A glutinous rice fragrance extract, preparation method and application thereof

Abstract

The present invention belongs to the field of medicine / product technology, and relates to a glutinous rice fragrance extract, a preparation method and application thereof. The method comprises the following steps: the dried above-ground part of glutinous rice fragrance is crushed, and then an ethanol aqueous solution with a mass fraction of 95% is added and extracted at room temperature for 3 times, and the extraction time is 8 days, 7 days, and 6 days respectively, and the weight ratio of the ethanol aqueous solution added to the glutinous rice fragrance is 12 L: 1 kg each time, and the extracts of each time are combined and concentrated under reduced pressure to obtain an extract of glutinous rice fragrance, which is glutinous rice fragrance extract A, and the extract is extracted with ethyl acetate, and the extracts B and C are obtained by chromatography on D101 macroporous resin and MCI cation exchange chromatography column. Glutinous rice fragrance extract A-C significantly inhibits the synthesis of triglycerides in pre-adipocytes, has good anti-obesity efficacy in a high-fat diet-induced obese mouse model, improves glucose tolerance damage caused by a high-fat diet, has no toxic side effects, and has a simple preparation process.

Description

Technical Field

[0001] The invention belongs to the technical field of medicines, and particularly relates to a glutinous rice fragrance extract, a preparation method thereof and application thereof in lipid-lowering and weight-loss. Background Art

[0002] Obesity is a metabolic disease characterized by excessive accumulation of body fat and abnormal body weight, and has become the world's largest chronic disease.

[0003] Excessive obesity and obesity-related complications, including type 2 diabetes, cardiovascular disease, osteoarthritis, obstructive sleep apnea and various cancers, are one of the leading causes of illness and death worldwide. As the global obesity problem continues to worsen, weight loss has become a focus of attention for many people. Currently, the weight loss drugs approved for marketing in my country, such as orlistat, semaglutide and liraglutide, have many adverse reactions, mainly including increased flatulence, urgent bowel movements, steatorrhea, frequent bowel movements, fecal incontinence, rectal discomfort, abdominal discomfort, etc., so there is an urgent need to develop effective and low-toxic weight loss drugs. In recent years, traditional Chinese medicine anti-obesity drugs have gradually been favored by researchers. Many Chinese herbal medicine molecules have shown potential anti-obesity activity, such as Leguminosae, Campanulaceae, Oleaceae, Zingiberaceae, Araliaceae, Solanaceae, Nelumboceae and Theaceae. A large number of anti-obesity active small molecules have been extracted from these plants, and they show a variety of different anti-obesity mechanisms.

[0004] Glutinous rice fragrance (Latin name Strobilanthes tonkinensis ), belonging to the genus of the family Acanthaceae, is only distributed in Yunnan Province, my country. It has a delicate aroma, a pure and refreshing taste, and a unique glutinous rice fragrance. It has the health benefits of nourishing yin and kidney, anti-aging and beauty, cooling and relieving heat, and helping digestion and sobering up. So far, there has been no research on the lipid-lowering and anti-obesity effects of glutinous rice extract, resulting in unclear material basis and mechanism of action of its efficacy. Summary of the invention

[0005] Technical issues

[0006] Currently, there are still many adverse reactions in the weight loss-related drugs approved for marketing in my country, so there is an urgent need to develop effective, low-toxic anti-obesity drugs. This application prepares the effective extract of Nuomixiang and evaluates its efficacy in weight loss, lipid-lowering and related metabolic diseases.

[0007] Technical Solution

[0008] One object of the present invention is to provide a method for preparing a glutinous rice fragrance extract. The extract obtained by the method has significant effects in lowering lipids and resisting obesity, and can also improve glucose tolerance damage, alleviate insulin resistance, and improve insulin sensitivity.

[0009] Another object of the present invention is to provide a glutinous rice-flavored extract prepared using the preparation method.

[0010] Another object of the present invention is to provide the application of the glutinous rice fragrance extract.

