FR2779646A1 - PLANT EXTRACT OF CEREALS BASED ON POLAR LIPIDS AND COSMETIC COMPOSITION COMPRISING SUCH A PLANT EXTRACT - Google Patents

Abstract

The invention concerns a cereal plant extract based on polar lipids comprising a mixture of phytosphingolipids and phyto-glycoglycerolipids in a weight ratio ranging between 0.5 and 2. Said plant extract has remarkable anti-collagenase and anti-elastase properties. The invention also a cosmetic composition comprising said plant extract, in particular in the form of an autoemulsive cosmetic composition. The invention further concerns the preparation of vegetable oils obtained from the extraction and purification method for use in cosmetic and dietetic formulations.

Description

I The subject of the present invention is a new plant extract based on

  polar lipids useful in the cosmetic field, in particular for

  face and body care or for hair care.

  It also relates to an emulsifiable composition comprising such a plant extract, useful in the cosmetic or pharmaceutical field. It also relates to a process for obtaining such a plant extract. The cutaneous tissue is an organ participating in the maintenance of the homeostasis of the individual. Indeed, the skin has water retention properties. These properties are due, among other things, to the presence of

  lipids, organized in a multilamellar network within the stratum corneum.

  In addition to the water retention capacity, these lipids ensure the cohesion of the epidermis by establishing links between the corneocytes,

  thus contributing to the suppleness and flexibility of the skin.

  The lipids playing a primordial role in the epidermis are the sphingolipids and the glycosphingolipids (also called ceramides and

  glycosylceramides or cerebrosides).

  During skin aging (physiological or photoinduced) or during skin pathologies (psoriasis, atopic dermatitis), a lipid imbalance appears, leading to skin dehydration and

loss of skin suppleness.

  Skin aging is also linked to increases

  secretion and activity of different enzymes including collagenase.

  This metalloproteinase has preferential substrate fibrillar collagens and glycosaminoglycans. The increase in collagenase activity therefore results in an increase in the degradation of collagen fibers, which partly explains the loss of resistance of the collagenase.

  skin tissue that appears with age.

  In the same way, the increase in the activity of collagenase leads to a significant degradation of the glycosaminoglycans, macromolecules widely involved in maintaining the hydration of the dermis. We can indeed establish a correlation between the decrease in the amount of glycosaminoglycans and the decrease in the water content of

  skin tissue that appears with age.

  The inflammatory process that develops in the body (UV exposure, burns, inflammatory skin conditions, rheumatoid arthritis, periodontal disease, pulmonary emphysema) is a very complex phenomenon. It is the result of close interactions between matrix components, inflammation cells and proteolytic enzymes. Among these enzymes, human leukocyte elastase is widely involved in tissue damage linked to the inflammatory phenomenon. The spectrum of action of this serine protease is very wide (collagens, fibronectin, proteoglycans, inhibitor of matrix metalloproteinases, hemostasis factors, coagulation factors, immunoglobulins ...). In the case of chronic inflammation, elastase leads to an amplification of the inflammatory reaction and leads to alterations of the connective tissue which is sometimes irreversible. Currently, the cosmetic and pharmaceutical industry is always looking for new compounds or active principles, in particular products of plant origin to limit, or even prevent, these alterations which appear during aging or else during inflammatory phenomena. The development of products of plant origin making it possible to replace compounds of animal origin is essential in order to be able to place on the market in cosmetics, dietetics or pharmacy, products substituting for products of animal origin thus avoiding the risk of viral contamination by prion type viruses. These viruses, such as the mad cow virus, develop in the nervous system of ruminants and is currently recognized as transmissible to humans, causing

Creutzfeldt-Jakob disease.

  The main applications of the cosmetic or pharmaceutical composition according to the invention are: anti-aging action on the skin, anti-inflammatory action, stabilization and protection of

  active ingredients in said compositions.

  An object of the present invention is in particular to propose a new plant extract which has a beneficial effect with regard to the hydrating power, the maintenance of the integrity of the intercorneocytic cement and

the suppleness of the skin.

