METHOD FOR PRODUCING AN EXTRACT OF A MATRIX OF VEGETABLE ORIGIN WITH A NON-IONIC AMPHIPHILIC COMPOUND AS EXTRACTION ADJUVANT IN AN AQUEOUS MEDIUM

Abstract

The invention relates to a method for producing an extract of a matrix of vegetable origin, particularly a plant, involving a solid-liquid extraction by means of an aqueous solution containing at least one, preferably agro-sourced, non-ionic amphiphilic compound, at a concentration at least equal to the minimum hydrotrope concentration thereof.

Claims

1. A method for producing a vegetable matrix extract, in particular a plant extract, involving solid-liquid extraction with the aid of an aqueous solution containing at least one non-ionic amphiphilic compound, preferably agro-sourced, at a concentration at least equal to the minimum hydrotrope concentration thereof.

2. The method as claimed in claim 1, characterized in that the aqueous solution containing said non-ionic amphiphilic compound constitutes the only extraction solvent used.

3. The method as claimed in one of claims 1 to 2, characterized in that the solid-liquid extraction is performed by maceration of the plant in said aqueous solution containing at least one non-ionic amphiphilic compound, maintained under stirring.

4. The method as claimed in one of claims 1 to 2, characterized in that the solid-liquid extraction is performed under microwaves, under ultrasound, or in a countercurrent process.

5. The method as claimed in claim 4, characterized in that the minimum hydrotrope concentration of the non-ionic amphiphilic compound in said aqueous solution is between 1 and 10 times, preferably between 1 and 6 times, more preferably between 1 and 2 times, even more preferably between 1.4 and 1.8 times the minimum hydrotrope concentration.

6. The method as claimed in one of claims 1 to 5, characterized in that the non-ionic amphiphilic compound is present in said aqueous solution at a concentration of less than 60% by weight relative to the weight of said solution, preferably less than 50% by weight relative to the weight of said solution, more preferably less than 40% by weight relative to the weight of said solution, even more preferably less than 30% by weight relative to the weight of said aqueous solution.

7. The method as claimed in one of claims 1 to 6, characterized in that said aqueous solution is heated to a temperature ranging from 20° C. to reflux for a period of time varying from several minutes to several hours, depending on the extraction technique used.

8. The method as claimed in one of claims 1 to 7, characterized in that the ratio between the plant in kilograms and said aqueous solution in liters is between 1:5 and 1:50.

9. The method as claimed in one of claims 1 to 8, characterized in that the extraction is followed by solid-liquid separation by filtration or centrifugation.

10. The method as claimed in one of claims 1 to 9, characterized in that said non-ionic amphiphilic compound is an alkyl polyglycoside of general formula Alk-O-Zp, wherein: Alk denotes a saturated or unsaturated, linear or branched hydrophobic aliphatic hydrocarbon fragment having 3 to 7 carbon atoms, and Z represents a hydrophilic glycoside group such as glucose, xylose and arabinose, and 1<p<5

11. The method as claimed in claim 10, characterized in that the non-ionic amphiphilic compound is a combination of a C.sub.7 fatty alcohol derived from Ricinus and wheat glucose (non-GMO).

12. The method as claimed in claim 10, characterized in that said compound is an amyl glycoside whose hydrophobic amyl fragment corresponds to a C.sub.5 alcohol obtained by fermentation of beet or of potato flour and whose glycoside fragment is derived from cereals.

13. The method as claimed in one of the preceding claims, characterized in that the plant used is selected from the fruits of Physalis peruviana, the fruits of Embelia ribes, the leaves of Myrtus communis, the underground parts and the leaves of Piper spp., the leaves of Eucalyptus globulus, the pericarps of Garcinia mangostana, the female inflorescences of Humulus lupulus, the bark of Cinchona sp., the aerial parts of Urtica dioica, the aerial parts of Helichrysum sp., the fruits of Vanilla sp., the rhizomes of Curcuma spp., the rhizomes of Zingiber officinale and the fruits and the leaves of Olea europaea.

14. The method as claimed in one of claims 9 to 13, characterized in that the solution obtained after solid-liquid separation is preserved as such or is lyophilized, including the molecules of interest, as well as the non-ionic amphiphilic compounds, said non-ionic amphiphilic compounds allowing better solubilization of the extract in the final product.

15. The method as claimed in one of the preceding claims, characterized in that in the extract obtained, the lipophilic compounds are purified by precipitation.

16. Cosmetic and/or pharmaceutical compositions containing total vegetable matrix extract or vegetable matrix extract concentrated in lipophilic compounds obtained by implementation of the method as claimed in one of claims 1 to 15.

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

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

Description

EXAMPLES

Example 1: Enriched Extract of Physalis peruviana

[0082] 100 g of dried and ground Physalis fruit is stirred for 2 h at 40° C. with 700 mL of 1.5 M aqueous heptylglucoside solution (SEPICLEAR G7®, SEPPIC). After filtration, the filtrate is acidified to pH 2 then diluted with 15 volumes of water. After centrifugation, the pellet is taken up and dried. The enriched extract is obtained with a yield of 2.1% by weight.

