WO1998048820A1

WO1998048820A1 - White oat colloidal extract and method for making same

Info

Publication number: WO1998048820A1
Application number: PCT/FR1998/000826
Authority: WO
Inventors: Max Rouanet; Jean-Jacques Potherat; Henri Cousse
Original assignee: Pierre Fabre Dermo-Cosmetique
Priority date: 1997-04-28
Filing date: 1998-04-24
Publication date: 1998-11-05
Also published as: FR2762515B1; FR2762515A1

Abstract

The invention concerns a method for making a white oat colloidal extract comprising the following steps: using cultivated oat seeds; stabilising by at least one operation whereby dry vapour is injected followed by sudden cooling, preferably at about room temperature; pinning and drying; breaking and eliminating the bran; dimensional selecting of particles.

Description

"Colloidal extract of white oats and its manufacturing process"

The present invention relates to a new colloidal extract of white oats and its manufacturing process.

The colloidal oat extract is a powder resulting from the grinding and possibly other mechanical treatments of oat seeds, the raw material used is generally chosen from the species Avena sativa L and Avena byzantina C. Koch.

The colloidal oat extract is used in various types of cosmetology, dermatology and pharmacy formulation, in particular in preparations which can be used without rinsing, such as creams, gels, solutions or else in formulations with rinsing, for example shampoos. .

The functions of colloidal oat extract in galenical preparations are numerous. They can be classified into two main categories where they appear respectively as a true active substance, or as an excipient either by mass or by controlled release.

When the colloidal oat extract appears as a real active substance, it can in particular perform the following functions:

Protective function: avoids and slows down contact between the epidermis and the outside environment (clothing).

Hydrating function: slows the loss of water by forming a colloidal and hydrolipidic film. To this film-forming effect, there is added penetration of the hydrolipid emulsion into the superficial horny layers of the epidermis, oats containing surfactant compounds, which gives it an emollient effect.

Radical protection function by partial absorption of radiation creating oxygenated or nitrated free radicals.

Regenerative function. Buffer function.

Dilution function of aggressive agents and external irritants: by dilution in the hydrolipidic film, by absorption of the irritant agent on the colloid type structure.

When colloidal oat extract is used as an excipient, it essentially performs the following functions:

Function prolonged release excipient that the preparation applied to the skin consists of an aqueous phase or a water in oil or oil in water emulsion. Oat colloids are capable of gradually fixing and releasing (pH or water fixation) extremely diverse hydrophilic and lipophilic compounds and subsequently releasing by at least three mechanisms:. dehydration, change in pH or ionic strength, desorption. Colloidal oats are by their nature indicated for the treatment of the skin and mucous membranes whatever the conditions in which they are found. It can be considered as perfectly bio compatible with these two tissues, even if these are abraded, burned, irradiated ... and belong to infants, children, adolescents, adults, the elderly, whatever their pigmentary status.

On the skin, colloidal oats are particularly indicated in all the states where one seeks: an emollient and hydrating action, a soothing activity on irritated skin. antipruritic activity, on healthy, abraded, burned or irradiated skin, erythrodesquamative, bullous, vesicular.

Colloidal oats are particularly indicated in gynecology in all pelvovaginal or anogenital manifestations or in daily hygiene in the girl child, the woman, in peri and in postmenopause. Colloidal oats are particularly indicated for the protection of the lips.

The object of the present invention therefore relates to a colloidal extract of oats whose anti-inflammatory properties objectified by the inhibition of the formation of prostaglandins have been increased by a defined content of anti-inflammatory free fatty acids, and / or by a defined content of certain protein fractions.

The object of the invention results from a manufacturing process based on the application of different operational steps to obtain a colloidal extract of oats specifically enriched in certain fractions or active agents having demonstrated pharmacological properties and of interest in dermo-cosmetology. .

In accordance with the present invention, the method for manufacturing a colloidal extract of white oats is characterized in that it involves the implementation of the following operations: use of seeds of Avena satina, - stabilization by at least one operation dry steam injection followed by sudden cooling, preferably at. a temperature close to room temperature, rolling and drying, grinding and elimination of bran, - and dimensional selection of the particles.

