JPS5837838B2 - Purification method of sugar fatty acid ester - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for purifying sugar fatty acid esters.

More specifically, the present invention relates to a method for removing and purifying fatty acid glycerides from crude sugar fatty acid esters containing at least fatty acid glycerides as impurities.

Sugar fatty acid esters have high biodegradability and safety, so they have recently been used as surfactants to fundamentally solve environmental pollution and toxicity problems for living organisms, and have been used as additives in foods, cosmetics, pharmaceuticals, resins, etc. It is an extremely useful compound that is being developed for a wide range of uses, including detergents, laundry detergents, kitchen detergents, and shampoos.

Various methods are known for producing sugar fatty acid esters, but among them, the method using alcoholysis between sugar and fatty acid lower alkyl ester and the method using alcoholysis between sugar and fat or oil, that is, fatty acid triglyceride, are excellent. There is.

In particular, the latter method is an extremely advantageous method for producing sugar fatty acid esters, since comparatively inexpensive animal and vegetable fats and oils such as beef tallow, palm oil, and coconut oil can be used as they are as raw material fats and oils.

The reaction product obtained by this method contains, in addition to sugar fatty acid esters, fatty acid glycerides (usually a mixture of unreacted fatty acid triglycerides, fatty acid diglycerides, and fatty acid monoglycerides), soap, and unreacted free sugars. Therefore, it is necessary to remove these impurities and purify the sugar fatty acid ester.

Among these impurities, soaps and free sugars can be easily removed without substantial loss of sugar fatty acid esters by converting them into other derivatives or by utilizing differences in solubility in solvents. It is possible to remove it completely.

On the other hand, regarding the removal of fatty acid glycerides, conventionally known methods include solid-liquid extraction using organic solvents such as acetic acid esters and ketones. Because the difference in solubility in organic solvents between sugar-fatty acid polyesters having ester bonds and fatty acid glycerides is small, it is extremely difficult to completely separate the two. It has a major defect in that it causes loss of ester.

The present inventors have made intensive studies to overcome the deficiencies of the conventional methods.
The present inventors have discovered that fatty acid glycerides can be easily removed without substantial loss of sugar fatty acid esters by decomposing fatty acid glycerides using a lipolytic enzyme and a reducing agent, and have completed the present invention.

Next, the present invention will be explained in detail.

Sugar fatty acid esters used in the method of the present invention include arabinose, xylose, ribose, glycose (glucose), mannose, galactose, fructose (fructose).
, maltose, cellobiose, trehalose, kenthiobiose, isomaltose, lactose, sucrose, raffinose, gentianose, maltotriose, stachyose, xylan,
A sugar fatty acid ester that is an ester of a monosaccharide, disaccharide, trisaccharide, tetrasaccharide, or polysaccharide and a fatty acid having 6 to 24 carbon atoms, such as alaban cellulose and starch, and has one or more ester bonds in the same molecule. are all included.

In particular, sucrose fatty acid ester is one of the sugar fatty acid esters to which the method of the present invention can be most suitably applied.

Further, the fatty acid glyceride is any one of fatty acid triglyceride, fatty acid diglyceride, or fatty acid monoglyceride derived from a fatty acid having 6 to 24 carbon atoms, or
It is a mixture of two or more types.

The crude sugar fatty acid ester to which the method of the present invention is applied is
Contains at least the above-mentioned fatty acid glyceride as an impurity, and also includes soaps such as sodium soap, potassium soap, amine soap, and calcium soap, free fatty acids,
It is also applicable to crude sugar fatty acid esters containing free sugars, glycerin, inorganic salts, etc.

These crude sugar fatty acid esters may be used as they are, or after some or all of the coexisting soaps, free sugars, etc. have been removed in advance, water is added to dissolve or suspend them in water.

The amount of water added is usually such that the concentration of crude sugar fatty acid ester is 1
It is preferably added in an amount of ~90% by weight, preferably 5-70% by weight, and more preferably 10-50% by weight.

