Ginkgo biloba extract capable of reducing blood sugar and blood fat, preparation and application of ginkgo biloba extract

Abstract

The invention belongs to the technical field of medicines, and provides a ginkgo biloba extract for reducing blood sugar and blood fat, a preparation and application thereof. The ginkgo biloba extract is prepared by the following steps: (1) extraction: taking ginkgo biloba, carrying out wall breaking and crushing, adding ginkgo biloba powder after wall breaking into an ethanol solution for extraction, and recovering a solvent to obtain a ginkgo biloba primary extract; (2) two-phase enzyme hydrolysis system extraction: adding a compound enzyme, ethyl acetate and a K2HPO4 buffer solution into the ginkgo leaf primary extract for enzymolysis, wherein the compound enzyme consists of cellulase and beta-glucosidase; and (3) recovering the solvent from the ethyl acetate phase. The primary extract of the ginkgo leaf powder is subjected to two-phase enzyme hydrolysis system extraction, so that the yield and the content of effective components, namely total flavonoids and total lactones, in the ginkgo leaf extract are effectively improved, and blood glucose and blood lipid can be effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of medicines and relates to a ginkgo leaf extract for lowering blood sugar and lipids, a preparation and an application thereof. Background Art

[0002] Diabetes mellitus (DM) is a metabolic disease characterized by high blood sugar due to insulin secretion defects or insulin action disorders. Its typical clinical manifestations are "polydipsia, polyphagia, polyuria and weight loss". Diabetes blood sugar is well controlled, but the more it is treated, the more complications it will cause, and the more serious it will be. Therefore, diabetes is not terrible, but the complications of diabetes are terrible. Treating diabetes by lowering blood sugar alone can only treat the symptoms but not the root cause.

[0003] Hyperlipidemia, also known as hyperlipoproteinemia, is an independent risk factor for arteriosclerosis. Arteriosclerosis of the heart and brain can lead to coronary heart disease, angina pectoris, myocardial infarction, cerebrovascular accident and other diseases. If the capillaries of the kidneys are blocked due to hardening, it can cause renal failure, leading to refractory hypertension and uremia. When blood lipids are too high, fat will accumulate in the liver to form fatty liver, which can develop into cirrhosis if it worsens over a long period of time. The key to controlling and treating hyperlipidemia is how to block the formation of hyperlipidemia. Taking drugs and health products supplemented with diet therapy and exercise therapy is the best way to treat hyperlipidemia. Drug treatment has the advantage of being effective quickly, but it may not be suitable for all patients with hyperlipidemia. Moreover, the lipid-lowering drugs currently known have more or less effects on liver function, have obvious toxic and side effects, and are very expensive.

[0004] With the improvement of health awareness, people have turned their attention to high blood sugar and high blood lipids to many plants with medicinal and edible effects. Because they are rich in active ingredients, they have significant effects in reducing blood lipids, blood sugar, and improving carotid artery plaques through the regulation of the monarch, minister, assistant and envoy relationship. Chinese invention patent application CN111084850A discloses a ginkgo compound polyphenol plant medicine for treating hyperlipidemia and coronary heart disease and its preparation method, through the rational compounding of components with hypoglycemic and lipid-lowering effects such as ginkgo leaf extract and gardenia fruit oil, to obtain a medicine suitable for people with hyperlipidemia, hyperthrombosis, and atherosclerosis, which can play the role of lowering blood lipids, promoting blood circulation and dissolving thrombus, preventing and treating atherosclerosis, and losing weight. For example, Chinese invention patent CN102670864B effectively combines grape seed extract, ginkgo leaf extract, chitosan oligosaccharide, and chitosan through compounding technology, providing a pharmaceutical composition with strong antioxidant effect and simultaneous treatment of cardiovascular and cerebrovascular diseases and diabetes.

[0005] How to improve the yield of Ginkgo biloba extract and the content of total flavonoids and total lactones in its related active parts to achieve better hypoglycemic and lipid-lowering effects needs to be solved urgently. Summary of the invention

[0006] The present invention aims at the problems existing in the prior art and provides a ginkgo leaf extract for reducing blood sugar and lipids. The extract is obtained by extracting the ginkgo leaf powder alcohol extract by a two-phase enzyme hydrolysis system, which effectively improves the yield of the ginkgo leaf extract and increases the content of total flavonoids and total lactones as effective ingredients. The ginkgo leaf extract of the present invention can effectively reduce blood sugar and lipids.