  Another object of the present invention is to provide a new plant extract exhibiting anticollagenase activity (TIMP-1) for

  concentrations equal to or greater than 5 gg / ml.

  Another object of the present invention is to propose a new plant extract having an anti-elastase human leukocyte activity (enzymatic test applied according to the method described by Nakajima and collaborators in 1979: Nakajima K., Powers JC, Ashe B., Zimmerman MJ , (1979). Mapping the extended substrate binding site of cathepsin G

  and human leukocyte elastase. J. Biol Chem 254: p. 4027-4032).

  The concentration which inhibits 50% of the elastase activity is equal to

about 55 gig / ml.

  The solution to the abovementioned technical problems is obtained by a plant extract of cereals based on polar lipids, characterized in that it comprises a combination of phytosphingolipids and

  phytoglycoglycerolipids in a weight ratio between 0.5 and 2.

  It has indeed been found that the association of the two families of compounds mentioned above in the above-mentioned report exhibits the remarkable properties

set out above.

  The cereals which can be used to obtain the extract according to the invention are generally all the known cereals which can be

  cite particularly wheat, barley, rye, oats, corn, sorghum.

  The polar lipids which constitute the extract according to the invention come from lipids called "bound lipids" because they are associated with the protein fraction of cereals; in wheat for example, the protein mass contains 5 to 10% of bound lipids according to the varieties of wheat. Most of the bound lipids are in the form of lipid vesicles with a diameter of less than 300 nm, inserted into the protein network; a small proportion of bound lipids is "adsorbed" on the surface of the protein network. These bound lipids are composed of 70% polar lipids, hence the advantage of working with this fraction of cereals, in order to purify the phytoglycoglycerolipids and phytosphingolipids. Phytosphingolipids can exist in glycosylated form; they

  are called glycosylceramides or cerebrosides.

  Phytoglycoglycerolipids include in particular the

  glycosyldiglycerides such as digalactosyldiglycerides.

  According to a preferred variant, the weight ratio between the phytosphingolipids and the phytoglycoglycerolipids is between 1 and 1.8. According to another variant, the plant extract comprises at least 70% of phytosphingolipids (in glycosylated form or not) and of

phytoglycoglycerolipids.

  As the exact composition of the extract according to the invention is a function of the nature of the cereal and of the extraction process, said plant extract may comprise, according to a variant, triglycerides and / or phospholipids. According to a first variant, the vegetable extract in oily form comprises in percentage by weight: - Phytosphingolipids and 10 to 20% Glycosphingolipids - Phytoglycoglycerolipids 10 to 20% (including digalactosyldiglycerides) - Triglycerides 50 to 65% - Phospholipids 10 to 15% According to the second variant the plant extract in the form of a polar lipid powder comprises in percentage by weight: - Phytosphingolipids and 45 to 55% Glycosphingolipids - Phytoglycoglycerolipids 30 to 40% (including digalactosyldiglycerides) - Triglycerides 0 to 5% - Phospholipids 10 to 20% According to a third variant, the vegetable extract in oily form comprises in percentage by weight: - Phytosphingolipids and 4 to 9% Glycosphingolipids - Phytoglycoglycerolipids 5 to 10% (including digalactosyldiglycerides) - Triglycerides 75 to 85% - Phospholipids 1 to 6% The properties of hydration by incorporation of the oil according to the first variant in creams or ointments t especially linked to the content of glycosphingolipids, sphingolipids and digalactosyldiglycerides which have great water retention capacities. In addition, the presence of triglycerides limits water losses

  on the surface of the epidermis.

  The incorporation of the oil according to the first or third variant in nutritional supplements also gives very good

  results concerning skin hydration.

  Triglycerides are non-polar lipids and the plant extract containing them especially the oil according to the third variant can therefore serve as a support for the incorporation of vitamins or other liposoluble compounds such as vitamin A, vitamin E, carotenoids for

  topical or oral applications.

