Methods of skin whitening by use of canola extracts

Abstract

To provide compositions and methods for lightening skin.SOLUTION: A method for lightening skin may include the step of identifying the position on the skin where lightening or whitening is desired and topically applying to the skin a composition including (a) a skin lightening agent comprising a canola extract and (b) a cosmetically acceptable carrier. A method for treating hyperpigmentation may include the step of identifying the skin containing areas of hyperpigmentation and topically applying to the skin a composition including (a) a canola extract and (b) a cosmetically acceptable carrier.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a composition of canola extract containing high levels of phenolic acids and methods of using them for skin whitening.

Background Art

[0002] In humans, melanin is the main determinant of skin color. In the skin, specific cells called melanocytes, found in the basal layer of the dermis, produce melanin. Humans have a similar concentration of melanocytes in their skin, but different concentrations of skin melanin exist based on ethnicity.

[0003] Melanin plays an important biological role as a photoprotection by absorbing harmful UV radiation and converting its energy into safe heat. Due to this property, melanin can dissipate more than 99.9% of the absorbed UV radiation as heat. Melanogenesis or increased melanin production in human skin is promoted by UVB-radiation and causes a phenomenon commonly known as sunburn. The appearance of sunburn is desired by some people in various cultures, but there are also cultures that prefer the appearance of light-colored skin. Furthermore, pigment abnormalities of melanin are perceived as cosmetic defects. Examples of these local hyperpigmentations are freckles, melasma, lentigines, post-inflammatory hyperpigmentation, age spots, and many others. What is common to all of these is the formation of hyperpigmentation that causes disorders of melanogenesis.

[0004] Therefore, various methods for reducing skin pigmentation have been developed. One of the most frequently used skin and hair whitening agents is hydroquinone, or the hydroquinone glycoside of arbutin. However, these compounds have a cytotoxic effect on melanocytes and a stimulating effect on the skin. Another approach is the inhibition of melanin synthesis by inhibiting the pacemaker enzyme tyrosinase. For this purpose, kojic acid substances and kojic acid derivatives, such as kojic acid dipalmitate, azelaic acid, oxyresveratrol, linolenic acid, vitamin C, and ascorbic acid derivatives, such as ascorbyl phosphate and ascorbyl palmitate, are particularly used. However, these substances have high sensitivity, cause contact allergies, show inappropriate chemical stability in cosmetic formulations, or have only adverse effects on the skin.

[0005] Furthermore, methods for inhibiting the transfer of melanin from melanocytes to surrounding keratinocytes are also known. Thus, protease inhibitors are evaluated to inhibit the PAR2 receptor on the surface of keratinocytes, and as a result, inhibit the transfer of melanin. Hydrolysates from soybeans and niacinamide are said to reduce pigmentation in this way.

[0006] An increase in skin regeneration is also evaluated as skin lightening. In this process, alpha-hydroxy acids, such as lactic acid and glycolic acid in particular, are used. By this treatment, the uppermost skin layer is corroded and melanin-containing keratinocytes are reduced. The disadvantage of this method is that it causes a lot of skin irritation.

[0007] Therefore, there is an increasing need for new and further improved compositions for reducing the production of melanin in the skin and treating hyperpigmentation. Furthermore, compositions for cosmetically whitening skin with a relatively wide range of pigmentation have been needed for many years.

[0008] The inventors have obtained an evaluation by creating a canola extract having a high level of phenolic acids that meets these long - standing product requirements. The object of the present invention is to provide a care active ingredient having a skin whitening effect and showing good tolerance.

Summary of the Invention

[0009] Unsatisfied requirements regarding compositions and methods for reducing melanin production in the skin and treating hyperpigmentation are solved by the compositions and methods of the exemplary embodiments described herein.

[0010] In one aspect, a method for whitening the skin is provided. The method includes identifying a location on the skin where whitening or brightening is desired and topically applying to the skin a composition comprising (a) a skin whitening agent containing canola extract and (b) a cosmetically acceptable carrier.

[0011] In another aspect, a method for treating hyperpigmentation is provided. The method includes identifying a location on the skin where hyperpigmentation has occurred and topically applying to the skin a composition comprising (a) canola extract and (b) a cosmetically acceptable carrier.

