IE67165B1 - New cosmetic compositions containing plant extracts - Google Patents

Abstract

Cosmetic compositions for the treatment and care of the skin are prepared by mixing an extract obtained from Kalamet or Taung-taunggi wood with suitable excipients or diluents. Kalamet (Mansonia gagei) and Taung-taunggi (Premna integrifolia) are Burmese plants and the extracts which are obtained from the wood of these plants have collagenase-inhibiting properties as well as antiradical and hyaluronidase-inhibiting properties.

Description

NEW COSMETIC COMPOSITIONS CONTAINING PLANT EXTRACTS The present invention concerns cosmetic compositions for skin care and treatment containing oriental plant extracts and more particularly Burma plant extracts.

The odoriferous properties of some Burma woods and particularly of Thanat-Kha and Kalamet woods are well known.

It is also known that in Burma and Thailand the wood of naturally dead trees be employed as cosmetics : traditionally they are prepared by crushing the bark or the wood on moistened marble and mixing the thus obtained substance with a small amount of water before applying it directly onto the skin.

Cosmetic products for skin care containing powders or extracts of Thanat-Kha are described in Japanese patent application JP §3-65209.

It is also known that extraction of Premna integrifolia leaves may afford lutenlin (Chemical Abstracts, 1985, 102, n' 163722s), a flavonoid which can be extracted from a great number of different plants, whose depigmenting properties have been described in FR-A-2,578,422.

It has now been found that, starting from Kalamet (Mansonia. gaeei) or Taungtaunggi (Premna integrifolia) woods, extracts may be obtained which possess very important and quite specific cosmetic properties and are well suited to the preparation of cosmetic compositions for skin care.

More particularly it has been found that starting from these woods extracts can be obtained,which show collagenase and hyaiuronidase inhibiting properties.

It has also been found that extracts obtained from Kalamet or Taung-taunggi have free radical scavenging properties and increase tyrosinase activity.

These last properties are particularly surprising because they seem to be specific to the Kalamet and Taung-taunggi extracts. As an example, Thanat-kha extracts are inactive as free radical scavengers and do not increase tyrosinase activity.

Kalamet (Mansonia gagei) is a tree belonging to the family Sterculiaceae, found in South Tenasserim in Myanmar by F.B. Manson. It grows to 12 m in height and about 1 m in girth, its distribution is extremely local and it is practically confined to the drainases of the Sarawa and Kalamet streams.

Taung-taunggi (Premna integrifolia) is a shrub belonging to the family Verbenaceae distributed on the sea-shore in Tenasserim. It is characterised by a fairly hard, creamybrown wood.

For the preparation of the extracts, the whole Kalamet or Taung-taunggi wood or the internal pan thereof is cut up in very small pieces, or even pulverised. Then the substrate is treated with a suitably selected extraction solvent or solvent mixture, after a few hours the mixture is filtered and the thus obtained solution is evaporated to dryness. Ί Ζ" If desired, the extraction procedure is repeated, starting from the thus obtained residue, with the same or a different extraction solvent or solvent mixture.

The organic solvents which may advantageously be employed, alone or in admixture, are lower alkanols, such as methanol, ethanol, and isopropanol, glycols such as ethylene glycol, and propylene glycol, mono-ether derivatives thereof such as 2methoxyethanol and 2-ethoxyethanol, ethers such as ethyl ether, isopropyl ether, or dimethoxyethane, halogenated aliphatic hydrocarbons such as chloroform, methylene chloride, and 1,1,1-trichloroethane, ketones such as acetone, aromatic hydrocarbons such as toluene, etc..

These solvents or solvent mixtures may also contain some water, in different proportions depending on their miscibility with water.

Particularly advantageous solvents or solvent mixtures are lower alkanols, such as methanol and ethanol, mixtures of a lower alkanol, such as methanol or ethanol, or of a lower glycol, such as ethylene glycol or propylene glycol, with water in a ratio comprised between 30/70 and 70/30 by volume; other preferred mixtures are those of a lower alkanol or glycol, as defined above, with a halogenated aliphatic hydrocarbon such as chloroform, methylene chloride, or 1,1,1-trichloroethane, in different proportions depending on their respective miscibilities.