[0007] The present invention is achieved through the following technical solutions:

[0008] The first aspect of the present invention is to provide a ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0009] (1) Extraction: Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to an ethanol solution for extraction, and the solvent is recovered to obtain a primary ginkgo leaf extract;

[0010] (2) Biphasic enzyme hydrolysis system extraction: Add complex enzyme, ethyl acetate and K2HPO4 buffer solution to the primary extract of ginkgo leaves for enzymatic hydrolysis, wherein the complex enzyme consists of cellulase and β-glucosidase;

[0011] (3) recovering the solvent from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0012] Preferably, the volume concentration of the ethanol solution in step (1) is 70-90%, and the mass volume ratio of ginkgo leaf powder to ethanol solution is 1:6-9.

[0013] Preferably, the extraction temperature in step (1) is 45-65°C, and the extraction is performed 2-3 times, each time for 1-2 hours.

[0014] Preferably, the composite enzyme in step (2) is composed of 1-2 parts of cellulase and 0.1-0.5 parts of β-glucosidase by weight; the amount of the composite enzyme is 1-3wt.% of the ginkgo powder.

[0015] Preferably, the enzymatic hydrolysis temperature in step (2) is 35-40°C, the enzymatic hydrolysis time is 2-3h, and the enzymatic hydrolysis pH is 4-6.

[0016] Preferably, the volume concentration of the K2HPO4 buffer solution in step (2) is 20-30%.

[0017] Preferably, in step (2), the volume ratio of ethyl acetate to K2HPO4 buffer solution is 2-3:1-2.

[0018] The second aspect of the present invention relates to a preparation containing the above-mentioned Ginkgo biloba leaf extract, wherein the preparation further comprises a pharmaceutically acceptable excipient.

[0019] Preferably, the preparation is in the form of tablets, capsules, granules, pastes, pills, oral solutions, injections or suspensions.

[0020] The third aspect of the present invention relates to the use of the above-mentioned Ginkgo biloba extract or a preparation containing the above-mentioned Ginkgo biloba extract in the preparation of a blood sugar and lipid lowering drug.

[0021] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention effectively improves the yield of ginkgo leaf extract and the content of total ketone esters in the extract by extracting the primary extract of ginkgo leaf powder using a two-phase enzyme hydrolysis system. The yield of ginkgo leaf extract is above 40%, and the content of total ketone esters in the ginkgo leaf extract is above 60%, wherein the content of total flavonoids in ginkgo leaf is above 45%, the content of total lactones in ginkgo leaf is above 16%, and the content of ginkgolic acid is less than 3 ppm; (2) The ginkgo leaf extract obtained by the present invention can effectively reduce blood sugar and lipids, and the dosage is small. DETAILED DESCRIPTION

[0022] The following non-limiting examples can enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. The following content is merely an exemplary description of the scope of the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, which should also fall within the scope of the present invention.

[0023] Example 1

[0024] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0025] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to a 75% ethanol solution by volume and extracted twice at 50° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo biloba leaves;

[0026] (2) adding 2 wt.% composite enzyme (composed of 2 parts of cellulase and 0.5 parts of β-glucosidase) of ginkgo leaf powder, ethyl acetate and a K2HPO4 buffer solution with a volume concentration of 20% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of ethyl acetate to K2HPO4 buffer solution is 2:1, the ratio of the added volume (mL) of ethyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 35°C, the enzymolysis time is 3 h, and the enzymolysis pH is 4.7;

[0027] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0028] Example 2

[0029] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0030] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to an 85% ethanol solution by volume and extracted twice at 65° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo leaves;

[0031] (2) adding 3 wt.% composite enzyme (composed of 2 parts of cellulase and 0.5 parts of β-glucosidase) of ginkgo leaf powder, ethyl acetate and a K2HPO4 buffer solution with a volume concentration of 30% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of ethyl acetate to K2HPO4 buffer solution is 3:1, the ratio of the added volume (mL) of ethyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 40°C, the enzymolysis time is 3 h, and the enzymolysis pH is 5.2;

