CN107417759B

CN107417759B - Preparation method for extracting phytosterol and sterol ester from paper pulp oil slick asphalt

Info

Publication number: CN107417759B
Application number: CN201710684864.3A
Authority: CN
Inventors: 孙立; 齐宝忠; 贾洪涛; 赵永强; 姜鸿奇; 鞠向慧
Original assignee: Inner Mongolia Changhui Biotechnology Co ltd
Current assignee: Inner Mongolia Changhui Biotechnology Co ltd
Priority date: 2017-08-11
Filing date: 2017-08-11
Publication date: 2020-04-17
Anticipated expiration: 2037-08-11
Also published as: CN107417759A

Abstract

The invention relates to a preparation method for extracting phytosterol and sterol ester from paper pulp oil slick, which comprises the steps of firstly, obtaining black liquor in a paper making process, separating insoluble substances, evaporating, concentrating, filtering, extracting, and then extracting the upper layer of a liquid level to obtain a black soap layer; secondly, preparing H3PO4 solution, adding the black liquid soap prepared in the first step under the stirring action, and introducing hot air into H3PO4 solution all the time in the reaction process; washing the obtained useful substance with hot water, and precipitating to obtain crude plant oil; obtaining floating oil asphalt through reduced pressure distillation; thirdly, purifying the floating oil asphalt; fourthly, adding 3-methyl-1, 3-butanediol, 1, 4-butanediol, potassium hydroxide, calcium hydroxide and lithium hydroxide into the product obtained in the third step, and removing redundant solvent after reaction; fifthly, adding the product obtained in the fourth step into trimethylpentane and dioxane, separating, and then adding the obtained product into pyridine for crystallization to obtain the phytosterol. Then obtaining the phytosterol ester under the enzyme catalysis.

Description

Preparation method for extracting phytosterol and sterol ester from paper pulp oil slick asphalt

Technical Field

The invention relates to a preparation method of vegetable fat, in particular to a preparation method of phytosterol ester.

Background

Phytosterols are a class of natural compounds with biological activity, widely found in the roots, stems, leaves and seeds of plants, are one of the components that make up cell membranes in plants, and are also precursors for the biosynthesis of various hormones and steroids. Phytosterols have been widely used in the fields of medicine, cosmetics, food (including aviation food), feed, and the like. A large number of animal experiments and human clinical test data show that the phytosterol and the phytosterol ester have significant significance for reducing the content of cholesterol in blood and relieving the occurrence of cardiovascular diseases, and are important medical raw materials and health food ingredients.

The phytosterol ester is a derivative of phytosterol, has the physiological activity function which is the same as or even better than that of the phytosterol, has lower melting point and better oil solubility, has the absorption utilization rate in organisms which is 5 times that of the phytosterol, can solve the limitation problem of the phytosterol in food application, is mainly applied to products such as fat film sauce, mayonnaise, salad dressing, cooking oil, cheese cream, salad dressing and the like, has very advanced development prospect, can improve the dietary structure of people, creates healthier diet, can effectively stop the occurrence of chronic diseases, and is beneficial to human health.

The product Benecol containing phytosterol was marketed by the company Rasio in 1995, which was the earliest international country to launch phytosterol cholesterol-lowering functional foods, and the products of countries in australia, belgium, brazil, denmark, france, germany, japan, the netherlands, spain, switzerland, sweden, the uk, the usa were listed in succession. Phytosterol food began to enter the U.S. market in 1999, and health announcements issued by the U.S. FDA: "phytosterols and esters achieve significant cholesterol lowering effects by lowering blood cholesterol levels". FDA permits food coating applications to incorporate 20% saturated phytosterols. In Japan 1999, phytosterols and esters are approved, and as functional additives for specific health food foshu for regulating blood lipid, food such as margarine, mayonnaise, sauce and the like with a lot of phytosterols added thereto are available on the market. Recently, the packed rice added with the phytosterol is introduced by the Zongteng food company, the compatibility of the phytosterol is good, the adhesion of the rice can be prevented, and the taste is improved. In 9 months of 2000, the united states Food and Drug Administration (FDA) approved the use of "good health" labels for foods with phytosterols and stanol esters added, and the department of health food of the camigy corporation introduced a phytosterol product extracted from natural sources during the international food additive package in the shanghai in 2006, 3 months, indicating that it can be added to beverages, juices, yogurt, etc., and allowing the FDA's claims of "helping to reduce the risk of coronary heart disease" to be applied to food packaging. Phytostanols with the functions of reducing cholesterol and promoting heart health are introduced in Beijing on 20.8.8.20.8.A functional food additive and an ingredient which is added into butter, cream cheese, yoghourt, milk, beverage, flour products, candy, biscuits, chocolate and other foods is convenient to process, does not affect the mouthfeel of the foods, has high safety and no side effect, obtains the safety qualification (GRAS) of the FDA in the United states, is evaluated and approved by the food authorities of European Union, and is actively applied to relevant departments in China.

