in the serum, and the differences were significant, thus the establishment of the model is determined.

(96) (1) Compared with the model control group, rats in any dose group had reduced TC or LDL-C in serum and the rats in any dose group had reduced TG, with significant differences; moreover, the level of HDL-C in serum of rats in each dose group was not significantly lower than that in the model control group; thus, it could be determined that the test sample had a positive result in the animal experiment on blood lipid lowering function.

(97) (2) Compared with the model control group, rats in any dose group had reduced TC or LDL-C in serum, with significant differences; moreover, the TG in serum of rats in each dose group was not significantly higher than that in the model control group, and the level of HDL-C in serum of rats in each dose group was not significantly lower than that in the model control group; thus, it could be determined that the test sample had a positive result in the animal experiment on cholesterol lowering function.

(98) (3) Compared with the model control group, rats in any dose group had reduced TG in serum, with significant differences; moreover, the TC and LDL-C in serum of rats in each dose group were not significantly higher than those in the model control group, and the level of HDL-C in serum of rats in each dose group was not significantly lower than that in the model control group; thus, it could be determined that the test sample had a positive result in the animal experiment on TG lowering function.

(99) 4.3 Experimental Results

(100) The results are shown in Table 4 and FIG. 7. Two weeks after administration, compared with rats in the blank control group, rats in the mixed hyperlipidemia model group have significantly increased TC (*** P<0.001 vs. blank control group), TG (*** P<0.001 vs. blank control group) and LDL-C (*** P<0.001 vs. blank control group) in serum, thus determining the successful establishment of the model. Emodin succinyl ethyl ester in low, medium, high doses and atorvastatin calcium can significantly reduce TC (.sup.#P<0.05 vs. hyperlipidemia group) and LDL-C (.sup.#P<0.05 vs. hyperlipidemia group); emodin succinyl ethyl ester in a high dose and atorvastatin calcium can significantly reduce TG in serum of rats with hyperlipidemia (.sup.###P<0.001 vs. hyperlipidemia group).

(101) TABLE-US-00004 TABLE 4 Effect of emodin succinyl ethyl ester on the blood lipid levels in rats with mixed hyperlipidemia Group TC (mmol/L) TG (mmol/L) LDL-C (mmol/L) Blank control 2.38 ± 0.52.sup.  3.24 ± 0.11 0.09 ± 0.02 .sup.  group Hyperlipidemia  .sup. 3.53 ± 0.76***   4.37 ± 0.69***  0.24 ± 0.04*** mode group Low-dose test 2.60 ± 0.74.sup.# 3.98 ± 0.63 0.17 ± 0.08.sup.#  object group Medium-dose test .sup. 2.36 ± 0.78.sup.## 4.12 ± 0.37 0.15 ± 0.05.sup.### object group High-dose test 2.88 ± 0.34.sup.#  .sup. 3.23 ± 0.12.sup.### 0.18 ± 0.03.sup.##  object group Atorvastatin 2.82 ± 1.02.sup.#  .sup. 2.94 ± 0.20.sup.### 0.13 ± 0.03.sup.### calcium group Note: Data are expressed as mean ± standard error, *P < 0.05 vs. blank control group, **P < 0.01 vs. blank control group, ***P < 0.001 vs. blank control group, .sup.#P < 0.05 vs. hyperlipidemia model group, .sup.##P < 0.01 vs. hyperlipidemia model group, .sup.###P < 0.001 vs. hyperlipidemia model group; blank control group, n = 10; hyperlipidemia model group, n = 10; low-dose test object group, n = 10; medium-dose test object group, n = 10; high-dose test object group, n = 10; atorvastatin calcium group: positive control drug group, n = 11.

(102) The results are shown in Table 5 and FIG. 8. Two weeks after administration, compared with rats in the blank control group, rats in the mixed hyperlipidemia model group have significantly increased TC (*** P<0.001 vs. blank control group) and TG (*** P<0.001 vs. blank control group) in liver, thus determining the successful establishment of the model. Emodin succinyl ethyl ester in low, medium, high doses and atorvastatin calcium can reduce TC (.sup.#P<0.05 vs. hyperlipidemia model group) and TG (.sup.##P<0.01 vs. hyperlipidemia model group); emodin succinyl ethyl ester shows good effects of lowering blood lipid and protecting the liver, so it can be used for prevention or treatment of fatty liver.

