JPS606992B2 - Method for producing natural essential oils without phototoxicity - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims to remove the causative substance from a natural perfume oil containing bergapten, which causes harmful effects on the skin (photogenicity), by analyzing the aroma, color tone, component balance, yield, etc. of the natural essential oil. The present invention relates to a method for producing natural essential oils that are industrially advantageous and have excellent quality and do not have phototoxicity, without adversely affecting the environment.

Natural essential oils are widely used as fragrances for perfumes, colognes, creams, lotions, lotions, lipsticks, white powders, foundations, pomades, hair creams, and other perfumery products.

However, bergamot oil, lime oil, lemon oil,
It is well known that bergapten, which is contained in natural essential oils such as orange oil and grapefruit oil, has phototoxicity.

Conventionally, the method for removing coumarin-containing compounds such as bergapten has been to obtain a distilled essential oil by distilling natural bergamot oil under reduced pressure at a temperature that does not change the components of bergamot oil, while distilling the distillation residue. is hydrolyzed with an alcoholic alkali, furocoumarins are removed by converting the hydrolyzate into an alkali salt form, and the remaining neutral oil is combined with the above-mentioned crab extract essential oil, which causes irritation to the skin. A proposal has been made (Samurai Kosho 35-115363) to produce bergamot essential oil that does not give off.

However, in this method, the alkali during hydrolysis tends to cause side reactions (oxidation, polymerization, isomerization, decomposition, etc.) of the useful neutral oil components other than bergapteso, and the aroma and color of natural perfume oils , deterioration of component balance, etc.
It has been pointed out that there are many technical defects, such as coloring and aroma modulation (Tokukan Sho 55-13434 Publication, page 2, left column).

As another method, lemon oil is distilled under reduced pressure at a temperature that does not change the components of lemon oil to obtain crab extract essential oil, while the distillation residue is cooled in the presence of a nonpolar solvent to obtain the residue. A method for producing a natural essential oil that does not contain psoralen compounds, which is characterized by crystallizing and removing psoralen compounds from the liquid, and combining the essential oil obtained by removing a nonpolar solvent from the residual liquid with the above-mentioned candied essential oil. has been proposed (Tokusekki Sho 55 "No. 3434"). However, it is difficult to sufficiently remove bergapten with this method (extraction from the distillation residue), and this fact is reflected in the above-mentioned improved invention. This is clear from the fact that Hakama Seki No. 56-70096 has been proposed.

As a result of intensive research aimed at developing a method for producing non-phototoxic natural essential oil from natural essential oil containing bergapten, the present inventors have found that the distillation residue of natural essential oil containing bergapten is subjected to reduction treatment as described below. In this case, bergapten is converted into a compound without optical properties, and the component extracted with an organic solvent from the reduction treatment mixture (distillation residue obtained in the third step below) is converted into distilled essential oil obtained in the first step below. The present invention was completed based on the discovery that a natural essential oil of excellent quality and without phototoxicity can be obtained by combining the natural essential oil with the following: without adversely affecting the aroma, color tone, component balance, yield, etc. of the natural essential oil.

Therefore, the object of the present invention is to use Belgaff. An object of the present invention is to provide a method for industrially easily producing a high-quality natural essential oil that does not substantially contain bergapten and has no phototoxicity from a natural essential oil containing ten. Many other objects and advantages of the invention will become more apparent from the description below. The present invention comprises a first step of distilling a natural essential oil containing bergapten under reduced pressure to obtain a distilled essential oil that does not substantially contain bergapten; The second stage involves dissolving it in a lower monohydric alcohol and performing a reduction treatment, and '3} Adding an organic solvent to the resulting mixture after the reduction treatment and extracting it, washing the obtained extract with water, dehydrating it, and then a third step of removing the organic solvent in the extract;
This is a method for producing a natural essential oil without optical properties, which is characterized by comprising a fourth step of mixing the distilled essential oil collected in the first step with the distilled essential oil.

Hereinafter, embodiments of the present invention will be explained in detail.

Examples of natural essential oils containing bergapten that can be used in the method of the present invention include bergamot oil, lemon oil, orange oil, lime oil, grapefruit oil, mandarin oil, and petitculen oil.