[0011] According to one embodiment of the present invention, a method for preparing a glutinous rice flavor extract A is disclosed, and the method comprises the following steps:

[0012] (1) The dried aerial part of the glutinous rice fragrance was crushed and then extracted with 95% ethanol aqueous solution at room temperature for three times. The extraction times were 8 days, 7 days, and 6 days, respectively. The weight ratio of ethanol aqueous solution added to glutinous rice fragrance was 12 L:1 kg each time. The extracts from each time were combined and concentrated under reduced pressure to obtain the extract of glutinous rice fragrance, which was glutinous rice fragrance extract A.

[0013] According to one embodiment of the present invention, the method further comprises:

[0014] (2) suspending and dissolving the extract with distilled water of 5 times the volume of the extract, and then extracting with ethyl acetate of 1.5 times the volume of the extract, combining the organic phase extracts and concentrating under reduced pressure to recover ethyl acetate, thereby obtaining an ethyl acetate extract of glutinous rice fragrance;

[0015] (3) Using a D101 macroporous resin column, the ethyl acetate extract in step (2) was segmented and gradient eluted with ethanol-water mixed solvents of 30%, 80% and 95% by volume, respectively, and the eluents of corresponding proportions were collected and concentrated under reduced pressure to remove the solvent to obtain three elution components: 30% ethanol macroporous phase, 80% ethanol macroporous phase, and 95% ethanol macroporous phase;

[0016] The 80% ethanol macroporous phase was used as the glutinous rice fragrance extract B.

[0017] Among them, the 30% ethanol macroporous phase and the 95% ethanol macroporous phase have no activity.

[0018] According to one embodiment of the present invention, the method further comprises:

[0019] (4) The 80% ethanol macroporous phase in step (3) was segmented using an MCI cation exchange column, and gradient eluted with 5% methanol-water by volume to 100% methanol-water, and nine subfractions NMX-A1 to NMX-A9 were obtained by thin layer chromatography; NMX-A9 was the 80%-100% methanol-water elution fraction,

[0020] NMX-A9 was used as glutinous rice flavor extract C.

[0021] According to one embodiment of the present invention, a glutinous rice flavor extract A is provided, and the glutinous rice flavor extract A is prepared according to a method comprising the above step (1).

[0022] According to one embodiment of the present invention, there is provided a glutinous rice flavor extract B, which is prepared according to a method comprising the above steps (1) to (3).

[0023] According to one embodiment of the present invention, a glutinous rice flavor extract C is provided. The glutinous rice flavor extract C is prepared according to a method comprising steps (1) to (4) above.

[0024] According to one embodiment of the present invention, it provides the use of the glutinous rice fragrance extract in preparing products for preventing or treating obesity and reducing lipids.

[0025] According to one embodiment of the present invention, it provides the use of the glutinous rice fragrance extract in preparing a product for preventing or treating diabetes.

[0026] According to one embodiment of the present invention, it provides the use of the glutinous rice fragrance extract in the preparation of a product for preventing or treating glucose tolerance impairment or insulin resistance.

[0027] Beneficial Effects

[0028] The extract of the invention has good lipid-lowering and anti-obesity effects, improves glucose tolerance damage caused by a high-fat diet, has no toxic side effects, and has a simple and easy process. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The invention discloses a method for preparing glutinous rice flavor extracts NMX-YC, NMX-80% and NMX-A9, wherein NMX-A9 is obtained by separation of D101 macroporous resin and MCI cation exchange resin.

[0030] Figure 2 Oil red O staining images of the effects of undifferentiated control group, differentiated control group (blank control), and different concentrations of different glutinous rice extracts on triglyceride content in mouse preadipocytes 3T3-L1.

[0031] Figure 3 These are the results of determining the triglyceride content in mouse preadipocytes 3T3-L1 in the undifferentiated control group, differentiated control group (blank control), and different concentrations of different glutinous rice extract fractions.

[0032] Figure 4 The effects of glutinous rice extracts NMX-YC (A), NMX-80% (B) and NMX-A9 (C) on the body weight of obese mice induced by high-fat diet (HFD) over time, **P<0.01, ***P<0.001,### P<0.001.

