CN105777599A - Method for preparing canthaxanthin through oxidation - Google Patents
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Abstract
The invention discloses a method for preparing canthaxanthin through oxidation.The method includes the steps that beta-carotene serves as the raw material, sulfur oxide urea or urea peroxide serves as an oxidizing agent, an oxidizing reaction is conducted, and the canthaxanthin is obtained.The method has the advantages that operation is simple, the reaction is stable, and the trigger condition is mild; the oxidizing agents including sulfur oxide urea and urea peroxide can be decomposed into H2O2 and elemental oxygen in solvent, O2 is released slowly, the content of active oxygen is high, stability is high, the utility of time is long, no side effect exists, no toxin or public hazard exists, and it is beneficial to achieve industrialized clean production.
Description
Technical field
The preparation method that the present invention relates to canthaxanthin, particularly relates to a kind of method that oxidizing process prepares canthaxanthin.
Background technology
Canthaxanthin, also known as canthaxanthin, chemical name: beta-carotene-4,4 '-diketone, is a Carotenoids.Canthaxanthin is darkviolet crystal or crystalline powder, fusing point about 210 DEG C (decomposition), need to be stored in the light-proofness container of filling with inert gas.It is dissolved in chloroform (10%), is slightly soluble in vegetable oil (0.005%), acetone (0.03%), water insoluble, ethanol, propylene glycol.Stable industrial products are the solution form being dissolved in oils and fats or organic solvent, or the orange of water dispersible is to red powder or particle form.
Existing canthaxanthin preparation method mainly includes synthetic method, oxidizing process and biological fermentation process etc..Wherein to prepare canthaxanthin route long for synthetic method, and cost is generally higher；The available strain of present stage biological fermentation process is less, and not easily cultivates, and the post-processing steps of fermentation is numerous and diverse, and extraction ratio is not high yet, is all unfavorable for industrialized production.Oxidizing process mainly with beta-carotene etc. for raw material, generates canthaxanthin through peroxidating, and conventionally used oxidant is iodate or periodate, chlorate, manganese dioxide, tin ash, hydrogen peroxide etc., and reaction is relatively violent, severe reaction conditions.And the dangerous property of oxidant itself, belong to hazardous chemical and poisonous and harmful substance such as hydrogen peroxide, in the eighties in 20th century, be found to have carcinogenecity, have substantial connection with various active oxygen associated diseases simultaneously；Sodium chlorate easily causes burning and blast, and aquatile is poisonous, and water body environment can produce long-term harmful effect, is all unfavorable for that industrialization cleaning produces.
The preparation method of the canthaxanthin that United States Patent (USP) 4212827 is mentioned, adopts halate under potassium iodide or iodine exist, aoxidizes beta-carotene.But the shortcoming that the method exists is exactly that initiated oxidation is more difficult, technique is unstable, uses more potassium iodide, and excessive oxidant needs to neutralize with sodium thiosulfate, and the difficulty of waste water or fixed-end forces is very big.
Summary of the invention
The invention provides a kind of method that oxidizing process prepares canthaxanthin, the method reaction condition is gentle, and will not produce substantial amounts of Halogen waste water, has fewer environmental impacts.
A kind of oxidizing process prepares the method for canthaxanthin, comprises the steps:
(1) beta-carotene is dissolved in halogenated hydrocarbon solvent, drips oxidizing agent solution under heating condition and carry out oxidation reaction, through washing after reacting completely, remove solvent and obtain thick oil；
Oxidant is one or both the mixture in thiourea peroxide and carbamide peroxide；
(2) the thick oil that step (1) obtains is dissolved in organic solvent, under heating condition, carries out transposition, process through later after transposition completely and obtain described beta-carotene.
The present invention adopts thiourea peroxide and carbamide peroxide as new oxidant, and reaction initiation is more prone to, and reaction condition is gentle.And compare with hydracid saline oxidizing agent, it is to avoid the generation of a large amount of Halogen waste water, environment is more friendly.
Concrete reaction equation is as follows:
In step (1), the efficiency of reaction can be produced large effect by reaction medium, and described halogenated hydrocarbon solvent includes at least one in dichloromethane, chloroform, 1,2-dichloromethane etc.；As preferably, described halogenated hydrocarbon solvent is dichloromethane.
The consumption of halogenated hydrocarbon solvent is without particularly severe requirement, and its weight is generally 20～40 times of beta-carotene.
As preferably, in step (1), the solvent of dissolved oxidant is polar solvent.As further preferably, described polar solvent is at least one in water, methanol, ethanol, propanol, isopropanol and THF.As further preferred, described polar solvent is water.
The consumption of polar solvent is generally 1:8～1:15 without the weight ratio of particularly severe requirement, oxidant and described polar solvent.
