Liquid extract from young shoots and / or twigs of Morus alba L. and related topical compositions for the prevention and treatment of skin aging - Patent Application 20070122999

Abstract

A. A plant component complex extracted from young shoots and / or twigs of Morus alba L., containing 25. oxyresveratrol and 26. mulberoside A; B. A liquid extract in which the plant component complex A is dissolved, containing a solvent mixture containing i. 1,3-propanediol, ii. erythritol, and iii. water, wherein I) mixed solvent B) is an extraction solvent; II) the concentration of component a of plant component A is 0.01 to 0.1 wt %, preferably 0.02 to 0.05 wt %, based on the total weight of the liquid extract; and III) the concentration of component b of plant component A is 0.01 to 0.1 wt %, preferably 0.02 to 0.05 wt %, based on the total weight of the liquid extract. a liquid extract having a concentration of 0.007-0.07% by weight, preferably 0.01-0.04% by weight, relative to the total weight of the liquid extract, IV) the weight ratio (i.+ii.) / iii. in solvent mixture B is between 2.00 and 2.50, preferably 2.33, V) the weight ratio i. / ii. in solvent mixture B is between 7.75 and 16.50, preferably 10.66 to 13.00, and VI) the weighted sum of i.+ii.+iii.=100. This extract may be added directly to a composition for cosmetic use having a broad spectrum of anti-aging activity.

Description

[Technical Field]

[0001] The present invention relates to a liquid extract comprising twigs and / or twig phytonutrients complex of Morus alba L., and to a topical composition comprising said extract. [Background technology]

[0002] The genus Morus, belonging to the family Moraceae, consists of over 150 species, of which white mulberry (Morus alba L.) is the dominant species distributed throughout the temperate and subtropical regions of the Northern and Southern Hemispheres. It grows in a wide range of climatic and geomorphological conditions, from mean sea level to an altitude of 4,000 m. The tree grows naturally throughout Asia and is cultivated in China, Korea, Japan, Pakistan, Afghanistan, the northern trans-Indus territory, and the northwestern Himalayas. Various parts of the plant, including the root, fruit, twigs, leaves, and root bark, have been used for centuries in traditional Chinese medicine. (Thomas Pannakal, S, Eilstein, J, Prasad, A, et al., Comprehensive characterization of naturally occurring antioxidants from the twigs of mulberry(Morus alba L.) using on-line high-performance liquid chromatography coupled with chemical detection and high-resolution mass spectrometry.Phytochemical Analysis.2022;33(1):105~114.https: / / doi.org / 10.1002 / pca.3072) Morus alba L. twigs have been widely used in traditional Chinese medicine to treat joint pain and numbness, and have potential health benefits for diabetes, stroke, and cough. Some researchers have studied Morus alba L. twigs and reported their potent inhibitory effects on tyrosinase in humans and mice, as well as on melanin synthesis in B-16 melanoma cells. Morus alba L. twigs contain large reservoirs of secondary metabolites, especially antioxidants, which can be used in the development of skin care products to suppress the development of signs of aging, such as wrinkles and age spots.

[0003] In a study by Hwang et al., it was reported that the ethanol extract of Morus alba L. twigs contains mulberoside A, quercetin, and quercetin-3-O-β-glucoside in addition to the known resveratrol and oxyresveratrol, and furthermore, this extract exhibits high antioxidant activity tested using in vitro assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH).

[0004] Alcoholic extracts of Morus alba L. twigs are also known to contain, among other things, oxyresveratrol. This molecule is well known as a tyrosinase inhibitor and has been described in both food and cosmetic applications for its potential anti-browning effects and as a skin-lightening agent. However, its use in the food and cosmetic industries has not yet been realized due to problems related to its low water solubility, inadequate bioavailability, and poor stability compared to other functional active substances. Recently, several experiments to overcome these problems, such as its encapsulation with cyclodextrins, have been described. (Likhitwitayawuid, K. Oxyresveratrol: Sources, Productions, Biological Activities, Pharmacokinetics, and Delivery Systems. Molecules 2021, 26, 4212. https: / / doi.org / 10.3390 / molecules26144212) In the cosmetic field, there are several examples of extracts of Morus alba L. starting from leaves, roots, and fruits; in particular, almost all extracts currently on the market for cosmetic purposes start with extraction in hydroalcoholic solvents, most often in 70-80% ethanol, followed by a purification step in a chromatographic column. The extracts thus obtained are usually colored powders that must be incorporated into cosmetic formulations and appropriately stabilized.

[0005] International Patent Application WO2020 / 201432 discloses a cosmetic composition containing mulberoside A and mulberoside E, as well as mulberoside F, cis-oxyresveratrol-3'-O-glucopyranoside, trans-oxyresveratrol-3-Ob-glucopyranoside, and oxyresveratrol. These components are obtained by hydroalcoholic extraction (70% ethanol) of twigs and / or young shoots of Morus alba L., followed by a purification step with resin, washing of the resulting liquid extract, and evaporation of the ethanol solvent, resulting in the production of a dry extract. To be used in cosmetic formulations, this dry extract must be appropriately packaged to ensure its stability. The cosmetic composition thus obtained exhibits depigmenting and lightening activity.