As for the ratio between the volume of the substrate and the volume of the extraction solvent or solvent mixture (extraction solvent) to be employed, it is generally comprised between 1/3 and 1/20, and preferably between 1/7 and 1/15. Larger volumes of the extraction solvent might be employed but the increase in the production costs will not be compensated by a corresponding increment of the extraction yields.

After a few hours, generally from 8 to 16 hours, the mixture is filtered at room temperature and the solvents are evaporated off under vacuum to afford a residue. Said residue, as indicated above, may undergo another extraction followed by under vacuum evaporation of the solvent or solvent mixture.

If extraction solvents are employed which are, even in trace amounts, toxic or unsuitable for a cosmetic use, the obtained extracts may be purified by treatment with a small amount of methanol or ethanol followed by evaporation of this last solvent. Said treatment may optionally be repeated.

As an example, according to the present invention, extracts are easily obtained by the above indicated general procedure using a lower alkanol such as methanol or ethanol, or a mixture methanol/water 50/50 (v/v) or a mixture methanol/methylene chloride 50/50 (v/v) as the extraction solvent, and a substrate/solvent ratio of 1/10, allowing the extraction to proceed for 12 hours, then removing the insoluble by filtration at room temperature and evaporating off the solvent under reduced pressure (10 mmHg corresponding to 1300 Pa). The thus obtained extract may then undergo another extraction according to the general indications given above.

The activities of the thus obtained extracts have been evaluated by methodologies derived from the classical techniques which are conventionally employed in biochemistry and are now becoming well known and widely employed also in cosmetology.

More particularly these extracts have been submitted to the collagenase inhibition test, the free radical scavenging test, the tyrosinase activation test, and the hyaluronidase inhibition test.

In the first of the above tests, the extracts of the present invention have shown a remarkable inhibitory activity of collagenase, a proteolytic enzyme which entails degradation of collagene, one of the two main skin structural proteins, whose role in the maintenance of skin integrity, mainly in the skin aging process, is fundamental.

The extracts of the invention also shown to be active as free radical scavengers.

The free radicals which are generated at skin level by the different environmental physical and chemical aggressive agents, and mainly by U.V. radiations, are very dangerous (B.Halliwell and J.M.C. Gutteridge - Free radicals in biology and medicine Oxford : Clarendon Press; 1985 : 346). Free radicals in fact oxidize cell membrane lipids, destroy structural proteins, deregulate enzymes and might also modify the genetic code. The extracts of the invention which are very active in scavenging the free radicals as ±ey form, may therefore be conveniently employed in a cosmetic composition to attenuate the deleterious effects of the aggressive agents, mainly the sun (erythema, premature aging, etc.), to skin.

Some extracts of the present invention also activate tyrosinase, an enzyme which plays a fundamental role in the biosynthesis of eumelanines from tyrosine and may therefore be employed in a cosmetic composition to facilitate tanning.

The use of the extracts of the present invention in the cosmetic field for slowing down or treating skin aging and tissue degenerescence and for improving tanning is therefore a further specific object of the present invention. For the use for improving tanning, the free radical scavenging properties of the extracts are extremely useful as sunlight faciliates formation of free radicals.

For cosmetic use, the extracts according to the present invention may be formulated as creams, gels, lotions, emulsions, solutions, ointments, etc., containing from 0.001 to 10 % and preferably from 0.005 to 5 % by weight of said extracts. When starting from Taung-taunggi wood the cosmetic compositions of the invention will generally contain less than 0.1 % and preferably less than 0.05 %;in particular from 0.005 to 0.02 % of the extract, because of the colour given by the extract to the finished product.

For the preparation of cosmetic compositions, the extracts are admixed with the 5 excipients conventionally employed in the cosmetic field, such as animal fats, vegetable oils, saturated or unsaturated fatty acids, alcohols, esters of fatty acids with fatty alcohols, polyalkylene glycols, waxes, vaseline, polyethers, and the like and may be used in association with water and jelling agents provided they are compatible therewith.