As preferably, the consumption of oxidant is 0.5～3 times of beta-carotene quality.
As preferably, the time for adding of oxidizing agent solution is 30～60 minutes.
As preferably, the temperature of oxidation reaction is 30～40 DEG C, and the response time is 8～16 hours.
By the thick oil that oxidation reaction obtains there being the double bond of portion of product be configured as Z formula structure, it is necessary to being translated into corresponding E formula structure, the using value of product is higher.
In step (2), the organic solvent dissolving thick oil is the conventional solvent of this area, for instance alcohol, ether, ketone, esters and their mixture.It is the mixture of any one or more in carbon molecular number alcohol within 6, ketone, ether and esters solvent as preferably described organic solvent.As further preferably, described organic solvent is methanol, ethanol one therein or its mixture, and now, the efficiency of transposition is high, and end-product easily crystallizes out from reaction system, and the product purity obtained is high.
The consumption of described organic solvent, without particularly severe requirement, is generally 8～20 times of beta-carotene weight.
As preferably, the temperature of transposition is 65～100 DEG C, and the time of transposition is 8～16 hours, and now, the efficiency of transposition is high, and in the product obtained, the content of E formula structure is higher.
As preferably, in step (2), described post processing carries out crystallization for being cooled to 10～25 DEG C.Crystallization at such a temperature, the product yield obtained is high.
The preparation method of canthaxanthin of the present invention, it is simple that its advantage has technological operation, stable reaction, and initiation conditions is gentle；Oxidant thiourea peroxide and carbamide peroxide can be analyzed to H in a solvent2O2And elemental oxygen, and slowly release O2, its active o content high stability is good, and the effectiveness time is long, has no side effect, Nonpoisonous, non-environmental-pollution, is advantageously implemented industrialization cleaning and produces.
Detailed description of the invention
Embodiment 1
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) thiourea peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 30 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 30 DEG C of insulation reaction 8 hours.Separate organic layer, washing extract 3 times, wash finish separate organic layer again.Organic layer rotary evaporation, thoroughly removes solvent, obtains 25g slightly oily.When HPLC, use AE.LICHROM-SiO2-5 (250mm*4.6mmSN:C14080401) post, mobile phase is normal hexane: acetone=95:5, and flow velocity is 1.5ml/min, detects under 470nm, and its (E)-isomer is 66.75%, and (Z)-isomer is 30.33%.Thick oil is dissolved in 300ml ethanol, it is warming up to infinite reflux, insulation reaction 8 hours, is cooled to 10 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 20.5g, yield is 68.9%, and content is 94.8%, uses HPLC to analyze, its (E)-isomer is 94.55%, and (Z)-isomer is 3.83%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.
Embodiment 2
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) thiourea peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 16 hours.Separate organic layer, washing extract 3 times, wash finish separate organic layer again.Organic layer rotary evaporation, thoroughly removes solvent, obtains 27.3g slightly oily.Thick oil is dissolved in 300ml ethanol, it is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 10 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 23.5g, yield is 79.25%, and content is 95.1%, uses HPLC to analyze, its (E)-isomer is 94.75%, and (Z)-isomer is 3.68%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.
Embodiment 3
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) thiourea peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 16 hours.Separate organic layer, washing extract 3 times, wash finish separate organic layer again.Organic layer rotary evaporation, thoroughly removes solvent, obtains 27.1g slightly oily.Thick oil is dissolved in 300ml methanol, it is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 25 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 24.6g, yield is 82.8%, and content is 94.9%, uses HPLC to analyze, its (E)-isomer is 94.66%, and (Z)-isomer is 3.71%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.
Embodiment 4
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) thiourea peroxide is put in 500ml beaker, adds 200ml methanol, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 16 hours.Reacting and finish, washing extracts 3 times, washes and finishes separation organic layer.Organic layer rotary evaporation, thoroughly removes solvent, obtains 22.6g slightly oily.Thick oil is dissolved in 300ml methanol, it is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 25 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 21.1g, yield is 71.3%, and content is 95.3%, uses HPLC to analyze, its (E)-isomer is 94.81%, and (Z)-isomer is 3.57%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.
Embodiment 5
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) carbamide peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 8 hours.Reacting and finish, washing extracts 3 times, washes and finishes separation organic layer.Organic layer rotary evaporation, thoroughly removes solvent, obtains 21.9g slightly oily.Thick oil is dissolved in 300ml ethanol, it is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 10 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 21.1g, yield is 71.0%, and content is 94.9%, uses HPLC to analyze, its (E)-isomer is 94.76%, and (Z)-isomer is 3.66%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.
