JPS6019955B2 - Method for producing natural essential oil with excellent aroma and no phototoxicity - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an industrially easy method for producing a natural essential oil with excellent aroma and no phototoxicity from a natural essential oil containing bergapten, which causes harmful effects (phototoxicity) on the skin. It relates to a manufacturing method that can be advantageously produced.

Natural essential oils are used in perfumes, colognes, creams, lotions, lotions, lipsticks, white powders, foundations, pomades,
It is widely used as a fragrance for perfumery products such as hair creams and hair creams.

However, bergamot oil, lime oil, lemon oil,
Bergapten, which is contained in natural essential oils such as orange oil and grapefruit oil, has a photogenic effect that causes skin irritation when exposed to sunlight, so it should not be used in fragrance products that are applied directly to the skin, such as perfumes and creams. bergapten must be removed.

Conventionally, one of the methods for removing bergapten from the natural essential oil is so-called distillation, in which the natural essential oil is distilled under reduced pressure and separated into cannibal essential oil, which does not contain bergapten, and distillation residue, which contains bergapten. The law is known.

However, in this distillation method, some of the necessary aroma components and bergabten in natural essential oils are removed as a distillation residue, so the obtained crab extract essential oil has poor odor retention and a satisfactory odor. However, it has many drawbacks such as low essential oil yield.

As a method to improve these drawbacks, distilled natural essential oil is treated chemically or physicochemically as described below to remove bergapten, and the remaining essential oil components (neutral oil) are removed.
A method has been proposed for producing a natural essential oil that does not contain bergapten by mixing (returning) bergapten into the crab extract essential oil (Japanese Patent Publication No. 35-15363, Japanese Patent Publication No. 56-170096). .

However, in the method described in Samurai Publication No. 35-15363, useful neutral oil components other than bergapten undergo side reactions (oxidation, polymerization, , isomerization, etc.), resulting in deterioration of the aroma, color tone, component balance, etc. of the obtained bergamot oil, and it has also been pointed out that it is difficult to avoid a decrease in purity and yield (Tokukan Sho 55-34).
34, page 196, left column). Also, JP-A-56-70
In the method described in Publication No. 096, a nonpolar solvent is added to the distillation residue of lemon oil, furocoumarins such as bergapten are insolubilized and precipitated, and then removed by adsorption to an inorganic adsorbent. These steps of distilling off to obtain purified lemon oil are very long and complicated, the yield is low, and it is not easy to remove furocoumarins sufficiently.

As a result of intensive research aimed at solving the problems of the prior art as described above, the inventors of the present invention have found that by blending the specific psoralen derivative described below with the natural essential oil (original oil) containing bergapten. The aroma and color of natural essential oils,
We discovered that it is easy to obtain natural essential oils that have a higher aroma intensity than raw essential oils or distilled essential oils, have a better odor than distilled essential oils, and have no optical properties, without adversely affecting the component balance. Completed the invention.

An object of the present invention is to provide a method for industrially easily producing natural essential oils that have excellent aroma and do not have optical properties.

Further objects and advantages of the present invention will become more apparent from the following description.

That is, in the present invention, natural essential oil containing bergapten is distilled under reduced pressure to collect crab extract essential oil that does not contain bergapten, and then 5-heptyloxypsoralen, 5-2-ethylhexyloxypsoralen, The present invention is a method for producing a natural essential oil having excellent aroma and no optical properties, characterized by incorporating at least one psoralen derivative selected from the group consisting of 5-octyloxypsoralen.

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

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

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 bergapteso (kanide essential oil) without altering the natural essential oil. You can do it by doing this.

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 1290 degrees or lower and a degree of vacuum of IQ or lower Hg.

Generally, it is preferable to select a lower temperature and reduced pressure.

Further, the distillate base obtained by distillation is selected depending on the bergapten content in the natural essential oil, but generally a distillate base of about 95% by weight based on the natural essential oil used is employed. It is best to let the crab come out as much as possible without compromising the aroma. When the natural essential oil is distilled under appropriate conditions as described above, belgabuteso in the natural essential oil remains in the distilled koji bamboo together with high-boiling aroma components and is separated from the distilled essential oil as a distillation residue. The crab extract essential oil thus obtained does not contain not only bergapten but also oxypoisedanine and psoralen as described below, and has no optical properties at all.

Next, blending of at least one of the psoralen derivatives into the distillate essential oil is usually carried out by adding an appropriate amount of at least one of the psoralen derivatives to the distillate essential oil and uniformly dissolving it. .

The amount used (blended amount) of at least one of the psoralen derivatives is 0.3 to 3% by weight, preferably 1 to 2% by weight, based on the weight of the distilled essential oil.

