Topical compositions containing vitamin C

Abstract

The present invention provides topical compositions comprising a combination of ascorbic acid, epigallocatechin gallate, water, and 1, 3-propanediol.

Description

Technical Field

[0001] The present invention provides a topical composition comprising a combination of ascorbic acid, epigallocatechin gallate, water, and 1,3-propylene glycol. Background Art

[0002] Ascorbic acid (vitamin C) is widely used in skin care for its antioxidant and skin lightening properties. Anhydrous ascorbic acid formulations are not as effective as aqueous systems in delivering ascorbic acid. However, the stability of ascorbic acid in aqueous carriers is known to be challenging because water increases the oxidation kinetics of ascorbic acid.

[0003] Applicants have now discovered improved topical compositions, preferably in the form of slurries, containing high levels of ascorbic acid stabilized in a unique aqueous vehicle containing 1,3-propylene glycol. The composition also contains epigallocatechin gallate (EGCG), a polyphenol found in green tea that also has powerful antioxidant properties. The combination of ascorbic acid and EGCG in the composition advantageously provides synergistic antioxidant activity and excellent anti-aging and skin lightening benefits. Summary of the invention

[0004] The present invention provides a topical composition comprising at least 10 weight percent ascorbic acid, about 0.05 weight percent to about 2.5 weight percent epigallocatechin gallate, water and 1,3-propylene glycol, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.6.

[0005] The present invention also provides a topical composition comprising at least 15 weight percent ascorbic acid, about 0.1 weight percent epigallocatechin gallate, feverfew extract, gluconolactone, water, and at least 40 weight percent 1,3-propylene glycol, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.6.

[0006] The present invention also provides cosmetic methods for treating the skin comprising topically applying these topical compositions to skin in need of skin lightening or whitening treatment. DETAILED DESCRIPTION

[0007] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. All publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference.

[0008] As used herein, "topical application" means applying or spreading directly onto the outer skin, scalp, or hair, for example, by hand or with an applicator such as a wipe, roller, or spray.

[0009] As used herein, "cosmetically acceptable" means that the ingredients described by the term are suitable for use in contact with tissue (eg, skin or hair) without undue toxicity, incompatibility, instability, irritation, allergic response, and the like.

[0010] As used herein, a "cosmetically acceptable active agent" is a compound (synthetic or natural) that has a cosmetic or therapeutic effect on the skin or hair.

[0011] The compositions of the present invention are useful for treating signs of skin aging. As used herein, "signs of skin aging" include the presence of lines, including fine lines and wrinkles, loss of elasticity, uneven skin tone, scarring, decreased skin thickness, and abnormal or reduced synthesis of collagen, glycosaminoglycans, proteoglycans, elastin, or glycoproteins, including fibronectin. In one embodiment, the signs of aging are selected from the presence of lines, fine lines, wrinkles, loss of elasticity, and abnormal or reduced synthesis of collagen, glycosaminoglycans, proteoglycans, elastin, or glycoproteins, including fibronectin.

[0012] The compositions of the present invention are also suitable for treating skin that requires lightening or whitening treatment. As used herein, the term "lightening" or "whitening" the skin generally refers to lightening, brightening, whitening and / or evening out skin tone, skin color and / or skin sheen, and / or refers to reducing sallowness, and / or refers to lightening and / or fading hyperpigmentation marks and / or lesions, including but not limited to pigmented spots, melanin spots, age spots, sun spots, age freckles, freckles, simple freckles, pigmented solar keratosis, seborrheic keratosis, melasma, acne marks, post-inflammatory pigmentation, moles, acne, combinations of two or more thereof, and the like. "Lightening" or "whitening" the skin also refers to increasing the radiance, vitality, clarity and / or luminescence of the skin and / or obtaining a more radiant, vibrant, clear or luminous skin tone appearance or making the skin tone less yellow or sallow. In certain preferred embodiments, "lightening" or "brightening" the skin refers to lightening and even-toning the skin tone, increasing skin radiance, and / or fading age spots. In certain other preferred embodiments, the present invention relates to compositions and methods for use on skin in need of skin lightening or brightening treatment, the skin being selected from sallow and / or dull skin. In certain other preferred embodiments, the present invention relates to compositions and methods for use on skin in need of skin lightening or brightening treatment, the skin being selected from age spots, freckles, marks left after acne, and combinations of two or more thereof.