[0033] Figure 5 The statistical results of daily food intake of experimental mice in different groups, NS means not significant.

[0034] Figure 6 Oil red O and H&E staining images of liver, abdominal adipose tissue and kidney tissue sections of HFD-induced obese mice treated with NMX-YC (A), NMX-80% (B) and NMX-A9 (C).

[0035] Figure 7 The results show that NMX-YC, NMX-80% and NMX-A9 reduce the changes of serum triglycerides in HFD-induced obese mice. *P<0.05, **P<0.01, ***P<0.001, NS means not significant.

[0036] Figure 8 The changes of serum cholesterol in HFD-induced obese mice treated with NMX-YC, NMX-80% and NMX-A9, *P<0.05, ***P<0.001, NS means not significant.

[0037] Fig. 9 The changes of glucose tolerance (OGTT) in HFD-induced obese mice were observed by NMX-YC (A), NMX-80% (B) and NMX-A9 (C).

[0038] Fig.10 The changes of insulin sensitivity (ITT) in HFD-induced obese mice were observed by NMX-YC (A), NMX-80% (B) and NMX-A9 (C). DETAILED DESCRIPTION

[0039] The following specific examples are used to further illustrate the preparation steps and pharmacological experimental process of the effective part of the extract of the present invention. It should be understood that the following examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. Those skilled in the art can make various modifications and changes to this, and the attached claims cover all these modifications within the scope of the present invention without departing from the spirit and scope of the present invention.

[0040] In the present invention, the glutinous rice fragrance used is from Xishuangbanna, Yunnan, the reagents used such as ethanol and ethyl acetate are purchased from Tianjin Fuyu Fine Chemical Co., Ltd., the D101 macroporous resin and MCI cation exchange chromatography column used are purchased from Titan Technology Exploration Platform, and unless otherwise specified, the raw materials used in the biological activity experiment are purchased from Titan Technology Exploration Platform, and the instruments are purchased from Titan Technology Exploration Platform.

[0041] Abbreviations: MTT: Thiazolyl blue; DMSO: dimethyl sulfoxide; OD: absorbance; DMEM: Dulbecco's modified Eagle's medium.

[0042] Example 1

[0043] Preparation method of glutinous rice fragrance extract of the present invention

[0044] 1. Glutinous rice extract (ethanol extract)

[0045] The powder (10 kg) of the above-ground part of the collected medicinal plant Nian Mi Xiang was dried and crushed, and extracted with 120 L of 95% ethanol aqueous solution at room temperature for 3 times (8 days, 7 days and 6 days respectively), condensed and refluxed, and the ethanol was evaporated under reduced pressure to obtain the extract NMX-YC (758.0 g);

[0046] 2. Glutinous rice extract (80% ethanol macroporous phase)

[0047] The extract NMX-YC was suspended in distilled water 5 times the volume of the extract, and extracted and distributed with ethyl acetate 1.5 times the volume of the extract, and the organic phase extracts were combined and concentrated under reduced pressure to recover ethyl acetate, and ethyl acetate extract NMX-YS (180 g) was obtained. The extract was chromatographed on a D101 macroporous resin column with a gradient elution of ethanol-water mixed solvents with a volume ratio of 30%, 80% and 95%, and concentrated under reduced pressure to obtain three elution components, 30% ethanol macroporous phase NMX-30% (2.5 g), 80% ethanol macroporous phase NMX-80% (38.0 g), and 95% ethanol macroporous phase NMX-95% (36.5 g).

[0048] The 80% ethanol macroporous phase NMX-80% was used as the glutinous rice fragrance extract;

[0049] 3. Glutinous rice extract (NMX-A9)

[0050] The 80% ethanol macroporous phase NMX-80% was eluted with a MCI cation exchange column by a gradient elution of 5%-100% methanol-water to obtain NMX-A1 to A9, of which NMX-A1 to NMX-A4 were fractions eluted with 5%-40% methanol-water, NMX-A5 to NMX-A8 were fractions eluted with 50%-70% methanol-water, and NMX-A9 (12.3 g) was fractions eluted with 80%-100% methanol-water. The brief operation process is as follows: Figure 1 shown.