The method according to the invention is also characterized by a certain number of other details which will appear on reading the detailed examples given below.

Oat seeds having a moisture content of more than 8% and preferably more than 12% will preferably be used.

Advantageously, freshly harvested oat seeds or seeds which have not undergone any treatment are used for their preservation. In practice, it has proved advantageous to use oat seeds having undergone ^a preliminary operation of removing pericarp of ornaments, especially the husks and the pericarp hairs.

In the context of the present invention, the stabilization operation applied to white oat seeds can be carried out either on all the seeds before any grinding operation, or on only part of the seeds which have not undergone any operation grinding.

According to a variant of the process according to the invention, the stabilization operation is carried out on part or all of the seeds which have undergone a first flattening and maturation operation.

In the context of such a variant, a total hydrolysis is carried out followed by stabilization on a first aliquot of seeds to obtain a maximum concentration of free fatty acids, followed by stabilization of the other aliquot while practically avoiding any hydrolysis in order to obtain a minimum concentration of free fatty acids, and in that the two aliquots thus treated are mixed in appropriate proportions.

In general, the stabilization operation is obtained by one or more dry steam injection operations under conditions allowing the seeds to be brought advantageously to a temperature of the order of 90 to 95 ° C.

The operation of grinding oat seeds is essential and advantageously carried out so as to obtain at most about 20% of refusal to pass through a sieve of 800 μm. These particles larger than around 800 μm are generally eliminated.

The dimensional selection of the particles is advantageously carried out so as to recover all of the particles smaller than 100 μm with a tolerance of 10 to 20% of refusal to pass through a sieve at 100 μ.

As a variant, the dimensional selection of the particles is carried out by applying the following standards: - 100% acceptance at 100 μm, and / or 95% acceptance at 50 μm, and / or 80% acceptance at 20 μm.

In accordance with an advantageous variant of the process according to the invention, the particles smaller than about 300 μm are recycled for subsequent spraying and micronization and then added, preferably at a level of 5 to 20% by weight, to the particles of smaller dimension at 100 μm.

The invention also extends to the colloidal extract of white oats as it results in particular from the implementation of the method described above.

The colloidal extract of white oats according to the invention has a prolamine content of 5 to 25% of the protein mass, and / or a free fatty acid content of 20 to 99% of the fraction of lipophilic lipids.

The modified protein content of these extracts is obtained by reincorporation before grinding - and before dimensional selection of part of the particles of the pericarp of white oat seeds.

Likewise, the modified content of free fatty acids in the extract according to the invention is obtained by mixing, before dimensional selection, the various colloidal extracts stabilized or having undergone controlled lipolysis.

Finally, the invention extends to a complex formed by the association of the extract described above with an active principle, lipophilic or hydrophilic, which is complexed with the amylose fraction of the extract.

The active ingredient complexed with the colloidal oat extract according to the invention can be chosen from compounds with anti-free radical properties such as tocopherol and carotenes as well as antiseptic compounds such as chlorhexidine or chlorhexidine gluconate, they then intervene. in the complex up to a content of 0J to 10% o by mass. The extracts which are the subject of the present invention therefore find their use in the manufacture of cosmetic or dermatological compositions endowed with protective or hydrating properties of the skin and mucous membranes.

The invention will be better understood on reading the detailed examples given below:

EXAMPLE 1:

Role of proteins in the anti-inflammatory activity of a colloidal oat extract obtained according to the invention:

The grain of oats, unlike the grain of wheat, does not have an aleurone layer, nor of germ perfectly anatomically individualized, on the other hand a prolonged grinding makes it possible to isolate four types of particles when the oats have been previously brought with a water content much less than 10%: very fine particles, practically less than 20 μm corresponding to the almond essentially composed of starch, particles from 100 to 300 μm, corresponding to individual cells, rich in proteins, particles of 300 to 800 μm corresponding to clusters of cells in the pericarp, large particles in fact not treated by the cylinders.

