Liquid extract of branchlet and / or twig of white mulberry and related topical composition for prevention and treatment of skin aging

Abstract

A liquid extract comprising: A. a plant complex extracted from branchlet and / or branchlet of white mulberry, the plant complex comprising 1. Oxyresveratrol, 2. Mulberroside AB, a solvent mixture in which the plant complex A is dissolved, the mixture comprising: i. 1, 3-propylene glycol, ii. Erythritol, iii. Water, where i. 1, 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, i. 3-propylene glycol, and i. 3-propylene glycol; i) mixed solvent B) for extraction solvent II) the concentration of a. Of the plant complex A is between 0.01 wt% and 0.1 wt%, preferably between 0.02 wt% and 0.05 wt%, based on the total weight of the liquid extract III) the concentration of b. Of the plant complex A is between 0.007 wt% and 0.07 wt%, based on the total weight of the liquid extract, preferably between 0.01 wt% and 0.05 wt%, based on the total weight of the liquid extract III) the concentration of b. Of the plant complex A is between 0.01 wt% and 0.1 wt%, preferably between 0.02 wt% and 0.05 wt%, based on the total weight of the liquid extract. The invention relates to an extract for cosmetic use, preferably between 0.01% by weight and 0.04% by weight, IV) the weight ratio of solvent mixture B (i. + i.) / i. Is comprised between 2.00 and 2.50, preferably 2.33, V) the weight ratio of solvent mixture B (i. / ii. Is comprised between 7.75 and 16.50, preferably it is comprised between 10.66 and 13.00, VI) the total weight of i. + i. + i. Is equal to 100, which can be added as such to a composition for cosmetic use with comprehensive anti-aging activity.

Description

Technical Field

[0001] The present invention relates to a liquid extract of a phytocomplex comprising twigs and / or twigs of white mulberry (Morus alba L.) and a topical composition comprising the extract. Background Art

[0002] The genus Morus belongs to the Moraceae family and consists of more than 150 species, and among these, the white mulberry (Morus alba L.) is the predominant species distributed in temperate and subtropical regions of the Northern and Southern Hemispheres. It grows in a wide range of climatic and topographical conditions, from mean sea level to altitudes as high as 4,000 m. The tree grows naturally throughout Asia and is cultivated in China, Korea, Japan, Pakistan, Afghanistan, the northern Trans-Indus region, and the northwestern Himalayan region. Various parts of the plant, including roots, fruits, twigs, leaves, and root bark, have been used in traditional Chinese medicine for centuries. (Thomas Pannakal, S, Eilstein, J, Prasad, A, et al. Comprehensive characterization of naturally occurring antioxidants from the twigs ofmulberry (Morus alba L.) using on-line high-performance liquid chromatography coupled with chemical detection and high-resolution massspectrometry. Phytochemical Analysis. 2022; 33(1): 105-114. https: / / doi.org / 10.1002 / pca.3072 )

[0003] White mulberry twigs have been widely used in Eastern medicine to treat joint pain and numbness and have potential health benefits against diabetes, stroke, and cough. Several researchers have studied white mulberry twigs and reported their potent inhibitory effects on human and mouse tyrosinase and melanin synthesis in B-16 cell melanoma. White mulberry twigs contain a large number of secondary metabolites, particularly antioxidants, which can be used in cosmetics to develop skin care products and combat the appearance of signs of aging, such as wrinkles and discoloration.

[0004] In a study by Hwang et al., an ethanol extract of white mulberry twigs was reported to contain morusin A, quercetin, and quercetin-3-O-β-glucoside in addition to the known resveratrol and oxyresveratrol; in addition, the extract showed high antioxidant activity tested using in vitro assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH).

[0005] It is also known that ethanol extracts of white mulberry twigs contain, in particular, oxidized resveratrol: this molecule is well known in both food and cosmetics as a tyrosinase inhibitor and has been described for its potent anti-browning effect and potential as a skin whitening agent. However, its application in the food and cosmetics industries has not yet been realized due to problems related to its low solubility in water, poor bioavailability, and low stability compared to other functional active substances. In recent years, several experiments have been described to overcome these problems, such as encapsulation with cyclodextrins. (Likhitwitayawuid, K. Oxyresveratrol: Sources, Productions, Biological Activities, Pharmacokinetics, and Delivery Systems. Molecules 2021, 26, 4212. https: / / doi.org / 10.3390 / molecules26144212 )

[0006] In the cosmetics sector, there are several examples of extracts of white mulberry from leaves, roots and fruits, and in particular, almost all the extracts currently on the market for cosmetic purposes are obtained starting from an extraction in a hydroalcoholic solvent, more often 70-80% ethanol, followed by a purification step in a chromatographic column. The extracts thus obtained are usually a colored powder that must be carried in a cosmetic formulation and suitably stabilized.