If the amount of water added is too large, it will take a lot of energy to remove the water afterwards, which is economically disadvantageous, and if the amount of water added is too small, the aqueous solution of crude sugar fats and acid esters will be The viscosity increases and mixing with the lipolytic enzyme and reducing agent becomes insufficient, making it difficult to fully exhibit the effects of the present invention, both of which are unfavorable.

Typical examples of lipolytic enzymes include acylglycerol rehase, including acylglycerol lipase derived from Rhizopus, acylglycerol rehase derived from Aspergillus, and acylglycerol derived from Mucoa.
Lipase Examples include acylglycerol lipase derived from Pseudomonas, acylglycerol lipase derived from Candida, and acylglycerol lipase derived from pancreas.

Furthermore, the lipolytic enzyme is not necessarily a purified acylglycerol lipase, and any enzyme that has lipolytic activity and does not decompose sugar fatty acid esters can be used.

In addition, the reducing agent specifically includes sodium dithionite,
Examples include vitamin C1 glutathione, 2-mercaptoethanol, sodium sulfite, sodium thiosulfate, and hydroquinone.

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

When decomposing fatty acid glycerides in crude sugar fatty acid esters using lipolytic enzymes and reducing agents, pH and temperature are most important.

The pH depends on the type of lipolytic enzyme used, but is usually 2 to 10, preferably 3 to 9.5, and more preferably 4 to 9.
It is best to adjust it to

As the pH adjuster, common acids, alkalis, salts, etc. are used.

Further, the temperature is usually 10 to 70°C, preferably 20 to 60°C.
More preferably, the temperature is maintained at 25 to 50°C.

If the pH and temperature are in a range other than the above, the action of lipolytic enzymes and reducing agents will be suppressed, and if the pH and temperature are in a range other than the above, the
Under strongly alkaline conditions and at high temperatures, the hydrolysis reaction of the sugar fatty acid ester itself by the acid-base catalyst is accelerated, which is not preferable.

The amount of lipolytic enzyme and reducing agent used varies depending on the content of fatty acid glyceride in the crude sugar fatty acid ester, but
The amount of lipolytic enzyme (the amount used depends on the potency of the lipolytic enzyme itself) is 0.0001 to 20% by weight, preferably 0.0005 to 1% by weight, based on the crude sugar fatty acid ester.
0% by weight, more preferably 0.001 to 5% by weight, and as for the reducing agent, 0.0% by weight based on the crude sugar fatty acid ester.
000001-0.2% by weight, preferably 0.00000
5-0.1% by weight, more preferably 0.00001-0.
05% by weight.

If the amount of the lipolytic enzyme and reducing agent used is less than the above lower limit value, 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 value, it will become uneconomical. , both are unfavorable.

The time required to decompose fatty acid glycerides in crude sugar fatty acid esters using a lipolytic enzyme and a reducing agent is usually 30 minutes to 50 hours, preferably 1 hour to 40 hours, and more preferably 3 to 30 hours. It is.

By employing the above-mentioned suitable decomposition conditions using a lipolytic enzyme and a reducing agent, most or almost all of the fatty acid glycerides contained in the crude sugar fatty acid ester are finally converted into free fatty acids. It is broken down into glycerin.

After decomposing fatty acid glycerides, highly pure sugar fatty acid esters can be easily obtained by appropriately combining known purification methods such as filtration, conversion of free fatty acids to other derivatives, solvent extraction, and recrystallization.

As detailed above, according to the method of the present invention, fatty acid glycerides in crude sugar fatty acid esters containing at least fatty acid glycerides as impurities can be selectively decomposed into free fatty acids and glycerin, which are extremely easy to separate. Furthermore, it is possible to substantially prevent the loss of sugar fatty acid esters, so it is extremely advantageous industrially as a method for purifying sugar fatty acid esters.