Brief Description of the Drawings

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Mode for Carrying Out the Invention

[0013] In the following detailed description of exemplary embodiments, it will be understood that these embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, that other embodiments may be used, and that logical structures and chemical changes may be made without departing from the technical scope of the invention. To avoid details not necessary for enabling those skilled in the art to practice the embodiments described herein, descriptions of well-known information are omitted. Thus, the following detailed description is not to be taken in a limiting sense, and the technical scope of the exemplary embodiments is defined only by the appended claims.

[0014] The present invention provides a method for whitening the skin. The method includes identifying a location on the skin where whitening or skin brightening is desired and topically applying to the skin a composition comprising a skin whitening agent, where the whitening agent comprises a canola extract containing a high level of phenolic acids, such as sinapic acid.

[0015] In another aspect, a method for treating hyperpigmentation is provided. The method includes identifying a location on the skin where hyperpigmentation has occurred and topically applying to the skin (a) one or more of protocatechuic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, sinapic acid, and (b) a cosmetically acceptable carrier.

[0016] High phenolic acid canola composition In a preferred embodiment, the canola extract comprises one or more of protocatechuic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, sinapic acid.

[0017] In another preferred embodiment, the canola extract is selected from the group consisting of total phenols, phenolic acids, carotenoids, tocopherols / sterols, glucosinolates, and combinations thereof. In one embodiment, the combination is glucosinolate and phenol.

[0018] The canola extract can be incorporated into the formulation in an amount to provide a concentration effective for skin whitening. The concentration can be, for example, from about 0.01 μg / ml to about 10,000 μg / ml. This range should not be understood as a limitation that enables a person skilled in the art to determine an efficient concentration range for providing the desired effect. The present invention is intended to cover any concentration of at least one canola extract that exhibits a skin whitening effect.

[0019] In one embodiment, the canola extract composition contains an amount of tocopherols / sterols at a concentration to provide, for example, from about 0.1 μg / ml to about 500 μg / ml, from about 25 μg / ml to about 250 μg / ml, or from about 100 μg / ml to about 200 μg / ml.

[0020] In one embodiment, the canola extract composition contains an amount of phenolic acid at a concentration to provide, for example, from about 0.1 μg / ml to about 1000 μg / ml, from about 125 μg / ml to about 600 μg / ml, from about 250 μg / ml to about 600 μg / ml, or from about 400 μg / ml to about 600 μg / ml.

[0021] In one embodiment, the canola extract composition contains an amount of glucosinolate / phenol at a concentration to provide, for example, from about 0.1 μg / ml to about 1000 μg / ml, from about 10 μg / ml to about 600 μg / ml, from about 150 μg / ml to about 600 μg / ml, or from about 300 μg / ml to about 600 μg / ml.

[0022] In one aspect, the canola extract composition contains sinapic acid in an amount to provide a concentration of, for example, from about μg / ml to about 500 μg / ml, from about 10 μg / ml to about 400 μg / ml, or from about 40 μg / ml to about 200 μg / ml.

[0023] In embodiments where the canola extract contains glucosinolates, the glucosinolates include progoitrin, sinigrin, glucoraphanin, napoleferrin, glucoalyssin, glucobrassicanapin, 4-hydroxybrassicin, glucobrassicin, glucobrassicin, glucoraphenin, 4-methoxy-glucobrassicin, neoglucobrassicin, and combinations thereof.

[0024] In one aspect, the present invention relates to a canola extract containing at least 30% sinapic acid, preferably at least 40% sinapic acid, and most preferably at least 50% sinapic acid.

[0025] In one aspect, the present invention relates to a canola extract containing from about 40% to about 60% sinapic acid, or from about 45% to about 55% sinapic acid.

[0026] In one aspect, the present invention relates to a topical pharmaceutical preparation comprising a canola extract containing more than 30% sinapic acid, more than 40% sinapic acid, more than 50% sinapic acid, and a pharmaceutically acceptable carrier suitable for topical administration.

[0027] In one aspect, the present invention relates to a topical pharmaceutical preparation comprising a canola extract containing from about 40% to about 60% sinapic acid, or from about 45% to about 55% sinapic acid, and a pharmaceutically acceptable carrier suitable for topical administration.

[0028] In one aspect, the present invention relates to a topical pharmaceutical preparation comprising an amount of canola extract to provide from about 0.1% to about 5%, from about 0.2% to about 2.5% sinapic acid, or from about 0.4% to about 0.8% sinapic acid, and a pharmaceutically acceptable carrier suitable for topical administration.

