JPS6135839B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating crude sugar alcohol fatty acid esters. More specifically, crude sugar alcohol fatty acid ester containing fatty acid ester as an impurity is treated with a lipolytic enzyme in the presence of water with or without a reducing agent to hydrolyze the fatty acid ester. The present invention relates to a method for treating a crude sugar alcohol fatty acid ester, which is characterized by:

Sugar alcohol fatty acid esters have excellent surface activity, good biodegradability, and high safety, so they are used as surfactants that can fundamentally solve problems such as environmental pollution and toxicity to living organisms. recent years,
It is an extremely useful compound that is widely used as an additive for foods, cosmetics, pharmaceuticals, feed, and resins, metal processing oils, rust preventives, textile oils, etc.

Various methods are known for producing sugar alcohol-based fatty acid esters, among them a method in which sugar alcohols and fatty acids are directly esterified in the presence of a base catalyst, and a method in which sugar alcohols and fatty acid esters (usually lower A common method is to carry out alcoholysis in the presence of a base catalyst.

In particular, although the latter method is considered to be the most advantageous method for producing sugar alcohol fatty acid esters, it has not been widely adopted industrially. This is because the crude sugar alcohol fatty acid ester produced by the latter method contains unreacted sugar alcohols and by-product stones, as well as the target sugar alcohol fatty acid ester. Typically, it contains Ken and unreacted fatty acid esters, and conventional methods have been used to efficiently and economically advantageously remove these unreacted fatty acid esters. One of the main reasons is that little is known about it.

In other words, unreacted sugar alcohols and by-product soaps can be converted into sugar alcohols relatively easily and by methods that utilize differences in solubility in solvents or by converting them into derivatives such as calcium soaps. Although it is possible to remove fatty acid esters almost completely without substantial loss, unreacted fatty acid esters have chemical properties such as reactivity and physical properties such as solubility in solvents that are similar to sugar alcohol fatty acids. Esters, especially sugar alcohol-based fatty acid esters that have two or more ester bonds in one molecule, are very similar to each other, so if you try to remove unreacted fatty acid esters more completely, you will inevitably need to remove a wide variety of sugar alcohol-based fatty acid esters. The major drawback is that loss of fatty acid ester cannot be avoided.

The present inventors have conducted various studies to overcome the deficiencies of conventional methods mainly based on chemical or physical methods, and as a result, we have developed a crude sugar alcohol-based fatty acid ester containing fatty acid esters as impurities. By treating with a lipolytic enzyme in the presence of water, only the impurity fatty acid esters are selectively separated from the corresponding fatty acids and alcohols, without substantial loss of sugar alcohol fatty acid esters. They discovered that it can be hydrolyzed into , and completed the present invention.

Next, the present invention will be explained in detail.

Sugar alcohol fatty acid esters to be used in the method of the present invention include tetritols such as erythritol and threitol, which have 4 hydroxyl groups, pentitols, such as ribitol, arabitol, and xylitol, which have 5 hydroxyl groups, and pentitols, which have 6 hydroxyl groups. Sugar alcohols represented by hexitols such as allitol, sorbitol, mannitol, dulcitol, ideitol, and altritol, heptitols such as boremitol, sedoheptitol, and perseitol, which have 7 hydroxyl groups, and maltitol and lactitol, which have 9 hydroxyl groups. or at least one dehydrated cyclized product of a sugar alcohol represented by sorbitan, sorbide, mannitan, mannide, etc., which has a cyclic ether core produced by intramolecular dehydration and cyclization of these sugar alcohols, and a fatty acid. All sugar alcohol fatty acid esters that have one or more ester bonds in the same molecule are subject to the target. In particular, sorbitol fatty acid ester, mannitol fatty acid ester, sorbitan fatty acid ester, mannitan fatty acid ester, etc. are sugar alcohol fatty acid esters to which the method of the present invention can be applied advantageously and suitably, since they are inexpensive and can be used for a wide range of purposes. .

Furthermore, the fatty acid component that is a component of the sugar alcohol fatty acid ester is usually one having 6 to 24 carbon atoms. These fatty acid components may be either saturated fatty acids or unsaturated fatty acids, and their carbon chains are not limited to linear ones, but may also be branched ones. Furthermore, it may have a substituent such as a hydroxyl group.