[0051] NMX-A9 was used as the glutinous rice flavor extract.

[0052] Example 2

[0053] Cytotoxicity test of 3T3-L1 preadipocytes

[0054] When the density of 3T3-L1 preadipocytes reaches 80%-90%, the cells are plated. 5000 cells are inoculated into each well of a 96-well plate, and the culture system is 100 µ L. After culturing for 24 h to 36 h, 8 groups of drug administration were set up after the cells attached to the wall, that is, high concentration (12.5 µ g / mL) and low concentrations (6.25 µ g / mL) ethanol phase (NMX-YC), 80% ethanol macroporous phase (NMX-80%) and MCI-A9 subfraction (NMX-A9). A blank control group (wells containing cells with 0 dosing, the cell viability of this group in the experiment was taken as 100%) was set up. After 48 h of dosing, 0.5 mg / mL MTT was given, incubated at 37 °C for 4 h, and then an equal volume of DMSO was added to dissolve the formazan precipitate, and the OD was measured. 570 Absorbance value. The inhibition rate of the drug-added group compound = 1-OD value of the drug-added group / OD value of the control group. Finally, set up gradient concentration rescreening and use Graphpad software to calculate the half-inhibitory concentration IC 50 The values ​​are shown in the following table:

[0055] Table 1 Toxicity of three extracts of Nuomixiang to 3T3-L1 cells

[0056]

[0057] From IC 50 The test data results showed that the three glutinous rice extracts had basically no cytotoxicity to 3T3-L1 cells.

[0058] Example 3

[0059] Lipid-lowering activity test of 3T3-L1 preadipocytes

[0060] (1) Culture medium and reagents used in the experiment:

[0061] Basic culture medium: DMEM high glucose containing 10% fetal bovine serum and 1% penicillin-streptomycin.

[0062] Cell differentiation induction solution I: 500 µ M 3 -isobutyl-1-methylxanthine (IBMX), 100 ng / mL dexamethasone, 2 µ g / mL insulin, 1 µ M DMEM medium containing rosiglitazone, 10% fetal bovine serum, and 1% p / s.

[0063] Cell differentiation induction solution II: contains 2 µg / mL insulin, 10% fetal bovine serum and 1% p / s in DMEM medium.

[0064] (2) Experimental group settings:

[0065] 3T3-L1 cells in the logarithmic growth phase were plated, 20,000 cells were inoculated in each well of a 48-well plate, and cultured in basal medium at 5% CO2 and 37 °C; when the cells grew to 100% complete confluence, an undifferentiated control group (UND), a differentiated control group (Vehicle) and a drug-treated group (a total of 8 drug treatments) were set up and cultured for 9 days respectively.

[0066] Undifferentiated control group (UND): The cells were cultured with basal medium from day 1 to day 9, and the medium was changed every three days.

[0067] Differentiation control group: on days 1-3, use cell differentiation induction solution I; on days 4-6, use cell differentiation induction solution II; on days 7-9, use basal culture medium.

[0068] Drug treatment group: On days 1-3, cells were treated with different concentrations of cell differentiation induction solution I (20, 10, 5, 2.5, 1.25, 0.63, 0.31, 0.15 µ M) of the compound (drug solution); on days 4-6, cells were cultured with different concentrations of cell differentiation induction solution II (20, 10, 5, 2.5, 1.25, 0.63, 0.31, 0.15 µ M) of the compound (drug solution) to culture cells; on days 7-9, different concentrations (20, 10, 5, 2.5, 1.25, 0.63, 0.31, 0.15 µ M) Compound (drug solution) cultured cells.

[0069] The above cultures were performed twice, one group of cells was used for Oil Red O staining experiment, and the other group of cells was used to determine the content of triglyceride (TG).

