CN103319561A - Method for extracting phytosterol and cane wax from sugarcane peeling - Google Patents

Abstract

The invention discloses a method for extracting phytosterols and sucrose wax from sugarcane skin, comprising: taking sugarcane skin, drying, and pulverizing to obtain powder; placing the powder in ethanol for a period of time, filtering, collecting the filtrate and Filter residue: Phytosterol is extracted from the filtrate, and cane wax is obtained from the filter residue by reflux extraction with n-hexane. The invention uses sugarcane skin as raw material, has wide sources of raw materials, has no toxic and side effects, can obtain phytosterols and sucrose wax at the same time, and has a simple production process, firstly extracts sucrose fat and refines phytosterols through a step-by-step method, and then extracts sucrose wax, effectively reducing Solvent consumption. In addition, the phytosterol and sugarcane wax extracted by the method of the present invention have high yields, which can respectively reach 2.17‰-2.88‰ and 5.16%-6.28%.

Description

A method for extracting phytosterols and cane wax from sugarcane bark

technical field

The invention relates to the field of biotechnology, in particular to a method for extracting phytosterols and cane wax from sugarcane bark.

Background technique

Phytosterols are a class of steroidal compounds in nature and belong to saturated (or unsaturated) secondary alcohols. Phytosterols are essential components for stabilizing plant cell membranes, similar to the role of cholesterol in animals, and are widely distributed in vegetable oils, seeds, nuts, vegetables and fruits. Phytosterols have many physiological functions, the most notable of which is cholesterol-lowering effect. In addition, phytosterols also play an important role in inhibiting tumors, preventing heart disease, anti-cancer, and regulating immune function, and are known as "the key to life" by the scientific community.

At present, phytosterols are mainly extracted from deodorized distillates such as soybean oil and rapeseed oil. U.S. Patent US5117015 reported that using a special solvent system to obtain concentrated stigmasterol products from deodorized distillates, the total sterol content increased from 10% to 15% (of which stigmasterol accounted for 17% to 19%) to 85% to 96% ( Among them, stigmasterol accounts for 20% to 25%).

At this stage, there are related articles and reports on the process of extracting phytosterols from the filter mud of sugarcane sugar factories at home and abroad, but there are few reports on the extraction and utilization of phytosterols directly from sugarcane bark.

Sugarcane wax is the wax on the epidermis of sugarcane. Sugarcane wax contains physiologically active substances mainly composed of long-chain (C20-C30) higher fatty alcohols. Cane wax has been proved to be one of the most ideal raw materials for obtaining octacosanol. Li Xiaoguang et al. have described a method for preparing high-purity octacosanol from sugarcane wax in the Chinese patent publication number CN1297873A. Crude cane wax is a mixture of real wax and fatty lipids, and the soft fatty substances must be removed to obtain refined cane wax similar to other vegetable waxes. Bibliographical reports extract the method of sugarcane wax mostly to extract crude sugarcane wax from filter mud with organic solvents such as benzene, toluene, sherwood oil, gasoline, trichlorethylene, dichloroethylene, carbon tetrachloride, gasoline and ethanol mixed solution, after Refining with organic solvents (acetone, isopropanol) to remove fatty substances and refining cane wax. In 1992, He Weiping and others used petroleum ether-ethanol solution to extract crude cane wax, and then refined it twice with organic solvents (acetone, isopropanol) to remove fatty substances. The refined cane wax was up to 5.8%. In 2011, Chen Qianlin et al. used mixed solvent hot reflux extraction method and ultrasonic assisted extraction method to extract with ethanol-gasoline mixed solvent with 70% ethanol content, and the yield of purified cane wax could reach 4.6%. But there are the following defects: (1) The solvents used for refining, such as acetone, are highly volatile, which is not conducive to safe production; (2) Some reagents, such as isopropanol, are expensive and unfavorable to recycle, so they are not suitable for large-scale production.

In addition, due to the different types of substances contained in the raw materials and the limitations of the extraction process, at present, the preparation of phytosterols and cane wax are all extracted through separate production processes, and the extraction cost is expensive.

Contents of the invention

The invention provides a method for extracting phytosterols and sucrose wax from sugarcane husks. The phytosterols and sucrose wax can be obtained simultaneously by using sugarcane husks as raw materials. The production process is simple, and the safety and yield are high.

A method for extracting phytosterols and cane wax from sugarcane bark, comprising:

(1) Take sugarcane skin, dry it, and crush it to make powder;

(2) Put the powder in ethanol for a period of time, filter, and collect the filtrate and filter residue;

(3) Phytosterols are extracted from the filtrate, and cane wax is obtained from the filter residue by reflux extraction with n-hexane.

Cane fat is soluble in low-temperature ethanol, but sucrose wax is insoluble. Therefore, through ethanol extraction, sucrose resin exists in the filtrate, while sucrose wax exists in the filter residue, and the separation of sucrose resin and sucrose wax is realized. Then extract phytosterols and sucrose wax from the filtrate and filter residue respectively. Ethanol is the extraction reagent, can adopt 95% ethanol or absolute ethanol, if no special instructions in the present invention, all refer to absolute ethanol.

