METHOD FOR PRODUCING AN EXTRACT OF A MATRIX OF VEGETABLE ORIGIN BY EXTRUSION WITH A HYDROTROPE SOLUTION

Abstract

The invention relates to a method for producing an extract of a matrix of vegetable origin, particularly a plant, characterised in that the matrix of vegetable origin undergoes a mechanical treatment consisting in extruding the matrix of vegetable origin in an extruder, in association or not with a heat treatment, in the presence of an aqueous solution containing at least one hydrotrope agent, particularly at a concentration at least equal to the minimum hydrotrope concentration thereof, followed by an operation of recovering the extract.

Claims

1. Method for obtaining an extract of a vegetable matrix, particularly plant matrix, characterized in that the vegetable matrix is subjected to mechanical treatment consisting of extruding the vegetable matrix in an extruder, associated or not with heat treatment, in the presence of an aqueous solution containing at least one hydrotropic agent, in particular at a concentration at least equal to the minimum hydrotropic concentration, followed by an operation to recover the extract.

2. The method according to claim 1, characterized in that the hydrotropic agent is of ionic type, selected in particular from among sodium n-butyl benzene sulfonate, sodium cumene sulfonate, sodium paratoluene sulfonate or sodium xylene sulfonate.

3. The method according to claim 1, characterized in that the hydrotropic agent is of non-ionic type, preferably agri-sourced, in particular an alkyl-(poly)glycoside of general formula Alk-O-Zp, where: Alk designates a hydrophobic, aliphatic hydrocarbon fragment, saturated or unsaturated, straight-chain or branched, having 3 to 7 carbon atoms, and Z is a hydrophilic glycoside group such as glucose, xylose and arabinose, and 1<p<5.

4. The method according to claim 1, characterized in that said heat treatment is conducted at temperatures between 20 C. and 200 C., preferably between 60 C. and 120 C.

5. The method according to claim 1, characterized in that the plants subjected to thermomechanical treatment in the presence of an aqueous solution of a hydrotropic agent, are composed in full or in part of the above-ground parts and/or below-ground parts of dry plants or fresh plants that are whole, fragmented or ground.

6. The method according to claim 5, characterized in that the plant parts are represented by the above-ground parts such as the stems, branches, leaves, fruit, seeds and/or flowers; and/or the below-ground parts such as rhizomes, roots and/or bulbs.

7. The method according to claim 1, characterized in that the dry or fresh plants subjected to thermomechanical treatment in the presence of an aqueous solution of a hydrotropic agent, are selected from among the fruit of Physalis peruviana, seeds of Embelia ribes, leaves of Myrtus communis, leaves of Eucalyptus globulus, pericarps of Garcinia mangostana, female inflorescences of Humulus lupulus, bark of Cinchona sp., above-ground parts of Urtica dioica, above-ground parts of d'Helichrysum spp., fruit of Vanilla spp., rhizomes of Zingiber officinale, rhizomes of Curcuma spp., rhizomes of Piper methysticum, leaves of Piper spp, fruits and leaves of Olea europaea.

8. The method according to claim 1, characterized in that the plants undergo pre-treatment before extrusion, treatment by ultrasound, microwave, enzymatic digestion, maceration in the hydrotropic solution, preparation of the plant such as cryogenic grinding, fragmentation, grinding, in particular maceration in the hydrotropic solution.

9. The method according to claim 1, characterized in that the recovered extract is subjected to a subsequent step of clarification and/or filtration.

10. The method according to claim 1, characterized in that the recovered extract is diluted, concentrated, dried or stored as such with the addition of a suitable preserving agent.

11. The method according to claim 1, characterized in that the recovered extract is diluted in a sufficient volume of water to recover a dry extract enriched with lipophilic compounds.

12. The method according to claim 1, characterized in that extrusion is implemented in a twin-screw extruder.

13. The method according to claim 12, characterized in that the twin-screw extruder comprises a first zone with co-rotating and co-penetrating twin screws, where trituration of said plants takes place.

14. The method according to claim 12, characterized in that the twin-screw extruder comprises a second twin-screw zone where solid/liquid separation takes place.

15. The method according to claim 1, characterized in that said extruder comprises at least one barrel and preferably several successive adjacent barrels.

16. Food, cosmetic and/or pharmaceutical compositions containing a total vegetable matrix extract or having a concentration of lipophilic compounds obtained by implementing the method according to claim 1.

17. The compositions according to claim 16, characterized in that they are prepared in a form suitable for topical administration.

18. The compositions according to claim 16, characterized in that they are prepared in a form suitable for oral administration.

Description

EXAMPLES

Example 1: Myrtle Extract

[0093] 1.3 kg of dry leaves of Myrtus communis were fed into the first barrel of a Clextral BC45 twin-screw extruder at a rate of 8 kg/H. An aqueous solution of amyl xylosides was then added at 1.5 mol/L and at a rate of 24 L/H. The temperature applied to the different barrels was 60 C./60 C./60 C./60 C./60 C. After 5 minutes, the extract of Myrtle leaves was recovered at the outlet by means of a filtering barrel allowing solid/liquid separation. After clarification, the dry Myrtle extract was obtained with a yield of 81% relative to the solvent used and 1184% relative to the plant feed. The solution was diluted in 4 volumes of water. After centrifugation, the residue corresponding to the extract enriched with Myrtle was obtained with a weight yield of 1.2% relative to plant feed.

[0094] For comparison, 1.3 kg of dry leaves of Myrtus communis were extracted in water under the same conditions. After clarification, the Myrtle extract was obtained with a yield of 8.5% relative to plant feed.

[0095] The myrtucommulones B, S and A were assayed in both extracts and in two extracts obtained in a reactor.