[0013] As used herein, "treating" or "treatment" means ameliorating, preventing, or reversing a condition, disease, or disorder, or at least one identifiable symptom thereof. In one embodiment, "treating" or "treatment" refers to ameliorating, preventing, or reversing at least one measurable physical parameter associated with the condition, disease, or disorder being treated, which is not necessarily identifiable in or by the subject being treated. In another embodiment, "treating" or "treatment" refers to inhibiting or slowing the progression of a condition, disease, or disorder, which may be physical (e.g., stabilizing an identifiable symptom), physiological (e.g., stabilizing a physical parameter), or both. In another embodiment, "treating" or "treatment" refers to delaying the onset of a condition, disease, or disorder.

[0014] In certain embodiments, the compositions of the invention are administered as a preventive measure.As used herein, "prevention" refers to reducing the risk of developing a given condition, disease, or disorder.

[0015] More broadly, the compositions of the present invention may also be used to treat or prevent cosmetic, dermatological or other conditions and disorders, including but not limited to infections associated with the skin, nails and hair, imbalances or disorders of the skin or mucocutaneous tissues; oral, vaginal and anal mucosa; keratinization disorders; inflammation; changes associated with intrinsic and extrinsic aging, and other changes that may or may not be related to the integumentary system. Manifestations include, but are not limited to, oily skin; acne; rosacea; age spots; blemished skin; eruptions; cellulite; skin disorders; dermatitis; skin, nail and hair infections; dandruff; dry or loose skin, nails and hair; xerosis; inflammation or eczema; elastosis; herpes; hyperkeratosis; hyperpigmentation of the skin; ichthyosis; keratosis; freckles; melasma; mottled skin; pseudofolliculitis; photoaging and photodamage; pruritus; psoriasis; striae; stretch marks; thinning of the skin, nails and hair; warts; wrinkles; mouth or gum disease; irritation, inflammation, redness, unhealthy, damaged or abnormal mucous membranes, skin Disorders of the skin, hair, nails, nostrils, ear canals, anus, or vagina; breakdown, defective synthesis, or repair of dermal components; abnormal or diminished synthesis of collagen, glycosaminoglycans, proteoglycans, and elastin, and decreased levels of such components in the epidermis; uneven skin tone; uneven and rough surface of the skin, nails, and hair; loss or reduction of the resilience, elasticity, and curlability of the skin, nails, and hair; sagging; lack of skin, nail, and hair lubricity and shine; brittle and split nails and hair; yellowing of the skin; reactive, irritated, or telangiectatic skin; and dull, older-looking skin, nails, and hair. In addition, the compositions of the present invention can be used for general care of the skin, nails and hair; improving skin texture and pores, shine and redness; making the skin soft, smooth, refreshed, balanced, visibly clean, even-toned and brighter; increasing skin fullness and volume; and for skin bleaching and lightening and wound healing; reducing or preventing sweating or perspiration in the underarms, crotch, palms or other parts of the body.

[0016] As used herein, the term "subject" means any animal, preferably a mammal, most preferably a human, to which the composition of the present invention is to be or has been administered. As used herein, the term "mammal" encompasses any mammal. Examples of mammals include, but are not limited to, cows, horses, sheep, pigs, cats, dogs, mice, rats, rabbits, guinea pigs, monkeys, and humans. In a preferred embodiment, the subject is a human.

