JPH0429934A - Externally applicable composition containing extracted essence of ginkgo leaf - Google Patents

Abstract

PURPOSE:To obtain an externally applicable composition having low irritation and high absorptivity by mixing extracted an essence of ginkgo leaf and cutaneous absorption accelerator. CONSTITUTION:The objective composition contains an extracted essence of ginkgo leaf and a cutaneous absorption accelerator, e.g. a urea derivative, hyalurons, salicylic acids, a terpene or a glyceride of fatty acid with middle chain length in a weight ratio of the former: the latter=1:(0.1-10). Said essence is preferably contains >=15% flavonoid or glycoside of said flavonoid if the pharmaceutical and beautifying effects of the extracted essence of ginkgo leaf is to be exhibited and especially an essence containing 24% flavonoids is the most preferable one from the viewpoints of both reducing skin irritation by the cutaneous absorption accelerator and the pharmaceutical/beautifying effects. A drug component or beautifying component, etc., other than essence of ginkgo leaf can simultaneously be added to the externally applying composition, according to the purpose.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a composition for external use that is applied to the external surface of the body, such as the skin, and particularly relates to a low irritation and highly absorbent external preparation containing ginkgo leaf extract. .

[Prior art and invention or problem to be solved] Conventionally,
BACKGROUND ART One method for introducing active ingredients of pharmaceuticals and cosmetics into the human body is to apply external preparations containing the active ingredients to the skin, thereby introducing them into the body through the skin.

However, since the skin originally acts as a barrier to prevent the infiltration of exogenous substances, many active ingredients added to external preparations are hardly absorbed as they are and cannot fully exert their intended effects. There wasn't.

Therefore, it is necessary to increase the amount of percutaneous absorption of active ingredients,
Recently, the addition of transdermal absorption-promoting substances to formulations has been considered.

Transdermal poultices and gels containing absorption-promoting substances have already begun to be put into practical use as non-steroidal analgesic and anti-inflammatory drugs.

It is of great significance that transdermal absorption of the active ingredient is made possible in this way.

However, on the other hand, when applying transdermal topical preparations,
Problems such as skin rashes, rashes, and itching occur. This is due to the irritating properties of transdermal absorbents.

Most transdermal absorption enhancers have a mechanism of action that causes some kind of change in the stratum corneum, such as extracting lipids and riboproteins from the stratum corneum, which is the barrier layer of the skin.

These transdermal absorption enhancers include not only those with strong skin irritation such as DMSO (dimethyl sulfoxide) and ionic surfactants, but also other substances that forcefully absorb active ingredients that are difficult to absorb. Considering its purpose of stimulating skin irritation, it is more or less irritating to the skin.

By the way, transdermal absorption preparations, in which a transdermal absorption enhancer is added to make it easier for the active ingredient to be absorbed through the skin, are easier to control the absorption of the active ingredient than oral preparations, and the active ingredient is not easily absorbed by the liver. It has many advantages such as not being metabolized and having little user resistance. However, as mentioned above, transdermal absorption enhancers have some degree of skin irritation, which is problematic especially when used for a long period of time.

On the other hand, ginkgo leaf extract has the effect of improving blood flow and is mainly used orally for cardiovascular diseases, but it has the disadvantage that it is difficult to be absorbed through the skin.

[Means for Solving the Problems] As a result of intensive research, the present inventors have found that by adding ginkgo leaf extract and a transdermal absorption agent to a composition for external use, the irritation caused by the transdermal absorption enhancer can be significantly reduced. In addition, we have discovered that the active ingredients (such as ginkgolide and flavonoids) in ginkgo leaf extract can be absorbed transdermally with high efficiency.

The present invention has been made based on this new knowledge, namely, the present invention is an external composition characterized by containing a ginkgo leaf extract and a transdermal absorption enhancer.

In the external preparation of the present invention, the content ratio (weight ratio) of the ginkgo leaf extract to the transdermal absorption enhancer is preferably 0.1 to 10, and the ginkgo leaf extract contains:
Ginkgo leaf extract contains 15 flavonoids and their glycosides.
% or more is preferred.

