JPH0533987B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing fats and oils, and more particularly to a method for producing fats and oils containing a large amount of long-chain highly unsaturated fatty acids. In the present invention, long-chain highly unsaturated fatty acids mean fatty acids having 20 or more carbon atoms and 3 or more double bonds per molecule, and hereinafter referred to as PUFA.
It is abbreviated as [Prior Art] PUFA has recently attracted attention for its physiological activity and pharmacological effects on humans, and active studies have been conducted on the use of PUFA. [Problems to be solved by the present invention] However, since PUFA has a high boiling point, high vacuum and high temperatures are required to recover it, which increases energy costs. It has been pointed out that there is an increase in the amount of undesirable isomers produced due to an increase in the number of undesirable isomers due to an increase in the yield and a decrease in the yield. In view of the above-mentioned problems, an object of the present invention is to provide a process that can efficiently obtain fats and oils containing a large amount of PUFA. [Means for Solving the Problems] The method for producing fats and oils of the present invention uses long-chain polyunsaturated fatty acids (PUFA) containing 5 to 30% eicosapentaenoic acid (EPA) and 3 to 15% docosahexaenoic acid (DHA). ) using lipase.
It is hydrolyzed to selectively hydrolyze fatty acids other than PUFA, and 10-50% of EPA is extracted from the hydrolyzate.
The glyceride containing long-chain polyunsaturated fatty acids containing 5 to 30% DHA is fractionated, and the obtained long-chain polyunsaturated fatty acid-containing glyceride is treated as long-chain polyunsaturated fatty acid, long-chain polyunsaturated fatty acid ester, or By esterifying or transesterifying with mixed fatty acids and mixed fatty acid esters containing these, EPA can be increased to 15%.
50% and 7 to 30% DHA. [Function] The PUFA-containing fats and oils used in the present invention include, for example, fish oil, whale oil, krill oil, marine chlorella oil, etc., but mixed oils, conjugated isomerized oils, partially hydrogenated oils, etc. containing these fats and oils can also be used. be able to. In the method of the present invention, these fats and oils are hydrolyzed using lipase so as to selectively hydrolyze fatty acids other than PUFA, thereby producing glycerides containing PUFA. The lipase used in the present invention includes:
There are fatty acid selective lipases and regiospecific lipases. What is fatty acid selective lipase?
It is a lipase that selectively hydrolyzes fatty acids other than PUFA, such as lipases of the genus Candida and Geotricum. In addition, position-specific lipases are those used for oils and fats containing glycerides that have fatty acids other than PUFA at specific positions, such as Rhizopus lipase and Aspergillus lipase. . The amount of these lipolytic enzymes to be used is preferably 100 to 5000 U (unit) per 1 g of reaction substrate (oil), expressed as U (units) representing fat and oil hydrolyzing activity. The amount of water added is preferably 5 to 500% (by weight, same hereinafter), more preferably 10 to 200%, based on the fat or oil. The pH of water is preferably in the range of 4.5 to 8.5, and it is more effective to use a buffer to adjust the pH, with a particularly desirable pH range of 5.5 to 8.0. Furthermore, for a more effective reaction,
Emulsifiers such as polyvinyl alcohol and fatty acid esters can also be used, and addition of bile salts is also effective in increasing hydrolysis activity. The hydrolysis reaction may be carried out in the atmosphere, but if it contains a large amount of long-chain highly unsaturated acids, such as fish oil or whale oil, it may be carried out under an inert gas atmosphere, such as nitrogen gas or carbon dioxide atmosphere. Leaving it for a long time not only prevents deterioration of fatty acids, but also prevents enzyme deactivation. Also, antioxidants, such as tocopherols,
TBHQ, BHA, and BHT may be used together. The hydrolysis reaction is preferably carried out at 20-60°C. Below 20°C, the reaction is slow, and above 60°C, the enzyme is inactivated. It is more preferable to carry out the reaction at a temperature of 30 to 45°C. Further, although it is preferable to stir the reaction, it is also possible to leave the reaction in an emulsified state and allow the reaction to stand still. Further, the reaction may be a single-stage reaction, but may also be a multi-stage reaction in order to proceed more efficiently and quickly. An immobilized enzyme column can also be used for continuous reaction. In addition, in the hydrolysis reaction of the present invention, a monohydric alcohol and/or an inert solvent can be used to improve the hydrolysis rate. The above monohydric alcohol is an aliphatic alcohol having 1 to 28 carbon atoms, such as methanol, ethanol, propanol, butanol, hexanol, octanol, decanol, dodecanol, hexadecanol, octadecanol, tetracosanol, hexacosa alcohol, particularly preferred are butanol, octanol, decanol, dodecanol,
Hexadecanol, octadecanol, etc.
The amount added is 0.1 to 20 moles per mole of oil or fat. In addition, hexane, petroleum ether, etc. are used as inert solvents, and the amount used is 10% of the oil or fat.
It is not more than 3 times, preferably not more than 3 times. Continue like this for 0.5-20 hours (preferably 2-20 hours)
10 hours) Perform the hydrolysis reaction, and finally the decomposition rate
20-80% reaction product is obtained, preferably 40-60%. To separate PUFA-containing glycerides from such reaction products, chromatography, fractional crystallization,