  As mentioned above, the combination of phytosphingolipids, glycosphingolipids and phytoglycoglycerolipids according to the second variant reveals not only interesting biochemical and physiological properties but also very great ease of use in formulation for the

  production of the finished product (cosmetic, dietetic or pharmaceutical).

  As regards the biochemical and physiological properties, these are due mainly to the association between the sphingolipids (glycosylated or not) and the galactoglycerolipids which act in a combined manner within a cosmetic, dietetic or pharmaceutical preparation. The anti-aging action of this mixture will be emphasized in particular

  cutaneous lipid for topical applications.

  In fact, the presence of the glycosphingolipids and sphingolipids provides significant moisturizing power and plays a role in maintaining the integrity of the intercorneocytic cement. In addition, the galactoglycerolipids present in this lipid mixture, such as digalactosyldiglycerides, are capable of establishing links with the skin proteins providing

  thus improving the suppleness of the skin.

  The anti-collagenase properties have been demonstrated on culture of human dermal fibroblasts; the mixture of sphingolipids and galactoglycerolipids induces a significant increase in the secretion of the specific tissue inhibitor of collagenase (TIMP-1). The polar lipid mixture therefore confers protection of the macromolecules of the skin tissue against enzymatic degradations linked to the

aging.

  In vitro enzymatic tests have shown that the polar lipid mixture (glycosphingolipids, sphingolipids and digalactosyldiglycerides) has anti leukocyte anti-elastase activity while purified ceramides or cerebrosides of animal origin have no anti-elastase activity. There is a particular association in aqueous medium between glycosphingolipids, sphingolipids and

  digalactosyldiglycerides which blocks the activity of the enzyme.

  This property can be put into practice in cosmetics to fight

  against inflammatory skin phenomena linked to UV exposure.

  Pharmaceutical applications can also be envisaged: incorporation of the polar lipid mixture in ointments against

  burns, against skin inflammations such as dermatitis.

  - incorporation in sprays for inhalations in the case of pulmonary emphysema - incorporation in dental gels in the case of gingivitis and periodonthopathies. With regard to the formulations, it is possible to produce an aqueous emulsion at 5 or 10% which is very stable over time. This then allows the incorporation of the lipid mixture into the aqueous phases

  creams, lotions or shampoos.

  The invention therefore also relates to a cosmetic or pharmaceutical composition comprising a plant extract according to the invention,

in particular an aqueous emulsion.

  As an indication, an example of use in a shampoo is given: The hair is a fiber which is both hydrophilic and hydrophobic; in an aqueous medium, it has a strong aptitude for hydration thanks to all of the

  polar, dipolar and hydrogen intramolecular bonds.

  Phytosphingolipids and galactoglycerolipids are amphiphilic molecules and allow to increase the hydration of the hair during shampooing. During drying, new intramolecular bonds can be reconstituted to freeze a new configuration. The more the hair becomes hydrated during washing, the easier it will be to

then format.

  A particularly advantageous property of the oily compositions comprising the plant extract according to the invention lies in the fact that the incorporation of the polar lipid mixture into the water with stirring spontaneously forms micelles or microvesicles, without incorporation of the additional phospholipids or lecithins ( emulsion

oil-in-water or water-in-oil).

  This property makes it possible to protect active principles or vitamins in cosmetic, dietetic or pharmaceutical preparations against enzymatic or radical attacks or against aggression by UV rays or to stabilize the active principles. In the same way, this formation of microvesicles or micelles leads to the encapsulation of colored products, or odorous products, thus making it possible to attenuate the color and the odor of certain compounds.

  used in cosmetic or pharmaceutical formulation.

  The invention therefore also relates to a self-contained composition.

  lipid emulsifier comprising the plant extract according to the invention as well

  one or more active ingredients.

  It also relates to aqueous micellar emulsions

  obtained by contacting with an aqueous phase.

  The invention also relates to a process for preparing

  the plant extract according to the invention.

  The present invention relates to a process for extracting and purifying the lipids associated with the protein fraction of a compound of plant origin, in particular certain cereals such as wheat, corn, barley, rye, sorghum, oats, lipids which have the properties

described above.