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

Example 1 Sucrose monolaurate 14fI, Sucrose dilaurate 6
and trilaurin (glycerine trilaurate) 10
Add dilute acetic acid aqueous solution dropwise to a mixture of 1
H5. After adjusting to 5, lipase AP4 [manufactured by Amano Pharmaceutical ■] 0.02S' and 0.1% by weight aqueous solution of sodium dithionite 0.41? was added, and decomposition was carried out for 5 hours while slowly stirring in a constant temperature bath at 37°C.

A portion of the decomposition solution was carefully collected, and the resulting heptalauric acid was quantitatively analyzed by neutralization titration (a separate blank test was conducted) using an alcohol standard solution of potassium hydroxide with phenolphthalein as an indicator. It was found that 96% of trilaurin was hydrolyzed to lauric acid.

Incidentally, as a result of quantitatively analyzing a portion of the separately collected decomposition liquid by gas chromatography, no decomposition of sucrose monolaurate and sucrose dilaurate was observed.

Example 2 Lipase M-APIO (manufactured by Amano Pharmaceutical ■) 0.004? and vitamin C 0.01 to a mixture of 6 g of sucrose monostearate, 4 S' monoolein (glycerin monoole) and 90 g of water. A 0.81 wt % aqueous solution was added and decomposition was carried out at 37°C for 5 hours in the same manner as in Example 1. As a result of analysis, 95% of monoolein was hydrolyzed to oleic acid, and sucrose monostearate was hydrolyzed to oleic acid. No decomposition was observed.

Example 3 7 grams of sugar monostearate, beef tallow (saponification value 192m)
9KOH/? )3S', potassium oleate 51 and water 85t? A dilute acetic acid aqueous solution was added dropwise to the mixed solution to adjust the pH to 8, and then 0.6 g of a 0.1 wt% aqueous solution of pancreatin (manufactured by Amano Pharmaceuticals), 0.06 f of pancreatin (manufactured by Amano Pharmaceuticals), 0.0061 of lipase M-APIO, and glutathione was added. was added and decomposed for 2 hours while continuing to slowly stir in a constant temperature bath at 40°C.
As a result of the analysis, 96% of the beef tallow was hydrolyzed into the corresponding fatty acids, and no decomposition of sucrose monostearate was observed.

Example 4 Sucrose monolaurate 9.0 units, sucrose dilaurate 3 units
．． 8. Monolaurin (glycerin monolaurate) 3
2g, dilaurin (glycerine dilaurate) 2, 4g, trilaurin (glycerine trilaurate) 1.2P
, a dilute acetic acid aqueous solution was added dropwise to a mixture of 14.02% potassium laurate, 6.41% sucrose, and 601% water to adjust the pH to 7.5.
After adjusting to 0.014f of lipase MAPIO and 0.1% by weight aqueous solution of mercaptoethanol. 2 8
f was added and decomposed for 5 hours while slowly stirring in a constant temperature bath at 30°C, and then an aqueous potassium hydroxide solution was added to the decomposed liquid to convert fatty acids in the decomposed liquid to potassium soap. After converting the potassium soap into calcium soap by subsequently adding calcium chloride, most of the water was distilled off under reduced pressure to obtain a wet cake.

Next, 200 rnl of inpropanol was added to the wet cake for extraction.

After drying the obtained inpropanol extract over anhydrous sodium sulfate, ingropanol was distilled off under reduced pressure to obtain 13.2f of a white solid.

Composition analysis by gas chromatography and liquid chromatography revealed that sucrose monolaurate was 67%.
, 27% sucrose dilaurate, 1% free sucrose and 5% monolaurin, and the total purity of sucrose monolaurate and sucrose dilaurate was 94%.

Furthermore, when the purification yields of sucrose monolaurate and sucrose diurarate are calculated from these results, they are 98.3% and 9%, respectively.
It was 3.8%.

Claims (1)

[Claims] 1. A method for purifying a crude sugar fatty acid ester containing at least fatty acid glyceride as an impurity, the method comprising decomposing the fatty acid glyceride using a lipolytic enzyme and a reducing agent in the presence of water.