[0029] In one aspect, the present invention relates to a topical pharmaceutical composition comprising about 0.1% to about 5% caffeic acid, about 0.2% to about 2.5% caffeic acid, or about 0.4% to about 0.8% caffeic acid, and a pharmaceutically acceptable carrier suitable for topical administration.

[0030] In one aspect, the topical pharmaceutical composition of the present invention is selected from solutions, suspensions, emulsions, lotions, ointments, gels, creams or oils.

[0031] In one aspect, the present invention relates to a transdermal delivery system comprising a transdermal delivery device and a topical pharmaceutical composition as disclosed herein. In one aspect, the transdermal delivery system is selected from transdermal patches, transdermal wet dressings, transdermal disks, and iontophoretic transdermal devices.

[0032] In one aspect, the present invention relates to a topical sunscreen composition comprising a sunscreen agent, a canola extract, and a pharmaceutically acceptable carrier suitable for topical administration.

[0033] In the topical sunscreen composition of the present invention, the sunscreen agent can be selected from the group consisting of oxybenzone, sulisobenzone, dioxybenzone, methyl anthranilate, para-aminobenzoic acid (PABA), octyl methoxycinnamate, octocrylene, drometrizole trisiloxane, octyl salicylate, homomenthyl salicylate, octyl dimethyl PABA, TEA salicylate, butyl methoxydibenzoylmethane (avobenzone), 4-methylbenzylidene camphor, 3-benzylidene camphor, benzylidene camphor sulfonic acid, octyl triazone, terephthalylidene dicamphor sulfonic acid, ethyl PABA, hydroxymethylphenyl benzotriazole, methylene bis-benzotriazolyl tetramethylbutylphenol, diethylhexyl-2,6-naphthalate, di-t-butyl hydroxybenzylidene camphor, bis-ethylhexyloxyphenol methoxyphenol triazine, titanium dioxide, zinc oxide, and any mixture thereof.

[0034] The exact amount of the sunscreen agent used in the composition can be based on the desired degree of protection from the UV radiation of the sun. In certain embodiments, the sunscreen agent is present at up to about 70% by weight, about 0.05% to about 50% by weight, or about 0.5% to about 30% by weight, based on the total weight of the formulation.

[0035] In certain embodiments, the sunscreen formulation exhibits a SPF of about 2 to about 70, or about 15 to about 45.

[0036] In certain embodiments, the present invention relates to a pharmaceutical formulation comprising a canola extract comprising at least 30% sinapic acid, preferably at least 40% acid, most preferably at least 50% sinapic acid, and a pharmaceutically acceptable excipient.

[0037] In certain embodiments, the present invention relates to an oral pharmaceutical formulation comprising a canola extract comprising about 40% to about 60% sinapic acid, or about 45% to 55% sinapic acid, and a pharmaceutically acceptable excipient.

[0038] In certain embodiments, the oral pharmaceutical formulation is in the form of a liquid, tablet, capsule, gelcap, or powder.

[0039] The canola extract of the present invention can be incorporated into the formulations of the present invention in an amount to provide the desired pharmacodynamic effect (i.e., a growth inhibitory effect or an anti-dyslipidemia effect). The concentration can be, for example, about 0.01 to about 10000 μg / ml. This range is not to be construed as a limitation as a range that enables one of ordinary skill in the art to determine an effective concentration range to provide the desired effect.

[0040] In certain embodiments, the composition of the canola extract contains a dosage of phenolic acids to provide a concentration of about 0.1 to about 1000 μg / ml, about 125 to about 600 μg / ml, about 250 to about 600 μg / ml, or about 400 to about 600 μg / ml.

[0041] In one embodiment, the canola extract composition contains a dose of sinapic acid to provide a concentration of, for example, from about 1 to about 500 μg / ml, from about 10 to about 400 μg / ml, or from about 40 to about 200 μg / ml.

[0042] In one embodiment, the pharmaceutical composition of the present invention reduces elevated lipoproteins by about 25% or more, about 50% or more, or about 75% or more, based on the requirements of the individual patient.

[0043] In one embodiment, the canola extract of the present invention can be further administered in combination with another compound capable of lowering the blood concentration of triglycerides, cholesterol, or glycerol, which compounds include, but are not limited to, fibrates (such as bezafibrate, gemfibrozil, clofibrate), HMG - COA reductase inhibitors (such as somatostatin, pravastatin, simvastatin, fluvastatin, atorvastatin, lovastatin), bile acid binding resins (such as cholestyramine and colestipol), nicotinic acid compounds (such as nicotinic acid and nicertol), fish oil. The additional compound can be administered prior to, together with, or after the canola extract.