[0032] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0033] Comparative Example 1

[0034] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0035] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to a 75% ethanol solution by volume and extracted twice at 50° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo biloba leaves;

[0036] (2) adding 2 wt.% composite enzyme (composed of 2 parts of pectinase and 0.5 parts of β-glucosidase) of ginkgo leaf powder, ethyl acetate and a K2HPO4 buffer solution with a volume concentration of 20% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of ethyl acetate to K2HPO4 buffer solution is 2:1, the ratio of the added volume (mL) of ethyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 35°C, the enzymolysis time is 3 h, and the enzymolysis pH is 4.7;

[0037] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0038] The difference from Example 1 is that the cellulase in the complex enzyme in step (2) is replaced by pectinase. The rest is the same as Example 1.

[0039] Comparative Example 2

[0040] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0041] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to a 75% ethanol solution by volume and extracted twice at 50° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo biloba leaves;

[0042] (2) adding 2 wt.% cellulase of ginkgo leaf powder, ethyl acetate and K2HPO4 buffer solution with a volume concentration of 20% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of ethyl acetate to K2HPO4 buffer solution is 2:1, the ratio of the added volume (mL) of ethyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 35°C, the enzymolysis time is 3 h, and the enzymolysis pH is 4.7;

[0043] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0044] The difference from Example 1 is that the composite enzyme in step (2) is replaced by a single enzyme consisting of only cellulase. The rest is the same as Example 1.

[0045] Comparative Example 3

[0046] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0047] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to a 75% ethanol solution by volume and extracted twice at 50° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo biloba leaves;

[0048] (2) adding 2 wt.% β-glucosidase composition of ginkgo leaf powder, ethyl acetate and K2HPO4 buffer solution with a volume concentration of 20% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of ethyl acetate to K2HPO4 buffer solution is 2:1, the ratio of the added volume (mL) of ethyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 35°C, the enzymolysis time is 3h, and the enzymolysis pH is 4.7;

[0049] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0050] The difference from Example 1 is that the composite enzyme in step (2) is replaced by a single enzyme consisting of only β-glucosidase. The rest is the same as Example 1.

[0051] Comparative Example 4

[0052] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0053] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to a 75% ethanol solution by volume and extracted twice at 50° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo biloba leaves;

[0054] (2) adding 2 wt.% composite enzyme (composed of 2 parts of cellulase and 0.5 parts of β-glucosidase) of ginkgo leaf powder, propyl acetate and a K2HPO4 buffer solution with a volume concentration of 20% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of propyl acetate to K2HPO4 buffer solution is 2:1, the ratio of the added volume (mL) of propyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 35°C, the enzymolysis time is 3 h, and the enzymolysis pH is 4.7;

[0055] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the propyl acetate phase to obtain the ginkgo leaf extract.

[0056] The difference from Example 1 is that the ethyl acetate in step (2) is replaced by propyl acetate. The rest is the same as Example 1.

[0057] Comparative Example 5

[0058] A ginkgo leaf extract for lowering blood sugar and lipids, wherein the ginkgo leaf extract is prepared by the following steps:

[0059] (1) Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to a 75% ethanol solution by volume and extracted twice at 50° C., the solid-liquid ratio of the ginkgo powder mass g to the volume mL of the ethanol solution is 1:8 for the first extraction, the extraction is performed for 2 h, the filter residue is subjected to a second extraction, the solid-liquid ratio is 1:6, the extraction is performed for 1 h, the filtrate is combined, and the solvent is recovered to obtain a primary extract of ginkgo biloba leaves;

[0060] (2) adding 2 wt.% composite enzyme (composed of 2 parts of cellulase and 0.5 parts of β-glucosidase) of ginkgo leaf powder, ethyl acetate and a K2HPO4 buffer solution with a volume concentration of 40% to the primary extract of ginkgo leaves for enzymolysis, wherein the volume ratio of ethyl acetate to K2HPO4 buffer solution is 2:1, the ratio of the added volume (mL) of ethyl acetate to the mass (g) of ginkgo leaf powder is 5:1, the enzymolysis temperature is 35°C, the enzymolysis time is 3 h, and the enzymolysis pH is 5.8;

[0061] (3) After the enzymatic hydrolysis is completed, the solvent is recovered from the ethyl acetate phase to obtain the ginkgo leaf extract.