Typical fatty acids include caproic acid, caprylic acid, capric acid, lauric acid,
Examples include myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid, elaidic acid, arachidic acid, behenic acid, and lignoceric acid.

In addition, as impurity fatty acid esters, alcohols selected from the group consisting of aliphatic lower monohydric alcohols, aliphatic lower dihydric alcohols, and aliphatic lower trihydric alcohols, and the above-mentioned fatty acids having 6 to 24 carbon atoms are used. The target esters are: Specific examples of alcohols that are constituent components of these fatty acid esters include methanol, ethanol, propanol, butanol carbitol (dieterene glycol mono-lower alkyl ether), ethylene glycol mono-lower alkyl ether, ethylene glycol, and propylene. Typical examples include glycol, butanediol, glycerin, and trimethylolpropane.

Among the fatty acid esters mentioned above, fatty acid esters of methanol, ethanol, and glycerin are used when producing sugar alcohol fatty acid esters.
Since it is often used as one of the main raw materials, it is the fatty acid ester that is most likely to be contained as an unreacted product in the crude sugar alcohol fatty acid ester that is the object of the present invention.

Furthermore, among the aforementioned fatty acid esters, fatty acid esters of aliphatic lower dihydric alcohols include monoesters and diesters, and fatty acid esters of aliphatic lower trihydric alcohols include monoesters, diesters, and triesters. However, the method of the present invention is not limited to monoesters, but also diesters,
This also applies to triesters.

There is no particular restriction on the ratio of sugar alcohol fatty acid ester to fatty acid ester in the crude sugar alcohol fatty acid ester used in the method of the present invention, and any composition can be used.

The method of the present invention can be applied to any crude sugar alcohol-based fatty acid ester containing the aforementioned fatty acid esters as impurities, regardless of its manufacturing method, history, content of each component, etc. In addition to the above, fatty acid alkali metal salts, fatty acid alkaline earth metal salts, fatty acid ammonium salts,
Soaps such as fatty acid organic amine salts, sugar alcohols, intramolecular dehydrated cyclized products of sugar alcohols such as sorbitan, sorbide, mannitan, mannide, fatty acids and aliphatic lower monohydric alcohols, aliphatic lower dihydric alcohols, aliphatic lower Alcohols such as trihydric alcohol, salts, and other substances may be contained as impurities as long as they do not interfere with the function of enzymes.

When treating crude sugar alcohol-based lipoprotective acid esters with a lipolytic enzyme in the presence of water, with or without a reducing agent,
Various methods can be employed, but usually, crude sugar alcohol fatty acid esters are used as they are, or some or all of the coexisting sugar alcohols, soaps, fatty acids, alcohols, salts, etc. are mixed with known methods. After removing the fatty acid esters in advance according to the method, water is added to dissolve or suspend them in water to prepare an aqueous solution or suspension, and then a lipolytic enzyme is added to hydrolyze the fatty acid esters. The most common method is to Incidentally, the typical method is to add the reducing agent at the same time as the addition of the lipolytic enzyme, but any other arbitrary method can also be adopted.

The amount of water added is usually such that the concentration of the crude sugar alcohol fatty acid ester is 1 to 90% by weight, more preferably 5 to 70% by weight, and most preferably 10 to 50% by weight. is good. If the amount of water added is too large, a large amount of energy is required to remove the water afterwards, which is uneconomical, and if the amount of water added is too small, the viscosity of the aqueous solution or suspension will increase. Both are undesirable because they increase the temperature and make it difficult to fully exhibit the effects of the present invention.

Typical examples of lipolytic enzymes include acylglycerol lipase, including acylglycerol lipase derived from Rhizopus, acylglycerol lipase derived from Aspergillus, acylglycerol lipase derived from Mucoa, acylglycerol lipase derived from Pseudomonas, and acylglycerol lipase derived from Candida. , pancreatic acylglycerol lipase, and the like.

Furthermore, the lipolytic enzyme does not necessarily have to be purified acylglycerol lipase;
As long as it has lipolytic activity and does not decompose sugar alcohol fatty acid esters, it can be used regardless of its purity.

Further, although a reducing agent is not particularly required, the combined use of a reducing agent generally tends to promote the action of lipolytic enzymes.

Typical examples of the reducing agent include sodium dithionite, vitamin C, cysteine, glutathione, 2-mercaptoethanol, sodium sulfite, sodium thiosulfate, and hydroquinone.