[0017] As used herein, "wrinkles" include fine lines, micro wrinkles or macro wrinkles. Examples of wrinkles include, but are not limited to, fine lines around the eyes (eg, "crow's feet"), forehead and cheek wrinkles, frown lines, and smile lines around the mouth.

[0018] As used herein, "loss of elasticity" includes loss of elasticity or structural integrity of skin or tissue, including but not limited to sagging, loose and loose tissue. Loss of elasticity or tissue structural integrity can be caused by a variety of factors, including but not limited to disease, aging, hormonal changes, mechanical trauma, environmental damage, or is the result of applying products such as cosmetics or drugs to the tissue.

[0019] As used herein, "uneven skin" refers to a skin condition associated with diffuse or mottled pigmentation that can be classified as hyperpigmentation, such as post-inflammatory hyperpigmentation.

[0020] As used herein, "erythema" means a skin condition associated with redness or erythema.

[0021] As used herein, "cosmetic" means any agent that preserves, restores, imparts, stimulates or enhances the physical appearance or appears to enhance beauty or promote youthfulness, especially as it relates to the appearance of tissue or skin.

[0022] As used herein, "cosmetically effective amount" means an amount sufficient to treat or prevent one or more signs of skin aging, but sufficiently low to avoid serious side effects. The cosmetically effective amount of a compound or composition will vary depending on the specific condition being treated, the age and physical condition of the end user, the severity of the condition being treated / prevented, the duration of treatment, the nature of other treatments, the specific compound or product / composition employed, the specific cosmetically acceptable carrier employed, etc.

[0023] As used herein, "substantially free" means that the referenced ingredient is not directly or intentionally added to the formulation. Preferably, "substantially free" means containing less than about 1% of an ingredient. More preferably, "substantially free" means containing less than about 0.5% of an ingredient. Even more preferably, "substantially free" means containing less than about 0.1% by weight of an ingredient. The compositions of the present invention may be completely free of ingredients, i.e., contain no ingredients at all.

[0024] Unless otherwise indicated, percentages or concentrations refer to weight percentages or weight concentrations (i.e., % (weight / weight)). The weight percentage of an ingredient is based on the total weight of the composition containing the ingredient. Unless otherwise indicated, all ranges include endpoints, for example, "4 to 9" includes endpoints 4 and 9.

[0025] ascorbic acid

[0026] The composition contains ascorbic acid, also known as vitamin C. Ascorbic acid has the following structure:

[0027]

[0028] The composition contains unexpectedly high levels of vitamin C. The composition contains at least 10 weight % ascorbic acid based on the total weight of the composition. The composition may contain at least 15 weight % ascorbic acid based on the total weight of the composition.

[0029] The compositions can contain unexpectedly high levels of vitamin C that remain stable over time. As is known in the art, compositions containing vitamin C are preferably prepared with excess ingredients to account for some degradation over the shelf life of the product.

[0030] Epigallocatechin gallate (EGCG)

[0031] The composition further contains EGCG. The amount of EGCG in the composition may be in the range of about 0.05 wt % to about 2.5 wt % based on the total weight of the composition.

[0032] Preferably, the composition contains about 0.1 wt % EGCG based on the total weight of the composition.

[0033] Water-based carrier

[0034] The composition comprises an aqueous carrier comprising water and 1,3-propylene glycol. Preferably, water and 1,3-propylene glycol are the only solvents in the composition.

[0035] The weight ratio of water: 1,3-propylene glycol is at least 0.6. This carrier unexpectedly provides excellent stability of ascorbic acid in the composition over time. The weight ratio of water: 1,3-propylene glycol may be at least 0.8.

[0036] Based on the total weight of the composition, the amount of water in the composition may be in the range of about 20% to about 40% by weight of the composition. Preferably, based on the total weight of the composition, the amount of water in the composition is about 30% by weight of the composition.

