Comprehensive separation process for multiple active components in peanut coat

Abstract

The invention relates to the field of separation and extraction of active ingredients of natural products, in particular to a comprehensive separation process of various active ingredients in peanut coats. Through reasonable matching of all the steps, various peanut coat active ingredients including peanut coat total sterol, peanut coat saturated fatty acid, peanut coat unsaturated fatty acid, peanut coat total flavonoid compounds and peanut coat procyanidine can be obtained with high yield through a set of process, the yield is high, and the method is a method capable of effectively and comprehensively utilizing peanut coat resources and improving the production efficiency. And the method is suitable for industrial technological processes.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of natural product active ingredient separation and extraction, and particularly relates to a comprehensive separation process of multiple active ingredients in peanut skin. BACKGROUND

[0002] Peanut skin is the seed coat of Arachis hypogaea L. in the genus Arachis of the family Leguminosae, i.e. the purple-red thin skin on the outside of peanut. Peanut skin contains rich active ingredients and has the effects of stopping bleeding, dispersing blood stasis and reducing swelling, and is widely used in clinic. The best method for eating is to boil. According to traditional Chinese medicine, peanut skin can tonify the Qi of the spleen and stomach, and achieve the effect of nourishing blood and stopping bleeding. According to western medicine, peanut skin can inhibit the dissolution of fibrin, increase the content of platelets, improve the quality of platelets, improve the defects of coagulation factors, strengthen the contraction function of capillaries, and promote the hematopoietic function of bone marrow. Modern scientific research has found that peanut skin is rich in many natural active ingredients that are beneficial to health. Peanut skin contains high-grade fatty acids, especially unsaturated fatty acids, which have the functions of reducing blood lipids and serum cholesterol, can reduce the risk of coronary heart disease, prevent platelet aggregation and thrombosis. Peanut skin is rich in proanthocyanidins, which have strong antioxidant and free radical elimination effects, can effectively eliminate superoxide anion free radicals and hydroxyl free radicals, and can also improve blood circulation, protect vision, eliminate edema, moisturize the skin, protect the cardiovascular and cerebrovascular system, and have anti-inflammatory and anti-allergic effects. The flavonoids in peanut skin have antioxidant and anti-inflammatory effects, can scavenge free radicals, delay aging and enhance capillary toughness, help reduce the tendency to bleed, and can also promote platelet production and shorten the clotting time, and have auxiliary improvement effects on anemia and purpura. In addition, peanut skin is also rich in plant sterols, which have physiological functions such as regulating blood lipids and antioxidant effects. However, in production and life, people often ignore the nutritional and health care value of peanut skin. In daily consumption or processing of peanuts, peanut skin is often removed and discarded, which is an important manifestation. The existing process technology for utilizing peanut skin is usually directed to a certain active ingredient, and multiple active ingredients in peanut skin cannot be obtained at the same time, peanut skin resources are not comprehensively utilized, which causes great waste and environmental pollution. For example:

[0003] CN101665482A discloses a peanut skin proanthocyanidin purification method, which is prepared from defatted peanut skin through steps of ethanol microwave extraction, concentration, vacuum freeze-drying, dissolution, HPD-826 macroporous adsorption resin adsorption, ethanol elution, concentration and drying to obtain peanut skin proanthocyanidin refined product.

[0004] CN103194089A discloses a method for extracting peanut skin red pigment by microwave-assisted extraction, which is prepared from peanut skin through steps of ethanol water soaking, microwave extraction, secondary extraction with anhydrous ethanol, membrane filtration, concentration, freeze-drying to obtain peanut skin red pigment product.

[0005] CN103877144A discloses the application of peanut skin active components and compositions containing the peanut skin active components, which is prepared by using peanut skin as raw material, extracting with a mixed solution of ethanol and water, adsorbing with HP-20 resin, washing with water, eluting with ethanol, concentrating, and drying to obtain peanut skin active components (anthocyanins).

