CN102321138A - A kind of novel preparation method of fatty acid phytosterin ester - Google Patents

Abstract

The present invention relates to a kind of novel preparation method who utilizes the efficient synthetic fatty acid plant sterol ester of nicellar catalysis agent.The technical scheme that the present invention adopts is: earlier a certain amount of lipid acid is joined be furnished with stirring, in the reaction flask of oil bath temperature control; Feed nitrogen; Heat, add the nicellar catalysis agent of a certain amount of plant sterol and 0.5～3.0mol% again, control reaction temperature is at 80～160 ℃; Reaction 2～6h, separation and purification obtain fatty acid plant sterol ester.Present method technology is simple, and efficient is high, is convenient to scale operation.

Description

A novel preparation method of fatty acid phytosterol ester

technical field

The invention relates to a method for preparing fatty acid phytosterol esters, in particular to a solvent-free method for synthesizing fatty acid phytosterol esters with a micelle catalyst.

Background technique

Phytosterol is an active ingredient in plants, which widely exists in various vegetable oils, nuts and plant seeds, as well as plant foods and vegetables and fruits. Phytosterols have physiological effects such as reducing blood cholesterol levels, preventing prostate diseases, anti-inflammatory, anti-cancer and anti-oxidation. Phytosterols have been widely added to various foods as functional food additives. In September 2000, the U.S. Food and Drug Administration (FDA) approved that foods with added phytosterols and phytosterol esters can use the label "good for health". At present, countries such as the European Union, the United States and Japan have widely used it in foods such as butter, dairy products, chocolate, bread and margarine.

Because most phytosterols exist in the form of crystals, there are the following problems in application: the crystalline form makes their solubility and bioavailability in the human body relatively poor; they are insoluble in water and have little solubility in oil , which greatly limits its application in food. The fatty acid phytosterol esters produced by the esterification reaction of phytosterols and fatty acids can greatly improve the fat solubility of phytosterols, thereby solving the problem of inconvenient application in the food industry.

The synthesis of fatty acid phytosterol esters mainly includes enzyme-catalyzed synthesis and chemical synthesis. Most enzyme-catalyzed synthesis methods use lipase as a catalyst, but this method cannot achieve large-scale industrial production due to its high cost. The traditional chemical method mainly uses catalysts such as inorganic acid, p-toluenesulfonic acid, strong acid ion exchange resin, pyridine, sodium ethoxide and magnesium oxide, which require high reaction temperature, long time, low yield, high corrosiveness and serious environmental pollution. .

For example, CN101200754 describes a method for catalyzing the production of phytosterol esters using immobilized whole-cell enzymes in a solvent-free system. The reaction conditions of this method are relatively mild, and no organic solvents need to be added. The existing problem is that the catalytic efficiency of the enzyme is low, and the dosage is large, and the required reaction time is 48 hours to achieve an esterification rate of 60%. Simultaneously, this method is also not suitable for large-scale production.

CN1982326 discloses a preparation method of polyunsaturated fatty acid phytosterol ester. The catalysts used in this method are common acidic catalysts (such as p-toluenesulfonic acid, concentrated sulfuric acid, sodium bicarbonate) and basic catalysts (diethylamine, triethylamine, sodium methylate, sodium ethylate). Although this method does not use toxic and harmful organic solvents, it is suitable for food industry production, but the steps are cumbersome and require harsh conditions such as high temperature and vacuum.

CN1458918A discloses sterols, stanols, 4-methyl sterols and their hydrogenated homologues, triterpene alcohols and their hydrogenated homologues, and mixtures of these substances with fatty substances (capric acid, lauric acid, myristic acid, palmitic acid Acids and their mixtures) undergo esterification reactions to generate corresponding esters. The catalyst used in the method is a lanthanide oxide, the reaction time is long, and the color of the product is dark.

US6413571 discloses that conjugated linoleic acid, its methyl ester, and phytostanols can be converted into conjugated linoleic acid stanols through esterification or transesterification. The catalysts used in the esterification reaction are sulfonic acid and tin chloride, and the catalysts used in the transesterification reaction are sodium methylate and sodium hydroxide. The catalyst used is highly corrosive, and the reaction needs to be carried out under reduced pressure.

CN1245810 discloses a method of using sodium bisulfite as a catalyst to catalyze the synthesis of sterol esters from unsaturated fatty acids and phytosterols. The method has mild reaction conditions, and no inorganic acid and organic solvent are added in the reaction process. The disadvantage of this method is that the conversion rate is not high, the amount of catalyst is large, and the conversion rate above 95% needs 18 hours.

WO0061694 discloses a method for preparing polyunsaturated acid phytosterol esters. The preparation process requires dichloromethane to dissolve phytosterols and fatty acids, so this method is not suitable for the food industry.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the above-mentioned defects in the prior art, and to provide a preparation method for efficiently synthesizing fatty acid phytosterol esters in a solvent-free system using dodecylsulfate transition metal salt as a catalyst. The method has simple process, low cost, high-efficiency, concise and green synthesis route, and is convenient for large-scale production.