0 In the first step, in the distillation of the natural essential oil containing bergapten under reduced pressure conditions, the degree of reduced pressure and temperature are appropriately selected so as to obtain a natural essential oil that does not substantially contain bergapten without altering the natural essential oil. You can do it by doing this.

Evening Generally, conditions can be adopted that do not impair the aroma of the essential oil components contained in the natural essential oil, such as a temperature of 125q.
0 or less, the degree of decompression is approximately 1 ratio per day, and the conditions are adopted.

Generally, it is preferable to select a lower temperature and reduced pressure. Further, the amount of distillation is selected depending on the content of bergapten in the natural essential oil, but generally, the amount of distillation is about 95% by weight based on the natural essential oil.

It is best to distill as much as possible without sacrificing the aroma.
The crab extract essential oil obtained by vacuum distillation in the first stage as described above is mixed with the distillation residue obtained in the third stage, but is stored until then.

The distillation residue obtained in the first step is dissolved in a saturated aliphatic lower monohydric alcohol (solvent), and then sodium borohydride or sodium borohydride as a reducing agent and nickel boride are added to the solution. Then, the reduction process is carried out (
2nd stage). By this reduction treatment, bergapten, which is contained in a relatively large amount (approximately 3 to 6% by weight) in the distillation residue of the first stage, can be converted into a compound without optical properties.

Examples of the saturated aliphatic lower monohydric alcohol that dissolves the distillation residue include methyl alcohol, ethyl alcohol, and n-phthalate.

Examples of the alcohol include propyl alcohol, inpropyl alcohol, n-butyl alcohol, isobutyl alcohol, n-amyl alcohol, and isoamyl alcohol. The amount of the lower monohydric alcohol used is preferably in the range of 5 times to 1 pip to the weight of the distillation residual bamboo. In the reduction treatment, a reducing agent, sodium borohydride alone or together with nickel boride, is added to the alcohol solution of the distillation residue, usually 0.1 to 0.2 times the weight of the distillation residue, and 40q. ○ within the range of the reflux temperature of the alcohol,
It is performed by praying to a hawk for about 5 to 7 hours.

Bergapten is not substantially present in the product mixture after the reduction treatment, and, for example, even when analyzed by high performance chromatography, no bergapten peak is observed.

In the present invention, the distillation residue from the first stage may be subjected to reduction treatment as described above, but if necessary, as another method (addition step), the total distillation residue from the first stage may be dissolved in a nonpolar solvent. After that, the solution is cooled, the precipitated solid matter is separated and removed (furnace separation), and the residual liquid (furnace liquid) is distilled to remove the nonpolar solvent.The distillation residue is then distilled as described above. It may be dissolved in the lower alcohol and subjected to reduction treatment.

Implementation of this additional step increases the number of steps, but has the advantage that the time required for the reduction treatment is shortened because the content of bergapten in the distillation residue is reduced. Incidentally, examples of the nonpolar solvent that can be used in this addition step include petroleum benzene, petroleum benzene, n-hexane, n-pentane, isobentane, n-octane, and cyclohexane.

The amount used is 1 to 5% based on the weight of the distillation residue in the above step.
Double weight is preferred. Further, the temperature at which the nonpolar solvent solution of the distillation residue in the first stage is cooled is 1000 or less, preferably 0.
00 or less is preferable.

In addition, vacuum distillation is preferably used as the distillation for distilling off the nonpolar solvent from the residual liquid after separating and removing the precipitated solid matter.
The product mixture after the reduction treatment in the second stage is distilled to remove the saturated aliphatic lower monohydric alcohol contained therein, then a hydrophobic solvent is added to the residue for extraction, and the extract is washed with water. After dehydration, the extract is distilled to remove the hydrophobic solvent contained therein (third step).

In this third step, distillation for distilling off (recovering) the saturated aliphatic lower monohydric alcohol and the hydrophobic solvent from each of the solutions is preferably vacuum distillation.

As the hydrophobic solvent (extraction solvent) added to the residue after removing the saturated aliphatic lower monohydric alcohol, for example, ethyl ether, methyl ethyl ether, benzene, chloroform, methylene chloride, etc. are preferable.

Extraction with the hydrophobic solvent can be sufficiently carried out by conventional extraction operations.