[0006] CN108285458A discloses a method for extracting procyanidin A2 from peanut skin, which is prepared by using peanut skin as raw material, extracting with hot water, adsorbing with macroporous resin, eluting, and fine separating by medium-low pressure preparation chromatography to obtain procyanidin A2.

[0007] CN111454242A previously applied by the inventor discloses a method for separating multiple active components from peanut skin, which is prepared by using peanut skin as raw material, extracting with lipophilic organic solvent, separating with silica gel column, extracting with hot water, nanofiltration, separating with polyamide resin, and separating with alumina chromatography to obtain senior fatty acid, catechin, resveratrol, and procyanidin in sequence. The method can effectively separate multiple active components of peanut skin, but there is still room for improvement. SUMMARY

[0008] In order to overcome the insufficient utilization of peanut skin active components in the prior art and to improve and enhance the space, the present application provides a comprehensive separation process for multiple active components in peanut skin. Through reasonable collocation of each step, multiple active components of peanut skin including peanut skin total sterols, peanut skin saturated fatty acids, peanut skin unsaturated fatty acids, peanut skin total flavonoid compounds, and peanut skin procyanidins can be obtained with high yield through one process, and the yield is high. It is a process flow that can effectively and comprehensively utilize peanut skin resources and is suitable for industrialization. The present application realizes the above-mentioned purposes through the following technical solutions:

[0009] A comprehensive separation process for multiple active components in peanut skin includes the following steps:

[0010] (1) The peanut skin raw material is crushed, low-polarity organic solvent is added for reflux extraction twice, and solid-liquid separation is performed to obtain an extract and an extraction residue;

[0011] (2) The extract is passed through a silica gel chromatography column, and the silica gel chromatography column effluent is collected; after column loading, the silica gel chromatography column is first flushed with organic solvent A, the silica gel column effluent and the flushing liquid are combined to obtain combined liquid A for use; the silica gel chromatography column is eluted with eluent A, eluent A is collected, concentrated, and dried to obtain peanut skin total sterols; the eluent A is a mixed solution of low-polarity organic solvent and ethyl acetate;

[0012] (3) The combined liquid A obtained in step (2) is passed through a silver nitrate-silica gel column, and after the column is filled, the silver nitrate-silica gel column effluent and the washing liquid are combined, and the organic solvent is evaporated to obtain peanut skin saturated fatty acids; the silver nitrate-silica gel column is eluted with eluent B, and the eluent B is collected and the organic solvent is evaporated to obtain peanut skin unsaturated fatty acids; the eluent B is a mixed solution of a low-polarity organic solvent and at least one of ether, acetone, and ethyl acetate;

[0013] (4) The extraction residue of step (1) is first dried by evaporating the organic solvent, and then extracted with acid water twice;

[0014] (5) After the acid water extraction liquid is filtered, it is passed through a non-polar macroporous adsorption resin column, and the column effluent is collected for later use; after adsorption is completed, the resin column is desorbed with an ethanol aqueous solution, the desorption liquid is concentrated to be alcohol-free, dried, and peanut skin total flavonoid compounds are obtained;

[0015] (6) Polar macroporous adsorption resin separation: the column effluent of step (5) is passed through a polar macroporous adsorption resin column, and after adsorption is completed, the resin column is desorbed with an ethanol aqueous solution, the desorption liquid is concentrated to be alcohol-free, and dried to obtain peanut skin proanthocyanidins.

[0016] Preferably, in step (1), the low-polarity organic solvent includes but is not limited to petroleum ether, n-pentane, isopentane, cyclopentane, n-hexane, cyclohexane, 6# solvent oil, 120# solvent oil, and the amount of low-polarity organic solvent used in the two extractions is 8-10 times, 5-8 times (L / kg) of the weight of the peanut skin raw material, respectively, and the reflux extraction time is 2-3 hours, 1-2 hours, respectively. The purpose of using low-polarity organic solvent to extract twice is to fully leach the components with small polarity such as fatty acids and sterols in peanut skin according to the principle of "like dissolves like".