Intree oats, white oats, can be used in the described protocol. Stabilization by vapor phase is carried out at the start of the process. The grinding is carried out until a rejection in the 800 μm sieve of around 20% is obtained. Three particle sizes are individualized:

800 μm>p> 300 μm Fraction A rich in 300 μm>p> 100 μm Fraction B proteins 100 μm> p Fraction C Operating procedure :

A suspension of SVK 14 human keratinocytes (1 x 10 6 cells / 2 ml) in MEM GEBCO 076 01 300 N culture medium containing 10% fetal calf serum: Dutscher 300 121 is distributed at the rate of 1 x 10 6 cells per well and incubated for 16 hours at 37 ° C in an atmosphere containing 5% CO ² .

An oat fraction "solution" is prepared with the liquid phase, the MEM medium without fetal calf serum. This "solution" is at 1.66 P / V. This solution is introduced into the culture to obtain a final concentration in oat fraction of 0J%. For each fraction, 3 wells are treated. After 45 min of contact, the calcium ionophore A23187: SIGMA C 7522 is added at a rate of 5 μm.

After 5 hours, the liquids supernatant the cultures are collected well by well and centrifuged at 3000 rpm.

The production of 6 KF 1 α is measured by the Elisa method (Eurmex) for each well.

RESULTS

CONCLUSIONS:

The colloidal extract (fraction C) of oats Intrée has a clear activity on the secretion of prostagland of the PGF type.

Fraction B corresponds to the cells of the deep layer of the epicarp. It contains components capable of completely inhibiting the secretion of PGF at this concentration.

Fraction A also has inhibitory properties, but is not grindable below 100 μm economically.

Fraction B can be more finely ground by micronization and incorporated into fraction C which increases the anti-inflammatory properties of the colloidal oat extract, without modifying its organoleptic properties but appreciably modifies the fiber content (5 <x < 10) and the ash rate.

EXAMPLE 2:

Role of proteins in the anti-inflammatory activity of a colloidal oat extract obtained according to the invention.

Following the previous example, during the process, particles greater than 800 μm are eliminated, particles greater than 300 μm are again sprayed and micronized to obtain a rejection at 100 of less than 20% (10 to 20%).

The anti-inflammatory activity of the colloidal extract obtained (c) is compared with that of a standard colloidal extract (B) and that of an oatmeal (A).

Operating procedure :

A suspension of SVK 14 human keratinocytes (1 × 10 6 cells / 2 ml) in MEM GIBCO 076 01 300 N culture medium containing 10% serum fetal calf: Dutscher 300 121 is distributed at the rate of 1 × 10 6 cells per well and incubated for 16 hours at 37 ° C. in an atmosphere containing 5% CO 2.

The production of 6 KF 1 α is measured by the Hisa method (Eurmex) for each well.

RESULTS

CONCLUSIONS

The addition of a 100 μm screen reject grind considerably increases the anti-inflammatory properties of a colloidal extract. oats. Practically this addition can be from 5 to 20% without the organoleptic aspects of the colloidal extract being modified.

EXAMPLE 3:

Role of the nature of proteins in the anti-inflammatory activity of a colloidal oat extract obtained according to the invention:

The colloidal extracts evaluated in the previous example are titrated in total proteins and in sub-fractions. The subfractions are then evaluated for their anti-inflammatory activities.

The results show that the observed effect is linked to a change in the nature of the protein subclasses by the operation of grinding and micronization of the refusal.

Total proteins in% and sub-fractions in% of PT:

These sub-fractions have different anti-inflammatory properties

Operating procedure :

A suspension of SVK 14 human keratinocytes (1 × 10 6 cells / 2 ml) in MEM GIBCO 076 01 300 N culture medium containing 10% fetal calf serum: Dutscher 300 121 is distributed at a rate of 1 × 10 6 cells per well and incubated for 16 hours at 37 "C in an atmosphere containing 5% CO ² .

After 5 hours, the liquids supernatant the cultures are collected well by well and centrifuged at 3000 rpm. The production of 6 KF 1 α is measured by the Hisa method (Eurmex) for each well.