[0007] International patent application WO2020 / 201432 discloses a cosmetic composition comprising mulberry glycoside A and mulberry glycoside E, as well as mulberry glycoside F, cis-oxidized resveratrol-3'-O-glucopyranoside, trans-oxidized resveratrol-3-O-β-glucopyranoside, and oxidized resveratrol. These components are obtained by hydroalcoholic extraction (70% ethanol) of twigs and / or twigs of white mulberry, which results in the production of a dry extract after a purification step on the resin, washing the obtained liquid extract, and evaporating the ethanol solvent. In order to be used in cosmetic formulations, the dry extract must be properly carried to ensure its stability. The cosmetic composition thus obtained is indicated for depigmentation and whitening activities.

[0008] Application US2006 / 0216253 discloses a cosmetic product containing a white mulberry extract with a whitening effect. According to this invention, powdered white mulberry twigs are extracted with a 30-100%, preferably 70%, aqueous ethanol solution. This method provides an extract containing 0.5-5% by weight of oxidized resveratrol and 0.5-5% by weight of morusin A, based on the total weight of the extract. Extracts enriched in oxidized resveratrol or morusin A, as well as purified oxidized resveratrol and morusin A, can also be obtained through chromatographic column purification. These purified extracts or compounds can be added to conventional skin care cosmetics to provide depigmenting cosmetics, as they inhibit tyrosinase, a key enzyme in the skin pigmentation process. However, the resulting dried extract is yellow in color and must be properly incorporated into the final cosmetic formulation to ensure the stability and, therefore, effectiveness of the active ingredients claimed in this patent application.

[0009] When solvent extraction is performed from plant-based materials, the solvent must meet the following criteria:

[0010] High selectivity for the target compounds to be extracted

[0011] Security

[0012] Easy to separate from target compounds

[0013] Good machinability

[0014] Low boiling temperature

[0015] Economical

[0016] Some traditional volatile organic solvents used in the extraction of botanicals include, in order of increasing polarity, petroleum ether, n-hexane, toluene, diethyl ether, chloroform, dichloromethane, ethyl acetate, acetone, n-butanol, ethanol, and methanol. Generally, these solvents are used in large quantities, especially when performing maceration or soaking, which increases the cost of extraction. The use of organic solvents is relatively toxic due to improper extraction procedures and the potential for residual solvents in the resulting extract. The volatility of the solvents makes them potential air pollutants that contribute to global warming. The use of alternative and green solvents is the subject of much scientific research. Summary of the Invention

[0017] The applicant has now surprisingly found that it is possible to produce a liquid extract from twigs and / or twigs of white mulberry without using organic solvents such as ethanol. In particular, the extract can be used directly in a composition for cosmetic use and includes a phytocomplex containing oxyresveratrol and morusin A.

[0018] The dried and ground herb was mixed with a mixture containing cosmetic ingredients, which the applicants discovered was capable of extracting oxyresveratrol and morusin A from the herb. The ingredients used in the solvent mixture themselves helped create a stable and suitable vehicle for topical cosmetic compositions, thereby avoiding solvent removal steps and the generation of processing waste. Consequently, the extraction process was confirmed to produce a preservative-free liquid extract comparable to "cosmetic-grade" botanical raw materials.

[0019] The liquid extract thus obtained can be added as such to topical compositions, in particular for cosmetic use with an overall anti-aging effect.

[0020] The liquid extract thus obtained can be used in topical formulations, primarily cosmetic, for the prevention and treatment of physiological mechanisms related to aging and skin health.

[0021] The object of the present invention is therefore a liquid extract comprising:

[0022] A. A phytocomplex extracted from twigs and / or twigs of white mulberry, the phytocomplex comprising:

[0023] a. Oxidized resveratrol,

[0024] b. Mulberry glycoside A

[0025] B. A solvent mixture in which the plant complex A is dissolved, said mixture comprising:

[0026] i.1,3-Propanediol

[0027] ii. Erythritol

[0028] iii. Water

[0029] in:

[0030] 1) mixed solvent B is an extraction solvent,

[0031] II) the concentration of a. of the phytocomplex A is 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,

[0032] III) the concentration of b. of the phytocomplex A is between 0.007% and 0.07%, preferably between 0.01% and 0.04% by weight of the total weight of the liquid extract,

[0033] IV) the weight ratio (i.+ii.) / iii. in solvent B. is between 2.00 and 2.50, preferably it is 2.33,

[0034] V) the weight ratio i. / ii. in solvent B. is between 7.75 and 16.50, preferably between 10.66 and 13.00;

[0035] VI) The total weight of i.+ii.+iii.=100. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Shown are histograms relating to the decrease in oxidized resveratrol of extracts T292, T293, T294 and T295 one month after preparation and subjected to the three conditions described in Table 7 of Example 4. The values ​​shown in the graph refer to the % decrease compared to the initial titer of the active ingredient of each prototype.