Known methods such as fractional distillation and liquid-liquid distribution can be used. Any fatty acid or fatty acid ester can be used for esterification or transesterification with the PUFA-containing glyceride obtained in Fatty acids or mixed fatty acid esters are preferred. Although esterification and transesterification can be carried out using acid or alkali catalysts, it is highly preferable to use lipase for the purposes of the present invention. As the lipase used for esterification and transesterification, lipases of the genus Rhizobus, Aspergillus, Mucor, Candeida, Diotrichum, etc. can be used alone or in combination. The amount of lipase used is 50 to 1 g of substrate (fatty acid + alcohol + alcohol ester).
3000U, preferably 100-1000U. Esterification and transesterification reactions are preferably carried out using water and an organic solvent that does not inactivate enzymes, and in an inert gas atmosphere such as N ₂ or CO ₂ to prevent oxidation of fatty acids. Water is 0.1-10% relative to the substrate, organic solvents such as hexane and petroleum ether are relative to the substrate.
It is recommended to use 0.3 to 10 times, preferably 0.5 to 5 times. The amount of alcohol or alcohol ester used may range from 0.1 to 20 moles per mole of fatty acid, and a dehydrating agent or the like is present in the esterification and transesterification reaction system to allow the reaction to proceed while dehydrating. is preferable. The reaction is preferably continued at a reaction temperature of 30 to 50°C for 5 to 80 hours, usually 5 to 40 hours. In the esterification or transesterification reaction of the present invention, it is preferable to add a monohydric alcohol having 1 to 28 carbon atoms because the reaction proceeds rapidly. The above monohydric alcohols include, for example, methanol,
Ethanol, propanol, butanol, hexanol, octanol, decanol, dodecanol, hexadecanol, octadecanol, tetracosanol, hexacosanol, etc., and particularly preferred are butanol, octanol,
decanol, dodecanol, hexadecanol,
Octadecanol etc. Moreover, the amount added is 0.1 to 10 mol per 1 mol of PUFA-containing glyceride. The enzyme used in the present invention can be immobilized or adsorbed on a suitable inert support for convenience such as reuse or recovery. Such inert supports include celite, alumina, chitosan, and the like. [Effect of the invention] In the method for producing fats and oils of the present invention, EPA (eicosapentaenoic acid), which is a type of PUFA, was contained in the raw material fats and oils at a concentration of 5 to 30%, but after hydrolysis, the glyceride contains EPA (eicosapentaenoic acid). 10-50% (preferably 15-35
%), for fats and oils after esterification or transesterification.
15-50% (preferably 25-45%). In addition, GHA (docosahexaenoic acid), which is also a type of PUFA, was contained in the raw material fats and oils at a concentration of 3 to 15%, but it is similarly contained in the glyceride after hydrolysis at a concentration of 5 to 30% (preferably 5 to 20%). %), and the oil or fat after esterification or transesterification contains 7 to 30% (preferably 10 to 25%). As described above, according to the method of the present invention, fats and oils containing a large amount of PUFA can be efficiently obtained. [Examples] The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. Example 1 1Kg of fish oil (IV=182.1, EPA 14%, DHA
11%), lipase derived from the genus Lipase Candeida (trade name "Lipase OF", manufactured by Meito Sangyo Co., Ltd.) 30
Add 1,000 g of ion-exchanged water containing 1,000 U, and heat at 35℃.
Hydrolysis was carried out with stirring for 4 hours. After the reaction, oil was separated from the hydrolyzate by centrifugation. The acid value of the obtained oil was 98.9. This oil was fractionated with acetone, and then fatty acids and glyceride portions were fractionated with methanol. This glyceride part (Example-
The fatty acid composition of 1A) is EPA 20.1%, DHA 16.2
%, and the yield was 52%. This glyceride part
50g and concentrated long chain unsaturated fatty acids (EPA 45%,
Mix 50g of DHA (20%), add 20,000 U of Rhizopus derma together with a small amount of water, and add hexane.
Transesterification reaction in 100g for 12hr with dehydration
I did it. The triglyceride part (Example-1B) was extracted from this reaction product by column chromatography.
When fractionated, the yield was 35g, and the methyl esterified GLC composition was 29.8% EPA and 19% DHA. The reaction rate was (80%). The fatty acid compositions of the glyceride part obtained by fractionating the above hydrolyzed oil (Example 1A) and the triglyceride part obtained by transesterification (Example 1B) were as shown in Table 1. Example 2 The same operation as in Example 1 was carried out except that 20 g of decyl alcohol was added to the transesterification reaction. The triglyceride portion of the obtained product is 37g
The yield is 31.5% EPA, DHA in fatty acid composition.
It was 19.3%. The fatty acid composition is shown in Table-1.

[Table] Therefore, for example, c20:5ω3 is a fatty acid with 20 carbon atoms and has 5 double bonds, of which the first double bond is the third fatty acid counting from the terminal methyl group.

Claims (1)

[Claims] 1 5-30% eicosapentaenoic acid (EPA),
Oils and fats containing long-chain polyunsaturated fatty acids (PUFA) containing 3 to 15% docosahexaenoic acid (DHA) are hydrolyzed using lipase to selectively hydrolyze fatty acids other than PUFA, resulting in a hydrolysate. Glycerides containing long-chain highly unsaturated fatty acids containing 10-50% EPA and 5-30% DHA are separated from
The obtained long-chain highly unsaturated fatty acid-containing glyceride is esterified or transesterified with a long-chain highly unsaturated fatty acid, a long-chain highly unsaturated fatty acid ester, a mixed fatty acid containing these, or a mixed fatty acid ester to obtain an EPA of 15 to 15%. A method for producing fats and oils, characterized by obtaining a long-chain highly unsaturated fatty acid alcohol ester containing 50% DHA and 7 to 30% DHA.