[0062] The difference from Example 1 is that the concentration of the K2HPO4 buffer solution in step (2) is increased from 20% to 40%. The rest is the same as Example 1.

[0063] Comparative Example 6

[0064] Ginkgo leaf extract was prepared according to the method in Example 1 of Chinese invention patent CN102283870B, specifically as follows: 1) extracting ginkgo leaf crude powder with ethanol for 3 times, adding 5 times the amount of 95% ethanol for the first time and soaking for 0.5 hours and then refluxing for extraction for 3 hours, adding 3 times the amount of 90% ethanol for the second time and extracting for 2 hours, adding 2 times the amount of 90% ethanol for the third time and extracting for 2 hours, filtering, recovering ethanol under reduced pressure until there is no alcohol taste, and concentrating to contain 1g / ml of crude drug, adding 4 times the amount of water for dilution, cooling, standing at below 10°C for 12 hours, filtering, using talcum powder as the filter aid, passing through ADS-17 resin column at a flow rate of 1BV / h, first washing with 2 times the amount of purified water at a flow rate of 1BV / h, and then eluting with 2 times the amount of 70% ethanol at a flow rate of 1BV / h, collecting the eluate when the effective component flows out, recovering ethanol until there is no alcohol taste, and obtaining ginkgo crude extract. The crude extract of ginkgo is dissolved with 20 times the amount of 60% ethanol, allowed to stand at below 10°C for 12 hours, filtered until clear, ethanol is added to make the alcohol content reach 10%, passed through an ADS-F8 resin column at a flow rate of 0.7BV / h, first rinsed with 1BV of 10% ethanol at a flow rate of 0.7BV / h, the effluent and the rinse liquid are collected, and the ethanol is recovered until there is no alcohol taste to obtain total ginkgo lactones; then eluted with 3 times the amount of 70% ethanol at a flow rate of 0.7BV / h, the eluate is collected, and the ethanol is recovered until there is no alcohol taste to obtain total ginkgo flavonoids; the total ginkgo lactones and the total ginkgo flavonoids are combined to obtain the ginkgo leaf extract.

[0065] Test Example 1

[0066] The total flavonol glycosides and terpenoid lactones in the preparations were determined by high performance liquid chromatography (general rule 0512) in accordance with the provisions of the Chinese Pharmacopoeia 2020 edition under the Ginkgo Leaf Extract; the ginkgolic acid (ppm) in the Ginkgo Leaf Extract was determined by the Chinese Pharmacopoeia 2020 edition (general rule 2302). The specific results are shown in Table 1.

[0067] Table 1: Yield of Ginkgo biloba extract and determination results of total flavonoids, terpenoid lactones and ginkgolic acid in Ginkgo biloba extract

[0068]

[0069]

[0070] Comparison of Comparative Example 1 with Example 1 shows that: in the present invention, the composite enzyme composed of cellulase and β-glucosidase with the same composition ratio is superior to the composite enzyme composed of pectinase and β-glucosidase in terms of both the yield of ginkgo leaf extract and the content of total flavonol glycosides and terpenoid lactones in the ginkgo leaf extract.

[0071] Comparing Comparative Examples 2 and 3 with Example 1, it can be seen that the complex enzyme composed of cellulase and β-glucosidase has a synergistic effect on both the yield of the ginkgo leaf extract and the content of total flavonoids and total lactones in the ginkgo leaf extract.

[0072] In addition, the type of extractant and the concentration of buffer have a significant effect on the yield of ginkgo leaf extract and the content of total flavonol glycosides and terpenoid lactones in the ginkgo leaf extract. All indicators of the embodiments of the present invention are better than those of the comparative examples.