[0017] Preferably, in step (2), the amount of silica gel used for column chromatography is 0.1-0.3 times (L / kg) of the weight of the peanut skin raw material, the height-diameter ratio of the silica gel chromatography column is 5-8:1, and the flow rate of the column is 0.5-2.0 BV / hour. The purpose of passing the low-polarity organic solvent extract through the silica gel chromatography column is first to decolorize and remove impurities, and to retain the impurities such as pigments in the silica gel column, thereby obtaining peanut skin high-grade fatty acids with light color and high purity; secondly, to retain the sterols that can be adsorbed by silica gel in the silica gel column for subsequent elution and separation.

[0018] Preferably, in step (2), the volume ratio of ethyl acetate in the eluent A is 5-10%, the low-polarity organic solvent includes but is not limited to petroleum ether, n-pentane, isopentane, cyclopentane, n-hexane, cyclohexane, 6# solvent oil, 120# solvent oil, the amount of the eluent A is 1-4 BV, and the flow rate of the elution is 0.5-2.0 BV / hour. The purpose of using the eluent A to elute the silica gel column is to elute the sterols adsorbed by the silica gel from the silica gel column. If the amount of the eluent A or the proportion of ethyl acetate is too small, the above purpose cannot be fully achieved, resulting in a low yield of sterols. If the amount of the eluent A or the proportion of ethyl acetate is too large, although the sterols can be completely eluted, excessive elution also occurs, and pigments and other impurities are also eluted, resulting in a low content of sterols.

[0019] Preferably, in step (3), the amount of the silver nitrate-silica gel is 0.1-0.5 times (L / kg) the weight of the peanut skin raw material, the height-diameter ratio of the silver nitrate-silica gel column is 5-8:1, and the flow rate of the column is 0.5-2.0 BV / hour. The purpose of passing the silica gel column effluent and the washing liquid of step (2) through the silver nitrate-silica gel column is to separate the unsaturated fatty acids from the saturated fatty acids by using the principle that the silver nitrate-silica gel column can adsorb the unsaturated fatty acids but not the saturated fatty acids.

[0020] Preferably, in step (3), the volume ratio of ethyl ether, acetone, and ethyl acetate in the eluent B is 5-10%, the low-polarity organic solvent includes but is not limited to petroleum ether, n-pentane, isopentane, cyclopentane, n-hexane, cyclohexane, 6# solvent oil, 120# solvent oil, the amount of the eluent B is 1-4 BV, and the flow rate of the elution is 0.5-2.0 BV / hour. The purpose of using the eluent B to elute the silver nitrate-silica gel column is to elute the unsaturated fatty acids adsorbed by the silver nitrate-silica gel from the silver nitrate-silica gel column.

[0021] Preferably, in step (4), the acid water is one or more of hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, and citric acid with a mass percentage concentration of 0.05%-1% (preferably 0.1-0.5%, more preferably 0.1-0.2%); the extraction temperature is 50-70°C, and the amount of the acid water used for the two extractions is 8-10 times and 5-8 times (L / kg) the weight of the peanut skin raw material, respectively, and the extraction time is 2-3 hours and 1-2 hours, respectively. The purpose of the acid water extraction is to fully leach the flavonoids and proanthocyanidins in the peanut skin organic solvent extraction residue. The inventors have found that, compared with hot water extraction at a natural pH value, the use of acid water for heating extraction is beneficial to improve the yield of flavonoids and proanthocyanidins in peanut skin, which may be because the acidic environment can reduce the thermal degradation of the above components.

[0022] Preferably, in step (5), the type of non-polar macroporous adsorption resin includes, but is not limited to, D101, D101C, LX-100B, LX-T28, and LX-T81. The amount of non-polar macroporous adsorption resin used is 0.1 to 0.3 times (L / kg) of the weight of the peanut skin raw material. The height-to-diameter ratio of the non-polar macroporous adsorption resin column is 3 to 8:1, and the flow rate on the column is 0.5 to 2.0 BV / hour.