Since the last 60 years of the century, research on the extraction of phytosterols from tall oil pitch scum soaps has been conducted in the european and american countries.

Early studies focused primarily on extractive separations, the hexane extraction process by Johansson et al for removing sterols from crude sulfate soap scum, Oy Kaukas for separating phytosterols from soaps using solvent mixtures containing hexane, acetone, methanol and water, Kutney et al for separating phytosterols from soaps using solvent mixtures containing water, ketones, hydrocarbons, julalan et al provide a process for producing sterols from vegetable oil pitch by extraction in water-alcohol-hydrocarbon mixtures followed by saponification and purification.

A patent in the united states reports a process for separating phytosterols from vegetable oil pitch. The method comprises neutralizing free fatty acid and resin acid in tall oil pitch with sodium hydroxide aqueous solution to obtain pitch oil containing sterol ester as main ingredient, hydrolyzing pitch oil with isopropanol solution of potassium hydroxide, adding large amount of water into saponification solution after hydrolysis, cooling thoroughly, and filtering to obtain sterol. The former soviet union patent reports a process for separating phytosterols from tall oil or vegetable oil pitch. The method adopts the normal propyl alcohol solution of sodium hydroxide for saponification, and adds aluminum oxide as a catalyst to improve the hydrolysis degree of sterol ester so as to improve the recovery rate of sterol.

U.S. patents report a process for separating sterols from tall oil or vegetable oil pitch. The method comprises dissolving asphalt with petroleum ether, sequentially adding methanol and water to make free fatty acid and resin acid in the asphalt enter methanol, and making sterol ester enter petroleum ether phase. After petroleum ether is distilled off, the sterol ester is hydrolyzed in autoclave by using methanol solution of sodium hydroxide at about 148 ℃, after hydrolysis, water and methanol are added for dilution, the sterol slurry is obtained by centrifugation, and the sterol is obtained by extracting the slurry by methyl ethyl ketone. The above methods all have the disadvantages of large solvent consumption, low sterol recovery rate, high production cost and the like. The american chemical abstracts also reported methods for separating phytosterols from tall oil pitch. The method comprises the steps of saponifying an acetone solution of sodium hydroxide, cooling the acetone solution after saponification, filtering to remove acetone insoluble fatty acid and sodium salt of resin acid, fully concentrating an acetone mother solution, cooling and filtering to obtain the phytosterol. Although the method has small solvent consumption, the sterol recovery rate is low and is only 35-40% of the theoretical amount.

Disclosure of Invention

The invention relates to a method for extracting phytosterol from plants, which comprises the following steps:

firstly, obtaining black liquor from plants such as wood in a papermaking process, separating insoluble substances, evaporating and concentrating the black liquor, filtering, extracting, and then extracting a black soap layer on the upper layer of a liquid level;

preparing H3PO4 solution, continuously adding the black liquor soap prepared in the step one under the stirring action, and introducing hot air into the H3PO4 solution all the time in the reaction process; introducing the obtained useful substance into a washing tank, washing with water in the presence of hot air, and precipitating in a precipitation tank to obtain crude vegetable floating oil; distilling the crude plant oil slick under reduced pressure to obtain oil slick asphalt,

thirdly, purifying the oil slick asphalt: dissolving the oil slick pitch in petroleum ether and isooctane in a volume ratio of 1:1, filtering to remove insoluble substances, and separating from the filtered solution to obtain solvent-free oil slick pitch;

fourthly, adding 3-methyl-1, 3-butanediol and 1, 4-butanediol into the product obtained in the third step, and adding potassium hydroxide, calcium hydroxide and lithium hydroxide in a molar ratio of 1:07:0.3, and removing redundant 3-methyl-1, 3-butanediol/1, 4-butanediol after reaction; wherein the molar ratio of the 3-methyl-1, 3-butanediol to the 1, 4-butanediol is 2.5-3.5: 1;

fifthly, adding the product obtained in the fourth step into a mixed system of trimethylpentane and dioxane, separating the solution, and adding the product into pyridine for crystallization to obtain the phytosterol.