[0073] Test Example 2: Evaluation of blood lipid lowering efficacy

[0074] The ginkgo leaf extracts of Example 1-2 and Comparative Example 1-6 were dissolved in distilled water to prepare suspensions for use. Positive control drug Xuezhikang capsules (produced by Beijing Beida Weixin Biotechnology Co., Ltd.); TC, TG, HDL-C, LDL-C kits were purchased from Nanjing Jiancheng Bioengineering Research Institute Co., Ltd.; high-fat feed (formula: 78.8% basic feed, 1% cholesterol, 10% egg yolk powder, 10% lard, 0.2% bile salts).

[0075] 110 healthy male rats were selected, numbered and adaptively raised in a normal environment for 2 weeks, with free access to food and water. After the adaptive feeding, they were randomly divided into 11 groups, 10 in each group, namely blank control group, high-fat model group, positive control group, Example 1-2 group, and Comparative Example 1-6 group. Except for the blank control group, the remaining groups all used high-fat feed. The positive control group was gavaged with Xuezhikang capsule suspension (0.2g / kg), Example 1-2 group and Comparative Example 1-6 group were gavaged with Ginkgo biloba extract suspension (50mg / kg), and the blank control group and high-fat model group were gavaged with the same volume of distilled water. The gavage volume was 10mL / kg, once / d, for 30 consecutive days. Blood was collected from the abdominal aorta of the rats 24h after the last administration, and the levels of serum TC, TG, HDL-C and LDL-C were determined. SPSS13.0 software was used for one-way analysis of variance between the groups, and the difference was statistically significant (P<0.05). The results are shown in Table 2.

[0076] Table 2: Effects on serum TC, TG, HDL-C and LDL-C levels in rats

[0077]

[0078]

[0079] Note: Compared with the blank control group, # P<0.01; compared with the high-fat model group, *P<0.05, **P<0.01; compared with Example 1, the differences between the drug groups were & P<0.05.

[0080] As can be seen from the results in the above table, the TC, TG, and LDL-C levels in the blood of the rats in the high-fat model group were significantly increased compared with the blank control group, and the HDL-C content was significantly decreased compared with the blank control group, indicating that feeding a high-fat diet can cause hyperlipidemia. After administration, the TC, TG, and LDL-C levels in the blood of the rats in each administration group were significantly decreased compared with the model group, and the HDL-C content was significantly increased compared with the model group, indicating that the positive control drug, Examples 1-2, and Comparative Examples 1-6 all had a positive regulatory effect on the blood lipids of hyperlipidemia rats, but the positive regulatory effect of the embodiments was significantly better than that of the comparative examples, and was equivalent to that of the positive drug. It shows that the ginkgo leaf extract of the present invention can reduce the blood lipids of hyperlipidemia rats, indicating that it has an improvement effect on lipoprotein metabolism and "blood thickening" caused by excessive cholesterol intake, and has a significant effect on preventing hyperlipidemia, and its effect is equivalent to that of the positive control drug, and is better than the effect of other comparative examples; at the same time, the dosage of the ginkgo leaf extract of the present invention is less than that of the positive control drug.

[0081] Test Example 3: Hypoglycemic Efficacy Evaluation Test

[0082] Experimental animals: SD rats, half male and half female, weighing 180-200g. Randomly divided into 11 groups, 10 rats in each group, half male and half female, including blank group, model group, Example 1-2 group, Comparative Example 1-6 group, Xiaoke Pill group (positive drug group). Except for the blank group, the rats in the other groups were fasted but not watered for 12-16h, and STZ solution (freshly prepared) was prepared with 0.1mol / L, pH4.2 sodium citrate buffer (refrigerated), and injected intraperitoneally once. Blood sugar was tested on the 7th day of modeling. The random blood sugar value was greater than 11.1mmol / L for successful modeling, and the model animal was obtained.

[0083] Drug administration: The normal group and the model group were given distilled water, and the Example 1-2 group and the Comparative Example 1-6 group were given

[0084] The positive control group was given Xiaoke Pills by gavage at 5 pills / kg (5 pills weighing 1.25g), the Example 1-2 group and the Comparative Example 1-6 group were given Ginkgo biloba extract suspension (0.5g / kg) by gavage, and the blank group and the model group were given the same volume of distilled water by gavage. The gavage volume was 10mL / kg, once / d, and the administration was continued for 2 weeks. After the last administration, blood was collected from the tail vein after fasting for 12h, and fasting blood glucose was measured with a blood glucose meter. The results are shown in Table 3.