[0006] Application US2006 / 0216253 discloses a cosmetic product containing an extract of Morus alba L. with a skin-whitening effect. According to the invention, the extraction of Morus alba L. twigs in powder form is carried out using a 30-100% aqueous solution of ethanol, preferably a 70% aqueous solution. This process results in an extract containing 0.5-5% by weight of oxyresveratrol and 0.5-5% by weight of mulberoside A, based on the total weight of the extract. It is also possible to obtain extracts rich in oxyresveratrol or mulberoside A, as well as purified oxyresveratrol and mulberoside A by a chromatographic column purification process. The purified extract or compound inhibits tyrosinase, an enzyme important in the skin pigmentation process, and can be added to conventional skin care cosmetics to provide depigmenting cosmetics. Again, the resulting dry extract is yellow in color and must be properly brought into the final cosmetic formulation to ensure the stability, and therefore the effectiveness, of the active ingredient claimed in the patent application.

[0007] When performing solvent extraction from plant-based materials, the solvent must meet the following criteria: High selectivity for the target compounds to be extracted ·Safety Ease of separation from the target compound -Good workability ·Low boiling temperature Economical Some of the traditional volatile organic solvents used in plant drug extraction, in order of increasing polarity, include petroleum ether, n-hexane, toluene, diethyl ether, chloroform, dichloromethane, ethyl acetate, acetone, n-butanol, ethanol, and methanol. These solvents are generally used in large quantities, increasing extraction costs, especially when percolation or leaching techniques are used. The use of organic solvents is relatively toxic due to improper extraction procedures and the potential for residual solvent in the resulting extract. Due to their volatility, solvents can become air pollutants that contribute to global warming. The use of alternative, more environmentally friendly solvents is the subject of much scientific research. Summary of the Invention [Means for solving the problem]

[0008] The Applicant has now surprisingly discovered that it is possible to produce a liquid extract, without using organic solvents such as ethanol, starting from twigs and / or young shoots of Morus alba L. In particular, this extract can be used directly in a composition for cosmetic use and contains a complex of phytoconstituents, including oxyresveratrol and mulberoside A.

[0009] The dried and ground plant drug is mixed with a mixture containing cosmetic ingredients that the applicant has discovered can extract oxyresveratrol and mulberoside A from the drug. The ingredients used in the solvent mixture themselves contribute to creating a vehicle that is already stable and suitable for topical cosmetic compositions, thus avoiding the solvent removal step and the generation of processing waste. Thus, an extraction method has been identified that produces a "cosmetic grade," preservative-free liquid extract that corresponds to the raw material of plant origin.

[0010] The liquid extract thus obtained can be directly incorporated into topical compositions, in particular topical compositions for cosmetic use with a broad anti-aging effect. The liquid extract thus obtained can be used in topical formulations for primarily cosmetic use in the prevention and treatment of physiological mechanisms associated with ageing and in skin health.

[0011] Therefore, the object of the present invention is to Aa oxyresveratrol, b. Mulberoside A a plant component complex extracted from twigs and / or young shoots of Morus alba L., comprising: B. Plant component complex A is dissolved, i. 1,3-propanediol ii. Erythritol iii.Water a solvent mixture comprising A liquid extract comprising: I) Mixed solvent B is a solvent extraction; II) the concentration of a. in the plant component complex A is 0.01 to 0.1 wt %, preferably 0.02 to 0.05 wt %, of the total weight of the liquid extract; III) The concentration of b. in the plant component complex A. is 0.007 to 0.07% by weight, preferably 0.01 to 0.04% by weight, of the total weight of the liquid extract A.; IV) the weight ratio (i.+ii.) / iii. in solvent B is 2.00 to 2.50, preferably 2.33; V) the weight ratio i. / ii. in solvent B. is 7.75 to 16.50, preferably 10.66 to 13.00; VI) The weighted sum of i.+ii.+iii.=100, It is a liquid extract. [Brief explanation of the drawings]

[0012] [Figure 1]Figure 1 shows a histogram of oxyresveratrol reduction for extracts T292, T293, T294 and T295, one month after preparation and subjected to the three conditions described in Example 4, Table 7. The values ​​shown on the graph refer to the reduction in % compared to the initial potency of the active ingredient of each prototype. [Figure 2] Figure 1 shows a histogram of the reduction in mulberoside A for extracts T292, T293, T294, and T295, one month after preparation and subjected to the three conditions described in Example 4, Table 7. The values ​​shown on the graph refer to the reduction in % compared to the initial potency of the active ingredient for each prototype. DETAILED DESCRIPTION OF THE INVENTION

[0013] For purposes of the present invention, the definitions "comprise" or "contain" encompass the possibility that additional components may be present in addition to the components stated after this definition. Conversely, for purposes of the present invention, the definition "consisting of" excludes the possibility that additional components may be present in addition to the components listed after the definition.