The invention also relates to a method for preparing sterol ester from plants, which comprises the step of reacting the sterol prepared by the method with pseudomonas fluorescens/rhizopus arrhizus lipase and citric acid/malic acid at the temperature of between 8 and 15Mpa and between 20 and 30 ℃ for 2 to 3 hours, wherein the molar ratio of the sterol to the citric acid/malic acid is 1:1 to 1:5, and the content of the pseudomonas fluorescens/rhizopus arrhizus lipase is 4500-5000U/g.

Wherein the molar ratio of the citric acid to the malic acid is 1-3: 1.

Wherein the molar ratio of the 3-methyl-1, 3-butanediol to the 1, 4-butanediol is 2.5-3.5: 1.

Preferably, the ratio of Pseudomonas fluorescens/Rhizopus arrhizus lipase is 1-2: 1.

Preferably, the pressure is 12.8 MPa.

Preferably, the temperature is 24.8 ℃.

The preferred reaction time is 2.3 h.

Preferably, the molar ratio of sterol to citric acid/malic acid is 1: 2.5.

Preferably, the ratio of Pseudomonas fluorescens/Rhizopus arrhizus lipase is 1.5: 1.

The invention needs to be particularly illustrated as follows:

1. in the preparation process of crude vegetable floating oil, sulfuric acid is always and always used in the prior art for treatment, and the applicant researches and discovers that acidification by sulfuric acid brings at least the following adverse factors, wherein the process of diluting sulfuric acid to obtain a proper concentration is always accompanied by danger, smell is choked, and is also accompanied by a large amount of heating phenomena, even more, production safety problems are generated, sulfuric acid and a byproduct mirabilite are always corroded by pipelines to cause unnecessary leakage, although the prior art is always accompanied by the problems, technical personnel always do not overcome the problems from the technical source, but always adopt a closed reaction zone, increase investment and exhaust facilities, improve the labor protection of workers, introduce labor cost and cause the final product price, and the problems can not be completely solved, to avoid this problem, the applicant has surprisingly discovered, through studies on this acidification process, that phosphoric acid is better able to avoid the above-mentioned problem, even though the prior art occasionally mentions that other acids can be used, as an equivalent to sulfuric acid, but the advantages of using phosphoric acid are not at all realized, nor are the advantages of using phosphoric acid realized.

2. The selection of the solvent for purifying the tall oil pitch is very important, and the prior art does not research the selection, but only widely adopts low-carbon saturated alkanes such as dichloromethane, trichloromethane, hexane, heptane, octane, decane, cyclohexane and the like and substituted alkanes, and the applicant surprisingly finds that petroleum ether and isooctane have good effect on purifying insoluble substances, the purification effect of the petroleum ether and the isooctane reaches 90 percent, the effect on effectively separating insoluble substances in the tall oil pitch is not expected in advance, and the mixing ratio of the petroleum ether and the isooctane is optimal when the volume ratio of the petroleum ether to the isooctane is 1: 1.

3. The alkaline substance and the proportion thereof selected in the third step obtain ideal effects, the molar ratio of potassium hydroxide to calcium hydroxide to lithium hydroxide is 1:07:0.3, sodium hydroxide is always adopted in the prior art, and a general thinking and thinking trend is formed by the technicians in the field, although the technical bias is not necessarily met, but at least with little thought of the effect of the general class of bases on the reactants, the skilled person will always be unaware of the direct use of sodium hydroxide, and occasionally potassium hydroxide, because the properties of the two are closer, but the use of calcium hydroxide is less, and even the use of lithium hydroxide is not conceivable, the inventor considers that for the fine chemical engineering, the influence of various factors should be studied with great care, researches show that compared with the single base catalysis system in the prior art, the preparation of the three substances in a specific ratio can well obtain the catalysis effect.

4. The third step is another key step of the present invention, and therefore, in addition to the above-mentioned specific catalytic proportioning system, another important point is the choice of alcohol reagent, which is widely used in the prior art and is methanol, ethanol, propanol, even isopropanol, because these raw materials are simple and easily available, but for the extraction preparation of sterol, the yield, purity, etc. are not compared or improved, such as the influence of hydrolysis conversion rate, the inventors have surprisingly found that the use of the alcohol of C4-5, especially 3-methyl-1, 3-butanediol in combination with 1, 4-butanediol can effectively promote the hydrolysis process and improve the purity, preferably the molar ratio of the two is 2.5-3.5: 1.

