阅读说明：本技术 一种芦荟多糖的提取方法 (Extraction method of aloe polysaccharide ) 是由 周石洋 陈本寿 于 2021-09-01 设计创作，主要内容包括：本发明属于植物提取技术领域,具体涉及一种芦荟多糖的提取方法,包括预处理步骤,预处理步骤之后还依次包括冷冻、浸泡、浓缩、脱蛋白、透析、醇沉、离心和干燥步骤,所述冷冻是指于-10～-5℃条件下处理10-12h。本发明显著提高了芦荟多糖的收率和总糖含量。(The invention belongs to the technical field of plant extraction, and particularly relates to an extraction method of aloe polysaccharide, which comprises a pretreatment step, wherein the pretreatment step is sequentially followed by freezing, soaking, concentrating, deproteinizing, dialyzing, alcohol precipitating, centrifuging and drying steps, and the freezing is carried out for 10-12h at the temperature of-10 to-5 ℃. The invention obviously improves the yield and the total sugar content of the aloe polysaccharide.)

1. The extraction method of the aloe polysaccharide comprises a pretreatment step and is characterized in that the pretreatment step sequentially comprises the steps of freezing, soaking, concentrating, deproteinizing, dialyzing, alcohol precipitating, centrifuging and drying, wherein the freezing refers to the treatment for 10-12 hours at the temperature of-10 to-5 ℃.

2. The extraction method according to claim 1, wherein the soaking is performed in water at room temperature for 10-60 min.

3. The extraction method according to claim 1, wherein the concentration is performed at a temperature of-0.08 MPa to-0.1 MPa and 50-55 ℃.

4. The extraction process according to claim 1 or 2, characterized in that the deproteinization step comprises: adding chloroform and n-butanol, magnetically stirring for 10-60min, and centrifuging.

5. The extraction process according to claim 4, wherein the volume ratio of chloroform to n-butanol is from 2:1 to 5: 1.

6. The extraction method of any one of claims 1 to 5, wherein the alcohol precipitation comprises: carrying out alcohol precipitation treatment by absolute ethyl alcohol, centrifuging the mixture after alcohol precipitation and collecting precipitates.

7. The extraction process according to any one of claims 1 to 6, wherein the drying is carried out at 50 ℃ to 60 ℃ for 20 to 24 hours.

8. The extraction process according to any one of claims 1 to 7, comprising the following steps in sequence:

pretreatment: taking fresh folium Aloe, removing necrotic part, cleaning, air drying, and mashing;

freezing; treating the pretreated aloe leaves at-10 to-5 ℃ for 10 to 12 hours;

soaking: soaking frozen Aloe in water at room temperature for 10-60min, vacuum filtering at normal pressure, collecting filtrate, soaking the residue in water at room temperature for 10-60min, repeating the operation for 2 times, centrifuging the filtrate, collecting supernatant, and mixing the supernatants;

concentration: concentrating under-0.08 MPa to-0.1 MPa at 50-55 deg.c;

deproteinization: adding chloroform and n-butanol into the concentrated solution, magnetically stirring for 10-60min, centrifuging, and collecting supernatant; transferring the supernatant to a dialysis bag for dialysis treatment, wherein the cut-off molecular weight of the dialysis bag is more than 3500;

alcohol precipitation: adding absolute ethyl alcohol into the solution obtained by dialysis for alcohol precipitation for 20-24h, centrifuging the mixture obtained after alcohol precipitation and collecting precipitates;

and (3) drying: drying the precipitate obtained by alcohol precipitation at 50-60 deg.C for 20-24 h.

Technical Field

The invention belongs to the technical field of plant extraction, and particularly relates to an extraction method of aloe polysaccharide.

Background

Aloe is a perennial evergreen herbaceous plant of the genus Aloe of the family Liliaceae of the order Liliales (yearly, and heroic. Aloe polysaccharide research [ J ]. Harbin university of commerce (Nature science edition), 2003(4): 377-.