The present invention adopts following technical scheme:

Add a certain amount of fatty acid into a reaction flask equipped with stirring and oil bath temperature control, pass nitrogen gas, heat, then add a certain amount of phytosterol and 0.5-3.0mol% micellar catalyst, and control the reaction temperature at 80°C ~160°C, monitor the reaction process in real time, react for 2~6 hours, separate and purify to obtain fatty acid phytosterol esters.

The preparation method of the fatty acid phytosterol ester is characterized in that the phytosterol is one of stigmasterol, β-sitosterol, campesterol and brassicasterol or more than one mixed phytosterol in any proportion.

The preparation method of the fatty acid phytosterol ester is characterized in that the fatty acid is caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, linoleic acid, oleic acid, stearic acid, arachidic acid, Arachidic, erucic or behenic acid.

The preparation method of the fatty acid phytosterol ester is characterized in that the micelle catalyst is dodecyl sulfate transition metal salt, such as lauryl copper sulfate, lauryl zinc sulfate, lauryl iron sulfate , silver lauryl sulfate or cerium lauryl sulfate.

The preparation method of the fatty acid phytosterol ester is characterized in that the preparation method of the micelle catalyst lauryl sulfate transition metal salt is: 0.15mol/L sodium lauryl sulfate solution and 0.16mol/L transition metal The chloride solution is mixed at 70°C with a volume ratio of 2:1, stirred vigorously for 0.5 hours, cooled to 0°C, and precipitated dodecyl sulfate is formed, filtered, washed 3 times with water, and recrystallized.

The preparation method of the fatty acid phytosterol ester is characterized in that the molar ratio of the fatty acid to phytosterol is preferably 1:1-2:1.

The preparation method of the fatty acid phytosterol ester is characterized in that the reaction temperature is preferably 90-120°C.

The preparation method of the fatty acid phytosterol ester is characterized in that the dosage of the micelle catalyst is preferably 0.5-2.0 mol%.

The preparation method of the fatty acid phytosterol ester is characterized in that the reaction time is preferably 3-5 hours.

The preparation method of described fatty acid phytosterol ester is characterized in that described separation and purification utilizes the solubility difference of phytosterol ester and phytosterol in alkane to realize, and its step is: add normal heptane or normal hexane ( Ratio of solid to liquid (1:1, w/v), dissolve at 70°C, centrifuge at 7000 rpm for 10 min, produce a precipitate, take the supernatant, add 1mol/L NaHCO ₃ solution, shake for 10 min, then centrifuge at 7000 rpm for 10 min, take the upper layer solution, The solvent was removed by rotary evaporation to give the phytosterol ester.

The real-time reaction process monitoring method described in the present invention is thin-layer chromatography.

Among the present invention, the degree of esterification is measured by high-performance liquid chromatography, and its HPLC analysis condition: SymmetryC18 post (4.6 * 250mm, 5 μ m), column temperature: 30 ℃, mobile phase: n-hexane/isopropanol=1: 1, flow rate: 0.7mL/min, isokinetic elution, injection volume: 15μL; ELSD conditions for evaporative light scattering detector: carrier gas is N ₂ , flow rate: 1.7L/min, drift tube temperature: 60°C, working pressure: 20psi.

Compared with the prior art, the present invention has the beneficial effects as follows: (1) the high-efficiency catalyst lauryl sulfate is adopted, the required time is greatly shortened, the efficiency is improved, energy consumption is reduced, and the esterification efficiency is high, easy to operate and The product has the characteristics of easy purification and the like; (2) the process is simple, the requirements for reaction conditions are low, and industrial production is easy to realize; (3) no toxic and harmful organic solvents are used, and it is suitable for food industry production.

Detailed ways

The present invention will be described in more detail below in conjunction with specific examples. The specific parameters in the examples are only used to illustrate the present invention and not to limit the scope, and those skilled in the art can appropriately modify the parameters of the present invention.

Example 1

Weigh 17.4g of hexanoic acid and add it into a reaction flask equipped with stirring and oil bath for temperature control, blow in nitrogen, heat, and then add 50g of phytosterol and 1.0mol% copper dodecyl sulfate. The reaction temperature was controlled at 80° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was performed for 3 h. Separation and purification to obtain phytosterol hexanoate.

Example 2

Weigh 19.5g of octanoic acid and add it into a reaction flask equipped with stirring and temperature control in an oil bath, feed nitrogen, heat, and then add 50g of phytosterol and 1.2mol% zinc lauryl sulfate. The reaction temperature was controlled at 90° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was performed for 3 h. Separation and purification to obtain octanoic acid phytosterol ester.