Example 2: Enriched Extract of Physalis peruviana

[0083] 20 g of dried and ground Physalis fruit is stirred for 2 h at 40° C. with 140 mL of 0.75 M aqueous heptylglucoside solution. After filtration, the filtrate is diluted with 6.6 volumes of water. After centrifugation, the pellet is taken up and dried. The enriched extract is obtained with a yield of 0.64% by weight.

Example 3: Enriched Extract of Physalis peruviana

[0084] 20 g of dried and ground Physalis fruit is stirred for 2 h at 40° C. with 140 mL of 3 M aqueous heptylglucoside solution. After filtration, the filtrate is diluted with 22 volumes of water. After centrifugation, the pellet is taken up and dried. The enriched extract is obtained with a yield of 0.98% by weight.

Results Obtained for the Various Enriched Extracts of Physalis:

[0085]

TABLE-US-00001 Extract Yield Sucrose ester content According to Example 1 2.11% 19.5% According to Example 2 0.64% 16.4% According to Example 3 0.98% 16.2% Ethyl acetate (1 h, reflux) 2.04% 12.9% Heptane (1 h, reflux) 1.04%  3.0%

[0086] In Examples 1 to 3, extraction of Physalis fruits with aqueous heptylglucoside solution followed by precipitation of the extract by dilution produces an extract enriched in sucrose esters. The sugars of the fruit are extracted but remain in solution during the dilution and do not precipitate. The quality of the extracts obtained is superior to the extracts obtained using solvents of petrochemical origin (ethyl acetate, heptane).

Example 4: Vanilla Extract

[0087] 5 kg of dried and ground vanilla pods is extracted for 3 h at 50° C. with 50 L of 1.5 M aqueous heptylglucoside solution. After pressure filtration, the marc is rinsed with 25 L of the same solution. The filtrate is concentrated so as to obtain a vanilla extract in the form of a reddish-brown syrupy solution.

[0088] Results obtained for the vanilla extract:

TABLE-US-00002 Extract Yield Vanillin and derivatives content According to Example 4 800% 0.3%

[0089] This extract, on heptylglucoside substrate, contains a substantial proportion of vanillin and derivatives, while being pre-formulated so as to facilitate its introduction into the aqueous phase of a cosmetic, nutraceutical or medicinal formula.

Example 5: Enriched Extract of Mangosteen

[0090] 100 kg of dried and ground pericarps of Garcinia mangostana is stirred for 2 hours at 40° C. with 1000 L of 1.5 M aqueous heptylglucoside solution. After filtration, the filtrate is acidified to pH=2 then diluted with 11 volumes of water acidified to pH=2. After centrifugation, the pellet is taken up and dried. The extract enriched in xanthones (21.3% expressed in a-mangostin) is obtained with a yield of 7.3% by weight. The extract obtained is tannin-free.

[0091] By comparison, ethanol reflux extraction of dried and ground pericarps of Garcinia mangostana with an identical plant mass/solvent volume ratio gives an extract with a lower xanthone content (19.5% expressed in a-mangostin) but a higher yield (27%). The extract obtained contains tannins.

[0092] By comparison, hexane reflux extraction of dried and ground pericarps of Garcinia mangostana with an identical plant mass/solvent volume ratio gives an extract with a higher xanthone content (89.1% expressed in a-mangostin) but a lower yield (1.2% by weight). The extract obtained is tannin-free.

[0093] Extraction with 1.5 M aqueous heptylglucoside solution thus allows selective extraction of xanthones in comparison with ethanol extraction. It also allows a higher extraction yield than with hexane extraction.

Example 6: Enriched Extract of Piper methysticum

[0094] 1 kg of dried and ground underground parts of Piper methysticum is extracted with 700 mL of 1.5 mol/L aqueous amyl xyloside solution (APXC5) for 1.5 hours under stirring at 40° C. After filtration, the filtrate is diluted with 4 volumes of water. After centrifugation, the pellet corresponding to the enriched extract of Kava is obtained with a yield of 6.2%. The extract contains 3.0% kavalactones.

[0095] By comparison, ethyl acetate reflux extraction of dried and ground underground parts of Piper methysticum with an identical plant mass/solvent volume ratio gives a yield of 8.2%. The extract contains 5.3% kavalactones.

[0096] By comparison, water reflux extraction of dried and ground underground parts of Piper methysticum with an identical plant mass/solvent volume ratio gives a yield of 23.1%. The extract contains 0.25% kavalactones.

[0097] The three extracts have a different kavalactone composition: [0098] The extract obtained by extraction with the 1.5 mol/L aqueous amyl glycoside solution has a higher content of low-polarity kavalactones (yangonin, demethoxyyangonin, flavokavains A, B and C) than the ethyl acetate extract (44.8% compared with 35.3% of total kavalactones). [0099] Conversely, the extract obtained by extraction with the 1.5 mol/L aqueous amyl glycoside solution has a lower content of the most polar kavalactones (methysticin, dihydromethysticin, kavain and marindinin) than the ethyl acetate extract (55.2% compared with 64.7% of total kavalactones). [0100] The extract obtained by aqueous extraction contains 1.66% kavalactones and does not contain low-polarity kavalactones (yangonin, demethoxyyangonin, flavokavains A, B and C).