In addition to the above findings, the present inventors have also discovered that irritation caused by adhesives used in patches and poultices and deterioration of adhesiveness due to oxidation of the adhesive itself can be prevented. In addition, ginkgo leaf extract has medicinal and beauty effects such as the treatment of chilblains, chapping, and burns due to its blood circulation promoting effect and antioxidant effect, reducing the appearance of dark spots and freckles due to sunburn, and its water-retaining effect. It has been found that these can be obtained at the same time by using an accelerator in combination.

To obtain ginkgo leaf extract, first, green leaves before yellowing are extracted with a solvent such as boiling water, aqueous ethanol, or aqueous methyl ethyl ketone, and then the extracted solution is heated to remove the solvent and the residue is extracted. A solid ginkgo leaf extract is obtained. In addition, if necessary, it can be purified by column chromatography or the like to increase the purity.

The obtained extract contains flavonoids such as quercetin and kaempferol and their glycosides (hereinafter referred to as flavonoids), as well as ginkgolide (a type of terpene lactone), a special component contained in ginkgo leaves.

According to the research conducted by the present inventor, the content ratio (weight ratio) of ginkgo leaf extract to the transdermal absorption enhancer should be 1.0.1 to 10 in order to reduce skin irritation caused by the transdermal absorption enhancer. preferable. If the amount of transdermal absorption enhancer is less than 01, pharmaceuticals,
The absorption of active ingredients such as ginkgo leaf extract in the body is not promoted, and if the number exceeds 10, the absorption of the active ingredients in the body is promoted, but the skin irritation is strong and the skin becomes irritated or itchy. do.

When trying to obtain both the medicinal and cosmetic effects of the ginkgo leaf extract, it is preferable that the ginkgo leaf extract contains at least 15% flavonoids, and especially one containing 24% flavonoids. , is the most preferable from the viewpoint of reducing skin irritation caused by the transdermal absorption enhancer and also from the viewpoint of medicinal efficacy and cosmetic effect. When a ginkgo leaf extract with a flavonoid content of less than 15% is incorporated into a composition for external use, the color becomes strong brown, the appearance is poor, and the commercial value decreases.

Transdermal absorption enhancers include urea derivatives, hyaluronans, pyrrolidones, salicylic acids, DMF, DMSO, ionic surfactants, nonionic surfactants, terpenes,
There are terpene alcohols, terpene compounds, other medium-chain fatty acid glycerin esters, polyglycerin fatty acid esters, lecithin, oleic acid, etc., and active substances that achieve medicinal and beauty effects, which are absorption target substances, and ginkgo leaf extract, etc. A substance that promotes skin absorption.

External compositions containing ginkgo leaf extract and transdermal absorption enhancers include many external preparations applied to the skin, hair, mucous membranes, etc., such as liquid spray lotions, ointments, creams, gels, sol, aerosols, and poultices. Refers to agents, plasters, tapes, etc. In the present invention, medicinal ingredients or cosmetic ingredients other than the ginkgo leaf extract may be added at the same time depending on the purpose.

[Example] Hereinafter, the present invention will be explained in detail with reference to some examples.

Example 1: A skin irritation test was conducted on external preparations containing ginkgo leaf extract and transdermal absorption enhancers, and other external preparations.

Hydrated Soybean Lecithin (NIKKOL Resinol S)
-10)...25 g Tocopherol acetate...0.2 g Hitamine A palmitate...0.1 g Liquid paraffin #350...747 g were mixed well on a hot water bath to prepare an oil-based gel. Prescription (A) was used.

To this basic formulation (A) Log, 8 g of dimethyl sulfoxide (DMSO) and 2 g of ethanol were mixed to obtain a comparative formulation (B).

This comparative formulation (B) contains 1 g of each flavonoids.
．． Three types of ginkgo leaf extracts of 8%, 9.2%, and 19.8% were added and mixed in an amount of 50 mg each to prepare Invention Prescription 1, Invention Prescription 2, and Invention Prescription 3.