[0044] The present invention can be administered intravenously, intraperitoneally, subcutaneously, intramuscularly, subarachnoidally, orally, sublingually, into the mouth, rectally, topically or by spraying.

[0045] Formulations suitable for oral administration include liquid solutions of the active compound dissolved in a diluent such as saline, water, or PEG400, capsules or tablets each containing a predetermined amount of the active agent as a solid, granules or gelatin, suspensions in an intermediate medium, and emulsions.

[0046] Formulations suitable for parenteral administration include aqueous and non - aqueous isotonic sterile solutions, which include neutralizing agents, antioxidants, and preservatives. The formulations may be present in single - dose or multi - dose sealed containers.

[0047] In one aspect, the compounds of the invention can be administered by topical methods, such as direct injection of the compound into the desired location, often as a depot injection or sustained release formulation.

[0048] In the case of topical administration or selective uptake, the effective local concentration of the drug may not be related to the plasma concentration.

[0049] In one aspect, the invention relates to a method for extracting phenolic acids from canola food, which comprises (a) homogenizing the canola food and (b) drying the homogenized mixture (e.g., by evaporation or lyophilization).

[0050] In one aspect, the canola food is homogenized in methanol: water at a ratio of 5:5 to 9:1, preferably about 7:3.

[0051] In one aspect, the invention relates to a method for extracting phenolic acids from canola food, which comprises (a) mixing a canola food containing phenolic acid esters in a solvent, (b) hydrolyzing the phenolic acid esters with a base, (c) acidifying the mixture, and (d) lyophilizing the mixture to obtain an extract.

[0052] In one aspect, the invention relates to a method for extracting phenolic acids from canola food, which comprises (a) mixing a canola food containing phenolic acid esters in a solvent, (b) hydrolyzing the phenolic acid esters with a base, (c) acidifying the mixture, and (d) extracting the phenolic acids with a second solvent consisting essentially of ethyl acetate.

[0053] In one aspect, the solvent contains methanol: water at a ratio of 5:5 to 9:1, preferably about 7:3.

[0054] In one aspect, the base can be an organic or inorganic base or an alkali agent such as sodium carbonate, sodium bicarbonate, disodium phosphate, trisodium phosphate, sodium citrate, magnesium hydroxide, magnesium carboxylate, calcium carboxylate, calcium phosphate, sodium hydroxide, phosphoric acid, potassium phosphate, and mixtures thereof. A preferred base is sodium hydroxide.

[0055] In one aspect, the present invention further includes extracting phenolic acid with an alkyl acrylate (preferably ethyl acetate) after acidification and suspending the extract in a second solvent before freeze-drying. Preferably, the second solvent is methanol.

[0056] In one aspect, the present invention further includes washing the freeze-dried extract with a third solvent. Preferably, the third solvent is hexane. In yet another aspect, the extract is filtered and dried, for example, by evaporation.

[0057] In one aspect, the acidification step is at a pH less than 5, preferably about 2. The acidification step can be carried out with any suitable organic or inorganic acidic material such as inorganic acids like hydrogen chloride, hydrogen bromide, nitric acid, carbonic acid, bicarbonic acid, phosphoric acid, monohydrogen phosphate, dihydrogen phosphate, sulfuric acid, monohydrogen sulfate, hydroiodic acid, or phosphorous acid; and organic acids like acetic acid, propionic acid, isobutyric acid, maleic acid, malonic acid, benzoic acid, succinic acid, suberic acid, fumaric acid, mandelic acid, phthalic acid, benzenesulfonic acid, p-tricarboxylic acid, citric acid, tartaric acid, methanesulfonic acid.

[0058] Therefore, among others, substances such as kojic acid, and derivatives of kojic acid such as kojic dipalmitate, azelaic acid, oxyresveratrol, linolenic acid, vitamin C, and derivatives of ascorbic acid such as ascorbyl phosphate or ascorbyl palmitate are used. However, these substances have high sensitivity, cause contact allergies, show inappropriate chemical stability in cosmetic formulations, or have only unsatisfactory effects on the skin.