[0101] Extraction with 1.5 mol/L aqueous amyl glycoside solution thus allows selective extraction of the least polar kavalactones for a total yield comparable to ethyl acetate extraction.

TABLE-US-00003 Example 7: Gelatin capsule Mangosteen extract according to Example 5 200 mg  Starch 45 mg Magnesium stearate  2 mg Example 8: Cream Vanilla extract according to Example 4 0.5-3% Tribehenin PEG- 20 esters .sup. 2-7% Isodecyl neopentanoate .sup. 2-9% Glycerin 0.5-10%  Glycol palmitate .sup. 1-6% Cetyl alcohol 0.5-3% Disodium EDTA 0.05-0.25%    Preservatives 0.5-3% Fragrance 0.2-0.5%.sup.  Xanthan gum 0.1-0.4%.sup.  Water qs

Example 9: Exemplary Solubilization Curves

[0102] The solubilization curves of Sudan red in aqueous solutions of various non-ionic amphiphilic compounds at different concentrations were prepared. After saturation of the solutions with Sudan red and filtration, the Sudan red content solubilized in each solution is measured after dilution by UV spectrophotometry at 476 nm. The solubilization curves appear in the accompanying FIG. 1. The y axis represents OD values multiplied by dilution, these values being proportional to concentration (according to the Beer-Lambert law).

[0103] These curves make it possible to determine the minimum hydrotrope concentration of the non-ionic amphiphilic compounds according to the invention.

[0104] Plantacare (decyl glucoside) is unsuitable, having a clearly surfactant behavior (high solubilization at low concentration, the compound forming micelles). It would be impossible to recover the compounds of interest by dilution. Moreover, the foam formation provided by the surfactant considerably hinders filtration.

[0105] The shape of the curves obtained with a-mangostin according to a similar method (HPLC assay of solubilized a-mangostin) is comparable to those obtained with Sudan red, showing that this value depends on the amphiphilic compound and not on the solute.

[0106] The solubilization curves of a-mangostin in aqueous solutions of non-ionic amphiphilic compounds at various concentrations appear in the accompanying FIG. 2.

[0107] It can thus be deduced from these curves that APXC4 has an MHC of 15-20%, and amyl xyloside of 5-10%.

The MHC of isopentyldiol is between 40 and 45%.

[0108] These values are necessary to implement the extraction method, such as for example the extraction of a-mangostin from mangosteen pericarps:

TABLE-US-00004 g of α-mangostin Compound Concentration extracted % g of plant APX C4  5% 0.36 APX C4 25% 7.87 Isopentyldiol 59% 6.59 Amyl xyloside 40% 7.30 AcOEt 100%  7.49

[0109] At 25% APXC4, the active substance content extracted from mangosteen pericarps is equivalent to that obtained by ethyl acetate reflux extraction, which is not the case at 5% (concentration below the MHC).

[0110] This active substance can then be recovered by dilution when the final concentration of amphiphilic compound is below the MHC, as can be seen in the following table:

TABLE-US-00005 Extraction Concen- % of α-mangostin recovered concen- tration by precipitation/α-mangostin Compound tration after dilution extracted APX C4 25%  9% 86% Isopentyldiol 59% 24% 66% Amyl xyloside 40% 15% 12%  7% 100%  [0111] By diluting the amyl xyloside solution to 15%, little a-mangostin precipitates, the concentration remaining above the MHC. At 7% amyl xyloside, 100% of the a-mangostin extracted precipitates.

Example 10

[0112] Extraction of Fresh Olive Cake

[0113] Weigh 10 g of olive pulp ground after pressing to recover the oil (containing 76% water); add the equivalent of 12 g of APXC4 (dry matter) and water so as to be at a final APXC4 concentration of 50% (taking into account the water content of the plant). Heat for 3 h at 50° C. and filter to recover a clear, brown filtrate with a yield of 87.5%.

[0114] In parallel, lyophilize this same olive pulp (24.5% yield) and extract it with ethyl acetate for 1 h at reflux. After evaporation of the solvent, a cloudy, green oil is obtained with a yield of 23.4% dry matter and 5.7% fresh matter.

[0115] Evaluation of the extracts obtained by TLC under the following conditions: [0116] Stationary phase: TLC plate coated with silica gel 60 [0117] Mobile phase: ethyl acetate/cyclohexane (1:1) [0118] Developer: sulfuric vanillin+heating to 120° C.

[0119] Comparison of the TLC profiles appearing in the accompanying FIG. 3 shows that the extract (LX 1872) with APXC4 contains triterpenes (oleanolic acid and maslinic acid), whereas the AcOEt extract (LX 1874) contains triglycerides in addition to triterpenes. The molecules of interest are thus present without having to dry the material and extract it with a toxic and volatile solvent. Moreover, neither chlorophyll nor neutral lipids are extracted.