[0037] Figure 2 Shown are histograms relating to the decrease in Mulberoside A of the extracts of T292, T293, T294 and T295 one month after preparation and subjected to the three conditions described in Table 7 of Example 4. The values ​​shown in the graph refer to the % decrease compared to the initial titer of the active ingredient of each prototype. DETAILED DESCRIPTION

[0038] For the purposes of the present invention, the definition "comprising" or "containing" encompasses the possibility that further components are present in addition to those mentioned after the definition.

[0039] On the contrary, for the purposes of the present invention, the definitions "consisting of" do not include the possibility that further components are present than those listed after these definitions.

[0040] For the purposes of the present invention, an extract of white mulberry is defined as an extract obtained from the twigs and / or twigs of said plant.

[0041] For the purposes of the present invention, branches, twigs and twigs refer to the botanical definitions of these parts of a plant, also known as branches forming the stem, and secondary branches are each of the parts (axes) into which the stem or root of a stem-leaved plant is divided; branches can be distinguished into main branches, which form a support, and secondary branches, which are inserted into the main branches and on which twigs of two or more years are implanted, which in turn carry twigs (i.e., branches of that year).

[0042] For this reason and for the purposes of the present invention, the above twigs and twigs fall under the more general classification of tree stems.In view of the above, twig and / or twig extracts may also be defined as stem extracts.

[0043] The term "active ingredient" or "active" or "functional active" can be defined as any ingredient, molecule, substance or mixture of compounds that is capable of measurably stimulating a change in one of the skin parameters being evaluated, wherein the change is significantly different compared to application of vehicle alone.

[0044] The term cosmetic carrier refers to a range of excipients that aid in the formulation of cosmetic products and can influence the skin penetration of active ingredients.

[0045] However, it should be considered that even simple "carriers", despite being devoid of active ingredients, are not completely inert cosmetic products.

[0046] For the purposes of the present invention, with the expression "propylene glycol" we mean the isomer "1,3-propanediol" listed in INCI.

[0047] The synergistic effect between vehicle and active ingredient cannot be predicted in advance and the selection of a suitable vehicle guarantees / supports the effectiveness and stability of the cosmetic product, especially in the case of active ingredients of plant origin.

[0048] Most of the technical problems associated with the formulation of cosmetic products containing active ingredients of plant origin can be overcome by careful selection of raw materials, but it is impossible to predict the interactions between the functional active ingredients and the components constituting the vehicle (emulsifiers, polymers, oils).

[0049] 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 law 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 this Regulation, a "cosmetic product" is: "any substance or mixture intended for application to the external surfaces of the human body (the epidermis, the hair and hair system, the nails, the lips, the external genitalia), or to the teeth and the mucous membranes of the mouth, with the sole or main purpose of cleansing them, scenting them, improving their appearance, protecting them, keeping them in good condition or correcting body odours".

[0050] Therefore, in order to classify a product as a cosmetic product, one must consider:

[0051] ·formula,

[0052] Application site,

[0053] Product features.

[0054] Both carriers and the inclusion of functional active ingredients in the formulation that perform biological, but non-pharmacological, actions contribute to product function. These substances are referred to as "active ingredients." These ingredients have a "claim" for efficacy, or there are studies supporting the effects of these molecules on biological processes.

[0055] For example, osmoprotectants belong to this category: small organic molecules that act as osmolytes and concentrate themselves in the cytoplasm, allowing cells to survive under conditions of osmotic stress and maintaining the osmotic balance between the intracellular and extracellular environments. They exhibit a protective effect on cellular proteins and promote osmotic balance and vitality of epidermal cells.

[0056] Cells of the same tissue communicate with each other through chemical signals sent from cell to cell to coordinate their activities. Ingredients with osmotic protection claims reach the deepest skin cells by utilizing the physiological transmission of cell-to-cell signals and triggering the repair process.

[0057] Cosmetic ingredients that have hydrating properties work in two different ways:

[0058] Externally: Reduce transepidermal water loss. These are ingredients that form a barrier on the skin surface, such as film-forming agents and emollients, which prevent or reduce sweating, retain moisture inside, and strengthen the skin barrier effect.

[0059] From the inside: They help increase the water content within the epidermis. They are therefore humectants and hygroscopic molecules (capable of attracting and retaining water), thereby helping to increase the amount of water present in the skin. Ingredients that can exhibit this effect are also known as true humectants.

[0060] For the purposes of the present invention, the term "topical composition for cosmetic use" refers to various types of products, such as: water-in-oil emulsions, oil-in-water emulsions, lotions, gels and oils for skin application, cosmetic masks, foundations (liquids, creams, powders), face powders, after-shower talcum powders and body hygiene products, cosmetic soaps, deodorant soaps, perfumes, toilet waters and colognes, bathroom and shower preparations (salts, foams, oils, gels), depilatory products, deodorants and antiperspirants, hair dyes, hair straightening products, styling products, hair cleansing products (lotions, powders, shampoos), products for maintaining the hair in a defined shape (lotions, creams, oils), hair styling products (lotions, sprays, pomades), shaving products (creams, foams, lotions), make-up and make-up removal products, products intended for application to the lips, products for dental and oral hygiene, nail care products and nail polishes, products for external intimate area hygiene, sun protection products, tanning products, products for lightening the skin and anti-wrinkle products.