[0023] Preferably, in step (6), the polar macroporous adsorption resin is of the type including but not limited to LSA-10, LX-12, XDA-6, and LX-32, the amount of polar macroporous adsorption resin is 0.1 to 0.3 times (L / kg) of the weight of the peanut skin raw material, the height-to-diameter ratio of the polar macroporous adsorption resin column is 3 to 8:1, and the flow rate on the column is 0.5 to 2.0 BV / hour.

[0024] Preferably, in steps (5) and (6), the volume fraction of ethanol in the ethanol-water solution used for desorption is 60-80%, the amount of ethanol used is 1.5-3.0 BV, and the flow rate of desorption is 0.5-2.0 BV / hour.

[0025] In this invention, the order in which the acidic aqueous extract is loaded onto the two types of macroporous adsorption resin columns cannot be reversed. This is because the non-polar macroporous adsorption resin selectively adsorbs flavonoids from the acidic aqueous extract, but it does not adsorb proanthocyanidins (or the adsorption amount is very small). The polar macroporous adsorption resin, on the other hand, not only adsorbs a large amount of proanthocyanidins but also has a significant adsorption effect on flavonoids. Therefore, to maximize the separation of peanut skin flavonoids and proanthocyanidins, the method of this invention employs the sequence of first passing the extract through the non-polar macroporous adsorption resin column and then through the polar macroporous adsorption resin column to ensure the yield of both proanthocyanidins and flavonoids.

[0026] In the method of this invention, 1 BV = 1 column volume.

[0027] The principle of this invention is as follows: Peanut skin raw material is first extracted with a low-polarity organic solvent, which fully leaches out components with low polarity such as fatty acids and sterols. Through adsorption and elution using a silica gel column, peanut skin sterol compounds can be obtained; however, higher fatty acids from peanut skin are not adsorbed by the silica gel column. The column effluent containing higher fatty acids from peanut skin is then further adsorbed and eluted using a silver nitrate-silica gel column, separating saturated and unsaturated fatty acids from peanut skin. The residue from the organic solvent extraction of peanut skin can be extracted again with acidic water to leach out flavonoids and proanthocyanidins. By employing a continuous process of first passing through a non-polar macroporous adsorption resin column and then through a polar macroporous adsorption resin column, the separation of flavonoids and proanthocyanidins from peanut skin is achieved.

[0028] The beneficial effects of the method of the present invention are as follows:

[0029] (1) The peanut skin obtained by the method of the present invention has a saturated fatty acid content of 93.05% and a yield of 95.16%; the peanut skin obtained by the method of the present invention has an unsaturated fatty acid content of 94.77% and a yield of 92.23%; the peanut skin obtained by the method of the present invention has a total sterol content of 83.87% and a yield of 90.07%; the peanut skin obtained by the method of the present invention has a total flavonoid content of 82.74% and a yield of 84.95%; the peanut skin obtained by the method of the present invention has a proanthocyanidin content of 97.04% and a yield of 90.59%.

[0030] (2) The method of the present invention provides an improved method for continuously extracting multiple active ingredients from peanut skins, which can make comprehensive use of peanut skin resources. The process is continuous, simple, highly operable, low in production cost, safe and environmentally friendly, and the active ingredients are diverse, high in content and high in yield, making it suitable for industrial production. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0032] The present invention will be further described below with reference to the embodiments.

[0033] The peanut skin used in this embodiment of the invention contains 8.36 wt% unsaturated fatty acids, 1.956 wt% saturated fatty acids, 5.606 wt% proanthocyanidins, 1.096 wt% total sterols, and 0.536 wt% total flavonoids. The macroporous adsorption resin used in this embodiment of the invention was purchased from Xi'an Lanxiao New Material Technology Co., Ltd. The silica gel (200 mesh) used in this embodiment of the invention was purchased from Qingdao Haiyang Chemical Co., Ltd. Unless otherwise specified, all excipients or chemical reagents used in this embodiment of the invention were obtained through conventional commercial channels.