[0037] The amount of 1,3-propylene glycol in the composition is preferably at least 40% by weight of the composition, based on the total weight of the composition. More preferably, the amount of 1,3-propylene glycol in the composition is at least 45% by weight of the composition, based on the total weight of the composition.

[0038] Other cosmetically acceptable active agents

[0039] The compositions may contain one or more additional cosmetically acceptable active agents.

[0040] Such cosmetically acceptable active agents include, for example, other anti-aging agents, other antioxidants, anti-acne agents, shine control agents, antimicrobial agents, anti-inflammatory agents, antifungal agents, antiparasitic agents, topical analgesics, sunscreens, photoprotectants, keratolytics, surfactants, moisturizers, nutrients, other vitamins, energizers, antiperspirants, astringents, deodorants, firming agents, anti-hardness agents, and agents for hair and / or skin conditioning.

[0041] The amount of other cosmetic active agents in the composition may range from about 0.001% to about 20% by weight of the composition, e.g., from about 0.005% to about 10% by weight of the composition, such as from about 0.01% to about 5% by weight of the composition, based on the total weight of the composition.

[0042] The cosmetically acceptable active agent may be selected from, for example, alpha hydroxy acids and polyhydroxy acids (such as glycolic acid, lactic acid, malic acid, salicylic acid, citric acid, tartaric acid and gluconolactone), benzoyl peroxide, D-panthenol carotenoids, retinoids (such as retinol and retinyl palmitate), ceramides, polyunsaturated fatty acids, essential fatty acids, enzymes (such as laccase), enzyme inhibitors, minerals, hormones (such as estrogens), steroids such as hydrocortisone, 2-dimethylaminoethanol, copper salts such as copper chloride, polypeptides such as hexapeptides and tripeptides, those containing copper, coenzyme Q10, amino acids (such as proline), vitamins, lactobionic acid, acetyl-CoA, niacin, riboflavin, thiamine, ribose, electron transporters (such as NADH and FADH2), natural extracts (such as from Moringa oleifera), Oleifera) seeds, aloe vera, feverfew (e.g., Chrysanthemum Partheniu (feverfew chamomile) flower / leaf / stem juice), oatmeal, dill, blackberry, paulownia tomentosa, aspen lemon), resorcinol (such as 4-hexylresorcinol), curcumin, sugar amines (such as N-acetylglucosamine), and derivatives and mixtures thereof.

[0043] Examples of other vitamins include, but are not limited to, vitamin A, B vitamins (such as vitamin B3, vitamin B5, and vitamin B12), vitamin K, and different forms of vitamin E (such as alpha, beta, gamma, and delta tocopherol or mixtures thereof), and their derivatives.

[0044] Examples of other antioxidants include, but are not limited to, water-soluble antioxidants such as sulfhydryl compounds and their derivatives (e.g., sodium metabisulfite and N-acyl-cysteine), lipoic acid and dihydrolipoic acid, resveratrol, lactoferrin, and ascorbic acid derivatives (e.g., ascorbyl palmitate and ascorbic acid polypeptides). Oil-soluble antioxidants suitable for use in the compositions of the present invention include, but are not limited to, butylated hydroxytoluene, retinoids (e.g., retinol and retinyl palmitate), tocopherols (e.g., tocopheryl acetate), tocotrienols, and ubiquinone. Natural extracts containing antioxidants suitable for use in the compositions of the present invention include, but are not limited to, extracts containing flavonoids and isoflavones and their derivatives (e.g., genistein and diadzein), extracts containing resveratrol, and the like. Examples of such natural extracts include grape seeds, pine bark, and propolis.

[0045] The composition may, for example, comprise ascorbic acid, EGCG and Moringa seed extract. Such a composition may comprise at least 10% by weight of ascorbic acid and about 0.1% by weight of EGCG. Preferably, such a composition further comprises about 0.5% by weight of Moringa seed extract.