TABLE-US-00001 Content of myrtu- commulones Ratio Extraction in extract [Myrt. B]/ Extract time Yield (m/m) [Myrt. A] Amyl xyloside 5 1.2% 9.9% 2.3 1 W/3 V extrusion + precipitation by dilution Amyl xyloside 3 H 2.1% 8.9% 1.9 1 W/7 V reactor + precipitation by dilution Isopropyl acetate 2 H 3.1% 7.3% 3.1 1 W/8 V reactor Water 1 W/3 V 5 8.5% .sup.0% / extrusion

[0096] Although the extraction weight yield is lower, the extract obtained by extrusion with a plant weight/solvent volume ratio that is non-feasible in a reactor (insufficient for plant wetting) and with an extremely rapid extraction time, has a slightly higher concentration of myrtucommulones than obtained with conventional extraction in a reactor with the same solvent. It also has a higher concentration of myrtucommulones than the extract obtained with isopropyl acetate in a reactor. Myrtucommulone A, the most apolar, is twice richer in the hydrotropic extract obtained by extrusion than in the extract with isopropyl acetate, which evidences the selectivity of the method. The extract obtained by extrusion with water without amyl xylosides does not allow the extraction of compounds of interest.

Example 2: Extract of Helichrysum gymnocephalum by Extrusion

[0097] 5 kg of the entire, dried above-ground parts of Helichrysum gypmnocephalum were fed into the first barrel of a Clextral BC45 twin-screw extruder, at a rate of 10 kg/H. An aqueous solution containing 50% heptylglucoside m/m (1.5M) was added at a rate of 60 L/H. The temperature applied to the different barrels was 60 C./60 C./60 C./60 C./60 C. After 5 minutes, the Helichrysum extract was recovered at the outlet of the extruder by means of a filtering barrel allowing solid/liquid separation. After clarification, the Helichrysum extract was obtained with a yield of 69.5% relative to the solvent used and 407% relative to plant feed.

TABLE-US-00002 Content of apolar flavonoids in the non- Extraction concentrated, non- Extract time Yield dried extract (m/m) Heptylglucoside 5 407.1% 0.13% 1 W/6 V extrusion Heptylglucoside 5 196.1% 0.15% 1 W/3 V extrusion Heptylglucoside 2 H 1450% 0.10% 1 W/15 V reactor Water 1 W/6 V 5 .sup.573% 0% extrusion

[0098] Although the yields are lower, the quality of the extract obtained by extrusion with volumes of solvent up to 5 times lowera weight/solvent ratio non-feasible in a reactor (insufficient for plant wetting)and with an extremely rapid extraction time, is comparable with that obtained by conventional extraction with the same solvent. The extract obtained by extrusion with water without heptylglucoside does not allow extraction of these compounds of interest.

Example 3: Extract of Dry Nettle and Fresh Nettle

[0099] 0.67 kg of the above-ground parts of nettles were fed into the 1.sup.st barrel of a Clextral BC45 twin-screw extruder at a rate of 8 kg/H. An aqueous solution containing 10% heptylglucoside m/m was added at a rate of 36 kg/H, which corresponds to extraction with a weight/volume ratio of 1/4.5, non-feasible in batch operation having regard to the low density of the above-ground parts of dry nettles. The temperature applied to the different barrels was 60 C./60 C./60 C./60 C./60 C. After 5 minutes, the dry nettle extract was recovered at the outlet of the extruder by means of a filtering barrel allowing solid/liquid separation. After clarification, the nettle extract was obtained with a yield of 48.7% relative to the solvent used and 218% relative to plant feed.

[0100] 4.4 kg of fresh nettle, above-ground parts were fed into the 1st barrel of a Clextral BC45 twin-screw extruder at a rate of 33 kg/H. An aqueous solution containing 10% heptylglucoside m/m was added at a rate of 17 kg/H, which corresponds to extraction with a weight/volume ratio of 1/0.5, but in fact 1/6 if consideration is given to the water content of the plant. This is impossible to carry out in batch operation. The temperature applied to the different barrels was 60 C./60 C./60 C./60 C./60 C. After 8 minutes, the fresh nettle extract was recovered at the outlet of the extruder by means of a filtering barrel allowing solid/liquid separation. After clarification, the nettle extract was obtained with a yield of 162.6% relative to the solvent used and 85% relative to plant feed.

[0101] The 2 extracts obtained were then acidified with sulfuric acid qs pH3 and diluted 6 times in water to obtain a final heptylglucoside concentration of 1.4%. Turbidity occurred and a residue was collected after centrifugation for 20 at 3500 rpm.

[0102] Thin layer chromatography analysis in appended FIG. 1 shows the presence in these 2 extracts of polar lipids such as galactolipids and sterols, these bands not being present for the extract obtained by extrusion using only water under the same conditions (extrusion dry/fresh plant, plant and solvent feed rates). MGDG designates mono-galactosyldiacylglycerol and DGDG designates di-galactosyldiactylglycerol.

Example 4: Capsule

[0103]

TABLE-US-00003 Myrtle extract as in Example 1: 200 mg Starch: 45 mg Magnesium stearate: 2 mg

Example 5: Cream

[0104]

TABLE-US-00004 Helichrysum gymnocephalum extract as in Ex. 2: 0.5-3% Tribehenin PEG- 20 esters .sup.2-7% Isodecyl neopentanoate .sup.2-9% Glycerine 0.5-10% Glycol palmitate .sup.1-6% Cetyl alcohol 0.5-3% Disodium EDTA 0.05-0.25% Preserving agents 0.5-3% Fragrance 0.2-0.5%.sup. Xanthan gum 0.1-0.4%.sup. Water qs