(103) TABLE-US-00005 TABLE 5 Effect of emodin succinyl ethyl ester on the levels of TC and TG in the liver of rats with mixed hyperlipidemia Group TC (mmol/L) TG (mmol/L) Blank control 0.027 ± 0.004.sup.  0.073 ± 0.008 .sup.  group Hyperlipidemia  .sup. 0.137 ± 0.052**  0.206 ± 0.038*** mode group Low-dose test 0.069 ± 0.010.sup.# 0.105 ± 0.023.sup.### object group Medium-dose test 0.078 ± 0.010.sup.# 0.127 ± 0.016.sup.##  object group High-dose test .sup. 0.059 ± 0.005.sup.## 0.079 ± 0.011.sup.### object group Atorvastatin 0.066 ± 0.004.sup.# 0.090 ± 0.008.sup.##  calcium group Note: Data are expressed as mean ± standard error, *P < 0.05 vs. blank control group, **P < 0.01 vs. blank control group, ***P < 0.001 vs. blank control group, .sup.#P < 0.05 vs. hyperlipidemia model group, .sup.##P < 0.01 vs. hyperlipidemia model group, .sup.###P < 0.001 vs. hyperlipidemia model group; blank control group; hyperlipidemia model group; low-dose test object group; medium-dose test object group; high-dose test object group; and atorvastatin calcium group: positive control drug group, n = 5.

Example 7 Efficacy Test 3 of the Product of the Present Invention

(104) 1. Experimental Materials

(105) Experimental animals: 51 rats of uniform weight

(106) Test object: Emodin succinyl ethyl ester (prepared in Examples 1-3)

(107) High-fat feed: 20.0% of sucrose, 15% of lard, 1.2% of cholesterol, 0.2% of sodium cholate, an appropriate amount of casein, calcium hydrogen phosphate, stone powder, etc. were added to the maintenance feed. In addition to crude fat, the moisture, crude protein, crude fat, crude fiber, crude ash, calcium, and phosphorus of the model feed must meet the national standards for maintenance feed. The feed is clean grade, vacuum packed and stored at room temperature.

(108) 2. Experimental Principle

(109) Feeding rats with high-fat feed containing cholesterol, sucrose, lard and sodium cholate can form a rat model of lipid metabolism disorders and then the rats are administered with a drug, detect the effects of the test object on hyperlipidemia, and determine the effect of the test object on the lipid absorption, lipoprotein formation, lipid degradation or excretion in rats.

(110) Determination of mixed hyperlipidemia rat model: After the end of the modeling period, compared with the blank control group, rats in the hyperlipidemia model group had increased TG, TC or LDL-C in the serum, and the differences were significant, thus the establishment of the model determined.

(111) 3. Experimental Methods

(112) 3.1 Animal Grouping

(113) First random grouping: After the animals are received, they are adaptively fed for 5 to 7 days. During the domestication period, the appearance and general state of the rats are observed. Only qualified rats can enter this experiment. After the end of the adaptation period, the rats were weighed and randomly divided into a blank control group (10 rats) and a hyperlipidemia model group (41 rats).

(114) Second random grouping: After the establishment of the rat hyperlipidemia model, the blood lipids of the rats were measured, and rats in the hyperlipidemia model group were randomly divided into four groups, 11 rats in the positive drug group, 10 rats in each of the other groups. The four groups were the hyperlipidemia model group, the low-dose test object (emodin succinyl ethyl ester in a dose of 20 mg/kg.Math.d.sup.−1) group, the emodin (20 mg/kg.Math.d.sup.−1) group, and the positive control drug (Atorvastatin calcium group in a dose of 10 mg/kg.Math.d.sup.−1) group, respectively.

(115) 3.2 Establishment Period of Mixed Hyperlipidemia Model

(116) The administration and diet of the animals in each group are shown in Table 6. In the experimental groups, rats in the blank control group were fed with maintenance feed and the remaining 4 groups were fed with a high-fat diet. After 2 weeks, the levels of TG, TC, LDL-C and HDL-C in the serum of the rats were measured. The rats were weighed once a week.