Research shows that aloe mainly comprises hydroxyanthraquinone derivatives (such as aloe-emodin, aloenin, aloesin, aloe tincture, etc.), polysaccharides (such as glucose, glycocoll, arabinose, fructose, rhamnose, etc.), amino acids (such as arginine, heaven-tomanine, glutamic acid, leucine, isoleucine, tryptophan, threonine, phenylalanine, lysine, valine, etc.), lipids (such as isoprenoids, alkanes, fatty acids, sterols, etc.), organic acids (such as succinic acid, malic acid, lactic acid, etc.), minerals (such as silicon, aluminum, calcium, magnesium, iron, manganese, cobalt, titanium, etc.), vitamins (such as VB, vitamin B, vitamin A, and other₁、VB₂、VB₆、VB₁₂VC, VA, carotene, etc.) and biological enzymes (such as lipoxygenase, superoxide dismutase, catalase, bradykinin enzyme, etc.) (yankee, Yuan, alomizedHealth-care efficacy and product development of chemical ingredients [ J]Agricultural and pastoral product development, 2001(4) 6-8; zhang Zheng Jie, Zhao Xiu Ying, shou Zhi Jian, Jiang Ju Mei, Wang Zhi Zi, Wang Zhi Yong Min, Zhang hong Li, study of Aloe chemical composition [ J]The northwest plant bulletin, 1990(2) 135-.

Wherein, the aloe polysaccharide is the main active component of aloe (Wu Guangfeng, Tang Jiang, research on purification and in vitro antioxidant activity of aloe polysaccharide [ J ]. food industry science and technology, 2002,23(7):10-12), and has pharmacological actions of immunoregulation, tumor resistance, mutation resistance, radiation resistance, aging resistance, ulcer resistance, endotoxin resistance, attenuation and synergy on tumor chemotherapy (Zhongbingan, Xiang, Gaoyong, research on aloe polysaccharide [ J ]. Harbin university of commerce (Nature science edition), 2003(04):377 381).

At present, the extraction method of aloe polysaccharide mainly comprises an enzymolysis method and a hot water extraction method. For example, patent document CN02148422.8 discloses a method for extracting aloe polysaccharide, which comprises the following steps: A. cutting fresh folium Aloe into small pieces, extracting with water at 40-80 deg.C, and filtering to obtain extractive solution; B. centrifuging the extractive solution, collecting supernatant, adding 95% ethanol into the supernatant to make ethanol content in the solution reach 50-80%, and precipitating to obtain crude Aloe polysaccharide; C. dissolving crude aloe polysaccharide in water, adding 20-50% trichloroacetic acid or trifluoroacetic acid to make the final concentration of trichloroacetic acid or trifluoroacetic acid reach 2-6%, standing, centrifuging and removing precipitate to obtain secondary supernatant; D. loading the secondary supernatant onto macroporous resin column bed, and eluting with water until effluent is colorless and transparent; E. mixing the filtrates, concentrating, adding 95% ethanol to reach ethanol content of 55-85%, precipitating to obtain polysaccharide, and freeze drying to obtain refined aloe polysaccharide. However, the extraction rate of the method is low, about 2 per mill (calculated by wet weight).

Disclosure of Invention

In view of the above, the present invention aims to provide a method for extracting aloe polysaccharides with high extraction rate.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the extraction method of the aloe polysaccharide comprises a pretreatment step, and the pretreatment step sequentially comprises the steps of freezing, soaking, concentrating, deproteinizing, dialyzing, alcohol precipitating, centrifuging and drying, wherein the freezing refers to the treatment for 10-12 hours at the temperature of-10 to-5 ℃.

Further, the soaking refers to soaking in water at room temperature for 10-60 min.

Furthermore, the amount of water used in the soaking process is 3-8 times of the mass of aloe.

Further, the concentration is carried out under the conditions of-0.08 MPa to-0.1 MPa and 50 ℃ to 55 ℃.

Further, the deproteinizing step comprises: adding chloroform and n-butanol, magnetically stirring for 10-60min, and centrifuging.