[0070] (3) Oil Red O staining:

[0071] After the culture was completed, the upper layer of culture medium was discarded, and the cells were gently rinsed with 1×PBS, and fixed with 4% paraformaldehyde at room temperature for more than 30 min. The upper layer of liquid was then aspirated, and 0.3% Oil Red O staining solution was added to stain for 30 min in the dark. After that, the cells were gently rinsed with tap water, and appropriate amount of deionized water was added. Microscopic photos were taken to obtain the Oil Red O staining micrographs of each group, as shown in the figure. Figure 2 shown.

[0072] (4) Quantitative detection of triglycerides (TG):

[0073] After the cell culture was completed, the culture medium was discarded, the cells were gently washed once with PBS, and 50 µ L of 2% Triton X-100 (diluted with ddH2O) and lyse for 40-60 min until the cells are completely lysed. Take a 96-well plate and add 200 μL of 2% Triton X-100 to each well. µ L of TG working solution, and then add 10 µ L cell samples and 2 µ L standard. Set up a blank group and add 200 µ L working solution and 10 µ 1 L of 2% Triton X-100, mix well. Incubate at 37 °C for 10-15 min and measure OD 510 Absorbance value. The protein concentration of the cell sample was measured with the BCA protein quantification kit, and the TG content was calculated according to the following formula (the standard concentration was 2.26 mmol / L). Where: TG content (mmol / gprot) = [(sample OD value − blank OD value) / (calibrator OD value − blank OD value)] × calibration concentration (mmol / L) ÷ protein concentration of the sample to be tested (gprot / L). The TG content of each group is as follows Figure 3 Finally, set up gradient concentration rescreening and use Graphpad software to calculate EC 50 Value (concentration that inhibits 50% of the maximum effect of triglycerides), the calculation results are shown in the following table:

[0074] Table 2 Lipid-lowering activity of three extracts of Nuomixiang on 3T3-L1 cells

[0075]

[0076] From EC 50 The test data showed that the three kinds of glutinous rice extracts can significantly reduce the triglyceride content in mouse preadipocytes 3T3-L1, among which NMX-A9 has the best lipid-lowering activity, EC 50 The value is 18.38±3.00 µ g / mL.

[0077] Example 4

[0078] In vivo evaluation of anti-obesity activity

[0079] Thirty C57BL / 6 mice were randomly divided into five groups (6 mice in each group) after one week of adaptive feeding: normal diet group, obesity model group (high-fat diet, HFD diet), positive drug control group (orlistat, HFD + Orlistat, 40 mg / kg), and two HFD + NMX-YC, NMX-80% and NMX-A9 administration groups (high dose: 120 mg / kg and low dose: 40 mg / kg).

[0080] Each group of mice was given free access to water, the normal diet group was given maintenance feed, and the other groups were given 60% high-fat feed for 8 weeks (at this time, the average weight of mice in the high-fat diet group exceeded that of the normal diet group by more than 20%). After 8 weeks, the fraction administration group and the positive drug control group were gavaged (the gavage volume was calculated as 0.2 mL / 10g, and the drug was prepared with 0.5% CMC-Na) and the NMX-YC, NMX-80% and NMX-A9 (high dose: 120 mg / kg and low dose: 40 mg / kg) prepared in Example 1 and the positive drug Orlistat (Orlistat, 40 mg / kg) were administered once every two days, and glucose tolerance test (GTT) and insulin sensitivity test (ITT) were performed during the experiment. During the whole experiment, the normal diet group and the obesity model group were gavaged with an equal volume of 0.5% CMC-Na solution as the experimental control.

[0081] (1) Analysis of body weight and food intake:

[0082] The weight and food intake of mice were recorded from the first day after administration. The weight change data over time are as follows: Figure 4 The daily food intake data of mice are shown in Figure 5 shown.

[0083] The data results show that under the condition that the daily food intake of experimental mice is basically the same, the active extracts NMX-YC, NMX-80% and NMX-A9 can significantly reduce the body weight of obese mice induced by high-fat diet (HFD). The weight loss effect of the high-dose group (120 mg / kg) is equivalent to that of the positive control group (orlistat). After 40 days of administration, the body weight of mice decreased by 28.1%.