This extract is washed with water in order to decompose and remove the remaining reducing agent dissolved in the extract, but the pH of the extract layer is
It is important to wash thoroughly with water until it becomes neutral. Since the washed extract contains a small amount of water, it is desirable to add an appropriate amount of an inert dehydrating agent such as anhydrous sodium sulfate to sufficiently dehydrate it. The hydrophobic solvent extract after dehydration is distilled to remove the hydrophobic solvent, and this distillation is also preferably distilled under reduced pressure. The distillation residue (pale yellow oil) after removing the hydrophobic solvent by this distillation is added to the distilled essential oil collected in the first step and mixed (combined).
and make it into a product. (Fourth step) The purified natural essential oil obtained in this way is substantially colorless and transparent, has no foreign odor, and retains the aroma of the natural essential oil without any loss.
It has a scent rich in so-called naturalness.

Moreover, it is not irritating to the skin and has no optical properties at all. Furthermore, it does not contain not only bergapten, which is known as a phototoxic component, but also oxyboisedanin and the above-mentioned psoralens. For example, even by high performance liquid chromatography analysis, no peaks of these optical components are observed. According to the method of the present invention, high-quality natural essential oils with high utility value and without optical properties can be produced with high reproducibility without adversely affecting the aroma, color tone, and component balance (useful essential oil components) of the natural essential oils. Obtained in high yield,
The specificity of its action and effect is remarkable.

Example 1 Bergamot oil 1.0k9 containing 1.8% (weight) of bergabten was distilled under reduced pressure to obtain 0.96k9 colorless oil (crab essential oil) as distillate oil up to 70°C/2 side Hg. Ta.

As a result of high performance liquid chromatography analysis of this colorless oil, no bergapten peak was observed. Next, 40 g of this distillation residue and 277 g of methyl alcohol were added as a solvent, and after dissolving, 4.0 g of sodium borohydride was gradually added to the solution over a period of 1 hour. Thereafter, the mixture was heated under reflux for 4 hours. After carrying out the reduction treatment described above, the methyl alcohol was removed by distillation of the starch mixture under reduced pressure. As a result of high performance liquid chromatography analysis of this distillation residue, no peak of bergapten was observed.
Next, 300 ml of ethyl ether was added to the remaining solution after distillation, and the ethyl ether layer of the extract was washed with water until the pH of the ethyl ether layer became neutral. After that, anhydrous sodium sulfate was added to the extract to dehydrate it. Ethyl ether was distilled off.

Distillation residue thus obtained (pale yellow oil) 20.0
The purified bergamot oil was added to the distillate essential oil obtained earlier and mixed to obtain purified bergamot oil 980 g. As a result of high performance liquid chromatography analysis of this purified bergamot oil, bergapten, oxypoisedanine and psoralen (psoralen, 4-methylpsoralen, 4,4-dimethylpsoralen, 4.5-dimethylph) were found.

Psoralen, 4', 8-dimethylpsoralen, 4, 5, 8
-trimethylpsoralen, 8-methoxypsoralen, 5
-Methoxypsoralen peaks were not observed.
Further, a sensory test was repeated 10 times by 10 expert inspectors regarding the smell of this refined bergamot oil and the commercially available bergamot oil (bergapten-containing bergamot oil).

As a result, 9 out of 10 people confirmed that there was no difference in aroma between the two samples. In addition, this refined bergamot oil
As a result of conducting a phototoxicity test as described below, it was confirmed that there was no phototoxicity.

Phototoxicity Test Method The back of a white rabbit weighing 2.5-3 kg was shaved, and after 2 hours, 50% of a diluted solution of the sample in ethanol was applied in 2 rows on a 2x2 plate.

One case was covered with aluminum foil and exposed to UV-A3 (32
40 m) were irradiated for 1 hour.

The light source used was 10 Toshiba BLB lamps equipped with a glass filter. The amount of energy at this time is 30×1
It was 07ergs/. The evaluation was based on the following scores for erythema and edema immediately after irradiation, 2 hours after irradiation, and 48 hours after irradiation. Rating No macroscopic change 0 Mild or sparse erythema 1 Moderate erythema
2-intensity erythema and edema
The reaction between the area irradiated with 3UV-A and the area not irradiated was compared, and the case where the reaction of the irradiated area was strong was judged to be optically sensitive (10).