[0085] Table 3: Effects on blood glucose in rats

[0086] Group Blood glucose (mmoL / L, X±S) Blank Group 4.94±0.51 Model Group <![CDATA[24.33±0.62 # ]]> Positive drug group 14.14±1.21** Example 1 14.34±1.19** Example 2 14.59±1.53** Comparative Example 1 <![CDATA[18.44±1.55* & ]]> Comparative Example 2 <![CDATA[16.94±1.63* & ]]> Comparative Example 3 <![CDATA[16.77±1.36* & ]]> Comparative Example 4 <![CDATA[17.95±1.54* & ]]> Comparative Example 5 <![CDATA[18.76±1.69* & ]]> Comparative Example 6 <![CDATA[18.21±1.50* & ]]>

[0087] Note: Compared with the blank group, # P<0.01; compared with the model group, *P<0.05, **P<0.01; compared with Example 1, the differences between the drug-treated groups were & P<0.05.

[0088] As can be seen from the results in the above table, the blood glucose content in the model group rats was significantly higher than that in the blank group. After administration, the blood glucose content of the rats in each administration group decreased significantly relative to that in the model group, indicating that the positive control drug, the drugs of Examples 1-2 and Comparative Examples 1-6 can all reduce the blood glucose content of hyperglycemic rats, but the hypoglycemic effect of the embodiments is significantly better than that of the comparative examples, and is equivalent to that of the positive drugs. At the same time, the dosage of the ginkgo leaf extract of the present invention is less than that of the positive control drug.

[0089] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A ginkgo leaf extract for lowering blood sugar and lipids, It is characterized in that The ginkgo leaf extract is prepared by the following steps: (1) Extraction: Ginkgo biloba leaves are crushed and pulverized, and the crushed ginkgo leaf powder is added to an ethanol solution for extraction, and the solvent is recovered to obtain a primary ginkgo leaf extract; (2) Two-phase enzyme hydrolysis system extraction: Add complex enzyme, ethyl acetate and K to the primary extract of ginkgo leaves. 2 HPO 4 Buffer solution enzymatic hydrolysis, wherein the complex enzyme consists of cellulase and β-glucosidase; (3) recovering the solvent from the ethyl acetate phase to obtain the ginkgo leaf extract.

2. The ginkgo leaf extract according to claim 1, It is characterized in that The volume concentration of the ethanol solution in step (1) is 70-90%, and the mass volume ratio of the ginkgo leaf powder to the ethanol solution is 1:6-9.

3. The ginkgo leaf extract according to claim 1, It is characterized in that The extraction temperature in step (1) is 45-65° C., and the extraction is performed 2-3 times, each time for 1-2 hours.

4. The ginkgo leaf extract according to claim 1, It is characterized in that The composite enzyme in step (2) is composed of 1-2 parts of cellulase and 0.1-0.5 parts of β-glucosidase by weight; the amount of the composite enzyme is 1-3wt.% of the ginkgo powder.

5. The ginkgo leaf extract according to claim 1, It is characterized in that The enzymolysis temperature in step (2) is 35-40° C., the enzymolysis time is 2-3 h, and the enzymolysis pH is 4-6.

6. The ginkgo leaf extract according to claim 1, It is characterized in that K in step (2) 2 HPO 4 The volume concentration of the buffer solution is 20-30%.

7. The ginkgo leaf extract according to claim 1, It is characterized in that In step (2), the ethyl acetate and K 2 HPO 4 The volume ratio of the buffer solution is 2-3:1-2.

8. A preparation comprising the Ginkgo biloba extract according to any one of claims 1 to 7, It is characterized in that The preparation also includes pharmaceutically acceptable excipients.

9. The preparation according to claim 8, It is characterized in that The dosage form of the preparation is tablet, capsule, granule, paste, pill, oral solution, injection or suspension.

10. Use of the ginkgo leaf extract according to any one of claims 1 to 7 or the preparation according to any one of claims 8 to 9 in the preparation of a blood sugar and lipid lowering drug.

Images