The total proteins are, dosed by the method of Cluskey (1973), extraction with sodium hydroxide (sodium hydroxide solution at 0.015 N) from a defatted product and precipitation with hydrochloric acid.

The fractions are dosed according to a protocol developed from the publications of Ma (1983) Wu (1977) and Pernollet (1982): from the delipidated ground material, the albumins and the globulins are extracted with a solution of calcium chloride at 0.5 M. Hles are then separated by dialysis against distilled water at 40 ° C: the globulins precipitate, the albumin is precipitated by 52% ethanol.

The extraction residue is taken up in alcohol, the prolamins go into solution.

The extraction residue is taken up in dilute sodium hydroxide: the glutellins go into solution.

EXAMPLE 4:

Role of free fatty acids in the anti-inflammatory activity of the colloidal oat extract obtained according to the invention:

Rhéalba oats, naked white oats, are used. Stabilization by "vapor phase" is not carried out. The grinding is carried out until a rejection in the sieve 300 of the order of 50% is obtained.

Two particle sizes are individualized by turboseparation: p <100 μ = Fraction A

100 μm <p = Fraction B

An aliquot of A and B is exposed to 121 ° C for 150 min (sterilization). Operating procedure :

A suspension of SVK 14 human keratinocytes (1 × 10 6 cells / 2 ml) in MEM GIBCO 076 01 300 N culture medium containing 10% fetal calf serum: Dutscher 300 121 is distributed at a rate of 1 × 10 6 cells per well and incubated for 16 hours at 37 ° C in an atmosphere containing 5% CO ² .

RESULTS

CONCLUSIONS:

Fraction B contains compounds capable of inhibiting the secretion of PGF. These compounds are thermostable. This activity is related to the level of free fatty acids, which appeared during the process, due to the initial non-stabilization.

EXAMPLE 5:

Increase in buffering capacity: the raw materials are Intrée and Rhéalba, the grains have a water content at the start of the process of between 10 and 12%.

Lot A is thermally stabilized before the start of the process. Lot B is not stabilized. Lot C is stabilized 20 hours after grinding before turbo separation.

The analysis of the lipid pool provides the results below:

Operating procedure

Hexane extraction: extraction of approximately 40 g exactly measured with a soxhlet using 600 ml of Exane, the evaporation residue corresponds to the lipids delivered. Ether extraction: release of the "lipids" of approximately 2 g of ground material exactly measured by contact for 90 min with hydrochloric acid at 70 ° C.

Ethanol extraction of the residue: ether extraction of the residue and of the alcoholic phase. The evaporation residue corresponds to the total lipids.

CONCLUSIONS:

The increase in bound lipids corresponds to the formation of a complex between amylose and free fatty acids.

This controlled hydrolysis and the inclusion of fatty acids in amylose provide a buffering capacity and an acidic pH which is advantageous for skin application both for the insertion of slightly acidic or alkaline components and for improving biocompatibility.

For example, this pH and this buffering capacity are described below for the three products:

EXAMPLE N ° 6:

Incorporation of an active ingredient during the dimensional selection of the colloidal extract:

Amylose is capable of forming complexes with lipophilic and hydrophilic compounds: in particular, it is advantageous to incorporate, at this stage of the process, active agents to have a residual effect of the preparation and / or better conservation of the 'colloidal extract.

Substances such as tocopherol and carotenes have a protective role against the oxidation of the lipid pool of colloidal oat extract, they also have a treating role in the skin.

Substances such as chlorhexidine (gluconate) have a protective role against bacterial oxidation in the colloidal oat extract during storage. They also have a treating, antiseptic, cutaneous role.

By way of illustration, four diagrams of implementation of the method according to the invention will be indicated below, making it possible in particular to adjust the protein and fatty acid contents according to the specific applications envisaged.

Claims

1.- Process for manufacturing a colloidal extract of white oats, characterized in that it involves the implementation of the following operations: use of Avena satina seeds, stabilization by at least one dry steam injection operation followed sudden cooling, preferably at a temperature close to room temperature, rolling and drying, grinding and elimination of sound, and dimensional selection of the particles.