5. It is also important to emphasize that, in the latter solvent dissolution, the solvent, although it may be possible to choose a solvent system similar to that of the previous one, the prior art is rarely concerned with this step, even if it is a choice of solvents of the same kind, but the present inventors always believe that the choice of solvent system, here should be differentiated from the solvent system of the second step, although it is possible to achieve similar functions, but it is evident that the effect of the different systems on the solubility of the fine components, the applicant has surprisingly found that a mixed solvent system of trimethylpentane and dioxane has a very good effect on the removal of the non-polar materials thereof, thus facilitating and improving the purity and yield of sterols, the optimum ratio being the mass ratio, 1-5:1, preferably 1.5: 1.

6. In a further aspect of the present invention, pyridine is used as a recrystallization solvent, more crystallization solvents are alcohols such as methanol and the like, and acetone is occasionally used in the prior art, but the present inventors have unexpectedly found that pyridine as a crystallization solvent can be used for well recrystallizing sterol, thereby obtaining the purity and yield of the desired target product, in consideration of the solubility and separation characteristics of the solvents.

7. For the preparation of sterol ester, the esterification reaction in the prior art is most commonly the direct esterification of carboxylic acid, the catalyst usually adopts organic acid or inorganic acid and salt thereof, and also adopts anhydride esterification, and an alcohol ester exchange method is also commonly adopted, which usually adopts sodium methoxide and other similar catalysts. The method for synthesizing the phytosterol ester by enzyme catalysis has the advantages of mild reaction conditions, easy separation and purification of products and the like, and opens up a new way for the production of the phytosterol ester. When the applicant screens enzymes, the inventor surprisingly finds that the pseudomonas fluorescens/rhizopus arrhizus lipase can effectively promote the esterification reaction, particularly when the content of the pseudomonas fluorescens/rhizopus arrhizus lipase is 4500-.

Detailed Description

The preparation is carried out according to the procedures of the invention contents, and the specific formula contents are as follows: and (3) mixing 100g of the floating asphalt obtained in the second step.

TABLE 1 materials usage ratios of examples and comparative examples

TABLE 2 raw material ratios and process conditions for sterol ester preparation

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. A method for extracting phytosterol from wood is characterized by comprising the following steps:

firstly, obtaining black liquor from wood in a papermaking process, separating insoluble substances, evaporating and concentrating the black liquor, filtering, extracting, and then extracting a black soap layer on the upper layer of a liquid level;

II, preparation H₃PO₄Adding the solution into the black liquor soap prepared in the step one under the stirring action, and introducing hot air into H all the time in the reaction process₃PO₄In liquid; introducing the obtained useful substance into a water washing tank for air hot water washing, and then performing precipitation in a precipitation tank to obtain crude plant floating oil; carrying out reduced pressure distillation on the obtained crude plant oil slick to obtain oil slick asphalt;

thirdly, purifying the oil slick asphalt: dissolving the oil slick asphalt in petroleum ether and isooctane, filtering to remove insoluble substances, and separating from the filtered solution to obtain solvent-free oil slick asphalt;

fourthly, adding 3-methyl-1, 3-butanediol, 1, 4-butanediol and 1:0.7:0.3 of potassium hydroxide, calcium hydroxide and lithium hydroxide into the product obtained in the third step, and removing redundant 3-methyl-1, 3-butanediol and 1, 4-butanediol after reaction;

fifthly, adding the product obtained in the fourth step into trimethylpentane and dioxane, separating the solution, and adding the product into pyridine for crystallization to obtain the phytosterol.

2. A method for preparing sterol ester from wood is characterized in that sterol prepared by the method in claim 1 reacts with pseudomonas fluorescens/rhizopus arrhizus lipase and citric acid/malic acid at 8-15Mpa and 20-30 ℃ for 2-3h, wherein the molar ratio of sterol to citric acid/malic acid is 1:1-1:5, and the content of pseudomonas fluorescens/rhizopus arrhizus lipase is 4500-5000U/g.

3. The method of claim 2, wherein the molar ratio of citric acid to malic acid is 1-3: 1.

4. The process of claim 1, wherein the molar ratio of 3-methyl-1, 3-butanediol to 1, 4-butanediol is from 2.5 to 3.5: 1.

5. The method of claim 2, wherein the ratio of pseudomonas fluorescens/rhizopus arrhizus lipase is 1-2: 1.

6. The method of claim 2, wherein the pressure is 12.8 Mpa.

7. The method of claim 2, at a temperature of 24.8 ℃.

8. The process according to claim 2, the reaction time being 2.3 h.

9. The method of claim 2, wherein the molar ratio of sterol to citric acid/malic acid is 1: 2.5.

10. The method of claim 2, wherein the ratio of pseudomonas fluorescens/rhizopus arrhizus lipase is 1.5: 1.