[0084] (2) Oil Red O staining and H&E staining:

[0085] The liver, abdominal fat and kidney were sliced ​​and stained with Oil Red O and H&E. The staining results were as follows: Figure 6 As shown in Figures A to C, Oil Red O staining was used to observe the accumulation of liver fat, and HE staining was used to observe the morphology and number of adipocytes.

[0086] The data results show that the active extracts NMX-YC, NMX-80% and NMX-A9 can reduce liver fat accumulation in a dose-dependent manner (fat is red in Oil Red O staining) and reduce the volume of adipocytes in adipose tissue (H&E staining). In addition, the active extracts NMX-YC, NMX-80% and NMX-A9 have little damage to liver and kidney cells (H&E staining), so NMX-YC, NMX-80% and NMX-A9 have no hepatotoxicity or renal toxicity.

[0087] (3) Biochemical index detection of triglyceride (TG) and cholesterol (TC) content in blood:

[0088] The mice were fasted for 6 h before the end of the animal experiment. Blood was collected by removing the eyeballs and stored in 1.5 mL centrifuge tubes on ice. The tubes were centrifuged at 4 °C, 3000 rpm / min for 15 min and the supernatant was collected. The triglyceride (TG) content in the blood was detected as follows: Figure 7 As shown, the cholesterol (TC) content is Figure 8 shown.

[0089] The data results show that the active extracts NMX-YC, NMX-80% and NMX-A9 can reduce the blood triglyceride and blood cholesterol concentrations of obese mice, bringing them close to the blood lipid and blood cholesterol levels of normal mice.

[0090] (4) Testing of other blood biochemical indicators:

[0091] As with the above treatment, mouse blood was collected in 1.5 mL sodium heparin anticoagulant tubes and stored on ice. Centrifuged at 4°C, 3000 rpm / min for 15 minutes, the supernatant was retained, and the centrifugation was repeated once. The levels of liver function indicators aspartate aminotransferase (AST) and alanine aminotransferase (ALT), renal function indicators creatinine (CREA) and urea nitrogen (UREA) in the blood were detected using a biochemical automatic analyzer to evaluate the in vivo toxicity of the compound. The results are shown in Table 3 below:

[0092] Table 3 Blood biochemical indexes of three extracts of Nuomixiang

[0093]

[0094] The data results showed that the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine (CREA) and urea nitrogen (UREA) in the blood of the active extracts NMX-YC, NMX-80% and NMX-A9 experimental groups were not significantly different from those of the normal diet group, indicating that the active extracts NMX-YC, NMX-80% and NMX-A9 had no obvious liver and kidney toxicity.

[0095] (5) Glucose tolerance test (OGTT):

[0096] After the mice were treated with the compound for 4 weeks, they were fasted overnight. After the mice were treated with 2 g / kg glucose by gavage, the blood glucose levels of the mice were tested at 0, 15, 30, 60, 90, and 120 min, respectively, to detect the changes in glucose tolerance of the mice. The test results are shown in Fig. 9 shown.

[0097] The data results showed that compared with the normal diet group, the fasting blood sugar level of the obese model group was higher, and the blood sugar level increased significantly 15 minutes after oral glucose administration. Over time, the rate of blood sugar reduction in the obese model group was slower than that in the normal diet group, and the lowest blood sugar value reached was higher than that in the normal diet group, indicating that the blood sugar regulation ability of the obese model group mice was poor and glucose tolerance was impaired. The blood sugar change trend of mice in the active extract NMX-YC, NMX-80% and NMX-A9 administration groups was similar to that of the normal diet group, indicating that the active extracts NMX-YC, NMX-80% and NMX-A9 can improve the glucose tolerance damage caused by a high-fat diet.

[0098] (6) Insulin sensitivity test (ITT):

[0099] After the mice were treated with the compound for 5 weeks, they were fasted for 6 h. After each mouse was treated with 0.6 U insulin intraperitoneally, the blood glucose levels of the mice were tested at 0, 15, 30, 60, 90, and 120 min, and the changes in the insulin sensitivity of the mice were tested. The test results are shown in Fig.10 shown.