[0014] For the purposes of the present invention, an extract of Morus alba L. is defined as an extract obtained from the twigs and / or young shoots of said plant. For the purposes of this invention, branches, twigs, and shoots refer to the botanical definitions of these parts of a plant, also called stem-forming branches, and secondary branches are each the part (axis) into which the stem or root of a stem plant divides. Tree branches can be distinguished in terms of primary branches that form a scaffold, and secondary branches that insert into this primary branch, into which twigs two or more years old are embedded, which in turn support shoots (i.e., current-year shoots).

[0015] For this reason, and for the purposes of the present invention, the above-mentioned twigs and shoots fall within the more general classification of tree stems. In view of the above, extracts of shoots and / or twigs may also be defined as stem extracts.

[0016] The term "active ingredient" or "active substance" or "functional active substance" may be defined as any ingredient, molecule, substance, or mixture of compounds capable of stimulating a measurable change in one of the skin parameters being evaluated, where such change is significantly different compared to application of the vehicle alone.

[0017] The term cosmetic carrier refers to a range of excipients that are useful in cosmetic formulations and can affect the skin penetration of active ingredients. However, it should be considered that even a mere "carrier", even one that does not contain an active ingredient, is not a completely inert cosmetic product.

[0018] For purposes of this invention, the term "propanediol" refers to the isomer "1,3 propanediol" as listed in the INCI. The synergistic effect between the vehicle and the active ingredient cannot be predicted in advance and the selection of the correct vehicle guarantees / supports the efficacy and stability of the cosmetic product, especially in the case of active ingredients of plant origin.

[0019] Although most of the technical problems associated with formulating cosmetic products containing active ingredients of plant origin can be overcome by careful selection of raw materials, it is impossible to predict the interactions between the functional active ingredient and the ingredients that make up the carrier (emulsifiers, polymers, oils).

[0020] By the term "cosmetic composition", the Applicant refers to a category of consumer products whose production and sale are subject to specific regulations. In the European Union, and therefore also in Italy, the reference legislation is Regulation (EC) No. 1223 / 2009 of the European Parliament and of the Council of 30 November 2009 on Cosmetic Products. As defined in Article 2 of that Regulation, "cosmetic product" means "any substance or mixture intended to be applied to the external surfaces of the human body (epidermis, hair and hair system, nails, lips, external genitalia), or to the teeth and oral mucosa, with the sole or broad purpose of cleansing them, imparting fragrance to them, modifying their appearance, protecting them, keeping them in good condition, or suppressing body odor."

[0021] Therefore, in order to classify a product as a cosmetic product, ·formulation Application site ·Product function It is essential to consider the following.

[0022] Both the carrier and the incorporation into the formulation of functionally active ingredients that exert a biological, but not a pharmacological, action contribute to the function of the product. These substances are so-called "active ingredients." These ingredients have efficacy "claims," ​​or there are studies supporting the effects of these molecules on biological processes.

[0023] For example, osmoprotectants, small organic molecules that act as osmolytes, concentrate in the cytoplasm, allowing cells to survive under conditions of osmotic stress and maintaining osmotic equilibrium between the intracellular and extracellular environments, belong to this category, exhibiting protective effects on cellular proteins and promoting osmotic balance and vitality of epidermal cells.

[0024] Cells of the same tissue communicate with each other and coordinate their activities through chemical signals sent from cell to cell. By taking advantage of the physiological transmission of intercellular signals, ingredients with osmoprotective properties reach the deepest skin cells and trigger the repair process.

[0025] Cosmetic ingredients that have a hydrating effect work in two different ways. From the outside: reducing transepidermal water loss. Its ingredients are ingredients that create a barrier on the skin surface, such as film-forming agents and emollients, which prevent or reduce evaporation, retain moisture inside and enhance the skin barrier effect.

[0026] From the inside: They contribute to increasing the moisture content inside the epidermis. They are therefore humectants and hygroscopic molecules (capable of absorbing and retaining water), thus helping to increase the amount of moisture present in the skin. Ingredients that are able to exert this effect are also called true moisturizers.

[0027] The term "topical compositions for cosmetic use" for the purposes of the present invention includes various types of products, such as water-in-oil emulsions, oil-in-water emulsions, lotions, gels and oils for the skin, beauty masks, foundations (liquids, pastes, powders), face powders, talc for after-bath and body hygiene, toilet soaps, deodorant soaps, perfumes, eau de toilettes and colognes, bath and shower preparations (salts, foams, oils, gels), hair removal products, deodorants and antiperspirants, hair dyes, waving, straightening and setting products, styling ... means hair-care products, hair-washing products (lotions, powders, shampoos), products for keeping the hairstyle (lotions, creams, oils), hair-styling products (lotions, hairsprays, pomades), shaving products (creams, foams, lotions), make-up and make-up remover products, products intended to be applied to the lips, products for dental and oral hygiene, nail care products and nail lacquers, products for external intimate hygiene, sunscreen products, self-tanning products, products for skin lightening and anti-wrinkle products.