The average reaction intensity was calculated as follows. Total average reaction intensity of each rabbit rating = Number of rabbits used in the experiment Test results: In the table, the numbers in parentheses in the UV (1) and UV (10) sections indicate the average intensity, and the denominator The number in the numerator represents the number of domestic rabbits used in the experiment, and the number in the numerator represents the number of domestic rabbits that responded to the stimulus.

Table 1 Samples Level UV (1) UV (10) Phototoxic bergamot oil 50% 10 no 10 (3.0) 5/lo (
o. 5) Existence (Ichiba Kinuta) 25 10/10 (3.0) 0
ノ10 Yes10 10ノ10(2.5)0ノ10
5 10 no 10 (2.0) 0 no 10 Refining of 1 50 3 no lo (o.3) 3 no lo, o
, 3) No base oil 25 0 no 10 0 no 10
No 10 0 no 10 0 no 10 No 5
0 no 10 0 no 10 None As a result, commercially available bergamot oil has a significant photogenic effect, but no phototoxicity was detected in the purified bergamot oil according to Example 1 of the present invention.

Example 2 The bergamot oil of Example 1 was distilled under reduced pressure in the same machine, and 70
Distillate oil up to qo/2 skin Hg (distillate essential oil of colorless oil)
0.96 kg and 40.0 kg of distillation residue were obtained.

Add 40 g of this distillation residue to 316 g of methyl alcohol, add 40 g of nickel boride previously obtained from nickel chloride and sodium borohydride, and add 4.5 g of sodium borohydride little by little over 1 hour. 40℃
Add ~50qo while stirring. After the addition, the mixture was heated under reflux for 4 hours. Thereafter, the methyl alcohol was removed under reduced pressure, and the residue was extracted with 300 parts of chloroform. After adding water to this extract and washing with water until the pH of the chloroform layer became neutral, anhydrous sodium sulfate was added and dehydrated.
Chloroform is distilled off under reduced pressure. The obtained residue (pale yellow oil) 25 kg was thoroughly mixed with the previously obtained distilled essential oil 0.96 k9 to obtain purified bergamot oil pseudo 5 kg. As a result of carrying out the same procedure as in Example 1, it was confirmed that this purified bergamot oil did not contain bergapten, oxypoisedanine, and psoralen.

Furthermore, optical accuracy was not detected as shown in Table 2. Furthermore, as a result of the sensory test regarding odor, 10 out of 10 people confirmed that there was no difference in aroma compared to commercially available bergamot oil (untreated, containing bergapten oil). Table 2 Concentration UV (1) UV (10) Phototoxic Fragrance 5
0 3-10 (0.3) 3〆lo (o.3) None Good * Concentration % UV (1) UV (10) Phototoxic fragrance 25 0 of 10 0〆10
None 〃10 0〆10 0〆10
None 〃5 o no lo OKIO
None Example 3 Example 1 except that each alcohol shown in Table 3 below was used instead of methyl alcohol.
Refined bergamot oil was produced in the same manner as above.

Yield, yield, optical aroma of each refined bergamot oil obtained,
The results of aroma properties are shown in Table 3.

In addition, each distilled essential oil of bergamot oil is 960
It was evening. Also, "good aroma" means that no difference was observed in the aroma compared with the commercially available bergamot oil used. From the results shown in Table 3 and above, it was confirmed that saturated aliphatic lower monohydric alcohol is preferable as the solvent for the distillation residue in the reduction treatment.

Example 4 Bergamot oil 1 containing 0.3% by weight of bergapten
．． 0k9 was distilled under reduced pressure to obtain 0.96 kg of crabmeat essential oil (colorless oil) as crabmeat oil at a temperature of up to 70°C/2 Hg.

Next, 40% of petroleum ether was added to 40% of this distillation residue, and the mixture was cooled to 0°C. The precipitated crystals and insoluble matter are separated in a furnace, and the petroleum ether is removed under reduced pressure. To the residue after removing the petroleum ether, 237 g of methyl alcohol is added as a solvent, and 2.4 g of sodium borohydride is added little by little over 1 hour at a temperature of 40 to 50 qC. After the addition, the mixture was heated under reflux for 4 hours. Thereafter, the resulting mixture was distilled under reduced pressure to remove methyl alcohol. Next, the residue is extracted with 300 ml of ethyl ether, washed with water until the pH of the ethyl ether layer becomes neutral, and after dehydration with anhydrous sodium sulfate, the ethyl cable is removed.