During ethanol extraction, the liquid-to-solid ratio is 8-4:1, preferably 6-5:1, more preferably 5:1. With the increase of the liquid-to-solid ratio, the greater the concentration difference of sucrose sugar inside and outside the cell, the greater the driving force of mass transfer, which is beneficial to the leaching of sucrose sucrose, but too large a solid-to-liquid ratio not only causes waste of reagents, but also increases the evaporation of the subsequent filtrate. complexity.

Those skilled in the art can understand that the ratio of extractant to material usually refers to the volume-to-mass ratio (ml:g) of the extractant and the material.

Appropriate extraction time and temperature are conducive to the effective separation of sucrose and sucrose wax, and ensure the full separation of sucrose sucrose, and increase the yield of phytosterols and sucrose wax. Preferably, the extraction temperature is 30-35° C., and the extraction time is 4-8 hours. If the extraction temperature is too high, the sucrose wax will be easily precipitated, which will affect the separation of sucrose wax and sucrose resin; If the fat is not leached, if the leaching time is too long, the leaching amount of impurities will be increased, which will eventually affect the purity and yield of phytosterols and cane wax.

The extraction method of the phytosterol is as follows: take the filtrate, evaporate to dryness, add alkali to carry out saponification reaction, add an extractant to extract after the reaction is complete, take the oil phase, and evaporate to dryness to obtain the phytosterol.

In step (1), the temperature of the filtrate when evaporated to dryness is 40-50°C.

During saponification, the alkali is preferably an aqueous solution of potassium hydroxide or an ethanol solution of potassium hydroxide, the concentration of which is 2 to 4 mol/L, and the consumption of potassium hydroxide is 2 to 10% of the weight of sucrose.

The saponification temperature is 80-90° C., and the time is 2-4 hours. Preferably, the saponification time is 2 hours.

In order to increase the yield of phytosterols, before extraction, a metal salt precipitant is added to the reaction solution for precipitation. The metal salt precipitant is a monovalent or multivalent metal salt, preferably potassium chloride. According to the principle of similar miscibility, potassium chloride can increase the ion concentration of the water phase to increase the polarity, and phytosterols tend to precipitate from the water phase into the petroleum ether layer, and potassium chloride can quickly dissolve in the above reaction solution.

When petroleum ether is extracted, the amount of petroleum ether used each time is 1-2 times the mass of the original sugarcane skin, and the number of extractions is usually 2-3 times.

The n-hexane can extract the sucrose wax from the filter residue, and the ratio of liquid to material is 6-8:1, preferably 7-8:1 during reflux extraction.

The temperature and time of the reflux extraction affect the extraction efficiency and purity of the sucrose wax, the temperature of the reflux extraction is 70-80° C., and the time is 2-3 hours.

The sucrose wax described in the present invention has a melting point between 76-82 DEG C and is hard sucrose wax without sucrose fat.

Compared with prior art, the beneficial effect of the present invention is:

(1) The present invention uses sugarcane husk as a raw material, has a wide source of raw materials, has no toxic and side effects, and can simultaneously obtain phytosterols and cane wax.

(2) The production process of the present invention is simple. The sugarcane fat is firstly extracted and the phytosterols are refined by a step-by-step method, and then the sugarcane wax is extracted, thereby effectively reducing solvent consumption.

(3) The yield of phytosterol and cane wax extracted by the method of the present invention is high, and the yield of phytosterol can reach 2.17‰-2.88‰, which can further refine and develop high-purity sterol monomers such as β-sitosterol and stigmasterol; The wax is extracted by reflux of n-hexane, and the yield can reach 5.16%-6.28%. In addition, the sugarcane wax prepared by the present invention has the characteristics of conventional vegetable waxes in appearance, is hard cane wax without sucrose fat, and can be further refined to develop octacosanol.

(4) The solvent ethanol, n-hexane and petroleum ether used in the extraction process of the present invention are single and easy to obtain, and have high safety.

Detailed ways

The present invention will be further explained below in conjunction with specific examples.

Example 1

(1) Dry and pulverize the sugarcane skin at 30°C, weigh 5g of the powder, extract it with 25mL alcohol at 30°C for 8 hours, and filter it with suction;

(2) The resulting filtrate was evaporated to dryness at 40°C to obtain sucrose fat, and the obtained sucrose fat was hydrolyzed and saponified with 5 mL of 2mol/L potassium hydroxide ethanol solution at 80°C for 2 hours;

(3) After hydrolysis, add 1 g of potassium chloride to the saponification solution, and extract the unsaponifiable matter with 10 mL of petroleum ether for 3 times each time, and evaporate the solution to dryness to obtain phytosterols;

(4) The filter residue obtained in (1) was extracted with 35 mL of n-hexane solvent (liquid-solid ratio: 7:1) at 70°C for 3 hours under reflux, and the extract was evaporated to dryness at 70°C to obtain sugarcane wax.