[0028] To prepare plant extracts, FU XII reports that the extracts are prepared by suitable methods using ethanol or other suitable solvents. Suitable excipients can be added during various stages of the manufacturing process to improve the product's technical qualities, such as homogeneity and consistency. Suitable antimicrobial stabilizers and preservatives can also be added. (Capasso F., "Farmacognosia," Chapter 7, pp. 69-72, II, Springer, ed.)

[0029] According to FU XII, p. 833, a liquid extract is "generally a liquid preparation in which one part by weight or one part by volume is equal to one part by weight of dried plant drug or material of animal origin. Such preparations are adjusted, if necessary, to meet the requirements of solvent content and, where appropriate, of the constituents."

[0030] According to the definition of the official Italian Pharmacopoeia, plant drugs are essentially whole, fragmented or cut plants, plant parts, algae, fungi and lichens in an unprocessed state, generally in dried form, but may also be fresh.

[0031] For the purposes of the present invention, the term "phytocomplex" refers to the chemical composition consisting of all the pharmacologically active and non-active substances that exhibit the properties of a medicinal plant itself or a drug, and thus derives its pharmacological and toxicological properties. (Capasso F., "FITOTERAPIA. Impiego razionale delle drogue vegetali", Chapter 20, p. 249, Springer, ed.) For purposes of this invention, the terms "eudermic extraction mixture" and / or "solvent mixture" and / or "extraction mixture" refer to a mixture that corresponds to the extraction solvent in the method for preparing a liquid extract as described above, and that contains at least two cosmetic-grade ingredients that act as a solvent and are capable of extracting molecules / active ingredients from a botanical drug. At the same time, this "eudermic extraction mixture" acts as a carrier for the botanical compound contained therein.

[0032] For the creation of the present invention, the Applicant started from the need to develop an extract starting from twigs and / or twigs of Morus alba L. containing a phytoconstituent complex including two active ingredients such as oxyresveratrol and mulberoside A.

[0033] For initial experiments, the applicant used twigs and / or young shoots of Morus alba L. derived from the prunings (waste wood) of mulberry plants used for sericulture (Gelsibachiculture) located in Northern Italy (Veneto region).

[0034] The liquid extract developed in this invention contains two components, designated A and B. Component A is: a) Oxyresveratrol b) Mulberoside A A plant component complex extracted from the twigs and / or young shoots of Morus alba L., comprising: Component B is a solvent mixture in which the plant component complex A is dissolved, and the solvent B is i. 1,3-propanediol ii. Erythritol iii.Water Including, I. Solvent mixture B. is the extraction solvent, II. The concentration of a. in the plant component complex A is 0.01 to 0.1% by weight, preferably 0.02 to 0.05% by weight, of the total weight of the liquid extract; III. The concentration of b. in the plant component complex A. is 0.007 to 0.07% by weight, preferably 0.01 to 0.04% by weight, of the total weight of the liquid extract; IV. The weight ratio (i.+ii.) / iii. of the solvent mixture B. is 2.00 to 2.50, preferably 2.33; V. The weight ratio i. / ii. of the solvent mixture B. is 7.75 to 16.50, preferably 10.66 to 13.00; VI) The weighted sum is i.+ii.+iii.=100.

[0035] Preferably, the liquid extract according to the invention comprises: the content of water iii. in the solvent mixture B. is 30% by weight of the total weight of said solvents, the concentration of 1,3-propanediol i. in the solvent mixture B. is 62.5-64.5% by weight, based on the total weight of solvent B., and The concentration of erythritol ii. in the solvent mixture B. is 5.5 to 7.5% by weight of the total weight of the solvents. It is characterized by the fact that

[0036] The liquid extract according to the present invention may contain an antioxidant, preferably an antioxidant selected from sodium metabisulfite and glutathione. When the antioxidant is sodium metabisulfite, the concentration of the antioxidant is preferably 0.1 to 0.2% by weight, based on the total weight of solvent B.

[0037] When the antioxidant is glutathione, the concentration of the antioxidant is preferably 0.005 to 0.1% by weight, more preferably 0.01 to 0.05% by weight, based on the total weight of solvent B.