Residue after removing ethyl ether (slight yellow oil)
The refined bergamot oil 979 was added to the previously obtained bergamot essential oil 960 and mixed. This purified bergamot oil was examined in the same manner as in Example 1, and it was confirmed that it did not contain bergapten, oxyboisedanin, and psoralen.

Also, no photogenicity was detected. In addition, as a result of a sensory test regarding odor, 10 out of 10 people confirmed that there was no difference in aroma compared to the commercially available bergamot oil. Example 5 Lime oil 1.0 containing 0.25% by weight of bergapten
K9 was distilled under reduced pressure to obtain a distillate essential oil (colorless oil) of 960 g as a distillate oil with a concentration of up to 7000/2 Hg.

Next, 40 g of this distillation residue and 300 g of petroleum ether are added, and the mixture is cooled to 0.degree. The precipitated crystals and insoluble matter are separated by furnace,
The petroleum ether is removed under reduced pressure. To the residue after distilling off the petroleum ether, 237 g of ethyl alcohol was added as a solvent, and to this was added 2.4 g of sodium borohydride little by little at 40 qC to 50 C for 1 hour. Add while doing so. After addition, heat to reflux for 4 hours. Thereafter, the ethyl alcohol was distilled off under reduced pressure, and the residue was dissolved in 300% of benzene.
The benzene Z layer is extracted with water, washed with water until the pH of the benzene Z layer becomes neutral, dehydrated with anhydrous sodium sulfate, and then the benzene is removed under reduced pressure. Next, this residue (pale yellow oil) (15 minutes) was added to the previously obtained distillate essential oil 960 and mixed with Nawa Azusa to obtain refined lime oil 975 minutes. This refined lime oil was examined in the same manner as in Example 1, and it was confirmed that it did not contain bergapten or psoralen.

Also, no photogenicity was detected. In addition, as a result of a sensory test regarding the smell, 9 out of 10 people said that the lime oil (
It has been confirmed that there is no difference in aroma compared to (untreated). Example 6 1.0 kg of lime oil containing 0.25% by weight of bergapten was distilled and 7000/2 Willow H
Crab extract essential oil 960 g was obtained as crab extract oil.

Next, 237 g of ethyl alcohol and 4.0 g of nickel boride were added to the distillation residue, and then 2.49 g of sodium borohydride was added little by little over 1 hour to give 40 to 5,000 ml of ethyl alcohol.
After addition, the mixture was refluxed for 4 hours while stirring.

Thereafter, ethyl alcohol was distilled off under reduced pressure. Next, the residue was extracted with 300 g of benzene, and the extract was washed with water until its pH became neutral, then dehydrated with anhydrous sodium sulfate, and the benzene was distilled off under reduced pressure. A pale yellow oil (20%) was obtained. A total of 20 g of this distillation residue was added to 960 g of the previously obtained distilled essential oil and mixed well to obtain a refined lime oil with no spots. As a result of examining this refined lime oil in the same manner as in Example 1, it was confirmed that it did not contain bergapten and psoralen, and that it did not have optical properties.

It was also confirmed that there was no difference in aroma compared to the lime oil used. Example 7 Bergapten was added to 0.
Orange oil 1.0k9 containing 0.04% by weight was distilled under reduced pressure to obtain 970 kg of clear and colorless crab extract essential oil (orange oil) as a distillate oil with a skin Hg of 7000/2.

Add 300 g of petroleum ether to this distillation residue,
Cool to 0°C. The precipitated crystals and insoluble matter are separated in a furnace, and the petroleum ether is removed under reduced pressure. To the residue after distilling off the petroleum ether, add 270 ml of methyl alcohol, and add 20 ml of sodium borohydride little by little to 400 ml in 1 hour.
○～500○ Add while pressing down. After addition, heat to reflux for 4 hours. Thereafter, the methyl alcohol was distilled off under reduced pressure, and the residue (25 mm) was extracted with 300 mm of ethyl ether and washed with water until the ethyl ether layer became neutral. This extract was dehydrated over anhydrous sodium sulfate, and the ethyl ether contained therein was distilled off under reduced pressure to obtain a distillation residue (reddish brown oil).