Example 3

Weigh 30g of lauric acid and add it into a reaction flask equipped with stirring and oil bath temperature control, feed nitrogen, heat, then add 50g phytosterol and 1.5mol% copper dodecyl sulfate. The reaction temperature was controlled at 100° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was carried out for 4 h. Separation and purification to obtain phytosterol laurate.

Example 4

Weigh 42.6g of stearic acid and add it into a reaction flask equipped with stirring and oil bath temperature control, feed nitrogen, heat, then add 50g phytosterol and 2.0mol% copper dodecyl sulfate. The reaction temperature was controlled at 115° C., and the reaction progress was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was carried out for 5 h. Separation and purification to obtain phytosterol stearate.

Example 5

Weigh 51g of behenic acid and add it into a reaction flask equipped with stirring and oil bath temperature control, feed nitrogen, heat, and then add 50g of phytosterol and 2.5mol% ferric lauryl sulfate. The reaction temperature was controlled at 120° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was carried out for 6 h. Separation and purification to obtain phytosteryl behenate.

Example 6

Weigh 42g of linoleic acid and add it into a reaction flask equipped with stirring and oil bath for temperature control, blow in nitrogen, heat, and then add 50g of phytosterol and 2.0mol% zinc lauryl sulfate. The reaction temperature was controlled at 100° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was carried out for 4 h. Separation and purification to obtain linoleic acid phytosterol ester.

Example 7

Weigh 46.5g of arachidonic acid and add it into a reaction flask equipped with stirring and oil bath temperature control, blow nitrogen into it, heat, and then add 50g of phytosterol and 2.0mol% silver lauryl sulfate. The reaction temperature was controlled at 105° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was performed for 4 h. Separation and purification to obtain arachidonic acid phytosterol ester.

Example 8

Weigh 50.7g of erucic acid and add it into a reaction flask equipped with stirring and oil bath temperature control, blow nitrogen into it, heat, and then add 50g of phytosterol and 2.0mol% cerium lauryl sulfate. The reaction temperature was controlled at 110° C., and the reaction process was monitored in real time by thin-layer chromatography. Samples were taken every 0.5 h, and the reaction was carried out for 5 h. Separation and purification to obtain erucic acid phytosterol ester.

Claims (8)

1. a kind of preparation method utilizing micelle catalyst to synthesize fatty acid phytosterol ester is characterized in that described method is: a certain amount of fatty acid is joined in the reaction flask that is equipped with stirring, oil bath temperature control, feeds nitrogen, Heating, then adding a certain amount of phytosterol and 0.5-3.0mol% micellar catalyst, controlling the reaction temperature at 80-160°C, monitoring the reaction process in real time, reacting for 2-8 hours, separating and purifying to obtain fatty acid phytosterol ester. 2. the preparation method of fatty acid phytosterol ester as claimed in claim 1 is characterized in that described phytosterol is one or more arbitrary ratios in stigmasterol, β-sitosterol, campesterol and brassicasterol Blend of phytosterols. 3. the preparation method of fatty acid phytosterol ester as claimed in claim 1 is characterized in that described fatty acid is hexanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, linoleic acid, oleic acid, stearic acid Acid, Arachidic, Arachidic, Erucic, or Behenic. 4. the preparation method of fatty acid phytosterol ester as claimed in claim 1 is characterized in that described micelle catalyst is lauryl sulfate transition metal salt, as lauryl copper sulfate, lauryl zinc sulfate, Iron dodecyl sulfate, silver dodecyl sulfate or cerium dodecyl sulfate, the catalyst dosage is 0.5-3.0 mol%. 5. the preparation method of fatty acid phytosterol ester as claimed in claim 1 is characterized in that the preparation method of described micelle catalyst lauryl sulfate transition metal salt is: with 0.15mol/L sodium lauryl sulfate solution and 0.16mol/L transition metal chloride solution in a volume ratio of 2:1, mixed at 70°C, stirred vigorously for 0.5 hours, cooled to 0°C, formed dodecyl sulfate precipitate, filtered, washed 3 times with water, re- made by crystallization. 6. the preparation method of fatty acid phytosterol ester as claimed in claim 1 is characterized in that the molar ratio of described fatty acid and phytosterol is 1: 1～5: 1. 7. the preparation method of fatty acid phytosterol ester as claimed in claim 1 is characterized in that the reaction temperature is 80～160 ℃ and carries out esterification reaction 2～6h. 8. as the preparation method of the described fatty acid phytosterol ester of claim 1～7, it is characterized in that described separation and purification utilizes phytosterol ester and the solubility difference of phytosterol in alkane to realize, and its step is: to phytosterol ester mixture Add n-heptane or n-hexane (material-to-liquid ratio 1:1, w/v), dissolve at 70°C, centrifuge at 7000 rpm for 10 min, produce a precipitate, take the supernatant, add 1mol/L NaHCO ₃ solution, shake for 10 min, and then 7000 rpm Centrifuge for 10 min, take the upper layer solution, and remove the solvent by rotary evaporation to obtain phytosterol ester.