For a better use of the extracts of the invention in the preparation of cosmetic compositions, said extracts are admixed to the excipients and additives, as solution in a solvent or mixture of solvents suitable for the desired cosmetic application. As an example, these extracts may be employed as solutions in glycol/water mixtures depending on the solubility of the extract itself.

The cosmetic composition of the present invention can be in the form of a cream wherein the extract is associated with the excipients which are commonly employed in cosmetology and which are compatible therewith, such as lanolin and its derivatives.

The cosmetic composition of the present invention may also be in the form of a gel in a suitable vehicle such as a cellulose ester or other jelling agents such as carbopol, guar gum, etc..

The cosmetic composition according to the present invention may also be in the form of a lotion or solution wherein the extract is dissolved or microdispersed in a microemulsion.

The cosmetic composition of the present invention can therefore be in the form of a 25 microdispersion of the extract in a fluid containing water and one or more surfactants. These dispersions have the same properties as microemulsions and the same appearance as true solutions. They are preferably prepared immediately before use.

These microemulsions possess a good stability and can be stored for the time necessary for their use, at temperatures from 0 to 60°C without sedimentation of the constituents or irreversible phase separation.

The surfactants used in the composition are selected among those which can suitably be employed in cosmetology. As non limitative examples of suitable surfactants there may be cited : sorbitol esters and their polyethoxylated derivatives, polvethoxylated (hydrogenated or non hydrogenated) castor oils, ethylene oxide/propylene oxide block polymers, polyethoxylated fatty acids, polyethoxylated fatty alcohols, sodium laurylsulfate, sodium dioctylsulfosuccinate, egg or soya lecithins. Γ The cosmetic composition of the present invention may also contain suitable additives or adjuvants as usual in cosmetology such as antibacterial agents or fragrances.

The cosmetic composition of the present invention may also contain other 5 complementary active principles selected on the basis of their action on e.g. cellular nutrition, cellular respiration, hydration and cellular regeneration, as well as other active principles with the same type of skin protecting activity.

When the cosmetic composition of the present invention contains complementary active agents they are generally contained in the composition in a concentration sufficiently high to provide the desired complementary activity.

Complementary active principles are for instance hydrating agents such as hyaluronic acid, or pyrrolidincarboxylic acid sodium salt, protecting agents such as panthenol, a protecting vitamin substance, cellular growth factors such as bovine spleen extracts or yeast extracts, etc..

The cosmetic composition of the present invention should preferably be applied every day, once or more times a day depending on skin conditions.

The cosmetic compositions of the present invention are generally well tolerated; they have no phototoxicity and their application to ±e skin for prolonged periods of time does not give rise to any systemic effects. Generally, by applying the cosmetic compositions of the present invention for 30 days, a notable improvement in skin appearance and a slowing down of wrinkle formation can be achieved.

The cosmetic compositions of the present invention may also be formulated as makeup products, such as for instance foundations, face powders, eye shadows, or lipsticks.

Foundations are solution or lotion-based and contain an extract of the present 25 invention with appropriate amounts of thickeners, pigments and fragrances.

The face powders, as well as the eye shadows, can be obtained according to the conventional methods, by mixing an extract according to the invention with a powder or eye shadow base which generally contains talc, carbonates, oxides, suitable proportions of fragrance and pigments, preferably organic, and optionally binding agents.

For the orenaration of lipsticks the extrarr ic mixed with an oil-wax base stiff enough to form a stick, with pigmentation dispersed therein.

The following examples further illustrate the invention without limiting it.

EXAMPLE ϊ Kalamet wood is cut in pieces which are treated with a methanol/water 50/50 mixture (10 ml of solvent mixture per gram of cut wood). After 12 hours at room temperature, the mixture is filtered and the filtrate is evaporated off under reduced pressure (about 1300 Pa) to get a pasty residue. Said residue is taken up with methanol (2 ml). The thus obtained solution is submitted to the above indicated cosmetic tests and shows collagenase inhibiting activity, free radical scavenging activity, and hyaluronidase inhibiting activity.