Local irritation test Using Torii Patch Kizuna (Small size), the above external preparation 0
, 1g of all types, 48% on the normal skin of the backs of 5 men
The patch was applied for a period of time, and the degree of skin reaction was compared between 1 and 24 hours after the patch was removed.

Judgment criteria are as specified in Table 1.

The results are shown in Table 2 by taking the average value of 5 people.

As a result of the test, as shown in Table 2, the topical preparation (B) to which only the transdermal absorption enhancer was added clearly caused a skin irritation reaction, but the ginkgo leaf extract of the example of the present invention was also added. It was found that all of the external preparations caused significantly less skin irritation.

Thus, it was found that the irritation-reducing effect of ginkgo leaf extract is remarkable. It should be noted that irritation-reducing effects were also observed in those with low flaphonite content.

Example 2: Effect on redness and cracking Using the formulations 1 and 3 of the present invention prepared in Example 1, the formulation 1 of the present invention was applied to the left hands of two women who had cracked fingertips in winter.
Right hand I＼Prescription 3 of the present invention 4 to 5 times a day on both hands at the same time every day
The conditions of rubbing were compared.

As a result, the pain in both women's right hands disappeared and the cracks closed from around the 1st day after applying Formula 3 of the present invention, which contains ginkgo leaf extract with a high content of flavonoids (19.8%). The severe cracking disappeared around the 14th day.

- The left hands of the two women who rubbed the present invention formulation 1, which contains ginkgo leaf extract with a low content of gaflavonoids (1.8%), showed some therapeutic effect, but the cracks remained as they were. Met.

Example 3: Production of emollient cream ■Hydrogenated soybean lecithin (NIKKOL Resinol S~10)...20g Qg...4g...0.5g 0.15g...355.35°...25g... 5g ...5g 5g Surfactant NIKKOL Trifat S-308
Methyl nonononopropyl paraoxybenzoate stearate Purified water ■ Glycerin-reduced starch hydrolyzate (70% aqueous solution) Sodium dl-pyridocycarboxylate (5 oz aqueous solution) Purified water After preparing the above ■ and ■ separately, mix both well. An emollient cream was prepared. This was designated as basic prescription (C).

A comparative formulation was prepared by adding ginkgo leaf extract (containing 243% flavonoids) Ig to this basic formulation (C)] and OOg and mixing well.

Separately, using 100 g of the basic formulation, add ginkgo leaf extract (containing 24.3% flavonoids) Ig as in the comparative formulation (D), and further add 3 g of propylene glycol and 3 g of 1-carvone as transdermal absorption enhancers. Invention formulation 4 was prepared by mixing.

18 women concerned about beauty were divided into 3 groups: the basic prescription (C) group, the comparison prescription (D) group, and the 4 groups of the invention prescriptions, and the results were evaluated after using each product for 201 times. compared.

Five items were compared: skin appearance, firmness, smoothness, soft feel, and freshness.
It was conducted in three stages: valid and invalid. The results are shown in Table 3.

Table 2. Evaluation after use for 20 days As is clear from the results in Table 3, adding ginkgo leaf extract alone is not much different from adding no ginkgo leaf extract at all, but adding transdermal absorption enhancer in combination A clear improvement in the cosmetic effect was observed with this prescription.

[Effects of the Invention] As described above, when the external composition of the present invention is used, the skin irritation caused by the transdermal absorption enhancer can be significantly reduced.

As a result, active ingredients such as medicines and beauty ingredients can be taken into the body without causing rashes, itching, etc. due to skin irritation.

At the same time, ginkgo leaf extract can be absorbed into the body with high efficiency.

Claims (3)

[Claims] (1) A composition for external use comprising a ginkgo leaf extract and a transdermal absorption enhancer. (2) The composition for external use according to claim 1, wherein the content ratio (weight ratio) of ginkgo leaf extract to transdermal absorption enhancer is 1:0.1 to 10. (3) The composition for external use according to claim 1 or 2, wherein the ginkgo leaf extract contains 15% or more of flavonoids and their glycosides.