[0046] The composition may preferably include ascorbic acid, EGCG, feverfew extract and gluconolactone. Such a composition may include at least 15% by weight of ascorbic acid and about 0.1% by weight of EGCG. Preferably, such a composition also includes about 1% by weight of feverfew extract and about 2% by weight of gluconolactone.

[0047] Topical compositions

[0048] The compositions of the present invention may be applied topically to the skin or hair, preferably the skin.They are single phase aqueous compositions.

[0049] The composition can be formulated into a variety of liquid product types, including but not limited to solutions, lotions, creams, gels, sprays, ointments and lotions. The composition is preferably in the form of a slurry, which is a light and easy to spread on the skin and absorbed by the skin.

[0050] The composition may contain one or more emollients known in the art. As used herein, "emollient" refers to a substance used to prevent or relieve dryness, such as by preventing water from being lost through the epidermis from the skin. Examples of emollients include, but are not limited to, those described in the International Cosmetic Ingredient Dictionary and Handbook, edited by Pepe, Wenninger and McEwen, pp. 2930-2936 (American Cosmetic and Fragrance Association, Washington, DC, 9th edition, 2002) (hereinafter, "ICI Handbook"). Examples of particularly suitable emollients include vegetable oils, mineral oils, fatty acid esters, etc.

[0051] The composition may also be formulated as a gel (e.g., an aqueous gel, an alcoholic gel, an alcohol / aqueous gel, or an oily gel using a suitable gelling agent). Suitable gelling agents for aqueous and / or alcoholic gels include, but are not limited to, natural gums, acrylic acid and acrylate polymers and copolymers, and cellulose derivatives (e.g., hydroxymethylcellulose and hydroxypropylcellulose). Suitable gelling agents for oils (such as mineral oils) include, but are not limited to, hydrogenated butylene / ethylene / styrene copolymers and hydrogenated ethylene / propylene / styrene copolymers. Such gels typically contain from about 0.1% to 5% by weight of such gelling agents.

[0052] In addition to the above components, the composition may contain a variety of other oil-soluble and / or water-soluble materials that are commonly used in compositions for use on skin and hair at levels established in the art. These materials include humectants, pH adjusters, fragrances, dyes, and preservatives (e.g., parabens).

[0053] The composition may comprise one or more oils. As used herein, the term "oil" means a hydrophobic material such as hydrocarbon oils, silicones, fatty acid derivatives, glycerides, vegetable oils, vegetable oil derivatives, alkyl esters, wax esters, beeswax derivatives, sterols and phospholipids.

[0054] Suitable hydrocarbon oils include petrolatum, mineral oil, microcrystalline wax, squalene, and combinations thereof.

[0055] Silicone oils include dimethicone, dimethiconol, phenyl dimethicone, and cyclic polysiloxanes, and combinations thereof. Silicone oils having a viscosity of from about 0.5 centistoke to about 100,000 centistoke at 25°C may also be used in the composition.

[0056] Glycerides include castor oil, sunflower seed oil, coconut oil and derivatives, vegetable oils and derivatives, palm oil, jojoba oil, shea butter, lanolin, and combinations thereof.

[0057] Alkyl ester oils include, but are not limited to, isopropyl esters of fatty acids and esters of long-chain fatty acids. More preferably, the following alkyl esters are available: isopropyl palmitate, isopropyl myristate, myristyl myristate, isohexyl palmitate, decyl oleate, isononyl isononanoate, and combinations thereof.

[0058] Preferably, the composition contains caprylyl glycol. More preferably, the composition contains at least about 0.25 wt % caprylyl glycol based on the total weight of the composition. For example, the composition may contain at least about 0.5 wt % caprylyl glycol based on the total weight of the composition.

[0059] The composition may be substantially free of phenoxyethanol.

[0060] pH

[0061] In one embodiment, the topical composition has a pH of about 3.6 to about 4.2. For example, the pH may be about 3.8.