These lipolytic enzymes and reducing agents are added to the above-mentioned aqueous solution or suspension of the crude sugar alcohol fatty acid ester, either as they are or after previously dissolved in water or the like.

The amount of lipolytic enzyme and reducing agent used varies depending on the type and content of fatty acid esters in the crude sugar alcohol fatty acid ester, but the amount used depends on the potency of the lipolytic enzyme itself. 0.0001 to 20% by weight, more preferably 0.0005 to 10% by weight, most preferably 0.0001 to 5% by weight, based on the crude sugar alcohol fatty acid ester)
As for the weight percent and the reducing agent, as mentioned above, it is not necessary to use it, but if it is used, it is 2% to the crude sugar alcohol fatty acid ester.
It is preferably at most 1% by weight, more preferably at most 1% by weight, and most preferably at most 0.5% by weight. If the amount of the lipolytic enzyme used is less than the lower limit above, it will be difficult to fully exhibit the effects of the present invention, and if it is used in an amount greater than the upper limit, no special advantage will be exhibited, and on the contrary, Both are unfavorable because they are uneconomical.

Lipid-degrading enzymes (including when combined with reducing agents)
The pH and temperature conditions are most important when processing crude sugar alcohol fatty acid esters using
Although it depends on the type and characteristics of the lipolytic enzyme used, the pH is usually adjusted to 2 to 10, more preferably 4 to 9, and most preferably 5 to 8. PH regulators include formic acid, acetic acid, propionic acid, oxalic acid, succinic acid, maleic acid, glycolic acid, lactic acid, malic acid, tartaric acid, citric acid, benzoic acid, methanesulfonic acid, benzenesulfonic acid, hydrochloric acid, and sulfuric acid. , acids such as phosphoric acid, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, calcium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, calcium oxide, ammonia, methylamine, triethylamine, aniline, pyridine, Bases such as morpholine and triethanolamine, and salts such as acid salts and basic salts are used.

Also, the temperature is usually 10 to 80°C, more preferably 20 to 80°C.
It is best kept at 60°C, most preferably between 25 and 50°C.

If the pH and temperature are outside the above ranges, the action of lipolytic enzymes will be suppressed, and especially under strongly acidic or basic conditions and at high temperatures, sugar alcohol fatty acid esters will be inhibited. This is not preferable because pure chemical hydrolysis reaction by its own acid or base catalyst tends to occur simultaneously.

The time required to process crude sugar alcohol fatty acid esters and hydrolyze fatty acid esters using a lipolytic enzyme depends on the amount, type, potency, and characteristics of the lipolytic enzyme used, the type of fatty acid ester, Although it varies depending on the content and whether or not a reducing agent is used together, it is usually about 30 minutes to 100 hours, more preferably 1 to 70 hours, and most preferably about 3 to 50 hours.

By employing suitable treatment conditions using the lipolytic enzymes described above, most or almost all of the fatty acid esters in the crude sugar alcohol fatty acid ester are finally hydrolyzed into fatty acids and alcohols. Ru.

Highly purified sugar alcohol fatty acid esters can be easily obtained from the thus obtained lipolytic enzyme-treated solution by appropriately combining known methods such as solvent extraction, crystallization, conversion of fatty acids into other derivatives, and removal. It is possible to obtain.

As detailed above, according to the method of the present invention,
Fatty acid esters in crude sugar alcohol fatty acid esters can be selectively hydrolyzed into easily separated fatty acids and alcohols, and loss of sugar alcohol fatty acid esters can be substantially prevented. The treatment method of the present invention is extremely useful industrially.

The present invention will be explained in more detail with reference to Examples below.

Example 1 80 g of water was added to 20 g of crude sorbitol tallow fatty acid ester consisting of 75% by weight of sorbitol tallow fatty acid ester (monoester/diester = 60/40 weight ratio) and 25% by weight of beef tallow fatty acid triglyceride and mixed well (mixture (pH 6.5), 0.04 g of Lipase M AP-10 [Acylglycerol lipase derived from Mucoa, manufactured by Amano Pharmaceutical Co., Ltd.] was added,
The treatment was carried out for 40 hours with stirring at a temperature of 40°C.