Comparative example 1
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml petroleum ether and stirring and dissolve, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) thiourea peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 16 hours.Separate organic layer, washing extract 3 times, wash finish separate organic layer again.Organic layer rotary evaporation, thoroughly removes solvent, obtains 15.8g slightly oily.Thick oil is dissolved in 300ml methanol, is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 25 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 13.75g, content is 93.2%, and yield is 45.44%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.This comparative example shows, the yield of reaction can be produced large effect by the solvent dissolving beta-carotene.
Comparative example 2
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；22.6g (30%, 0.2mol) hydrogen peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 16 hours.Separate organic layer, washing extract 3 times, wash finish separate organic layer again.Organic layer rotary evaporation, thoroughly removes solvent, obtains 12.5g slightly oily.Thick oil is dissolved in 300ml methanol, is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 25 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 11.2g, content is 91.0%, and yield is 36.1%.The fusing point of obtained canthaxanthin solid is 206～208 DEG C.This comparative example shows, selecting of oxidant can to the yield generation large effect of reaction.
Comparative example 3
Take 26.8g (0.05mol) beta-carotene to put in 1000ml four-hole boiling flask, add 600ml dichloromethane stirring and dissolving, then four-hole boiling flask is put in water-bath and heat；21.6g (0.2mol) thiourea peroxide is put in 500ml beaker, adds 200ml water, dissolve under room temperature, dissolve after completely and be transferred in 250ml constant pressure funnel.When in four-hole boiling flask, temperature rises to 35 DEG C, starting to drip sulfuric peroxide urea solution, time for adding controls temperature in 1 hours, dropping process and must not exceed 40 DEG C, drips and finishes, 38 DEG C of insulation reaction 16 hours.Separate organic layer, washing extract 3 times, wash finish separate organic layer again.Organic layer rotary evaporation, thoroughly removes solvent, obtains 26.8g slightly oily.Thick oil is dissolved in 300ml oxolane, is warming up to infinite reflux, insulation reaction 16 hours, is cooled to 25 DEG C, crystallisation by cooling 3 hours, it is filtrated to get puce canthaxanthin solid 18.76g, content is 85.2%, and yield is 56.7%.Obtained canthaxanthin solid uses HPLC to analyze, and its (E)-isomer is 82.63%, and (Z)-isomer is 15.92%.As can be seen here, the solvent of transposition is different, the effect of transposition can be produced large effect.
Claims (10)
1. the method that an oxidizing process prepares canthaxanthin, it is characterised in that comprise the steps:
(1) beta-carotene is dissolved in halogenated hydrocarbon solvent, drips oxidizing agent solution under heating condition and carry out oxidation reaction, through washing after reacting completely, remove solvent and obtain thick oil；
Oxidant is one or both the mixture in thiourea peroxide and carbamide peroxide；
(2) the thick oil that step (1) obtains is dissolved in organic solvent, under heating condition, carries out transposition, process through later after transposition completely and obtain described beta-carotene.
2. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that in step (1), the solvent of dissolved oxidant is polar solvent.
3. the method that oxidizing process according to claim 2 prepares canthaxanthin, it is characterised in that described polar solvent is at least one in water, methanol, ethanol, propanol, isopropanol and THF.
4. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that the consumption of oxidant is 0.5～3 times of beta-carotene quality.
5. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that the time for adding of oxidizing agent solution is 30～60 minutes.
6. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that the temperature of oxidation reaction is 30～40 DEG C, the response time is 8～16 hours.
7. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that in step (2), described organic solvent is the mixture of any one or more in carbon molecular number alcohol within 6, ketone, ether and esters solvent.
8. the method that oxidizing process according to claim 7 prepares canthaxanthin, it is characterised in that described organic solvent is the one in methanol, ethanol or its mixture.
9. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that in step (2), the temperature of transposition is 65～100 DEG C, and the time of transposition is 8～16 hours.
10. the method that oxidizing process according to claim 1 prepares canthaxanthin, it is characterised in that in step (2), described post processing carries out crystallization for being cooled to 10～25 DEG C.
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Cited By (4)
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| CN107698478A (en) * | 2017-10-30 | 2018-02-16 | 上虞新和成生物化工有限公司 | It is a kind of to prepare the different methods for matching somebody with somebody oil viscosity bata-carotene |
| CN108101817A (en) * | 2017-12-23 | 2018-06-01 | 厦门金达威维生素有限公司 | The method that beta carotene oxidation prepares canthaxanthin |
| CN109369486A (en) * | 2018-12-18 | 2019-02-22 | 厦门金达威维生素有限公司 | A kind of preparation method of canthaxanthin |
| CN109369484A (en) * | 2018-11-22 | 2019-02-22 | 万华化学集团股份有限公司 | A method of canthaxanthin is prepared by beta carotene |
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