[0061] To produce plant extracts, FU XII reports that the extracts are prepared by a suitable method using ethanol or other suitable solvents. Suitable excipients can be added at various stages of the production process, for example to improve the product's process qualities, such as homogeneity and consistency. Suitable antimicrobial stabilizers and preservatives may also be added. (Capasso F. "Farmacognosia," chap. 7, pp. 69-72; II ed. Springer).

[0062] Liquid extracts, according to FU XII, page 833, "are liquid preparations in which, generally speaking, one part by mass or volume is equivalent to one part by mass of the dry herbal or animal-derived material. These preparations are adjusted, if necessary, to meet the requirements for solvent content and, where appropriate, composition."

[0063] According to the Italian official pharmacopoeia, herbal medicines are essentially whole, broken or cut plants, plant parts, algae, fungi, lichens, in an unprocessed state, usually in dried form, but sometimes fresh.

[0064] For the purposes of the present invention, the term "phytocomplex" is composed of all those pharmacologically active or non-pharmacologically active substances which characterize the medicinal plant itself or the medicinal material and thus represent its chemical composition, from which the pharmacological and toxicological properties are derived (Capasso F. "FITOTERAPIA. Impiego razionaledelledroghe vegetali" cap. 20, page 249; Springer ed.).

[0065] For the purposes of the present invention, the term "eudermic extract mixture" and / or "solvent mixture" and / or "extraction mixture" refers to a mixture that is comparable to the extraction solvent used in the process for preparing liquid extracts (such as described above) and contains at least two cosmetic-grade ingredients capable of acting as solvents and extracting molecules / active ingredients from the herbal medicine. At the same time, this "eudermic extract mixture" acts as a carrier for the botanical complex contained therein.

[0066] For the development of the present invention, the applicant started from the need to develop an extract from twigs and / or twigs of Morus alba containing a phytocomplex comprising two active ingredients such as oxyresveratrol and morusin A.

[0067] For the initial experiments, the applicant used twigs and / or twigs of Morus alba obtained from cuttings (waste) of Gelsibachiculture plants located in northern Italy (Veneto region).

[0068] The liquid extract developed by the present invention comprises two components, designated A and B. Component A is a phytocomplex extracted from twigs and / or twigs of white mulberry, comprising:

[0069] a) Oxidized resveratrol

[0070] b) Mulberinoside A

[0071] Component B is a solvent mixture in which the above-mentioned plant complex A is dissolved, and the solvent B comprises:

[0072] i.1,3-Propanediol

[0073] ii. Erythritol

[0074] iii. Water

[0075] in:

[0076] I. Solvent mixture B is the extraction solvent

[0077] II. The concentration of a. of the plant complex A is between 0.01% and 0.1%, preferably between 0.02% and 0.05% by weight of the total weight of the liquid extract

[0078] III. The concentration of b. of the plant complex A is between 0.007% and 0.07%, preferably between 0.01% and 0.04% by weight of the total weight of the liquid extract

[0079] IV. The weight ratio of solvent mixture B (i.+ii.) / iii. is between 2.00 and 2.50, preferably 2.33,

[0080] V. a weight ratio i. / ii. of solvent mixture B between 7.75 and 16.50, preferably between 10.66 and 13.00;

[0081] VI) The total weight of i.+ii.+iii.=100.

[0082] Preferably, the liquid extract described in the present invention is characterized by the following facts:

[0083] · the water content in solvent mixture B iii. is 30% by weight based on the total weight of the solvents;

[0084] The concentration of 1,3-propylene glycol i. in solvent mixture B is between 62.5% and 64.5% by weight, based on the total weight of solvent B;

[0085] • The concentration of erythritol ii. in solvent mixture B is between 5.5% and 7.5% by weight of the total weight of said solvent.

[0086] The liquid extract according to the invention can contain an antioxidant, preferably chosen between sodium metabisulfite and glutathione.

[0087] When the antioxidant is sodium metabisulfite, the concentration of the antioxidant is preferably between 0.1 wt% and 0.2 wt% based on the total weight of solvent B.

[0088] When the antioxidant is glutathione, the concentration of the antioxidant is preferably between 0.005 wt% and 0.1 wt%, more preferably between 0.01 wt% and 0.05 wt%, based on the total weight of solvent B.

[0089] A liquid extract is prepared from twigs and / or twigs of white mulberry, and the process for preparing the liquid extract comprises the following stages:

[0090] 1) Dry the twigs and / or twigs of white mulberry at a temperature of 40°C and until the humidity is less than 10%

[0091] 2) Grind and sieve the dried product from stage 1 until a homogeneous powder with a size less than or equal to 6 mm is obtained

[0092] 3) Preparation of solvent mixture B, which comprises the following stages at room temperature:

[0093] 3.1. Mix erythritol ii. with water iii. until completely dissolved.