20 minutes of this distillation residue was added to the crab extract essential oil 970 g obtained earlier and mixed well to obtain purified orange oil 995 g. As a result of high performance liquid chromatography analysis of this purified orange oil, neither a bergapten peak nor a psoralen peak was observed.

In addition, as a result of conducting a photogenicity test in the same manner as in Example 1, no photogenicity was detected. Additionally, 10 out of 10 expert inspectors confirmed that there was no difference in aroma compared to the orange oil used. Example 8 Bergapten was added to 0. Lemon oil containing 1.0k9% by weight was distilled under reduced pressure to obtain 965cm colorless oil as an essential oil distilled to 7000/2 Hg.

Next, 35 ml of distillation residue and 277 ml of ethyl alcohol were added as a solvent, and further 20 ml of sodium borohydride was added little by little over 1 hour at a temperature of 40° C. to 50 qo. Thereafter, the mixture is further heated under reflux for 4 hours. After that, ethyl alcohol was distilled off, and the residue was 30% benzene.
Extract with [0]. Next, the extract is washed with water until it becomes neutral, then dehydrated with anhydrous sodium sulfate, and the extract is distilled under reduced pressure to remove benzene. The obtained distilled essential oil 965 mm was mixed well to obtain purified lemon oil 980 mm.As a result of high-speed chromatography analysis of this refined lemon oil, no peaks of bergapten, oxypoisedanine, and psoralen were observed. In addition, as a result of conducting the photoplexus test in the same manner as in Example 1, no photogenicity was detected.As for the odor, 10 out of 10 expert inspectors found that it was fragrant compared to the lemon oil used. We have confirmed that there is no difference.

Example 9 The same lemon oil 1.0k9 as in Example 8 was distilled under reduced pressure, and 70
00/2 Colorless oil as distillate essential oil up to Kite Hg 965
I got the evening.

Next, add 35 ml of distilled residue and 277 ml of methyl alcohol. Next, 3.5 ml of nickel boride prepared from nickel chloride and sodium borohydride was added to this solution, and then 2.0 ml of sodium borohydride was added little by little over 1 hour, and the mixture was heated at 40oC to 5000°C. Add while doing so.
After addition, heat to reflux for 4 hours. Thereafter, methyl alcohol was distilled off from the resulting mixture under reduced pressure, and the residue was extracted with 300 g of ethyl ether, and the extract (ethyl ether layer)
After washing with water until the pH becomes neutral, dehydrate with anhydrous sodium sulfate. After removing the ethyl ether under reduced pressure, 25.0 g of the pale reddish brown oil obtained as the distillation residue was thoroughly mixed with the previously obtained 965 g. of the crab extract essential oil to obtain 990 g. of refined lemon oil. As a result of comparing this refined lemon oil in the same machine as the refined lemon oil obtained in Example 8, it was found that it did not contain bergapten, oxypoisedanine, and psoralen.
It has also been confirmed that it does not have optical meaning.

It has also been confirmed that there is no difference in smell compared to the lemon oil used.

Claims (1)

[Scope of Claims] 1 (1) A first step of distilling a natural essential oil containing bergapten under reduced pressure conditions to collect a distilled essential oil that does not substantially contain bergapten; (2) distillation residue; a second step of dissolving in a saturated aliphatic lower monohydric alcohol and performing a reduction treatment in the presence of sodium borohydride or in the coexistence of sodium borohydride and nickel boride; (3)
A third stage in which the saturated aliphatic lower monohydric alcohol is distilled off from the product mixture after the reduction treatment, the residue is extracted with a hydrophobic solvent, the extract is washed with water, dehydrated, and the hydrophobic solvent is distilled off. and (4) a fourth step of mixing the distillation residue after distilling off the hydrophobic solvent with the distilled essential oil collected in the first step, to produce a natural essential oil that does not have phototoxicity. manufacturing method. 2 Between the first and second stages, a non-polar solvent is added to the distillation residue obtained in the first stage and cooled to separate and remove the precipitated solids, and then the remaining liquid is distilled to form a non-polar solvent. 2. The manufacturing method according to claim 1, which comprises the step of distilling off the organic solvent and collecting the distillation residue.