[0034] In this embodiment of the invention, gas chromatography-mass spectrometry (GC-MS) was used to detect the content of saturated fatty acids and unsaturated fatty acids in peanut skin, and ultraviolet spectrophotometry was used to determine the content of proanthocyanidins, total sterols, and total flavonoids in peanut skin.

[0035] Figure 1 This is a schematic diagram of the method flow of the present invention.

[0036] Example 1

[0037] (1) Organic solvent extraction: Take 1 kg of peanut skin raw material, crush it to 20 mesh, add petroleum ether, heat and reflux twice (10 L for 2 hours the first time; 7 L for 1 hour the second time), filter, and obtain petroleum ether extract. Peanut skin petroleum ether extract residue is reserved for later use.

[0038] (2) Separation by silica gel column: The petroleum ether extract was passed through a silica gel column at a flow rate of 1 BV / h (the amount of silica gel used in the column was 0.25 L, and the height-to-diameter ratio of the silica gel column was 6:1), and the effluent from the silica gel column was collected. After the column was loaded, the silica gel column was washed with 2 BV of petroleum ether, and the effluent from the silica gel column and the washing solution were combined and set aside. The silica gel column was eluted with 2 BV of eluent A (petroleum ether: ethyl acetate = 95:5, volume ratio) at a flow rate of 1 BV / h, and the eluent A was collected, concentrated, and dried to obtain 11.62 g of total sterols from peanut skin.

[0039] (3) Separation by silver nitrate-silica gel column: The effluent and washing solution from step (2) of the silica gel chromatography column were passed through a silver nitrate-silica gel column at a flow rate of 1 BV / hour (the amount of silver nitrate-silica gel was 0.25 L, and the height-to-diameter ratio of the silver nitrate-silica gel column was 6:1). After the column was loaded, the silver nitrate-silica gel column was washed with 2 BV of petroleum ether. The effluent and washing solution were combined and concentrated to remove all organic solvents, yielding 19.91 g of saturated fatty acids from peanut skin. The silver nitrate-silica gel column was then eluted with 3 BV of eluent B (petroleum ether: diethyl ether = 94:6, volume ratio) at a flow rate of 1.5 BV / hour. The eluent B was collected and concentrated to remove all organic solvents, yielding 81.06 g of unsaturated fatty acids from peanut skin.

[0040] (4) Acid water extraction: Take the peanut skin organic solvent extraction residue from step (1), first evaporate the organic solvent completely, and then extract it twice with a 0.2% hydrochloric acid aqueous solution (10L for the first time and 2 hours for the second time; 7L for the second time and 1 hour for the second time). The extraction temperature is 60℃ to obtain acid water extract.

[0041] (5) Separation with non-polar macroporous adsorption resin: After filtering the acidic water extract, it was passed through a D101 resin column at a flow rate of 2 BV / h (the amount of macroporous adsorption resin used was 0.3 L, and the height-to-diameter ratio of the macroporous adsorption resin column was 5:1). The effluent from the column was collected for later use. After adsorption, the resin column was desorbed with 2 BV of ethanol (ethanol volume fraction was 75%, and the desorption flow rate was 1.0 BV / h). The desorbed solution was concentrated until no alcohol was found, and then dried to obtain 5.58 g of total flavonoid compounds from peanut skin.

[0042] (6) Polar macroporous adsorption resin separation: Take the effluent from step (5) and pass it through an LSA-10 resin column at a flow rate of 2 BV / hour (the amount of macroporous adsorption resin is 0.3 L, and the height-to-diameter ratio of the macroporous adsorption resin column is 5:1). After adsorption, the resin column is desorbed with 2.5 BV ethanol (ethanol volume fraction is 70%, desorption flow rate is 1.2 BV / hour). The desorbed solution is concentrated until there is no alcohol, dried, and 51.92 g of peanut husk proanthocyanidins are obtained.