EXAMPLE 2 By following the procedure described in Example 1 but using 95 % ethanol as the extracting solvent, starting from 250 g of cut wood a dry extract (3.1 g) is obtained which dissolved in methanol, shows collagenase inhibiting activity, free radical scavenging activity and hyaluronidase inhibiting activity.

EXAMPLE 3 By following the procedure described in Example 1 but using a mixture methanol/methylene chloride 50/50 (v/v) as the extracting solvent, an extract is obtained which, dissolved in methanol, shows very interesting free radical scavenging and collagenase inhibiting activities.

EXAMPLE 4 By following the procedure of Example 1 but starting from Kalamet powder obtained by pulverization of the raw wood, an extract is obtained which shows collagenase inhibiting and free radical scavenging activities as the extract of Example 1 and also tyrosinase stimulating properties.

EXAMPLE 5 By following the procedure of Example 3 but starting from the Kalamet powder employed in Example 4 an extract is obtained which shows the same activities as the extract obtained in Example 3.

EXAMPLE 6 By operating as described in Example 1 but starting from pulverized Taung-taunggi wood, an extract is obtained which is very active as collagenase inhibitor, free radical scavenger and tyrosinase activator.

EXAMPLE 7 Starting from pulverized Taung-taunggi wood and operating as described in Example 3, an extract is obtained which shows the same activities as the extract obtained in Example 6.

EXAMPLE 8 Starting from a Taung-taunggi powder obtained by pulverization of the raw wood, using the extraction procedure described in Example 2 and evaporating off methanol, an extract is obtained which shows the same properties as the extract obtained in Example 6.

EXAMPLES 9 - Ig The following compositions are prepared for the use indicated in each example. examples Moisturizing gel Extract of Example 1 0.50 g Carbopol 940 0.20 g Polyethylene glycol 3.00 g Preservatives 0.50 g Butylene glycol 5.00 g Ethoxylated sorbitan laurate 0.50 g Fragrance 0.20 g Triethanolamine 0.25 g Demineralised water Q.S.F. EXAMPLE 10 Night cream 100 g Extract of Example 4 1.00 g Cetyl alcohol 2.00 g Stearin 2.50 g Glycerol monostearate 5.00 g Isopropyl palmitate 5.00 g Vegetable oil 3.00 g Mineral oil 2-00 g Perhydrosqualene 2.00 g Silicon oil 1.00 g Shea butter 2.00 g 2-Ethyl-hexyl palmitate 5.00 g Triethanolamine 5-50 g Preservatives 0.50 g Butylene glycol 5.00 g Tetrasodium EDTA 0.30 g Fragrance 0.31 g Antioxidant 0.10 g Demineralised water Q. S. F. 100 g EXAMPLE Π Moisturizing serum Extract of Example 8 0.01 g Hydroxypropylmethylcellulose 0.30 g Propylene glycol 5.00 g Glycerol 5.00 g Ethoxylated oleic alcohol 0.50 g Fragrance 0.30 g Tetrasodium EDTA 0.10 g Preservatives 0.50 g Bovine albumin 5.00 g Demineralised water Q. S. F. 100 g EXAMPLE.12 Fluid make-up base Extract of Example 8 0.005 g Ethoxylated soja sterols 4.00 g Soja sterols 0.50 g Glycerol monostearate 1.00 g Vegetable oil 1.50 g 2-Ethyl-hexyl palmitate 4.00 g Cetyl alcohol 0.50 g Capric/caprylic triglycerides 1.50 g Silicon oil 1.00 g Mineral oil 1.80 g Lanolin alcohols 0.20 g Propylene glycol dipelargonate 3.00 g Lecithin 1.00 g Preservatives 0.50 g Butylene glycol 5.00 g Carbopol 0.20 g Triethanolamine 0.20 g Tetrasodium EDTA 0.10 g Antioxidant 0.01 g Fragrance 0.30 g Demineralised water Q„S„F. 100 g EXAMPLE 13 Protective day cream Extract of Example 6 0.02 g Ethoxylated sorbitan monostearate 2.60 g Silicon oil 1.00 g Cetyl alcohol 2.00 g Mineral oil 3.00 g Lanolin alcohols 1.00 g Perhydrosqualene 1.00 g Sorbitan monostearate 2.40 g Cetyl palmitate 3.00 g Isopropyl palmitate 4.00 g UVA - UVB filters 2.00 g Tetrasodium EDTA 0.10 g Carbopol 0.30 g Triethanolamine 0.30 g Antioxidant 0.01 g Preservatives 0.50 g Fragrance 0.30 g Butylene glycol 5.00 g Demineralised water Q. S. F. 100 g EXAMPLE 14 Moisturizing microemulsions Extract of Example 3 0.10 g Polyethylene glycol 600 hydroxystearate 1.00 g Polyoxyethylene Cy-Cg triglycerides 0.25 g Polyethylene glycol-7 glyceryl cocoate 0.20 g Dimethicone copolyol 0.05 g Propylene glycol 12.50 g Ethanol 12.50 g Carbopol 0.40 g Triethanolamine 0.40 g Fragrance 0.30 g Pigments Q.S.