A portion of the treated solution was collected, freeze-dried, and then quantitatively analyzed using gas chromatography. As a result, the fatty acid ester contained only 0.5% by weight of beef tallow fatty acid monoglyceride, and no beef tallow fatty acid triglyceride or beef tallow fatty acid diglyceride was detected. Nakatsuta.

Furthermore, by comparing the results of quantitative analysis by gas chromatography of the sorbitol tallow fatty acid ester content before and after the treatment with Lipase M AP-10, it was found that the sorbitol tallow fatty acid ester was not substantially decomposed. found.

Example 2 Sorbitan oleate (monoester/diester = 70/30 weight ratio) 50% by weight and oleic acid triglyceride (also known as triolein) 50% by weight
Add 70 g of water to 30 g of crude sorbitan oleate ester consisting of
PH6.6), then lipase AP-4 [Amano Pharmaceutical Co., Ltd.]
0.12 g of Aspergillus-derived acylglycerol lipase produced by Aspergillus Co., Ltd. was added, and the treatment was carried out at 35° C. for 24 hours with stirring. A portion of the treated solution was collected and quantitatively analyzed in the same manner as in Example 1. As a result,
As the fatty acid-protecting esters, only 3.6% by weight of oleic acid monoglyceride was contained, and oleic acid triglyceride and oleic acid diglyceride were not detected. It was also found that sorbitan oleate was not substantially decomposed.

Example 3 Mannitol monolaurate 70% by weight
and 25 g of crude mannitol fatty acid ester consisting of 30% by weight of lauric acid methyl ester and 75 g of water.
Lipase M AP-10 0.025 to the mixture (PH6.3)
g and 1 g of a 0.01% by weight aqueous vitamin C solution were added, and the treatment was carried out for 10 hours while stirring at a temperature of 35°C.

A portion of the treated solution was collected and quantitatively analyzed in the same manner as in Example 1. As a result, the content of lauric acid methyl ester was 1.2% by weight, and 96% of the lauric acid methyl ester initially present was It was found that it was hydrolyzed to lauric acid and methanol.

It was also found that mannitol monolaurate was not substantially decomposed.

Example 4 Mannitan stearate (monoester/diester = 70/30 weight ratio), 60% by weight, mannin 10% by weight, potassium stearate 10% by weight
After adjusting the pH to 6.0 by adding 1/10 normal hydrochloric acid to a mixture of 20 g of crude mannitan stearate and 80 g of water (PH9.3) consisting of 20% by weight of ethyl stearate and lipase P [ Amano Pharmaceutical
Co., Ltd., Pseudomonas-derived acylglycerol
Lipase] 0.02g and glutathione 0.1% by weight
0.1 g of an aqueous solution was added and the treatment was carried out for 24 hours with stirring at a temperature of 45°C. A portion of the treated solution was collected and quantitatively analyzed in the same manner as in Example 1. As a result,
The content of stearic acid ethyl ester was 0.1% by weight, and it was found that 99.5% of the stearic acid ethyl ester initially present was hydrolyzed to stearic acid and ethanol.

It was also found that mannitan stearate was not substantially decomposed.

Example 5 Crude sorbitol coconut fatty acid ester obtained by alcoholysis of sorbitol and coconut oil (coconut fatty acid triglyceride) in the presence of a potassium base catalyst (sorbitol monococonut fatty acid ester 28% by weight, sorbitol dicoconut fatty acid ester 13) Weight%, coconut fatty acid triglyceride 2% by weight, coconut fatty acid diglyceride 6% by weight, coconut fatty acid monoglyceride 8% by weight
Add 60 g of water to 40 g (containing 43 wt. % of sorbitol, potassium coconut fatty acid acid, glycerin, etc.) and mix well (pH of the mixture is 9.7). Then, add citric acid to the mixture to make the pH 6.2. Adjusted to. Subsequently, 0.12 g of Lipase M AP-10 was added, and 37
The treatment was carried out for 20 hours at a temperature of °C. After processing
The pH was 5.6.

A portion of the treated solution was collected and quantitatively analyzed in the same manner as in Example 1. As a result, the content of coconut fatty acid monoglyceride was 1.1% by weight, and coconut fatty acid diglyceride and coconut fatty acid triglyceride were not detected.

It was also found that the sorbitol coconut fatty acid ester was not substantially decomposed.