[0043] The content of saturated fatty acids in peanut skin obtained in this example was 93.05%, and the yield of saturated fatty acids was 95.01%, as determined by gas chromatography-mass spectrometry (GC-MS). The content of unsaturated fatty acids in peanut skin obtained in this example was 94.77%, and the yield of unsaturated fatty acids was 91.89%. The content of total sterols in peanut skin obtained in this example was 83.87%, and the yield of total sterols was 89.41%, as determined by ultraviolet spectrophotometry. The content of total flavonoids in peanut skin obtained in this example was 80.69%, and the yield of total flavonoids was 84.95%. The content of proanthocyanidins in peanut skin obtained in this example was 97.04%, and the yield of proanthocyanidins was 89.97%.

[0044] Example 2

[0045] (1) Organic solvent extraction: Take 1 kg of peanut skin raw material, crush it to 20 mesh, add 6# solvent oil, heat and reflux to extract twice (the first time 9L, extraction time 3 hours; the second time 6L, extraction time 1.5 hours), filter to obtain 6# solvent oil extract, and keep the peanut skin 6# solvent oil extract residue for later use.

[0046] (2) Silica gel column separation: The extract of No. 6 solvent oil was passed through a silica gel chromatography column at a flow rate of 1.2 BV / h (the amount of silica gel used in the column was 0.2 L, and the height-to-diameter ratio of the silica gel column was 5:1), and the effluent of the silica gel column was collected. After the column was loaded, the silica gel column was rinsed with 2 BV of No. 6 solvent oil, and the silica gel column effluent and rinsing solution were combined and set aside. The silica gel column was eluted with 3 BV of eluent A (No. 6 solvent oil: ethyl acetate = 96:4, volume ratio) at a flow rate of 1.5 BV / h, and the eluent A was collected, concentrated, and dried to obtain 11.96 g of total sterols from peanut skin.

[0047] (3) Separation by silver nitrate-silica gel column: The effluent and washing solution from step (2) of the silica gel chromatography column were passed through a silver nitrate-silica gel column at a flow rate of 1.5 BV / hour (the amount of silver nitrate-silica gel was 0.2 L, and the height-to-diameter ratio of the silver nitrate-silica gel column was 5:1). After the column was loaded, the silver nitrate-silica gel column was first washed with 2 BV of 6# solvent oil. The effluent and washing solution were combined and concentrated to remove all organic solvents, yielding 20.25 g of saturated fatty acids from peanut skin. The silver nitrate-silica gel column was then eluted with 2 BV of eluent B (6# solvent oil: acetone = 97:3, volume ratio) at a flow rate of 1 BV / hour. The eluent B was collected and concentrated to remove all organic solvents, yielding 82.35 g of unsaturated fatty acids from peanut skin.

[0048] (4) Acid water extraction: Take the peanut skin organic solvent extraction residue from step (1), first evaporate the organic solvent completely, and then extract it twice with a 0.1% sulfuric acid aqueous solution (9L for the first time and 3 hours for the second time; 6L for the second time and 1.5 hours for the second time). The extraction temperature is 65℃ to obtain acid water extract.

[0049] (5) Separation with nonpolar macroporous adsorption resin: After filtering the acidic water extract, it was passed through an LX-T28 resin column at a flow rate of 1.5 BV / hour (the amount of macroporous adsorption resin used was 0.2 L, and the height-to-diameter ratio of the macroporous adsorption resin column was 6:1). The effluent from the column was collected for later use. After adsorption, the resin column was desorbed with 2.5 BV ethanol (ethanol volume fraction was 70%, and the desorption flow rate was 1.2 BV / hour). The desorbed solution was concentrated until no alcohol was found, and then dried to obtain 5.43 g of total flavonoid compounds from peanut skin.

[0050] (6) Polar macroporous adsorption resin separation: Take the effluent from step (5) and pass it through an XDA-6 resin column at a flow rate of 1.5 BV / hour (the amount of macroporous adsorption resin is 0.2 L, and the height-to-diameter ratio of the macroporous adsorption resin column is 6:1). After adsorption, the resin column is desorbed with 2 BV of ethanol (ethanol volume fraction is 75%, desorption flow rate is 1.0 BV / hour). The desorbed solution is concentrated until there is no alcohol, dried, and 52.34 g of peanut husk proanthocyanidins are obtained.