Preservatives 0.50 g Demineralised water Q.S.F. 100 g EXAMPLE 1$ Extract of Example 2 Moisturizing foundation 5.00 g Tetrasodium EDTA 0.10 g Carboxymethylcellulose 0.20 g Ethoxylated sorbitan laurate L00g Propylene glycol 5.00 g Titanium Oxide 2.00 g Talc LOO g Pigments 1-00 g Triethanolamine 0.50 g Preservatives 0.50 g Cetyl alcohol 1-00 g Lanolin alcohols 3.00 g Stearic acid 1.80 g Propylene glycol monostearate 3.00 g Isopropyl palmitate 8.00 g Vegetable oil 2.00 g Antioxidant 0.05 g Fragrance - 0.30 g Demineralised water Q.S.F. 100 g

Claims (5)

1. A cosmetic composition for skin care and treatment, characterised in that it comprises an extract obtained from Kalamet (Mansonia gagei) or Taung-taunggi (Premna integrifolia) wood in admixture with a cosmetically and dermatologically acceptable excipient or diluent.

2. The cosmetic composition of claim 1, characterised in that it comprises between 0.001 and 10% by weight of Kalamet or Taung-taunggi wood extract.

3. The cosmetic composition of claim 2, characterised in that it comprises between 0.005 and 5% by weight of Kalamet or Taung-taunggi wood extract.

4. The cosmetic composition of claim 3, characterised in that it comprises between 0.005 and 0.02% by weight of Taung-taunggi wood extract. 5. The cosmetic composition of any one of the preceding claims 1 to 4, characterised in that the Kalamet or Taung-taunggi extract is obtained from the whole wood or the internal part thereof by extraction with a suitable extraction solvent, filtration and dry-evaporation of the filtrate, this extraction process being optionally repeated on the extract thus obtained. 6. The cosmetic composition of claim 5, characterised in that the extraction solvent is selected among the lower alkanols, lower glycols, glycol monoethers, alkyl ethers, halogenated aliphatic hydrocarbons, ketones, aromatic hydrocarbons and mixtures thereof, optionally containing varying proportions of water. 7. The cosmetic composition of claim 6, characterised in that the extraction solvent is selected among the methanol, ethanol, methanol/water mixtures, and methanol/methylene chloride mixtures. 8. Use of the composition of any one of claims 1 to 7 for slowing down or treating skin ageing and tissue degenerescence and to facilitate suntanning. 9. Method for preparing a cosmetic composition according to any one of claims 1 to 7, characterised in that it consists in mixing an extract obtained from Kalamet (Mansonia gagei) or Taung-taunggi (Premna integrifolia) wood in admixture with a cosmetically and dermatologically acceptable excipient or diluent. 12 10. A cosmetic composition according to claim 1, substantially as herein described in the Examples. 11. The use according to claim 8. substantially as herein described.

5. 12. A method for preparing a cosmetic composition according to claim 9, substantially as herein described.