[0038] The liquid extract is prepared from the twigs and / or young shoots of Morus alba L., and the method for preparing the liquid extract comprises the following steps: 1) drying twigs and / or young shoots of Morus alba L. at a temperature of 40°C and to a humidity of less than 10%; 2) grinding and sieving the dried product from step 1 until a homogeneous powder of size 6 mm or less is obtained; 3) At room temperature, the following aspects: 3.1. Mixing erythritol ii. with water iii. until completely dissolved; 3.2. Add 1,3-propanediol under stirring until a clear solution is obtained. preparing a solvent mixture B comprising: 4) Mixing the dried powder obtained in step 2 with the solvent mixture B prepared in step 3 in a weight ratio of dried powder / solvent of 1:8 to 1:12, preferably 1:10, in an ultrasonic bath at room temperature for 1 hour; 5) removing the solid residue resulting from step 4 by at least two passes of vacuum filtration using a filter having pores up to 0.22 microns; Includes:

[0039] The object of the present invention is a topical composition for cosmetic use comprising the liquid extract as defined above, said liquid extract being preferably present in an amount of 1 to 4% by weight relative to the total weight of the cosmetic composition.

[0040] The liquid extract described in the present invention is used for the treatment and prevention of skin aging, in particular for the treatment and prevention of the formation of skin blemishes. The synergistic action of the constituents of the extract makes it possible to obtain a topical skin composition with a broad anti-aging effect, i.e. a product capable of preventing and treating skin aging by acting on the various mechanisms involved in this process.

[0041] By way of illustration, and not an exhaustive list, these mechanisms are collagen degradation, free radical production, inflammation and inflammaging, mechanisms involved in cellular senescence, imprecise intercellular communication due to aging mechanisms, and skin barrier dysfunction.

[0042] In view of the above, the cosmetic composition of the present invention comprises: Morus alba twig and / or shoot extract Propanediol and · Erythritol ii. It can also be interpreted as a cosmetic composition comprising:

[0043] In fact, the water present in the liquid extract of the present invention cannot be distinguished from the water already present in the cosmetic composition when it is in the form of a water-in-oil or oil-in-water emulsion, and for this reason the crucial components present in the final cosmetic composition of the present invention are the extract of Morus alba twigs and / or young shoots, propanediol i. and erythritol ii.

[0044] Therefore, except for the wt% contents, the extract of Morus alba twigs and / or young shoots, propanediol, and erythritol, and the cosmetic composition are as described above, including advantageous and preferred embodiments. According to a particularly preferred embodiment of the cosmetic composition, the content of propanediol i. is 0.59% to 2.69% by weight, preferably 0.620 to 2.58% by weight, and more preferably 0.625 to 2.58% by weight, based on the weight of the cosmetic composition.

[0045] According to another preferred embodiment of this final composition, erythritol ii. is contained in an amount of 0.038 to 0.33 wt. %, preferably 0.055 to 0.32 wt. %, more preferably 0.055 to 0.3 wt. %, based on the weight of the cosmetic composition.

[0046] According to a further preferred embodiment, this cosmetic composition maintains the above-mentioned weight ratio i / ii of the liquid extract of the invention comprised between 7.75 and 16.50, preferably between 10.66 and 13.00.

[0047] The extract of twigs and / or young branches of Morus alba present in this cosmetic composition preferably comprises mulberoside A and oxyresveratrol. Therefore, except for the wt% content, the oxyresveratrol and mulberoside A are as described above, including advantageous and preferred embodiments. Preferably, oxyresveratrol is contained in an amount of 0.0001 to 0.004 wt%, more preferably 0.0002 to 0.002 wt%, based on the weight of the cosmetic composition.

[0048] Preferably, mulberoside A is contained in an amount of 0.00007 to 0.0028% by weight, preferably 0.0001% to 0.0016% by weight, based on the weight of the cosmetic composition.

[0049] The above-reported content ranges of these mulberoside A and oxyresveratrol are easily derived from conditions II) to III) of the liquid extract of the present invention, and also taking into consideration that the liquid extract is contained in the cosmetic composition of the present invention in an amount of 1 to 4 wt % based on the total weight of the cosmetic composition.

[0050] The above compounds are preferably contained in a phytoconstituent complex extracted from the shoots and / or twigs of Morus alba, said phytoconstituent complex being as described above, including advantageous and preferred embodiments.

[0051] In the case of cosmetic compositions having a water content of 0.05% by weight or less before the addition of the liquid extract of the present invention, the significantly higher content of water present in the liquid extract also becomes a decisive component in the final cosmetic composition of the present invention containing the liquid extract of the present invention.

[0052] Thus, the amount of water present in the cosmetic composition of the present invention is preferably at least 0.28 wt. %, more preferably at least 0.30 wt. %, based on the total weight of the cosmetic composition.

[0053] According to a further preferred embodiment of the cosmetic composition of the present invention, the content of water iii. in wt% is at least 0.4 * (i.+ii.), preferably (i.+ii.) / 2.33. The above formula can be easily derived from the above liquid extract condition IV) (i.+ii.) / iii) when it is equal to 2.5 or 2.33.

[0054] All ranges of propanediol, erythritol, and water can be easily derived in consideration of the above conditions of the liquid extract of the present invention. The compositions of the present invention may also contain antioxidants different from mulberoside A and oxyresveratrol, which are as described above, including advantageous and preferred embodiments. The antioxidants may be added, inter alia, to preserve mulberoside A and oxyresveratrol, and are preferably selected from those already mentioned above, namely sodium metabisulfite and glutathione.