Further, the volume ratio of the chloroform to the n-butanol is 2:1-5: 1.

Further, the alcohol precipitation comprises: carrying out alcohol precipitation treatment by absolute ethyl alcohol, centrifuging the mixture after alcohol precipitation and collecting precipitates.

Further, the dosage of the absolute ethyl alcohol is 3-5 times of the volume of the liquid after dialysis treatment.

Further, the drying refers to drying treatment for 20-24h at 50-60 ℃.

Further, the extraction method of the aloe polysaccharide sequentially comprises the following steps:

pretreatment: taking fresh folium Aloe, removing necrotic part, cleaning, air drying, and mashing;

freezing; treating the pretreated aloe leaves at-10 to-5 ℃ for 10 to 12 hours;

soaking: soaking frozen Aloe in water at room temperature for 10-60min, vacuum filtering at normal pressure, collecting filtrate, soaking the residue in water at room temperature for 10-60min, repeating the operation for 2 times, centrifuging the filtrate, collecting supernatant, and mixing the supernatants;

concentration: concentrating under-0.08 MPa to-0.1 MPa at 50-55 deg.c;

deproteinization: adding chloroform and n-butanol into the concentrated solution, magnetically stirring for 10-60min, centrifuging, and collecting supernatant; transferring the supernatant to a dialysis bag for dialysis treatment, wherein the cut-off molecular weight of the dialysis bag is more than 3500;

alcohol precipitation: adding absolute ethyl alcohol into the solution obtained by dialysis for alcohol precipitation for 20-24h, centrifuging the mixture obtained after alcohol precipitation and collecting precipitates;

and (3) drying: drying the precipitate obtained by alcohol precipitation at 50-60 deg.C for 20-24 h.

The invention has the beneficial effects that:

the invention obviously improves the yield of the aloe polysaccharide.

The invention obviously improves the total sugar content of the aloe polysaccharide.

Drawings

FIG. 1 is an infrared spectrum; wherein the abscissa is the wave number in cm^-1(ii) a The ordinate is the absorption intensity in%;

fig. 2 is a nuclear magnetic resonance hydrogen spectrum in which the abscissa is the chemical shift.

FIG. 3 is a nuclear magnetic resonance carbon spectrum in which the abscissa is the chemical shift.

Detailed Description

The examples are provided for better illustration of the present invention, but the present invention is not limited to the examples. Therefore, those skilled in the art should make insubstantial modifications and adaptations to the embodiments of the present invention in light of the above teachings and remain within the scope of the invention.

In the invention, the specific method for infrared spectrum detection comprises the following steps: the chemical bonds and functional groups of the polysaccharide were analyzed using a Fourier transform infrared spectrometer (IR 408, Shimadzu, Japan); the KBr is taken as the background during the measurement and is 500cm at 4000-^-1Scanning within the range;

in the invention, the specific method for detecting the nuclear magnetic resonance comprises the following steps: with D₂And O is used as a solvent to prepare a polysaccharide solution of 50 mg/mL.¹H NMR and¹³c NMR spectrum is recorded by Bruker AV III-600NMR spectrum;

the method for detecting the yield of the aloe polysaccharide comprises the following steps: the mass ratio of the obtained refined polysaccharide to the total mass of fresh aloe is calculated.

The method for detecting the total sugar content of the aloe polysaccharide comprises the following steps: the total sugar content of aloe polysaccharide is determined by phenol-sulfuric acid method. The aloe polysaccharide is hydrolyzed into monosaccharide under the condition of concentrated sulfuric acid and dehydrated, then phenol is added, the phenol and the dehydrated monosaccharide are condensed to form a colored compound, the maximum absorption is realized at 490nm, the absorbance value is in direct proportion to the concentration of the sugar within a certain range, and the content of the monosaccharide in the treated solution can be analyzed by an absorbance spectrophotometry. Firstly, making a standard curve: accurately weighing 50mg of glucose dried to constant weight at 105 ℃ in a 500mL volumetric flask to prepare a 0.1mg/mL + standard solution, and respectively preparing 0, 0.02, 0.04, 0.06, 0.08 and 0.1mg/mL with distilled water. 1mL of the standard solution was added to 1mL of 5% phenol solution, and 5mL of concentrated sulfuric acid was added rapidly, followed by standing for 10 min. Shaking, standing at 30 deg.C for 30min, measuring OD value at 490nm, and making into standard curve with glucose content as abscissa and OD value as ordinate. Measuring the content of the sample: and (3) sucking 1.0mL of aloe polysaccharide sample liquid, measuring the OD value according to the steps, and substituting the OD value into the standard curve to calculate the total sugar content of the sample.