[0062] The topical composition may include a buffer such as lactic acid, citric acid, malic acid, tartaric acid, gluconic acid, or gluconolactone to maintain pH. Typically, the composition includes about 2% to about 12% by weight, or about 4% to about 8% by weight of a buffer.

[0063] How to treat your skin

[0064] According to the present invention, skin in need of skin lightening or whitening treatment may be treated by topically applying a composition comprising at least 10 weight percent ascorbic acid, from about 0.05 weight percent to about 2.5 weight percent epigallocatechin gallate, water, and 1,3-propylene glycol, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.6.

[0065] Also according to the present invention, skin in need of skin lightening or whitening treatment can be treated by topically applying a composition comprising: at least 15 wt % of ascorbic acid based on the total weight of the composition, about 0.1 wt % of epigallocatechin gallate based on the total weight of the composition, feverfew extract, gluconolactone, water, and at least 40 wt % of 1,3-propylene glycol based on the total weight of the composition, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.6.

[0066] The composition according to the present invention comprises at least 10 wt% ascorbic acid, EGCG, water and 1,3-propylene glycol, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.6, and also advantageously and surprisingly provides excellent ascorbic acid solubility and stability.

[0067] The following non-limiting examples will further illustrate the present invention.

[0068] Example 1

[0069] The stability of three compositions was tested, each containing 17 wt% ascorbic acid, 0.1 wt% EGCG, 2 wt% gluconolactone, and 1 wt% feverfew in a water / 1,3-propylene glycol vehicle. The compositions had different weight ratios of water to 1,3-propylene glycol, as shown in Table 1 below. However, the combined total amount of water and 1,3-propylene glycol was the same in all compositions, at 77.25 wt%.

[0070] The compositions were tested for ascorbic acid solubility by visually evaluating and recording the presence or absence of ascorbic acid crystals at 4°C.

[0071] The results are also shown in Table 1.

[0072] Table 1

[0073] Composition 1 Composition 2 Composition 3 Purified water 25.25％ 29.55％ 33.45％ 1,3-Propanediol 52.00％ 47.70％ 43.80％ ascorbic acid 17.00％ 17.00％ 17.00％ Gluconolactone 2.00％ 2.00％ 2.00％ Epigallocatechin gallate 0.10％ 0.10％ 0.10％ Feverfew Extract 1.00％ 1.00％ 1.00％ Sodium hydroxide, 10% (w / w) in water 2.65(QS) 2.65(QS) 2.65(QS) 4C 1 month 1 week (cold) Many crystals A crystal clarify 4C 1 month 1 week (25C) Many crystals clarify clarify 4C 1 month 3 weeks (cold) Many crystals clarify Many crystals 4C 2 months (25C) Many crystals clarify clarify 4C 2 months 1 week (cold) Many crystals clarify clarify Water: 1,3-propylene glycol weight ratio 0.4856 0.6195 0.7637

[0074] These results show that the compositions according to the present invention containing ascorbic acid and EGCG and having a water to 1,3-propylene glycol weight ratio of about 0.6 or more have superior stability to compositions containing the same ingredients but having a water to 1,3-propylene glycol weight ratio of less than 0.6, even when containing the same total amount of water and 1,3-propylene glycol. In addition, surprisingly, Composition 2, which contains a moderate amount of water (29.55 wt%) and has a moderate water to 1,3-propylene glycol weight ratio (0.6195), provides the best ascorbic acid stability among the three compositions.

[0075] Example 2

[0076] The stability of three compositions was tested, each containing 17 wt % ascorbic acid, 0.1 wt % EGCG, and 1 wt % feverfew in a water / 1,3-propylene glycol vehicle. The compositions contained different amounts of gluconolactone (2%, 0.5%, and 0% by weight), as shown in Table 2.

[0077] The composition was prepared in the same manner as described in Example 1.