2.- Method according to claim 1, characterized in that oat seeds are used having a moisture content greater than about 8%, and preferably, greater than about 12%.

3.- Method according to one of claims 1 and 2, characterized in that one uses freshly harvested oat seeds and / or having undergone no treatment for their preservation.

4.- Method according to one of claims 1 to 3, characterized in that the oat seeds used undergo a preliminary operation of removing ornaments from the pericarp, in particular glumes and hair from the pericarp.

5.- Method according to one of claims 1 to 4, characterized in that the stabilization operation is carried out on all of the seeds before any grinding operation.

6.- Method according to one of claims 1 to 4, characterized in that the stabilization operation is carried out on only part of the seeds which have not undergone any grinding operation.

7.- Method according to one of claims 1 to 4, characterized in that the stabilization operation is carried out on part or all of the seeds having undergone a first operation of flattening and maturation (oatmeal? .).

8.- Method according to one of claims 1 to 4, characterized in that a total hydrolysis is carried out followed by stabilization on a first aliquot of the seeds to obtain a maximum concentration of free fatty acids, followed by stabilization of the other aliquot, practically avoiding any hydrolysis in order to obtain a minimum concentration of free fatty acids, and in that the two aliquots thus treated are mixed in appropriate proportions.

9.- Method according to one of claims 1 to 8, characterized in that the stabilization operation is obtained by injection (s) of dry steam under conditions allowing to bring the seeds to a temperature of about 90 at 95 ° C.

10.- Method according to one of claims 1 to 9, characterized in that the operation of grinding the seeds is carried out so as to obtain at most about 20% of refusal to pass through a sieve of 800 μm.

11- Method according to one of claims 1 to 10, characterized in that all of the particles greater than about 800 microns is removed.

12.- Method according to one of claims 1 to 11, characterized in that the dimensional selection of the particles is carried out so as to recover all of the particles less than 100 μm, with a tolerance of 10 to 20% of refusal of passing through a sieve at 100 μm.

13.- Method according to one of claims 1 to 10, characterized in that the dimensional selection of the particles is carried out by applying the following standards: - 100% acceptance at 100 μm, and / or 95% acceptance at 50 μm, and / or 80% acceptance at 20 μm.

14.- Method according to one of claims 1 to 13, characterized in that particles smaller than about 300 microns are recycled for a subsequent pulverization and micronization, then added, preferably up to 5 ^to 20% by weight, to particles smaller than 100 μm.

15.- Colloidal extract of white oats, characterized in that it has a prolamine content of 5 to 25% of the protein fraction.

16.- Extract according to claim 15, characterized in that it has a free fatty acid content of 20 to 99% of the fraction of the linked lipids.

17.- Extract according to one of claims 15 and 16, characterized in that it is capable of being obtained by the process according to one of claims 1 to 14.

18.- Extract according to claim 17, characterized in that it has a modified protein content by reincorporation, before grinding and before dimensional selection, of a portion of the pericarp particles of white oat seeds.

19.- Extract according to one of claims 17 and 1 8, characterized in that it has a modified content of free fatty acids, obtained by mixing, before dimensional selection, different colloidal extracts stabilized or having undergone controlled lipolysis.

20.- Complex formed by the association of an extract according to one of claims 15 to 19 and of a lipophilic or hydrophilic active principle complexed with the amylose fraction of the extract.

21.- Complex according to claim 20, characterized in that said active principle is chosen from compounds with anti-free radical properties such as tocopherol and carotenes, as well as antiseptic compounds such as chlorhexidine salts, for example chlorhexidine gluconate.

22.- Complex according to claims 20 and 21, characterized in that the active principle is present in said complex at the level of OJ at 10% o.

23.- Use of the extract according to claims 15 to 19 or of the extract obtained by implementing the method according to one of claims 1 to 14 for the manufacture of a cosmetic or dermatological composition endowed with protective properties and / or moisturizers of the skin and mucous membranes.