Example 1

The extraction method of the aloe polysaccharide comprises the following specific steps:

pretreatment: taking fresh folium Aloe, removing necrotic part, cleaning, naturally air drying, weighing 1000g folium Aloe, mashing, and freezing in-10 deg.C refrigerator for 12 hr;

freezing: soaking the frozen aloe juice in 5000g of water for 30min, vacuum-filtering at normal pressure, collecting filtrate, soaking the filter residue in 5000g of water for 30min, vacuum-filtering at normal pressure, and collecting filtrate; centrifuging the filtrate at 4000 rpm for 5min, collecting supernatant, and mixing the supernatants;

concentration: concentrating the combined liquid under 0.1MPa at 50 deg.C to 1000mL volume, and stopping concentrating to obtain crude aloe polysaccharide solution;

deproteinization: adding 100mL of chloroform and 25mL of n-butanol into the crude polysaccharide solution, carrying out vigorous magnetic stirring treatment at normal temperature for 30min, centrifuging at the rotating speed of 4000 rpm for 10min, and collecting supernatant; transferring the supernatant into dialysis bag (molecular weight cutoff is greater than 3500), and dialyzing to obtain refined aloe polysaccharide solution;

alcohol precipitation: placing the refined aloe polysaccharide solution into a 5000mL beaker, adding 4000mL of absolute ethyl alcohol, and precipitating with ethanol for 24 h; centrifuging the mixture after alcohol precipitation for 10min at the rotating speed of 4000 rpm, and collecting precipitates;

and (3) drying: and (3) drying the precipitate in a constant-temperature drying box at 50 ℃ for 24 hours to obtain the compound.

Performance detection

The aloe polysaccharide obtained in example 1 was subjected to infrared spectroscopy and nuclear magnetic resonance carbon spectroscopy, and the results are shown in FIGS. 1 to 3.

As can be seen from FIG. 1, the aloe polysaccharides obtained in example 1 were found to be 3326cm^-1A broad peak appears, which is a characteristic absorption peak of O-H stretching vibration; 2930cm^-1Is a characteristic adsorption peak of C-H stretching vibration; 1617cm^-1Is the bending vibration induced O-H adsorption peak; 1415cm^-1Characteristic absorption peaks of C-H shear vibrations; 1153cm^-1Is the O-H shear oscillation peak; 1022cm^-1Is the C-O-C stretching vibration peak.

As can be seen from FIG. 2, the aloe polysaccharides obtained in example 1 at 3.46-4.42ppm are the proton chemical shifts of aloe polysaccharides C2-C6; 5.34-5.43ppm is the chemical shift of the proton peak at C1 of aloe polysaccharides; 2.02-2.11ppm is the chemical shift of the methyl group in the aloe polysaccharide methylation.

As can be seen from FIG. 3, the aloe polysaccharide prepared in example 1 has a chemical shift of the resonance region of aloe polysaccharide C1 at 100.36 ppm; 60.72-76.22ppm is the chemical shift of resonance area of carbon at C2, C3, C4, C5, C6 and other sites on the sugar ring; 20.33ppm are-CH₃Chemically shifting the resonance region of (a).

The aloe polysaccharide of example 1 was tested for yield and total sugar content, and the results are shown in table 1.

TABLE 1 test results

Detecting content	Example 1
		Yield per mill	5.1
Total sugar content/%)	97.3

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.