Through verification experiments, the prepared sucrose fat weighed 257mg, and the yield was 5.14%.

The total sterol content of the sample was determined by Liebermann-Burchard colorimetry to be 8.98%. After saponification, 14.42 mg of phytosterols were obtained, and the yield of phytosterols was 2.88‰; sugarcane wax was 258 mg, and the yield was 5.16%.

The Liebermann-Burchard colorimetric method for determining the total sterol content of a sample is as follows: place the sucrose resin obtained in step (2) in a 10 mL brown measuring bottle, add acetic anhydride to dilute to the mark, add 1 drop of concentrated sulfuric acid, and vortex for 1 min. Let it stand for 13 minutes, then detect its absorbance value at a wavelength of 650nm, and calculate its concentration according to the standard curve.

Example 2

(1) Dry and pulverize the sugarcane skin at 30°C, weigh 5g of the powder, extract it with 25mL alcohol at 30°C for 4 hours, and filter it with suction;

(2) After the obtained filtrate was evaporated to dryness at 40°C, the obtained sucrose was hydrolyzed and saponified with 5 mL of 4mol/L potassium hydroxide ethanol solution at 90°C for 2 hours;

(3) After hydrolysis, add 1 g of potassium chloride to the saponification solution, and extract the unsaponifiable matter twice with 10 mL of petroleum ether each time, combine the extraction solutions and evaporate to dryness to obtain phytosterols;

(4) Extract the filter residue obtained in (1) with 40 mL of n-hexane solvent (liquid-solid ratio: 8:1) at 80°C for 2 hours under reflux, and evaporate the extract to dryness at 70°C to obtain sugarcane wax.

Through the verification experiment, the yield of 202 mg of sucrose fat was 4.05%, the Liebermann-Burchard colorimetric method determined the total sterol content of the sample to be 8.53%, and 12.40 mg of phytosterol was obtained after saponification, and the yield of phytosterol was 2.48‰; Sugarcane wax 314mg, the yield is 6.28%.

Example 3

(1) Dry and pulverize the sugarcane skin at 30°C, weigh 20g of the powder, extract it with 100mL alcohol at 35°C for 4 hours, and filter it with suction;

(2) The obtained filtrate was evaporated to dryness at 40°C to obtain sucrose resin, which was hydrolyzed and saponified with 5 mL of 4mol/L potassium hydroxide ethanol solution at 80°C for 2 hours;

(3) After hydrolysis, add 4 g of potassium chloride to the saponification solution, and extract the unsaponifiable matter with 20 mL of petroleum ether each time for 3 times, combine the extraction solutions and evaporate to dryness to obtain phytosterols;

(4) Extract the filter residue obtained in (1) with 140 mL of n-hexane (liquid-solid ratio: 7:1) at 75°C for 2.14 hours under reflux, and evaporate the extract to dryness at 70°C to obtain sugarcane wax.

Through the verification experiment, the yield of 774 mg of sucrose fat was 3.87%, the Liebermann-Burchard colorimetric method determined the total sterols of the sample to be 8.65%, 43.42 mg of phytosterols were obtained after saponification, and the yield of phytosterols was 2.17‰; sugarcane wax was obtained by extraction 1.123g, yield 5.62%.

Claims (10)

1. method of extracting plant sterol and cerosin from Sugarcane peel. comprises:

(1) get Sugarcane peel., drying is pulverized and is made powder;

(2) described powder is placed ethanol lixiviate for some time, filter, collect filtrate and filter residue;

(3) extraction obtains plant sterol from described filtrate, utilizes the normal hexane refluxing extraction to obtain cerosin from described filter residue.

2. the method for claim 1 is characterized in that, the lixiviate liquid ratio is 8～4: 1.

3. the method for claim 1 is characterized in that, the temperature of described lixiviate is 30～35 ℃, and the time is 4～8 hours.

4. the method for claim 1 is characterized in that, the extracting method of described plant sterol is: get described filtrate, evaporate to dryness adds alkali and carries out saponification reaction, and the rear adding extraction agent that reacts completely extracts, and gets oil phase, and evaporate to dryness obtains plant sterol.

5. method as claimed in claim 4 is characterized in that, described alkali is potassium hydroxide, and concentration is 2～4mol/L.

6. method as claimed in claim 4 is characterized in that, the temperature of described saponification reaction is 80～90 ℃, and the time is 2～4 hours.

7. method as claimed in claim 4 is characterized in that, in the step (3), before the extraction, adds metallic compound precipitator in reaction solution.

8. method as claimed in claim 4 is characterized in that, described extraction agent is sherwood oil.

9. the method for claim 1 is characterized in that, during refluxing extraction, and solid-liquid ratio 6～8: 1.

10. the method for claim 1 is characterized in that, the temperature of described refluxing extraction is 70～80 ℃, and the time is 2～3h.