[0051] Gas chromatography-mass spectrometry (GC-MS) analysis showed that the peanut skin obtained in this example contained 91.64% saturated fatty acids, with a yield of 95.16%; the peanut skin contained 93.63% unsaturated fatty acids, with a yield of 92.23%; ultraviolet spectrophotometry analysis showed that the peanut skin contained 82.09% total sterols, with a yield of 90.07%; the peanut skin contained 82.74% total flavonoids, with a yield of 84.77%; and the peanut skin contained 96.93% proanthocyanidins, with a yield of 90.59%.

[0052] Comparative Example

[0053] Steps (1) to (4) are the same as in the embodiment;

[0054] (5) Polar macroporous adsorption resin separation: After filtering the acidic water extract from step (4), pass it through an LSA-10 resin column at a flow rate of 2 BV / hour (the amount of macroporous adsorption resin used is 0.3 L, and the height-to-diameter ratio of the macroporous adsorption resin column is 5:1). After adsorption, the resin column is desorbed with 2.5 BV ethanol (ethanol volume fraction is 70%, desorption flow rate is 1.2 BV / hour). The desorbed solution is concentrated until there is no alcohol, dried, and 56.75 g of peanut husk proanthocyanidins are obtained.

[0055] (6) Separation with non-polar macroporous adsorption resin: The effluent from step (5) was passed through a D101 resin column at a flow rate of 2 BV / hour (the amount of macroporous adsorption resin was 0.3 L, and the height-to-diameter ratio of the macroporous adsorption resin column was 5:1). The effluent was collected for later use. After adsorption, the resin column was desorbed with 2 BV of ethanol (ethanol volume fraction was 75%, and the desorption flow rate was 1.0 BV / hour). The desorbed solution was concentrated until no alcohol was found, and then dried to obtain 2.32 g of total flavonoid compounds from peanut skin.

[0056] The total flavonoid content of peanut skin obtained in this example was 40.64%, and the yield of total flavonoids of peanut skin was 17.59%, as determined by gas chromatography-mass spectrometry (GC-MS). The content of proanthocyanidins of peanut skin obtained in this example was 85.22%, and the yield of proanthocyanidins of peanut skin was 86.27%.

Claims

1. A process for the integrated isolation of a plurality of active ingredients from peanut hulls, characterized in that, The method comprises the following steps: (1) crushing peanut hull raw material, adding low-polarity organic solvent for reflux extraction twice, and separating solid and liquid to obtain extract and extraction residue; (2) passing the extract through a silica gel chromatographic column, collecting silica gel chromatographic column effluent; after column loading, first washing the silica gel chromatographic column with organic solvent A, combining silica gel column effluent and washing liquid to obtain combined liquid A for use; eluting the silica gel chromatographic column with eluent A, collecting eluent A, concentrating, and drying to obtain peanut hull total sterols; the eluent A is a mixed solution of low-polarity organic solvent and ethyl acetate; (3) passing the combined liquid A obtained in step (2) through a silver nitrate-silica gel column, after column loading, first washing the silver nitrate-silica gel column with organic solvent B, combining silver nitrate-silica gel column effluent and washing liquid, and evaporating organic solvent to obtain peanut hull saturated fatty acids; eluting the silver nitrate-silica gel column with eluent B, collecting eluent B, and evaporating organic solvent to obtain peanut hull unsaturated fatty acids; the eluent B is a mixed solution of low-polarity organic solvent and at least one of diethyl ether, acetone, and ethyl acetate; (4) taking the extraction residue of step (1), first evaporating organic solvent completely, and then extracting with acid water twice; (5) filtering the acid water extract, passing it through a non-polar macroporous adsorption resin column, collecting column effluent for use; after adsorption, desorbing the resin column with an ethanol aqueous solution, concentrating the desorption liquid to be alcohol-free, and drying to obtain peanut hull total flavonoid compounds; (6) polar macroporous adsorption resin separation: passing the column effluent of step (5) through a polar macroporous adsorption resin column, after adsorption, desorbing the resin column with an ethanol aqueous solution, concentrating the desorption liquid to be alcohol-free, and drying to obtain peanut hull procyanidins.