[0055] The cosmetic composition described above is preferably in the form of a topical composition as described above.Therefore, it provides the same use as for treating and preventing skin aging, in particular for treating or preventing the formation of skin spots.The following examples are reported below for illustrative purposes, but not for limiting purposes. [Example]

[0056] In order to identify suitable ingredients to constitute a skin-friendly extract mixture suitable for the purposes of the present invention, the applicant has conducted and developed a variety of systematic extractions. For each system, the applicant applied the following process.

[0057] 1. Crushing of plant drug (twigs and / or young shoots of Morus alba L.) 2. Preparation of the extract mixture (solvent) that is good for the skin 3. Extraction: The plant drug was contacted with a skin-friendly extract / solvent mixture in a ratio of 1:10 (w / w) and extracted in an ultrasonic bath at room temperature (25°C) for 1 hour.

[0058] 4. Extract Filtration: The depleted plant drug is separated from the extraction solvent mixture by vacuum microfiltration using a Buchner funnel with a filter having pores down to 0.22 microns. This filtration method is well known to those skilled in the art.

[0059] The liquid extract target of the present invention corresponds to the liquid that is filtered in the final filtration step. Steps 1 and 2, which are relevant for patent purposes, are described in detail below. Steps 3 and 4 are well known to those skilled in the art.

[0060] Step 1 – Preparing the plant drug for extraction The liquid extract of the present invention can be prepared starting from twigs and / or young shoots of Morus alba L. The process of preparing the plant drug requires a first step in which the twigs and / or young shoots are dried in an oven (air dryer) at a temperature of 40° C. until the humidity is less than 10%.

[0061] The dried botanical drug substance is then milled using a knife mill to obtain a powder with a maximum particle size of 6 mm or less, preferably 1 mm or less, which is achieved by sieving the dried and milled botanical drug substance through a sieve with a mesh size of 6 mm to 1 mm (which rejects powder larger than these dimensions).

[0062] Various extraction tests, defined as "systematic extraction," were performed on the plant drug thus obtained by contacting it with a mixture of various ingredients, which are listed in Table 2.

[0063] Step 2 - Preparing the Extraction Solvent Mixture The first systematic extraction served to investigate whether it was possible to combine two ingredients of common cosmetic use to produce a mixture that could act as an alternative solvent to a 70% ethanol in water mixture. In fact, ethanol is known from the literature to be a good solvent for extracting compounds such as oxyresveratrol and mulberoside A from Morus alba L. plant material.

[0064] The ingredients shown in Table 1 were also selected for their synergistic effects, acting together with the active ingredients extracted from the plants, to produce extracts for cosmetic use with broad-spectrum anti-aging "claims."

[0065] For each ingredient, the amounts used are shown in Table 2. Example 1: Identification of Carrier / Solvent Components The first systematic experiment served to identify components that could constitute an extract mixture, each of which could meet the following characteristics:

[0066] - A good carrier: i.e. an ingredient with functional "appeal" for cosmetic use. This step is particularly important because the applicant wanted to produce an extract in which the solvent mixture itself acts as a vehicle for the final extract. Therefore, compared to the prior art, no further steps are required after the extraction process to eliminate / remove the solvent or to purify the extract so that it is free of any impurities.

[0067] It can exert a solvent effect, but at the same time it is a skin-friendly / suitable for cutaneous application and is a non-irritating ingredient. A "ready to use" extract is produced to be included in a formulation for cosmetic use, where the following is evaluated:

[0068] Physical state, which must be liquid or water-soluble powder ·Physicochemical stability, ·color, ·viscosity, The ability to protect the liquid extract from microbial contamination. This last aspect is crucial, since aqueous extracts are more exposed to chemical degradation processes and microbial contamination of the extracted active ingredients than dry extracts.

[0069] · Cost of raw materials. The formulation designer / applicant's selection was directed to raw materials containing at least one hydroxyl group, such as commercially available alcohols or polyols. 1,3-propanediol was chosen for its preservative function and its low viscosity, which facilitates filtration. A list of the ingredients tested is shown in Table 1.

[0070] [Table 1]

[0071] Example 2: Extraction tests using various mixtures of the ingredients in Table 1 to identify the most suitable solvent mixture for the purposes of the present invention For extraction, the plant drug is mixed with the extraction mixture in a ratio of 1:10 (w / w) and extracted in an ultrasonic bath at room temperature (25° C.) for 1 hour.

[0072] Table 2 shows the extract mixtures tested: for each extract, microbiological analysis and titration of the active substances of interest (oxyresveratrol and mulberoside A) were performed. For microbiological analysis, analytical tests were carried out according to standard protocols known to those skilled in the art: ISO21148:2017, in particular ISO21149:2017 for total bacterial load, and ISO16212:201 for yeast and mold. For the counting of cultured bacteria, yeast and mold, TSA medium and SDA medium (TSA = tryptic soy agar; SDA = Sabouraud dextrose agar) are used. Microbial count values ​​in TSA / SDA medium are considered acceptable for numbers <10 cfu / ml (cfu = colony forming units).