Example 6 Xylitol monolaurate 60% by weight
0.15 g of lipase P was added to a mixed solution (PH 6.5) of 30 g of crude xylitol monolaurate containing 40% by weight of coconut oil and 70 g of water, and the mixture was treated at a temperature of 45° C. for 24 hours. As a result, the pH after the treatment was 5.9. A portion of the treated solution was collected and quantitatively analyzed using the same method as in Example 1. As a result, the content of coconut fatty acid monoester was 1.4.
% by weight, and coconut fatty acid diglyceride and coconut fatty acid triglyceride were not detected. It was also found that xylitol monolaurate was not substantially decomposed.

Example 7 Maltitol stearate (monoester/diester/triester = 50/30/20 weight ratio) 40% by weight and oleic acid triglyceride 60%
Add 0.04 g of Lipase M AP-10 and Lipase P0.08 to a mixture of 40 g of crude maltitol stearate and 60 g of water (PH6.7) containing % by weight.
g was added and the treatment was carried out at a temperature of 37° C. for 48 hours. A portion of the treated solution was collected and quantitatively analyzed in the same manner as in Example 1. As a result, the content of oleic acid monoglyceride was 2.2% by weight, and oleic acid diglyceride and oleic acid triglyceride were not detected. Furthermore, since only a trace amount of stearic acid was detected in the quantitative analysis results of maltitol stearate ester by a method similar to Examples 1 to 6 and gas chromatography, maltitol stearate ester was substantially decomposed. It was proven that they did not.

Claims (1)

[Claims] 1. Crude sugar alcohol fatty acid ester containing fatty acid esters as impurities is treated with a lipolytic enzyme in the presence of the following, with or without a reducing agent, to produce fatty acid esters. A method for processing a crude sugar alcohol fatty acid ester, which comprises hydrolyzing a crude sugar alcohol fatty acid ester. 2. The method for treating crude sugar alcohol fatty acid esters according to claim 1, wherein the fatty acid esters are glycerin fatty acid esters. 3. The method for treating crude sugar alcohol fatty acid esters according to claim 1, wherein the fatty acid esters are fatty acid esters of aliphatic lower monohydric alcohols. 4. The method for treating crude sugar alcohol fatty acid ester according to claim 1, wherein the sugar alcohol fatty acid ester is a sugar alcohol fatty acid ester. 5. The method for treating a crude sugar alcohol fatty acid ester according to claim 1 or 4, wherein the sugar alcohol fatty acid ester is a sorbitol fatty acid ester. 6. The method for treating a crude sugar alcohol fatty acid ester according to claim 1 or 4, wherein the sugar alcohol fatty acid ester is a mannitol fatty acid ester. 7. The crude sugar alcohol according to claim 1, wherein the sugar alcohol fatty acid ester is a fatty acid ester of a dehydrated cyclized sugar alcohol having a cyclic ether core produced by intramolecular dehydration and ring closure of the sugar alcohol. Processing method for fatty acid esters. 8. The method for treating a crude sugar alcohol fatty acid ester according to claim 1 or 7, wherein the sugar alcohol fatty acid ester is a sorbitan fatty acid ester. 9. The method for treating a crude sugar alcohol fatty acid ester according to claim 1 or 7, wherein the sugar alcohol fatty acid ester is a mannitan fatty acid ester. 10 A patent claim in which the crude sugar alcohol fatty acid ester contains as impurities, in addition to fatty acid esters, at least one compound selected from the group consisting of sugar alcohols, soaps, fatty acids, and monohydric to trihydric alcohols. A method for treating a crude sugar alcohol fatty acid ester according to Scope 1. 11. Claim 1 or 1, wherein the crude sugar alcohol fatty acid ester is a reaction product obtained by alcoholysing a sugar alcohol and a fatty acid ester in the presence of a base catalyst.
A method for treating a crude sugar alcohol fatty acid ester according to item 0. 12. Claim 1, wherein the reducing agent is at least one compound selected from the group consisting of sodium dithionite, vitamin C, cysteine, glutathione, 2-mercaptoethanol, sodium sulfite, sodium thiosulfate, and hydroquinone. The method for treating the crude sugar alcohol fatty acid ester described. 13. The method for treating crude sugar alcohol fatty acid esters according to claim 1, wherein the lipolytic enzyme is acylglycerol lipase.