[0100] The data results showed that compared with the normal diet group, the blood sugar of the obese model group remained at a high level 15 minutes after intraperitoneal injection of insulin. Over time, the rate of blood sugar reduction in the obese model group was slower than that in the normal diet group, and the lowest blood sugar value was higher than that in the normal diet group, indicating that the mice in the obese model group had a certain insulin resistance and poor insulin sensitivity. The blood sugar change trend of mice in the active extract NMX-YC, NMX-80% and NMX-A9 administration groups was similar to that of the normal diet group, indicating that the active extracts NMX-YC, NMX-80% and NMX-A9 can alleviate insulin resistance in obese mice and improve insulin sensitivity.

Claims

1. A method for preparing a glutinous rice flavor extract B, characterized in that: The method comprises the following steps: (1) The dried aerial part of Nuomixiang was crushed and then extracted with 95% ethanol aqueous solution at room temperature for three times. The extraction time was 8 days, 7 days, and 6 days respectively. The weight ratio of ethanol aqueous solution added to Nuomixiang was 12 L: 1 kg each time. The extracts from each time were combined and concentrated under reduced pressure to obtain the extract of Nuomixiang. (2) suspending and dissolving the extract with distilled water of 5 times the volume of the extract, and then extracting with ethyl acetate of 1.5 times the volume of the extract, combining the organic phase extracts and concentrating under reduced pressure to recover ethyl acetate, thereby obtaining an ethyl acetate extract of glutinous rice fragrance; (3) Using a D101 macroporous resin column, the ethyl acetate extract in step (2) was segmented and gradient eluted with ethanol-water mixed solvents of 30%, 80% and 95% by volume, respectively, and the eluents of corresponding proportions were collected and concentrated under reduced pressure to remove the solvent to obtain three elution components: 30% ethanol macroporous phase, 80% ethanol macroporous phase, and 95% ethanol macroporous phase; The 80% ethanol macroporous phase was used as the glutinous rice fragrance extract B.

2. A glutinous rice flavor extract B, characterized in that: The glutinous rice flavor extract B is prepared according to the method of claim 1.

3. A method for preparing a glutinous rice flavor extract C, characterized in that: The method comprises the following steps: (1) The dried aerial part of Nuomixiang was crushed and then extracted with 95% ethanol aqueous solution at room temperature for three times. The extraction time was 8 days, 7 days, and 6 days respectively. The weight ratio of ethanol aqueous solution added to Nuomixiang was 12 L: 1 kg each time. The extracts from each time were combined and concentrated under reduced pressure to obtain the extract of Nuomixiang. (2) suspending and dissolving the extract with distilled water of 5 times the volume of the extract, and then extracting with ethyl acetate of 1.5 times the volume of the extract, combining the organic phase extracts and concentrating under reduced pressure to recover ethyl acetate, thereby obtaining an ethyl acetate extract of glutinous rice fragrance; (3) Using a D101 macroporous resin column, the ethyl acetate extract in step (2) was segmented and gradient eluted with ethanol-water mixed solvents of 30%, 80% and 95% by volume, respectively, and the eluents of corresponding proportions were collected and concentrated under reduced pressure to remove the solvent to obtain three elution components: 30% ethanol macroporous phase, 80% ethanol macroporous phase, and 95% ethanol macroporous phase; (4) The 80% ethanol macroporous phase in step (3) was segmented using an MCI cation exchange column, and gradient eluted with 5% methanol-water by volume to 100% methanol-water, and nine subfractions NMX-A1 to NMX-A9 were obtained by thin layer chromatography; NMX-A9 was the 80%-100% methanol-water elution fraction, NMX-A9 was used as glutinous rice flavor extract C.

4. A glutinous rice flavor extract C, characterized in that The glutinous rice flavor extract C is prepared according to the method according to claim 3.

5. Use of the glutinous rice extract B according to claim 2 or the glutinous rice extract C according to claim 4 in the preparation of lipid-lowering and / or weight-loss products.

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