(117) Two weeks after the rats in the hyperlipidemia model group were given a high-fat diet, rats in the blank control group and the hyperlipidemia model group were not fasted to take blood from the tip of the tail. The serum was then separated and the levels of TC, TG, LDL-C and HDL-C in the serum were measured. According to the levels of TC, TG and LDL-C, the rats in the hyperlipidemia model group were randomly divided into 4 groups. After grouping, the hyperlipidemia model group, the test object (emodin succinyl ethyl ester in a dose of 20 mg/kg.Math.d.sup.−1) group, the emodin (20 mg/kg.Math.d.sup.−1) group, and the positive control drug (Atorvastatin calcium group in a dose of 10 mg/kg.Math.d.sup.−1) group were compared with the blank control group in terms of TC, TG, LDL-C and HDL-C.

(118) The changes in blood lipids of rats in the hyperlipidemia model group and each administration group, compared with the blank control group, were observed. The results are shown in Table 7 and FIG. 9. After the establishment of the mixed hyperlipidemia model, compared with rats in each administration group and rats in the blank group, the rats in the hyperlipidemia model group had significant increase in TC (*** P<0.001 vs. blank control group) and LDL-C (** P<0.01 vs. blank control group, *** P<0.001 vs. blank control group) in the serum, all with statistical differences, and there was no significant difference in TC and LDL-C among the administration groups. In this case, it could be determined that the mixed hyperlipidemia model was successfully established.

(119) TABLE-US-00006 TABLE 6 Drug administration and diet of animals in each group Admini- Num- Administration stration ber Group frequency cycle Dose Diet of rats Blank control Intragastrically Two 10 ml/kg Normal 10 group administered weeks (rat weight) once a day Hyperlipidemia Intragastrically Two 10 ml/kg High-fat 10 model group administered weeks (rat weight) once a day Test object Intragastrically Two 20 mg/kg High-fat 10 (emodin succinyl administered weeks (rat weight) ethyl ester) once a day group Emodin group Intragastrically Two 20 mg/kg High-fat 10 administered weeks (rat weight) once a day Positive control Intragastrically Two 10 mg/kg High-fat 11 drug group administered weeks (rat weight) once a day

(120) TABLE-US-00007 TABLE 7 Blood lipid level of rats after modeling Group TC (mmol/L) LDL-C (mmol/L) Blank control 1.99 ± 0.35   0.22 ± 0.06   group Hyperlipidemia 3.15 ± 0.61*** 0.41 ± 0.11*** mode group Emodin 3.10 ± 0.37*** 0.37 ± 0.07*** derivative group Emodin group 3.02 ± 0.06*** 0.38 ± 0.09*** Atorvastatin 3.00 ± 0.53*** 0.36 ± 0.10**  calcium group Note: Data are expressed as mean ± standard error, *P < 0.05 vs. blank control group, **P < 0.01 vs. blank control group, ***P < 0.001 vs. blank control group, blank control group, n = 10; hyperlipidemia model group, n = 10; test object (emodin succinyl ethyl ester) group, n = 10; emodin group, n = 10; atorvastatin calcium group, n = 11.

(121) 3.3 Administration Period

(122) The rats in the successfully grouped test object (emodin succinyl ethyl ester) group, emodin group and positive control drug group (atorvastatin calcium group) were intragastrically administered daily. Rats in the blank control group and the hyperlipidemia model group were given corresponding doses of lysozyme. The doses of the groups are shown in Table 6.

(123) Feeding conditions remained unchanged. The rats were weighed once a week. Blood were collected at the tip of the tail two weeks after drug administration. The effect of the test object on the TC, TG, LDL-C and HDL-C in serum of the rats were observed.

(124) 3.4 Observation Period

(125) General vital signs were observed during the experiment.

(126) 3.5 Main Detection Indicators

(127) (1) Weight, measured once a week.

(128) (2) TC, TG, LDL-C and HDL-C in serum, measured once after the establishment of the hyperlipidemia model and two weeks after administration.