[0078] The compositions were tested for ascorbic acid stability as follows: The compositions were monitored at 25°C / 60% relative humidity (RH) and 40°C / 75% RH. The ascorbic acid concentration of the samples was determined initially and at several time points over a 12 week period by HPLC analysis.

[0079] The results are shown in Table 2.

[0080] Table 2

[0081] Composition 4 Composition 5 Composition 6 Purified water 29.55％ 29.55％ 29.55％ 1,3-Propanediol 47.70％ 49.20％ 49.7％ ascorbic acid 17.00％ 17.00％ 17.00％ Gluconolactone 2.00％ 0.50％ 0.00％ Epigallocatechin gallate 0.10％ 0.10％ 0.10％ Feverfew Extract 1.00％ 1.00％ 1.00％ Sodium hydroxide, 10% (w / w) aqueous solution 2.65(QS) 2.65(QS) 2.65(QS) Initial Vitamin C Content 16.97％ 17.05％ 17.02％ 1 month 40C test 15.48％ 15.36％ 13.61％ 2 months 40C test 14.37％ 13.55％ Water: 1,3-propylene glycol weight ratio 0.6195 0.6006 0.5946

[0082] These results surprisingly show that ascorbic acid stability increases with increasing amounts of gluconolactone in the formulation. Composition 5, containing 2 wt% gluconolactone and a water:1,3-propylene glycol weight ratio of 0.6195, had the greatest ascorbic acid stability of all three compositions.

[0083] Example 3

[0084] The combined antioxidant effect of ascorbic acid in combination with various other known antioxidants was tested using the oxygen radical absorbance capacity (ORAC) assay according to the method described by Ou B, Hampsch Woodill M, Prior RL. Development and validation of an improved oxygen radical absorbance capacity assay using fluorescein as a fluorescent probe. JAgric Food Chem. 2001: 49: 4619 (using a slightly different excitation / emission wavelength reading and a narrower range of Trolox standards). The assay measures the ability of the antioxidant "chain breaker" to inhibit the decrease in fluorescence of fluorescein disodium (FL) induced by the peroxyl radical generator 2', 2'-azobis(2-amidinopropane) dihydrochloride (AAPH). Distilled water was used as a negative control. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid, a water-soluble analog of vitamin E with antioxidant properties sold by Hoffman-LaRoche) was used as a positive control.

[0085] The final ORAC value was calculated from the regression equation of the net area under the FL decay curve using the formula where area under the curve (AUC) = 1 + (point 1 + point 2 + point 3 + ... + point 15) / point 1. The Trolox standard was then plotted in micromoles versus AUC. The samples were solved using their AUC to obtain values ​​in micromoles (μmol) Trolox equivalents (TE) / ml. Quantification was performed using a Biosystems Cytofluor 4000 fluorometer and software. The ORAC values ​​of the test materials are expressed in μmol TE / ml (TE = Trolox equivalents).

[0086] All components were stored at room temperature and diluted with distilled water to make aqueous stock solutions for testing. Further dilutions were performed in distilled water within 24 hours of testing.

[0087] The results are shown in Tables 3 and 4, which report two separate test runs.

[0088] Table 3

[0089]

[0090]

[0091] Table 3

[0092]

[0093] Example 4

[0094] Two topical compositions according to the present invention were prepared using the ingredients shown in Table 4.

[0095] Table 4

[0096] Composition 7 Composition 8 INCI name %w / w %w / w water 31.616 39.35 1,3-Propanediol 46.95 47 Disodium EDTA 0 0.2 Epigallocatechin gallate 0.1 0.1 Phenoxyethanol 0.5 0 Caprylyl Glycol 0.25 0.25 ascorbic acid 17 12.5 Gluconolactone 2 0 Feverfew (Chamomile) flower / leaf / stem juice 1 0 Water; Glycerin; Moringa Seed Extract 0 0.5 Sodium hydroxide 0.584 0.1 total 100 100 Water: 1,3-Propanediol 0.6734 0.8372

[0097] Example 5

[0098] A 12-week, institutional review board-approved, single-center, prospective clinical study was conducted using Composition 7 according to the present invention (Table 4) and directly compared with baseline conditions.