2. The integrated separation process of claim 1, wherein, In step (1), the low-polarity organic solvent includes but is not limited to petroleum ether, n-pentane, isopentane, cyclopentane, n-hexane, cyclohexane, 6# solvent oil, and 120# solvent oil; the amount of low-polarity organic solvent used in the two extractions is 8-10 times and 5-8 times (L / kg) of the weight of peanut hull raw material, respectively; and the reflux extraction time is 2-3 hours and 1-2 hours, respectively.

3. The integrated separation process of claim 1, wherein, In step (2), the amount of column chromatography silica gel is 0.1-0.3 times (L / kg) of the weight of peanut hull raw material; the height-diameter ratio of the silica gel chromatographic column is 5-8:1; and the column loading flow rate is 0.5-2.0 BV / hour.

4. The integrated separation process of claim 1, wherein, In step (2), in the eluent A, the volume fraction of ethyl acetate is 5-10%; the low-polarity organic solvent includes but is not limited to petroleum ether, n-pentane, isopentane, cyclopentane, n-hexane, cyclohexane, 6# solvent oil, and 120# solvent oil; the amount of eluent A is 1-4 BV; and the elution flow rate is 0.5-2.0 BV / hour.

5. The integrated separation process of claim 1, wherein, In step (3), the amount of silver nitrate-silica gel is 0.1-0.5 times (L / kg) of the weight of peanut hull raw material; the height-diameter ratio of the silver nitrate-silica gel column is 5-8:1; and the column loading flow rate is 0.5-2.0 BV / hour.

6. The integrated separation process of claim 1, wherein, In step (3), the volume ratio of the eluent B consisting of the group of ethyl ether, acetone, ethyl acetate is 5-10%, the low-polarity organic solvent includes but is not limited to petroleum ether, n-pentane, isopentane, cyclopentane, n-hexane, cyclohexane, 6# solvent oil, 120# solvent oil, the amount of the eluent B is 1-4 BV, and the flow rate of the elution is 0.5-2.0 BV / hour.

7. The integrated separation process of claim 1, wherein, In step (4), the acid water is one or more of hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, and citric acid with a mass percentage concentration of 0.05%-1%, the extraction temperature is 50-70℃, the amount of the acid water used for twice extraction is 8-10 times and 5-8 times (L / kg) of the weight of the peanut skin raw material, respectively, and the extraction time is 2-3 hours and 1-2 hours, respectively.

8. The integrated separation process of claim 1, wherein, In step (5), the type of the non-polar macroporous adsorption resin includes but is not limited to D101, D101C, LX-100B, LX-T28, and LX-T81, the amount of the non-polar macroporous adsorption resin is 0.1-0.3 times (L / kg) of the weight of the peanut skin raw material, the height-diameter ratio of the non-polar macroporous adsorption resin column is 3-8:1, and the flow rate of the column is 0.5-2.0 BV / hour.

9. The integrated separation process of claim 1, wherein, In step (6), the type of the polar macroporous adsorption resin includes but is not limited to LSA-10, LX-12, XDA-6, and LX-32, the amount of the polar macroporous adsorption resin is 0.1-0.3 times (L / kg) of the weight of the peanut skin raw material, the height-diameter ratio of the polar macroporous adsorption resin column is 3-8:1, and the flow rate of the column is 0.5-2.0 BV / hour.

10. The integrated separation process of claim 1, wherein, In steps (5) and (6), the volume fraction of ethanol in the ethanol aqueous solution used for desorption is 60-80%, the amount of ethanol is 1.5-3.0 BV, and the flow rate of the desorption is 0.5-2.0 BV / hour.

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