[0073] The titration of the active substance was carried out by HPLC-UV DAD. One gram of biomass was weighed into 50 ml of 80:20 methanol / water and sonicated for 40 minutes. The solution was then centrifuged and placed in an analytical vial. Analysis was performed on an HPLC-DAD using a Phenomenex Synergy RP MAX column as the stationary phase and methanol and water containing 0.1% formic acid as the mobile phase.

[0074] The stilbenoid oxyresveratrol and its glycosylated derivative mulberoside A (Sigma-Aldrich) were used as reference standards. Readings were taken at 330 nm.

[0075] The T209 extract is the "gold standard" reference for 70% ethanol extraction as disclosed in WO2020 / 201432.

[0076] [Table 2]

[0077] Completely unexpectedly, the applicant discovered that the combined potency of the two active ingredients in the extracts of T244 to T290 was higher or comparable to that of the ethanol extract. From this systematic extraction, the most promising prototypes in terms of potency of the two active ingredients of interest were T244 and T290.

[0078] This systematic extraction was also used to evaluate the stability of the prototype at T=5° C. and at room temperature (25° C.), which was carried out over a 6-month period (Table 3).

[0079] [Table 3]

[0080] From these systematic experiments, prototypes T244 to T290 were selected as those that demonstrated good dissolving power (intended for higher concentrations of the desired active substance) and good stability at the temperature conditions tested.

[0081] Table 4 shows the prototypes that were selected for subsequent systematic experiments.

[0082] [Table 4]

[0083] Example 3: Sensory stability check of selected prototypes after 1 month To assess the sensory stability of selected extracts after one month, a systematic study was set up in which each extract was subjected to stress conditions: Refrigerator (5℃) / dark place Room temperature (25°C) / bright place Oven (40℃) / dark place It was decided.

[0084] In particular, each prototype was analyzed for color and appearance: a shift in the solution to a darker color, the presence of any precipitate or turbidity indicates instability of the system. The results are reported in Table 5.

[0085] [Table 5]

[0086] Under all conditions tested, none of the extracts tested showed precipitation or turbidity at the 4-week time point. Both extracts showed slight darkening in the light and in the oven, but no color change in the dark at 5°C. Example 4: Stability test with the addition of antioxidants Based on the stability data for the T244 and T290 extracts, four different antioxidant systems were tested to preserve the active ingredients of the botanical complex, oxyresveratrol and mulberoside A, and to prevent browning of the liquid extract under the conditions tested in Table 5 where a color change was detected.

[0087] Two antioxidants were chosen: sodium metabisulfite and glutathione. Table 6 shows the prototypes tested and the conditions under which they were tested.

[0088] [Table 6]

[0089] [Table 7]

[0090] Figures 1 and 2 show histograms of the reduction in oxyresveratrol (Figure 1) and mulberoside A (Figure 2) for extracts T292, T293, T294 and T295 one month after preparation and subjected to the three conditions described in Example 4, Table 7. The values ​​shown on the graphs refer to the reduction in % compared to the initial potency of the active ingredient of each prototype.

[0091] The advantage of using a mixture of well-known ingredients as a solvent in cosmetic formulations is that an extract is obtained that does not require an additional purification step to eliminate the extraction solvent, because the extract mixture is a skin-friendly mixture that cooperates with the functionality and microbiological stability of the extract itself. To the applicant's knowledge, there are no other ready-to-use formulations containing a plant ingredient complex including oxyresveratrol and mulberoside A that are stable from a microbiological and organoleptic point of view.

[0092] The extracts thus obtained can be used in the prevention and treatment of physiological mechanisms associated with ageing, as well as in cosmetic formulations for skin health. Below are some example formulations for illustrative purposes and not for limiting purposes. [Table A] [Table B] [Table C]

Claims

1. A. a. oxyresveratrol, b. Mulberoside A a phytoconstituent complex extracted from young shoots and / or twigs of Morus alba L., comprising: B. The botanical composite A is dissolved; i. 1,3-propanediol ii. Erythritol iii. water a solvent mixture comprising A liquid extract comprising: I. The mixed solvent B) is an extraction solvent, II. The concentration of a. of the plant component complex A is comprised between 0.01 and 0.1% by weight, preferably between 0.02 and 0.05% by weight, based on the total weight of the liquid extract; III. The concentration of b. in the plant component complex A. is comprised between 0.007 and 0.07% by weight, preferably between 0.01 and 0.04% by weight, based on the total weight of the liquid extract; IV. The weight ratio (i. + ii.) / iii. in the solvent mixture B. is comprised between 2.00 and 2.50, preferably 2.33; V. the weight ratio i. / ii. in said solvent mixture B. is comprised between 7.75 and 16.50, preferably between 10.66 and 13.00; VI. i. + ii. + iii. = 100, liquid extract.