[0094] 3.2. Add 1,3-propylene glycol with stirring until a clear solution is obtained;

[0095] 4) mixing the dry powder obtained in stage 2 with the solvent mixture B prepared in stage 3 in a dry powder / solvent weight ratio between 1:8 and 1:12, preferably 1:10, in an ultrasonic bath at room temperature for 1 hour;

[0096] 5) Remove the solid residue from stage 4 by vacuum filtration at least twice using filters with pore sizes up to 0.22 microns.

[0097] The object of the present invention is a topical composition for cosmetic use comprising a liquid extract as described above, wherein said liquid extract is present in an amount between 1% and 4% by weight relative to the total weight of the cosmetic composition.

[0098] The liquid extract described in the present invention is useful for treating and preventing skin aging, particularly for treating and preventing the formation of skin spots.

[0099] The synergistic action of the components of the extract makes it possible to obtain a topical skin composition with a comprehensive anti-aging action, ie a product capable of preventing and treating skin aging by acting on the different mechanisms involved in this process.

[0100] As an illustrative but not exhaustive list, these mechanisms are collagen degradation, free radical production, inflammation and inflammatory aging, mechanisms involved in cellular senescence, improper cell to cell communication due to aging mechanisms, skin barrier dysfunction.

[0101] In view of the above, the cosmetic composition of the present invention can also be interpreted as comprising the following cosmetic composition:

[0102] White Morus alba twigs and / or twigs extract

[0103] Propylene glycol i. and

[0104] · Erythritol ii.

[0105] In fact, when the cosmetic composition is in the form of a water-in-oil or oil-in-water emulsion, the water present in the liquid extract of the present invention cannot be distinguished from the water already present in the cosmetic composition, for which reason the key components in the final cosmetic composition of the present invention are the white Morus alba twig and / or twig extract, propylene glycol i. and erythritol ii.

[0106] Thus, apart from the weight % content, the extract of white mulberry twigs and / or twigs, propylene glycol 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 propylene glycol i. is between 0.59 wt. % and 2.69 wt. %, preferably between 0.620 wt. % and 2.58 wt. %, and more preferably between 0.625 wt. % and 2.58 wt. %, based on the weight of the cosmetic composition.

[0107] According to another preferred embodiment of the final composition, erythritol ii. is contained between 0.038% and 0.33% by weight, preferably between 0.055% and 0.32% by weight, more preferably between 0.055% and 0.3% by weight, based on the weight of the cosmetic composition.

[0108] According to a further preferred embodiment, the cosmetic composition maintains a weight ratio i / ii of the liquid extract according to the invention as described above, said weight ratio being comprised between 7.75 and 16.50, preferably between 10.66 and 13.00.

[0109] The white mulberry twig and / or twig extract present in the cosmetic composition preferably comprises morusin A and oxyresveratrol.

[0110] Thus, except for the weight % content, oxidized resveratrol and morusin A are as described above, including advantageous and preferred embodiments. Preferably, oxidized resveratrol is included between 0.0001 wt% and 0.004 wt%, more preferably 0.0002 wt% to 0.002 wt%, based on the weight of the cosmetic composition.

[0111] Preferably, Mulberoside A is contained between 0.00007 wt% and 0.0028 wt%, preferably between 0.0001 wt% and 0.0016 wt%, based on the weight of the cosmetic composition.

[0112] The above content ranges of morusin A and oxidized resveratrol can be easily derived from conditions II) to III) of the liquid extract of the present invention, and also taking into account that the liquid extract is contained in the cosmetic composition of the present invention in an amount of 1 wt % to 4 wt % based on the total weight of the cosmetic composition.

[0113] The above compounds are preferably contained in a phytocomplex extracted from twigs and / or twigs of white mulberry. Said phytocomplex is as described above, including advantageous and preferred embodiments.

[0114] In the case of cosmetic compositions having a water content of less than or equal to 0.05 wt. % before addition of the liquid extract of the present invention, the water content present in the liquid extract (which is much higher) also becomes a key component in the final cosmetic composition of the present invention containing the liquid extract of the present invention.

[0115] Therefore, water is preferably present in the cosmetic composition of the present invention in an amount of at least 0.28 wt.-%, more preferably at least 0.30 wt.-%, based on the total weight of the cosmetic composition.

[0116] According to a further preferred embodiment of the cosmetic composition according to the invention, the water content in % by weight iii. is at least 0.4*(i.+ii.), preferably (i.+ii.) / 2.33. This formula can be easily derived from the above condition IV) (i.+ii.) / iii for the liquid extract when the water content is equal to 2.5 or equal to 2.33.

[0117] All ranges of propylene glycol, erythritol, and water can be easily derived taking into account the above-mentioned conditions of the liquid extract of the present invention.

[0118] The composition of the present invention may contain an antioxidant different from Mulberiside A and oxidized resveratrol. This antioxidant is as described above, including advantageous and preferred embodiments. It may be added specifically to protect Mulberiside A and oxidized resveratrol, and is preferably selected from the group already mentioned, namely sodium metabisulfite and glutathione.