(129) 4. Experimental Data and Results

(130) 4.1 Data Processing

(131) The analysis of variance is performed, but the homogeneity of variance test needs to be performed first according to the procedure of analysis of variance. If the variance is homogeneous, the F value is calculated, and 36F<0.05. Conclusion: There is no significant difference between the means of all the groups; F≥0.05, P≤0.05, and the statistics are made using a pairwise comparison of means between multiple experimental groups and one control group; appropriate variable conversion is performed on non-normal or heterogeneous-variance data; after the data after conversion become normal and homogeneous-variance data, the data are used for statistics; if the data after conversion still are non-normal and heterogeneous-variance data, rank sum test could be performed for statistics.

(132) 4.2 Determination of Animal Experiment Results

(133) Determination of lipid-lowering effect: Compared with the blank control group, rats in the hyperlipidemia model control group had increased TG, TC or LDL-C in the serum, and the differences were significant, thus the establishment of the model is determined.

(134) (1) Compared with the model control group, rats in the test object group had reduced TC or LDL-C in serum and the rats in the test object group had reduced TG, with significant differences; moreover, the level of HDL-C in serum of rats in the test object group was not significantly lower than that in the model control group; thus, it could be determined that the test sample had a positive result in the animal experiment on blood lipid lowering function.

(135) (2) Compared with the model control group, rats in the test object group had reduced TC or LDL-C in serum, with significant differences; moreover, the TG in serum of rats in the test object group was not significantly higher than that in the model control group, and the level of HDL-C in serum of rats in the test object group was not significantly lower than that in the model control group; thus, it could be determined that the test sample had a positive result in the animal experiment on cholesterol lowering function.

(136) (3) Compared with the model control group, rats in the test object group had reduced TG in serum, with significant differences; moreover, the TC and LDL-C in serum of rats in the test object group were not significantly higher than those in the model control group, and the level of HDL-C in serum of rats in each dose group was not significantly lower than that in the model control group; thus, it could be determined that the test sample had a positive result in the animal experiment on TG lowering function.

(137) 4.3 Experimental Results

(138) The results are shown in FIG. 10. Two weeks after administration, compared with rats in the blank control group, rats in the mixed hyperlipidemia model group have significantly increased TC (*** P<0.001 vs. blank control group) and LDL-C (*** P<0.001 vs. blank control group) in serum, thus determining the successful establishment of the model. The test object (emodin succinyl ethyl ester in a dose of 20 mg/kg.Math.d.sup.−1) can significantly reduce TC (.sup.#P<0.05 vs. hyperlipidemia group) and LDL-C (.sup.#P<0.05 vs. hyperlipidemia group) in serum of rats with hyperlipidemia, and it is obvious that the test object (emodin succinyl ethyl ester in a dose of 20 mg/kg.Math.d.sup.−1) has better effects of lowering TC (.sup.&P<0.05 vs. emodin group) and LDL-C (.sup.&P<0.05 vs. emodin group) in serum of rats than the equivalent dose of emodin (20 mg/kg.Math.d.sup.−1).

Example 8 Efficacy Test 4 of the Product of the Present Invention

(139) 1. Experimental Materials

(140) Experimental cells: HepG2 cell line

(141) Test object: Emodin succinyl ethyl ester (prepared in Examples 1-3)

(142) 2. Experimental Principle

(143) Oleic acid is added to culture HepG2 cells to induce a hyperlipemia cell model, and then the cells are given a test drug, the effect of the test object on the lipid level of the cells is detected.

(144) 3. Experimental Methods

(145) 3.1 Cell Grouping

(146) When the degree of cell fusion reached about 80%, except for the normal group, cells in other groups were all added with oleic acid at a dose of 200 μmol/L, and then the cells were divided into five groups: the normal group, the oleic acid-induced hyperlipemia group, low-dose emodin succinyl ethyl ester group (5 μmol/L), the medium-dose emodin succinyl ethyl ester group (10 μmol/L) and the high dose emodin succinyl ethyl ester group (20 μmol/L). 24 hours later, the levels of TC and TG were measured.