2. the content of water iii. in said solvent mixture B. is 30% by weight relative to the total weight of said solvents, the concentration of 1,3-propanediol i. in the solvent mixture B. is comprised between 62.5 and 64.5% by weight relative to the total weight of the solvent B., and ii. the concentration of erythritol in said solvent mixture B is comprised between 5.5 and 7.5% by weight of the total weight of said solvents; The liquid extract of claim 1.

3. 3. The liquid extract of claim 2, wherein said solvent mixture B. comprises antioxidants.

4. 4. The liquid extract of claim 3, wherein the antioxidant is selected from sodium metabisulfite and glutathione.

5. 5. The liquid extract according to claim 4, wherein when the antioxidant is sodium metabisulfite, the concentration of the antioxidant is comprised between 0.1 and 0.2% by weight relative to the total weight of the solvent mixture B.

6. 5. The liquid extract according to claim 4, wherein when said antioxidant is glutathione, the concentration of said antioxidant is comprised between 0.005 and 0.1% by weight, preferably between 0.01 and 0.05% by weight, relative to the total weight of said solvent mixture B.

7. Steps below:

1. Drying young shoots and / or twigs of Morus alba L. at a temperature equal to 40° C. and to a humidity of less than 10%; 2. Milling and sieving the dried product from step 1 until a homogenous powder of 6 mm or less in size is obtained; 3. At room temperature, perform the following steps: 3.

1. Mixing erythritol ii. with water iii. until completely dissolved; 3.

2. Adding 1,3-propanediol under stirring until a clear solution is obtained. Preparing the solvent mixture B. comprising:

4. Mixing the dried powder obtained in step 2 with the solvent mixture B prepared in step 3 in a weight ratio of dried powder / solvent mixture B of 1:8 to 1:12, preferably 1:10, in an ultrasonic bath at room temperature for 1 hour; 5. Removing the solid residue from step 4 by at least two passes of suction filtration using a filter with pores up to 0.22 microns; 7. A method for preparing a liquid extract according to any one of claims 1 to 6, comprising:

8. A cosmetic topical composition comprising a liquid extract according to any one of claims 1 to 6.

9. 9. The cosmetic topical composition according to claim 8, wherein said liquid extract is present in an amount comprised between 1 and 4% by weight relative to the total weight of the composition.

10. 7. A liquid extract according to any one of claims 1 to 6 for use in the treatment and prevention of skin ageing.

11. 11. A liquid extract for use according to claim 10 for treating and preventing the formation of skin spots.

12. 10. Cosmetic use of a liquid extract according to any one of claims 1 to 6 for treating and preventing skin ageing.

13. extract of twigs and / or young shoots of Morus alba, propanediol i, and Erythritol ii. A cosmetic composition comprising:

14. The cosmetic composition according to claim 13, wherein the content of propanediol i. is 0.59% to 2.69% by weight, preferably 0.620 to 2.58% by weight, more preferably 0.625 to 2.58% by weight, based on the weight of the cosmetic composition.

15. The cosmetic composition according to claim 13 or 14, wherein the content of erythritol (ii) is 0.038 to 0.33 wt %, preferably 0.055 to 0.32 wt %, more preferably 0.055 to 0.3 wt %, relative to the weight of the cosmetic composition.

16. The cosmetic composition according to any one of claims 13 to 15, wherein the weight ratio (i) / (ii) is comprised between 7.75 and 16.50, preferably between 10.66 and 13.

00.

17. 17. The cosmetic composition according to any one of claims 13 to 16, wherein the extract of twigs and / or young shoots comprises mulberoside A and oxyresveratrol.

18. The cosmetic composition according to claim 17, wherein the oxyresveratrol is contained in an amount of 0.0001 to 0.004 wt %, preferably 0.0002 to 0.002 wt %, based on the weight of the cosmetic composition.

19. The cosmetic composition according to claim 17 or 18, wherein the mulberoside A is contained in an amount of 0.00007 to 0.0028% by weight, preferably 0.0001% to 0.0016% by weight, based on the weight of the cosmetic composition.

20. 20. The cosmetic composition of claim 17, wherein the mulberoside A and the oxyresveratrol are contained in a botanical complex extracted from young shoots and / or twigs of Morus alba.

21. 21. The cosmetic composition according to any one of claims 13 to 20, comprising water (iii) and optionally an antioxidant.

22. 22. The cosmetic composition of claim 21, wherein the amount of water is at least 0.28 wt. %, preferably at least 0.30 wt. %, based on the total weight of the cosmetic composition.

23. The water content is at least 0.4% by weight based on the total weight of the composition. ＊ 23. The cosmetic composition according to claim 21 or 22, wherein [(i) + (ii)], preferably [(i) + (ii)] / 2.

33.

24. 24. The cosmetic composition of any one of claims 13 to 23, which is a topical cosmetic composition.

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