[0119] The above cosmetic composition is preferably in the form of a topical composition as described above. It thus presents the same uses, such as for the treatment and prevention of skin aging, in particular for the treatment and prevention of the formation of skin spots. For illustrative and non-limiting purposes, we report below the following examples.

[0120] Example

[0121] In order to identify components of skin-compatible extraction mixtures suitable for the purposes of the present invention, applicants have developed and performed various systematic extractions.

[0122] For each system, the applicants applied the following approach:

[0123] 1. Grind the botanicals (white mulberry twigs and / or twigs)

[0124] 2. Preparation of skin-friendly extraction mixture (solvent)

[0125] 3. Extraction: The herbs were contacted with a skin-friendly extract / solvent mixture at a ratio of 1:10 (w / w) and extracted in an ultrasonic bath at room temperature (25°C) for 1 hour.

[0126] 4. Filtration of the extract: The depleted botanicals were separated from the extraction solvent mixture by vacuum microfiltration using a Buchner funnel with a filter having a pore size of up to 0.22 microns. Such filtration methods are well known to those skilled in the art.

[0127] The liquid extract of the present invention corresponds to the filtered liquid in the final filtration step.

[0128] Steps 1 and 2, which are relevant for the purpose of the patent, are described in detail below. Steps 3 and 4 are methods well known to those skilled in the art.

[0129] Step 1 - Prepare the Herbs for Extraction

[0130] The liquid extract of the invention can be prepared starting from twigs and / or twigs of white mulberry.The method of preparing the herbal medicine involves a first step in which the twigs and / or twigs are dried in an oven (air dryer) at a temperature of 40°C until the humidity is below 10%.

[0131] The dried herb is then ground with a knife-type grinder until a powder having a maximum particle size of less than or equal to 6 mm, preferably less than or equal to 1 mm is obtained. This particle size is obtained by sieving the previously dried and ground botanical material through a sieve with mesh openings between 6 mm and 1 mm that excludes powders larger than these sizes.

[0132] The herbs thus obtained were subjected to various extraction tests, defined as "systematic extractions", by contacting them with different mixtures of ingredients. These mixtures are listed in Table 2.

[0133] Step 2 - Prepare a skin-friendly mixture as an extraction solvent

[0134] The first systematic extraction was used to investigate whether it was possible to combine two ingredients commonly used in cosmetics in such a way as to produce a mixture that could serve as an alternative solvent to a 70% ethanol-water mixture. In fact, it is known from the literature that ethanol is a good solvent for extracting compounds such as oxyresveratrol and morusin A from white mulberry plant material.

[0135] The ingredients shown in Table 1 were selected assuming a synergistic effect with the active ingredients extracted from plants to produce extracts for cosmetic use with the "claimed" comprehensive anti-aging effect.

[0136] The amount used for each raw material is shown in Table 2.

[0137] Example 1: Identification of carrier / solvent components

[0138] The first systematic extraction is used to identify the components that can make up the extraction mixture, each of which can meet the following characteristics:

[0139] It is a good carrier: that is, an ingredient that possesses the "required" functionality for cosmetic use. This step is particularly important because the applicants wish to produce an extract in which the solvent mixture itself serves as a vehicle for the final extract. Thus, in contrast to the prior art, no further steps are required after the extraction process to eliminate / remove the solvent or purify the extract from any contaminants.

[0140] ●It can act as a solvent, but at the same time it is skin-friendly / suitable for application and contains no irritating ingredients.

[0141] Production of ready-to-use extracts to be included in formulations for cosmetic use. In this context, we evaluate:

[0142] ■Must be in the physical state of liquid or powder soluble in water,

[0143] ■Chemical-physical stability,

[0144] ■ Color,

[0145] ■Viscosity;

[0146] ■ Ability to protect liquid extracts from microbial contamination. This last aspect is very important because aqueous extracts are more exposed to chemical degradation processes of the extracted active ingredients and microbial contamination than dry extracts.

[0147] ■Raw material costs

[0148] The formulator / applicant's selection favored raw materials containing at least one hydroxyl group, such as commercially available alcohols or polyols. 1,3-Propanediol was chosen for its corrosion-resistant properties and its low viscosity, which aids filtration. A list of the ingredients tested is shown in Table 1.

[0149] Table 1. Ingredients selected and used for extraction tests. For each raw material, the chemical structure, physical form and cosmetic requirements are also shown in the table.

[0150]

[0151]

[0152] Example 2: Extraction tests were performed using different mixtures of ingredients in Table 1 to identify the solvent mixture most suitable for the purpose of the present invention

[0153] For extraction, botanicals were mixed with the extraction mixture at a ratio of 1:10 (w / w) and extracted in an ultrasonic bath at room temperature (25°C) for 1 hour.

[0154] Table 2 shows the tested extract mixtures: for each extract, microbiological analysis and titration of the relevant actives (oxidized resveratrol and morusin A) were performed.