- 5-heptyloxypsoralen (hereinafter referred to as compound-4) used in the present invention, . 5-2
-Ethylhexyloxypsoralen (hereinafter referred to as Compound-5) and 0 and 5-octyloxypsoralen (hereinafter referred to as Compound-6) are both non-phototoxic, safe for animal skin irritation, and easily absorbed by the natural essential oil. It is melting.

Below, various properties of the compound of the present invention are shown. Table 1:
In the psoralen derivative of the present invention, the compound-4 is synthesized by reacting (alkylating) bergaptol with heptyl bromide in dimethylformamide in the presence of anhydrous potassium carbonate.

The compound-5 is synthesized by the same reaction as the compound-4 except that 2-ethylhexyl bromide is used instead of heptyl bromide. The compound-6 is synthesized by the same reaction as the compound-4 except that octyl bromide is used instead of heptyl bromide. The natural essential oil obtained by the method of the present invention is substantially colorless and transparent, retains the aroma of the natural essential oil without impairing it, and has a scent rich in so-called naturality.

Furthermore, its residual sound quality is superior to that of the distilled essential oil or the natural essential oil that has been prepared under reduced pressure. It also smells better than distilled essential oils and has no skin irritation or phototoxicity. Furthermore, not only bergapten, which is known as a component with photosensitivity, but also oxypoisedanine (Tokukan Sho 56-700
No. 96) and psoralen (Japanese Unexamined Patent Publication No. 55-34)
(described in Publication No. 34). 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 excellent lingering properties, good smells, and no phototoxicity can be obtained without adversely affecting the aroma, color tone, and component balance (useful essential oil components) of the natural essential oils. It can be easily obtained industrially with good reproducibility, and its action and effect are highly specific. Examples will be described below.

% shown in Examples means % by weight.

In addition, the test methods for lightness, lightness, etc. are as follows. Phototoxicity Test Method The back of a white rabbit weighing 2.5-3k9 was shaved, and after 2 hours, 50 ml of the diluted sample in ethanol was applied in two rows on a 2x2 arc.

One case was covered with aluminum foil and irradiated with UV-A (32 m to 40 m) for 1 hour after 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 a beer bag/me. Evaluation was made according to the following ratings for erythema and edema immediately after irradiation, 2 hours after irradiation, and 4 hours after irradiation.
Rating No macroscopic change 0 Mild or sparse erythema 1 Moderate erythema 2 Severe erythema and edema 3 Compare the reaction between the UV-A irradiated area and the non-irradiated area, and if the irradiated area has a strong reaction was judged to be phototoxic (10).

The average reaction intensity was calculated as follows: o Average reaction intensity: Jitsutsuun Ryu Toku Gunju Committee back number test results: In the table, the numbers in parentheses in the UV (1) and UV (10) sections are The number in the denominator 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.

Perfumery test The residual aroma of the natural essential oil obtained by the method of the present invention and the residual aroma of the natural essential oil (commercially available natural essential oil containing bergapten) before vacuum distillation or the distilled essential oil obtained by vacuum distillation were evaluated. The following sensory test was adopted for comparison.

15 hg of sample essential oil was evenly applied to a 5.5 x 15 scented paper and placed in a sensory testing room (temperature 25°C, humidity 60%, wind speed 0).
．． 1m/sec or less).

After an appropriate period of time (e.g., 0 minutes, 30 minutes, 1 hour, 2 hours, 4 hours) after application, a panel of 10 fragrance specialists compared the residual fragrance intensity of the sample essential oils attached to each scented paper in 10 sessions. Return and judge. Example 1 Commercially available bergamot oil with a bergapten content of 0.3% by weight1.
The crab fraction having a boiling point of 7.0 k9 was distilled under a reduced pressure of 2 Hg to obtain a colorless and transparent distilled essential oil of 960 g.

As a result of high performance liquid chromatography analysis of this crab extract essential oil, no peak of -bergapten was observed. Next, while pouring 900 g of this distilled essential oil, 110 g of 5-octyloxypsoralen and 5 g of 5-hephthyloxypsoralen were added and uniformly dissolved to obtain bergamot oil according to the present invention.

As a result of chromatographic analysis of this bergamotu oil,
The peak of bergapten also shows the peak of psoralen (psoralen,
4-methylpsoralen, 4,4-dimethylpsoralen,
The peaks of 4,5'-dimethylpsoralen, 4',8-dimethylpsoralen, 4,5',8-trimethylpsoralen, 8-methoxypsoralen, and 5-methoxypsoralen were also not observed. In addition, a light sensitivity test was conducted using the method described above for the bergamot oil according to the present invention and the commercially available bergamot oil used for vacuum distillation.