  The use of cold polar solvents makes it possible to easily extract the fraction of lipids, adsorbed on the surface of the protein network. However, bound lipids are much more difficult to extract; indeed they are

  entangled in the protein network.

  The choice of solvents and the extraction method are therefore decisive

  in order to obtain an optimal extraction yield.

  The goal is to break down the protein structure to make it accessible

  lipid vesicles by the different extraction solvents.

  The choice of solvents of the present invention was based on their properties to dissolve bound lipids: they are liquid alcohols such as

  methanol, isopropanol, butanol saturated with water, ethanol.

  Determining the proportions of vegetable raw materials / solvent is essential for the quality of the finished product and the extraction yield. The proportions used in the present invention are as follows: - Vegetable raw materials: 1 (weight),

  - Solvent: greater than 6 (volume).

  The starting material is prepared from a plant compound, in particular from cereals, by a process known per se, for

  obtain a viscoelastic mass rich in proteins.

  This protein fraction is added with vigorous stirring in the

solvent chosen.

  The proportions are preferably protein fraction -> 1 (weight) and

  solvent -> greater than or equal to 6 (volumes).

  Stirring is continued for 2 hours.

  In order to obtain a clear oil devoid of water and containing no residual proteins, it is necessary to add before filtration, an adjuvant which will be able to fix the water and retain the proteins. It is advisable to add to the mixture, 15% (weight / volume) of Celite (diatomaceous earth) with stirring and then filter through filter elements of appropriate porosity depending on the raw material used; in the case of wheat,

  carry out filtration on filters with a porosity of 2 jlm maximum.

  This separation leads to the production of a filtrate and a defatted cake. The concentration of the filtrate is obtained by distillation according to a

process known in itself.

  The finished product is then an oil composed of: - Phytosphingolipids and 10 to 20% Glycosphingolipids - Phytoglycoglycerolipids 10 to 20% (including digalactosyldiglycerides) - Triglycerides 50 to 65% - Phospholipids 10 to 15% This oil is clear, light brown in color a characteristic smell of cereals; it is fluid and homogeneous; All of these characteristics allow the incorporation of this oil in cosmetic and dietetic products, without altering either the color or the odor of the finished product. Since the triglyceride content is not negligible, the use of this oil can serve as a support for the incorporation of vitamins or other liposoluble compounds such as vitamin A, vitamin E,

  carotenoids for topical or oral applications.

  Purification of the polar lipid fraction from vegetable oil.

  The polar lipid fraction contained in the vegetable oil which is the subject of the present invention is obtained thanks to the difference of

  solubility of the various lipid compounds in acetone.

  Polar lipids, in particular phytosphingolipids (glycosylated or not) and phytoglycoglycerolipids, precipitate in acetone while

the triglycerides are soluble there.

  The oil is treated with a certain volume of acetone in order to dissolve the triglycerides and to precipitate the polar lipids in the form of a

  fine beige to light yellow powder.

  The volume of acetone used must be large enough so that the concentration of polar lipids in the finished product does not exceed%. The lipid powder is separated from the acetone by filtration: - a compact powder is thus obtained rich in phytosphingolipids, glycosphingolipids and digalactosyldiglycerides, containing 40% (by weight) of residual acetone.

  - an acetone filtrate, rich in triglycerides.

  After elimination of the residual acetone by drying, by a process known in itself, the lipid powder obtained is ground, sieved and packaged. - Phytosphingolipids and 45 to 55% Glycosphingolipids II Phytoglycoglycerolipids 30 to 40% (including digalactosyldiglycerides) Triglycerides 0 to 5% - Phospholipids 10 to 20% The acetone used during the treatment of vegetable oil is enriched in apolar lipids ( especially triglycerides) and also contains a small fraction of polar lipids which remains soluble in acetone. The acetone is removed by distillation, until an oil is obtained.

  fluid, limpid, dark brown in color.