[0155] For microbiological analysis, analytical tests were performed according to the standard protocols ISO 21148:2017 known to those skilled in the art, and in particular ISO 21149:2017 for total bacterial load, and ISO 16212:201 for yeast and mold. For the culture counts of bacteria, yeast, and mold, TSA and SDA media (TSA = Tryptic Soy Agar; SDA = Sabouraud Dextrose Agar) were used. Microbial count values ​​on TSA / SDA media were considered acceptable for a number of <10 cfu / ml (cfu = colony forming units).

[0156] Titration of the active substance was performed by HPLC-UV DAD.

[0157] 1 g 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 vials for analysis. Analysis was performed using a Phenomenex Synergy RP MAX column as the stationary phase and methanol and water containing 0.1% formic acid as the mobile phase in an HPLC-DAD.

[0158] The stilbenoid compound oxidized resveratrol and its glycosylated derivative Morusoside A (Sigma-Aldrich) were used as reference standards. Readings were performed at 330 nm.

[0159] The T209 extract is the reference "gold standard" of the 70% ethanol extract disclosed in WO2020 / 201432.

[0160] Table 2 Extraction tests with microbial analysis and titer of oxidized resveratrol and morusin A

[0161]

[0162]

[0163] Completely unexpectedly, the applicants found that in the T244 and T290 extracts, the total titer of the two active ingredients was higher than or comparable to that in the ethanol extracts.

[0164] The T244 and T290 prototypes were able to extract both actives well. From the perspective of the titers of the two relevant active ingredients extracted from this system, the most promising prototypes were T244 and T290.

[0165] The system extraction was also used to evaluate the stability of the prototype at T = 5°C and room temperature T (25°C). This stability was performed over a period of six months. (Table 3)

[0166] Table 3 Thermal stability control

[0167]

[0168]

[0169] From these systematic experiments, prototypes T244 and T290 were selected because they demonstrated good solvent efficacy (meaning higher concentrations of the relevant active ingredient) and good stability under the temperature conditions tested.

[0170] Table 4 shows the prototypes that were selected to proceed with the subsequent system.

[0171] Table 4 Prototype names used in subsequent systems and their composition (in % of the total weight of the liquid extract)

[0172] Prototype number composition T244 Erythritol 8%, 1,3-propylene glycol 62%, water 30% T290 Water 6%, 1,3-propylene glycol 64%, water 30%

[0173] Example 3: Sensory stability test of the selected prototype after one month

[0174] In order to evaluate the sensory stability of the selected extracts after one month, a systematic study was set up in which each extract was subjected to stress conditions, namely:

[0175] Refrigerator (5℃) / dark

[0176] Room temperature (25°C) / light

[0177] Oven (40℃) / dark

[0178] In particular, each prototype was analyzed for its color and visual appearance: a darkening color change, the presence of any precipitate or turbidity of the solution indicated an unstable system.

[0179] The results are reported in Table 5.

[0180] Table 5 Control of the sensory stability of the prototypes selected in Example 2 after one month. "Good" means that there is no change in the sample with respect to color and presence of sediment or turbidity compared to T0.

[0181]

[0182] Under all conditions tested, the extracts tested showed no precipitation or turbidity at four weeks. In the light and oven, both extracts showed a slight darkening, while in the dark at 5°C they showed no color change.

[0183] Example 4: Stability test with addition of antioxidants

[0184] Based on the stability data of the T244 extract and the T290 extract, four different antioxidant systems were investigated to preserve the active ingredients oxidized resveratrol and morusin A that constitute the phytocomplex and to prevent the liquid extract from browning under the conditions tested in Table 5 and in which a color change was detected.

[0185] Two antioxidants were selected: sodium metabisulfite and glutathione.

[0186] Table 6 shows the prototypes studied and the conditions studied.

[0187] Table 6 Correlation between the names of the prototypes studied in Example 4 and the relevant compositions containing antioxidants

[0188]

[0189]

[0190] Table 7 also contains a control of the sensory stability of the prototypes at one month for an antioxidant selected between sodium metabisulfite and glutathione.

[0191]

[0192]

[0193] Figure 1 and Figure 2 The oxidized resveratrol ( Figure 1 )Mulberiside A( Figure 2 The values ​​shown in the figure refer to the % decrease compared to the initial titer of the active ingredient of each prototype.

[0194] The advantage of using a mixture of ingredients commonly known in cosmetic formulations as a solvent is that an extract is obtained that does not require further purification steps to eliminate the extraction solvent, because the extract mixture is a skin-friendly mixture and the functionality and microbiological stability of the extract itself are consistent. To the best of the applicant's knowledge, there is no such formulation that is ready to use and stable from a microbiological and organoleptic point of view, containing a phytocomplex comprising oxyresveratrol and morusin A.

[0195] The extracts thus obtained can be used in cosmetic formulations for the prevention and treatment of physiological mechanisms associated with aging and for skin health.

[0196] The following are some examples of recipes for illustrative but non-limiting purposes.