[0099] The study population was female, aged 30 to 60 years, with Fitzpatrick skin types I-VI. Key inclusion criteria were moderate scores (modified Griffith's scale) for overall facial lack of clarity and radiance and mild to moderate uneven skin tone; textural parameters such as fine lines and wrinkles were appropriately included to ensure all skin tones were included. Forty-four racially and ethnically diverse women representing all Fitzpatrick skin types (I-VI) completed the study; 43% Black / African American, 18% Asian, 37% Caucasian, 2% Multiracial, 9% Hispanic / Latino.

[0100] Clinical grading of pigmentation, texture attributes, and tolerance, as well as self-assessment questionnaires and digital photographs were collected. At each visit, the clinical grading score for each subject was compared with the baseline score using the Wilcoxon signed-rank test, p < 0.05. The percentage change from baseline was calculated based on the mean incremental score. The self-assessment scores were tabulated.

[0101] Composition 7 was applied once daily in the morning. A mild daytime SPF 35 and nighttime moisturizer were provided to regularize the regimen.

[0102] All 12 clinical grading parameters (hyperpigmentation, skin tone evenness, clarity, radiance / luminosity / brightness, fine lines, wrinkles, pore size, laxity, overall lift, tactile roughness / smoothness, visual roughness / smoothness, and overall photodamage / appearance) showed significant improvements at week 12, p<0.05.

[0103] Eight of the 12 parameters (fine lines, wrinkles, pore size, laxity, overall lift, tactile roughness / smoothness, visual roughness / smoothness, and overall photodamage / appearance) improved significantly at week 4 and sustained improvements through weeks 8 and 12, p ≤ 0.05. This included all four pigmentation / brightening parameters: hyperpigmentation, even skin tone, clarity, and radiance / luminosity / brightness.

[0104] The self-assessment results are as follows:

[0105] Early benefits noticed after 1 week

[0106] 98% skin tone is brighter and more radiant

[0107] 100% smoother texture

[0108] 1 Multiple benefits on hyperpigmentation and texture after 2 weeks

[0109] 100% brighter skin

[0110] 95% skin tone was visibly brighter

[0111] 95% skin feels protected from environmental stressors

[0112] 95% of fine lines are less noticeable

[0113] 93% had a more even skin tone

[0114] 90% of dark spots are less noticeable

[0115] Thus, Composition 7 according to the present invention advantageously delivers clinical and consumer-perceivable overall facial skin lightening benefits across a diverse population representing all skin tones.

Claims

1. A topical composition comprising at least 10 weight percent ascorbic acid, from about 0.05 weight percent to about 2.5 weight percent epigallocatechin gallate, water, and 1,3-propylene glycol, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.

6.

2. The composition of claim 1, comprising about 0.1 wt% epigallocatechin gallate based on the total weight of the composition.

3. The composition of claim 1, comprising at least 40 weight percent of 1,3-propylene glycol based on the total weight of the composition.

4. The topical composition of claim 1, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.

8.

5. The composition of claim 1, having a pH of about 3.6 to about 4.

2. The composition according to claim 1 , which is in the form of a single aqueous phase.

7. A topical composition comprising: at least 15 weight % of ascorbic acid based on the total weight of the composition, about 0.1 weight % of epigallocatechin gallate based on the total weight of the composition, feverfew extract, gluconolactone, water, and at least 40 weight % of 1,3-propylene glycol based on the total weight of the composition, wherein the weight ratio of water to 1,3-propylene glycol in the composition is at least 0.

6.

8. A cosmetic method for treating the skin, the method comprising topically applying the topical composition according to claim 1 to skin in need of skin lightening or whitening treatment.

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