As shown in Table 2, it was confirmed that the bergamot oil according to the present invention does not have phototoxicity. Table 2 Next, the residual fragrance of bergamot oil according to the present invention (seichi of the present invention), bergamot oil before distillation (raw oil) and bergamot oil extracted from crab (crab extract essential oil) were determined by the above-mentioned fragrance residual test method. The lingering scent was compared.

As a result, as shown in Table 3, it was found that the essential oil of the present invention had the highest (strongest) residual fragrance strength and had excellent residual fragrance properties. Table 3 Note: Each value in the above table is the total number of people out of 100 people tested 10 times by 10 panelists.

Next, a sensory test was conducted regarding the smell of the essential oil of the present invention and the crab extract essential oil.

The test was performed by 10 expert examiners each with 10 repeats on each sample. The results are shown in Table 4. Table 4 Total number of people: 100 People: The essential oil of the present invention is better. 85 people: The essential oil of the invention is better. 13 people: There is no difference in superiority between the two essential oils. 2 people: In this way, the essential oil of the present invention is better in terms of odor as well. It is better than essential oils and has a pleasant aroma.

Example 2 Each of the specific psoralen derivatives (from compound-4 to compound-6) was added to the distillate essential oil obtained by distilling commercially available bergamot oil under reduced pressure under the same conditions as in Example 1. The amounts shown in Table 5 were added and uniformly dissolved to obtain bergamot oil according to the present invention.

As a result of phototoxicity testing of these bergamot oils (essential oils of the present invention), no phototoxicity was detected in any of them. Furthermore, as a result of a comparative test with the raw essential oil (commercially available bergamot oil) regarding the light aroma after the 2-hour standing time, all of the essential oils of the present invention exhibited higher residual aroma intensity than the raw essential oil. Furthermore, in the results of a comparative odor test with the distilled essential oil, the essential oil of the present invention was better in odor and superior in aroma. These results are shown in Table 5. Table 5 Note 1) In the above table, the number of people with residual fragrance strength is the total number of people (out of 100) who answered that the residual fragrance strength was higher (stronger) than the original essential oil of the control sample.

Same aircraft below. ■ The number of people who answered that it smells good is the total number of people (out of 100) who answered that the smell was better than the distilled essential oil of the control sample.

Similarly, Example 3 A mixture of the specific psoralen derivatives (from Compound-1 to Compound-6) was added to the distillate essential oil obtained by distilling commercially available bergamot oil under reduced pressure under the same conditions as in Example 1. Each blending amount (Table 6) was added and uniformly dissolved to obtain bergamot oil according to the present invention.

No optical properties of these essential oils of the present invention were detected.

Furthermore, as a result of a comparative test with the raw essential oils regarding the residual fragrance strength after 2 hours of standing time, all of the essential oils of the present invention exhibited higher residual fragrance strength than the raw essential oils. Furthermore, in the results of a comparative test on odor with the distilled essential oil, the essential oil of the present invention was better and superior in aroma.

These results are shown in Table 6. Table 6 Example 4 Orange oil (bergapten content 0.04%) (gengen essential oil) 1.0k9 was boiled at a boiling point of 70°C under reduced pressure of 2 Hg.
15 parts of 5-octyloxypsoralen was added to 900 parts of the crab extract essential oil obtained by distilling the crab fraction under reduced pressure,
Azalea, dissolved in orange oil according to the invention (essential oil of the invention)
I got it.

As a result of the phototoxicity 30 test of this orange oil, no phototoxicity was detected. Next, as a result of a comparative test with the original essential oil regarding the strength of the residual fragrance after being left for 2 hours, 89 people out of 100 felt that the essential oil of the present invention was stronger.
The number of people who felt stronger about raw essential oil was 9 out of 100.
A total of 100 people said they did not feel any difference in strength between the two.
There were two people out of all the people. , In addition, in a comparative test on odor, 8 out of 100 people said that the essential oil of the present invention was better.
Out of 8 people, 90 out of 100 people said that distillate essential oil is better, and 1 person said that there is no difference between the two.
There were 3 out of 00 people.

Claims (1)

[Claims] 1. After distilling a natural essential oil containing bergapten under reduced pressure conditions to collect a distilled essential oil that does not contain bergapten, 5-heptyloxypsoralen, 5
- A method for producing a natural essential oil with excellent aroma and no phototoxicity, which comprises blending at least one psoralen derivative selected from the group consisting of 2-ethylhexyloxypsoralen and 5-octyloxypsoralen.