[0197] facial lotion

[0198] Components Range [% p / p] water Make up 100 moisturizer 1-20 Rheology modifiers 1-5 emulsifiers 0.5-3 preservative 0.1-1.5 spices 0.1-1 Hyaluronic acid 0.01-1 The liquid extract according to claim 1 1-4

[0199] O / W emulsion:

[0200]

[0201]

[0202] Sunscreen lotion:

[0203] Components Range [% p / p] water Make up 100 (Vegetable or mineral) oils, waxes, fats (e.g. long-chain alcohols) 5-10 UV filters 20-25 silicone 1-10 moisturizer 1-20 Rheology modifiers 1-5 emulsifiers 0.5-3 preservative 0.1-1.5 spices 0.1-1 chelating agents 0.1-0.3 antioxidants 0.03-0.5 Hyaluronic acid 0.01-1 The liquid extract according to claim 1 1-4

Claims

1. A liquid extract, comprising: A. A phytocomplex extracted from twigs and / or twigs of white mulberry, said phytocomplex comprising a. Oxidized resveratrol, b. Mulberry glycoside A B. A solvent mixture in which the plant complex A is dissolved, said mixture comprising: i.1,3-Propanediol ii. Erythritol iii. Water in: I. Mixed solvent B) is the extraction solvent II. The concentration of a. of the plant 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. of the phytocomplex 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 of the solvent mixture B (i.+ii.) / iii. is comprised between 2.00 and 2.50, preferably 2.33 V. The weight ratio i. / ii. of the solvent mixture B is comprised between 7.75 and 16.50, preferably it is comprised between 10.66 and 13.00 VI. The sum of the weights of i.+ii.+iii.=100.

2. The liquid extract according to claim 1, wherein: - the water content iii. in the solvent mixture B is 30% by weight based on the total weight of the solvent; - the concentration of 1,3-propylene glycol i. in the solvent mixture B is comprised between 62.5% and 64.5% by weight, based on the total weight of solvent B, and - the concentration of erythritol ii. in the solvent mixture B is comprised between 5.5% and 7.5% by weight, based on the total weight of the solvent.

3. The liquid extract according to claim 2, wherein the solvent mixture B comprises an antioxidant.

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

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 wt% and 0.2 wt% based on the total weight of the solvent mixture B.

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

7. A method for preparing the liquid extract according to any one of claims 1 to 6, comprising the following steps:

1. Drying the twigs and / or twigs of white mulberry at a temperature equal to 40°C and until the humidity is less than 10%; 2. Grind and sieve the dried product from step 1 until a homogeneous powder with a size less than or equal to 6 mm is obtained; 3. Prepare solvent mixture B, comprising the following steps at room temperature: 3.

1. Mix erythritol ii. with water iii. until completely dissolved. 3.

2. Add 1,3-propylene glycol with stirring until a clear solution is obtained; 4. The dry powder obtained in step 2 is mixed with the solvent mixture B prepared in step 3 at a dry powder / solvent mixture B weight ratio between 1:8 and 1:12, preferably 1:10, in an ultrasonic bath at room temperature for 1 hour; 5. Remove the solid residue resulting from step 4 by vacuum filtration at least twice using filters with pore sizes up to 0.22 microns.

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

9. The cosmetic topical composition of claim 8, wherein the liquid extract is present in an amount between 1 wt% and 4 wt% based on the total weight of the composition.

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

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

12. Cosmetic use of the liquid extract according to any one of claims 1 to 6 for the treatment and prevention of skin aging.

13. A cosmetic composition comprising: White Morus alba twigs and / or twigs extract Propylene glycol and · Erythritol ii.

14. The cosmetic composition according to claim 13, wherein the content of propylene glycol i. is between 0.59 wt.% and 2.69 wt.%, preferably between 0.620 wt.% and 2.58 wt.%, more preferably between 0.625 wt.% and 2.58 wt.%, based on the weight of the cosmetic composition.

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

16. 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. The cosmetic composition according to any one of claims 13 to 16, wherein the twig and / or twig extract comprises morusin A and oxidized resveratrol.

18. The cosmetic composition according to claim 17, wherein the oxidized resveratrol is contained between 0.0001 wt% and 0.004 wt%, preferably between 0.0002 wt% and 0.002 wt%, based on the weight of the cosmetic composition.

19. The cosmetic composition according to claim 17 or claim 18, wherein the mulberryside A is contained between 0.00007 wt% and 0.0028 wt%, preferably between 0.0001 wt% and 0.0016 wt%, based on the weight of the cosmetic composition.

20. The cosmetic composition according to any one of claims 17 to 19, wherein the morusin A and the oxidized resveratrol are contained in a phytocomplex extracted from twigs and / or twigs of Morus alba.

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

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

23. The cosmetic composition according to claim 21 or claim 22, wherein the water content is in wt% of at least 0.4*[(i)+(ii)], preferably [(i)+(ii)] / 2.33, based on the total weight of the composition.

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

Images