  This oil still contains significant amounts of phytosphingolipids and digalactosyldiglycerides. The composition of this oil is as follows: - Phytosphingolipids and 4 to 9% Glycosphingolipids - Phytoglycoglycerolipids 5 to 10% (including digalactosyldiglycerides) - Triglycerides 75 to 85% - Phospholipids 1 to 6% This oil therefore has hydration properties skin and

  acts against skin aging.

  In cosmetic or dietetic preparations, this oil rich in triglycerides makes it possible to limit water losses; it also makes it possible to transport fat-soluble vitamins such as vitamin E,

  vitamin K, vitamin A and caroteinoids.

  The invention also relates to plant extracts capable of

  to be obtained by the process described below.

  The invention also relates to the use of a plant extract for the manufacture of a topical dermatological or dermatocosmetic composition for the purpose of anti-aging treatment or for moisturizing the skin. By the process described above, the following compositions were obtained: Lipid powder - Phytosphingolipids and 47.6% Glycosphingolipids - Phytoglycoglycerolipids 40.4% (including digalactosyldiglycerides) - Triglycerides 1.0% - Phospholipids 11.0% Oil n 1 - Phytosphingolipids and 16.1% Glycosphingolipids Phytoglycoglycerolipids 16.8% (including digalactosyldiglycerides) Triglycerides 54.9% - Phospholipids 12.8% Oil n 2 Phytosphingolipids and 4.8% Glycosphingolipids Phytoglycoglycerolipids 8, 2% Triglycerides 83, 2% Triglycerides % - Phospholipids 2.7% The total nitrogen dosage of the extracts was carried out knowing that there is one molecule of nitrogen per molecule of ceramides (glycosylated or non-glycosylated). Knowing that there are two thirds of glycosylated phytosphingolipids for one third of non-glycosylated phytosphingolipids, and knowing the molar mass of each of the products (mass spectrum), we were able to determine the percentage of phytosphingolipids and glycosphingolipids

in the different extracts.

  We have also verified by electophoresis that the extracts do not

  did not contain residual proteins.

  Oil in water emulsion The emulsion is prepared by mixing the following ingredients: - Ester of stearic acid and polyoxyethylene ...

  ........... 3.85 g with 8 moles of ethylene oxide - mono and glycerol distearate ...................... ............. 0.7 g - cetyl alcohol .............................. ........................ 2, 45 9 volatile cyclic dimethylpolysiloxane ................... ........ 5 9 mixture of cetostearyl alcohol ............................... 5 g and alkyl sulphate sodium - oils n 1 or 2 ....................... DTD: ................... ......... 2.5 to 5 g - carboxyvinylpolymer "Carbopol 941" ....................... 0.2 g - Preservative ............. DTD: ................................... ......... 0.3 g - Perfume ............. DTD: .................... ................................ 0.4 g water ........ DTD: ... .. qs .................... 100 g Gel - 96% ethyl alcohol .... DTD: ............ ............................ 15 g carboxyvinylpolymer "Carbopol 941" ............... ........ 30 g - polar lipid powder 0.1 to 1 g - triethanolamine 20% in water ..................... ........ 3 g - preservative ........... DTD: ......................... ..................... 0.2 g - fragrance ........... DTD: .......... ............................................ 0.4 g water. ..... DTD: ....... qsp ................... 100 g Glycerolmonostearate cream combined with ......... .................. 6 g polyoxyethylene emulsifier - polyoxyethylene sorbitan monostearate ....... DTD: ............... 2 g (20 moles of ethylene oxide) - stearic acid ................................... 2 g ................... 2 cetyl alcohol .......................... ........................... 1, 2 g - liquid lanolin ................ .................................... DTD: .. 6g perhydrosqualene ........ ........................................ DTD: ... 30 9 - methylphenylpolysiloxane. .................................. DTD: ...... 1 g - triethanolamine .... ........................................ DTD: ........ ... 0.1 g - oil n 1 or 2 ........................ to 4 ....... DTD: .... ........ .............. 2 4 g - or polar lipid powder ........... DTD: ............... .. 0.5 to 2 g preservative ........................ DTD: ............... .................. 0.3 g - perfume ...................... DTD: .. ....................................... 0.4 g - water ..... ........... DTD: qs ................... 100 g..DTD:

Claims (13)

  1. Plant extract of cereals based on polar lipids comprising a mixture of phytosphingolipids and phytoglycoglycerolipids in a   weight ratio between 0.5 and 2.   2. Cereal plant extract according to claim 1, characterized in that the phytosphingolipid and phytoglycoglycerolipid ratio is between 1 and 1.8.   3. Cereal plant extract according to one of claims 1 or 2,   characterized in that it comprises in percentage by weight: Phytosphingolipids and 45 to 55% Glycosphingolipids Phytoglycoglycerolipids 30 to 40% (including digalactosyldiglycerides) Triglycerides 0 to 5% - Phospholipids 10 to 20%   4. Cereal plant extract according to one of claims 1 or 2,   characterized in that it comprises in percentage by weight: Phytosphingolipids and 10 to 20% Glycosphingolipids Phytoglycoglycerolipids 10 to 20% (including digalactosyldiglycerides) Triglycerides 50 to 65% - Phospholipids 10 to 15%   5. Cereal plant extract according to one of claims 1 or 2,   characterized in that it comprises in percentage by weight: Phytosphingolipids and 4 to 9% Glycosphingolipids Phytoglycoglycerolipids 5 to 10% (including digalactosyldiglycerides) Triglycerides 75 to 85% - Phospholipids 1 to 6%   6. Cereal plant extract according to one of claims 1 to 5,   characterized in that it is capable of being obtained by the following steps: - obtaining a plant mass rich in proteins, - dissolving the lipid part by means of a first suitable solvent, optionally in the presence of an adjuvant capable of fixing water and retain the proteins, - recover the purified lipid part comprising in percentage by weight: - Phytosphingolipids and 10 to 20% Glycosphingolipids - Phytoglycoglycerolipids 10 to 20% (including digalactosyldiglycerides) - Triglycerides 50 to 65% - Phospholipids 10 to 15 % - precipitate the polar lipid part using an appropriate solvent, - recover the polar lipid part comprising in percentage by weight: - Phytosphingolipids and 45 to 55% Glycosphingolipids - Phytoglycoglycerolipids 30 to 40% (including digalactosyldiglycerides) - Triglycerides 0 to 5 % - Phospholipids 10 to 20% - possibly recover the apolar lipid part comprising in percentage in poi ds: - Phytosphingolipids and 4 to 9% Glycosphingolipids Phytoglycoglycerolipids 5 to 10% (including digalactosyldiglycerides) Triglycerides 75 to 85% - Phospholipids 1 to 6%   7. Cereal-based plant extract according to one of claims   above, characterized in that the cereals are chosen from wheat, barley, oats, rye, corn, sorghum.   8. Cereal-based plant extract according to one of claims   above, characterized in that it induces a significant increase in the secretion of the tissue-specific collagenase inhibitor (TIMP-1)   for concentrations equal to or greater than 5 pg / ml.   9. Cereal-based plant extract according to one of claims 1   to 7, characterized in that it has a human leukocyte anti-elastase activity, 50% inhibition of the enzymatic activity for a concentration of approximately 55 gg / ml.   10. Cosmetic composition for external topical application   comprising a plant extract according to one of claims 1 to 9 and   possibly one or more active ingredients.   1l. Self-emulsifying composition for cosmetic, dietetic or pharmaceutical use to protect or stabilize the active ingredients, characterized in that it comprises a plant extract according to one of   claims 1 to 9 and one or more active ingredients.   12. Water in oil or oil in water emulsion obtained by bringing the composition according to claim 11 into contact with an aqueous phase.   13. Use of a plant extract according to one of claims 1 to   9 for the manufacture of a dermatological, dermatocosmetic or pharmaceutical composition for the purpose of anti-aging treatment or for   moisturizing the skin or as an anti-inflammatory.   14. Nutritional supplement or dietetic preparation including   a plant extract according to one of claims 1 to 9.