(147) 3.2 Test Methods

(148) 3.2.1 Cell Collection:

(149) The cells were digested with 0.25% trypsin to prepare a cell suspension; the cell suspension was centrifuged at 1000 rpm for 10 minutes; the supernatant was discarded, and the cell pellet was collected, washed with PBS once or twice, and configured at 1000 rpm for 10 minutes; the supernatant was discarded, and the cell pellet was collected.

(150) 3.2.2 Cell Disruption:

(151) 200 μl of 2% TritonX-100 was added for lysis for 30 minutes.

(152) 3.2.3 Determination Method

(153) First, the protein concentration of the sample was determined using the Beyotime kit. Then, 250 μl of working solution was added to a 96-well plate, 2.5 μl of distilled water was added to the blank wells, 2.5 μl of calibration solution was added to the calibration wells, 2.5 μl of sample was added to the sample wells, and they were all incubated for 10 minutes at 37° C. The OD values were measured by using a 510 nm microplate reader.

(154) 3.2.4 Calculation Formulas:
Cholesterol content=(sample OD value−blank OD value)/(calibrated OD value−blank OD value)*5.17/protein concentration of the sample to be tested
Triglyceride content=(sample OD value−blank OD value)/(calibrated OD value−blank OD value)*2.26/protein concentration of the sample to be tested.

(155) 4. Experimental Data and Results

(156) 4.1 Data Processing

(157) The analysis of variance is performed, but the homogeneity of variance test needs to be performed first according to the procedure of analysis of variance. If the variance is homogeneous, the F value is calculated, and 36F<0.05. Conclusion: There is no significant difference between the means of all the groups; F≥0.05, P≤0.05, and the statistics are made using a pairwise comparison of means between multiple experimental groups and one control group; appropriate variable conversion is performed on non-normal or heterogeneous-variance data; after the data after conversion become normal and homogeneous-variance data, the data are used for statistics; if the data after conversion still are non-normal and heterogeneous-variance data, rank sum test could be performed for statistics.

(158) 4.2 Experimental Results

(159) The effect of emodin succinyl ethyl ester on the levels of TC and TG in oleic acid-induced hyperlipemia cells is shown in Table 8 and FIG. 11. From the results, it can be seen that the levels of TC (*** P<0.001 vs. blank control group) and TG (*** P<0.001 vs. blank control group) of oleic acid-induced hyperlipemia cells are significantly increased as compared with those of the blank control group, thus determining the successful establishment of the model. Emodin succinyl ethyl ester in low, medium, and high doses can significantly reduce the levels of TC (.sup.###P<0.001 vs. oleic acid group) and TG (.sup.#P<0.05 vs. oleic acid group) of oleic acid-induced hyperlipemia cells.

(160) TABLE-US-00008 TABLE 8 Effect of emodin succinyl ethyl ester on the levels of TC and TG in oleic acid-induced hyperlipemia cells Group TC (mmol/L) TG (mmol/L) Blank control group 0.175 ± 0.080    0.125 ± 0.119.sup.  Oleic acid group 1.000 ± 0.000***.sup.   .sup. 1.000 ± 0.000*** Low-dose emodin 0.730 ± 0.168.sup.##   0.610 ± 0.308.sup.# succinyl ethyl ester group Medium-dose emodin 0.506 ± 0.197.sup.###&  0.487 ± 0.347.sup.# succinyl ethyl ester group High-dose emodin 0.537 ± 0.145.sup.###&& .sup. 0.414 ± 0.209.sup.## succinyl ethyl ester group Note: Data are expressed as mean ± standard error, ***P < 0.001 vs. blank control group, *P < 0.05 vs. oleic acid group, .sup.##P < 0.01 vs. oleic acid group, .sup.###P < 0.001 vs. oleic acid group, blank control group, n = 6; oleic acid group, n = 6; low-dose test object (emodin succinyl ethyl ester in a dose of 5 μmol/L) group, n = 6; medium-dose test object (emodin succinyl ethyl ester in a dose of 10 μmol/L) group, n = 6; high-dose test object (emodin succinyl ethyl ester in a dose of 20 μmol/L) group, n = 6.

(161) The above are only the preferred embodiments of the present invention. It should be noted that, for those of ordinary skill in the art, without departing from the principles of the present invention, several improvements and retouches can be made, and these improvements and retouches should also be regarded as falling within the scope off the present invention.