[0059] The composition of the present invention is market - acceptable and can use common vehicles, which act as diluents, dispersants and / or carriers for the skin whitening agents and additives described herein, and any other optional but many preferred components. Thus, cosmetically acceptable vehicles suitable for use in the present invention may be aqueous, anhydrous or emulsions, whereby water - in - oil or oil - in - water emulsions are usually preferred. If the use of water is desirable, water typically constitutes the balance of the cosmetic composition and preferably constitutes from about 5% to about 99%, most preferably from about 40% to about 80% by weight of the cosmetic composition, including all ranges encompassed within the following ranges.

[0060] In addition to water, organic solvents can optionally be included in the cosmetic composition of the present invention to act as carriers or to assist carriers. Exemplary but non - limiting examples of types of organic solvents suitable for use in the present invention include alkanols such as ethyl and isopropanol alcohol, and mixtures thereof, etc.

[0061] Other optional additives suitable for use include ester oils such as isopropyl myristate, cetyl myristate, 2 - octyldodecyl myristate, avocado oil, almond oil, olive oil, neopentyl glycol dicaprylate, and mixtures thereof, etc.

[0062] Softening agents can also be used as carriers in the cosmetic composition of the present invention. Alcohols such as 1 - hexadecanol (i.e., cetyl alcohol) are often desired as softening agents which are usually classified as silicone oils and synthetic esters. Suitable silicone oils for use include cyclic or linear polydimethylsiloxanes containing 3 to 9 silicon atoms. Non - volatile silicone oils useful as softening agent materials in the cosmetic composition of the present invention described herein include polyalkylsiloxanes, polyalkylarylsiloxanes, polyethersiloxane copolymers.

[0063] Optionally usable ester plasticizers are: (1) alkenyl or alkyl esters of fatty acids having 10 to 20 carbon atoms. Examples thereof are isoarachidyl neopentanoate, isononyl isononanoate, oleyl myristate, oleyl stearate, oleyl oleate, (2) ether-esters, such as fatty acid esters of ethoxylated fatty alcohols, (3) polyhydric alcohol esters. Ethylene glycol mono- and di-fatty acid esters, diethylene glycol mono- and di-fatty acid esters. Polyethylene glycol (200-6000) mono- and di-fatty acid esters, propylene glycol 2000 monostearate, ethoxylated propylene glycol monostearate, glyceryl mono- and di-fatty acid esters, polyglycerol polyfatty acid esters, ethoxylated glyceryl monostearate, 1,3-butylene glycol monostearate, 1,3-butylene glycol distearate, polyoxyethylene polyol fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters are satisfactory polyhydric alcohol esters. (4) Wax esters, such as beeswax, spermaceti wax, stearyl stearate, arachidyl behenate, (5) sterol esters, especially cholesterol fatty acid esters are examples thereof.

[0064] When used, the plasticizer can include about 0.1% to about 50% by weight of the cosmetic composition, including all ranges subsumed within the following ranges.

[0065] Fatty acids can be included in the composition of the present invention as a cosmetically acceptable carrier. Examples of such fatty acids include pelargonic acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleonic acid, linoleic acid, arachidic acid, behenic acid, or erucic acid, and mixtures thereof. Compounds that enhance skin penetration, such as dimethyl sulfoxide, can also be used.

[0066] A polyhydric alcohol-based humectant can also be used in the cosmetic composition of the present invention. Humectants often promote an increase in the efficiency of softeners, reduce scaling, facilitate the removal of accumulated cutin, and improve skin feel. Typical polyhydric alcohols include glycerol, polyalkylene glycols, more preferably alkylene glycols and their derivatives, and include propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol and its derivatives, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1,3-butylene glycol, 1,2,6-hexanetriol, ethoxylated glycerol, propoxylated glycerol and mixtures thereof. For the best results, the humectant is preferably propylene glycol or sodium hyaluronate. The amount of the humectant is about 0.2 to about 25%, preferably about 0.5 to about 15% of the weight of the cosmetic composition, including all ranges included within the following ranges based on the total weight of the cosmetic composition.

[0067] A thickener can also be used as part of a cosmetically acceptable carrier in the cosmetic composition of the present invention. Typical thickeners include cross-linked acrylates (such as Carbopol 982), hydrophobically modified acrylates (such as Carbopol 1382), cellulose derivatives, and natural gums. Among the useful cellulose derivatives are sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose, ethyl cellulose, and hydroxymethyl cellulose. Natural gums suitable for the present invention include guar, xanthan, sclerotium particles, carrageenan, pectin, and combinations of these gums. The amount of the thickener is 0.0 to 5% by weight, usually 0.001 to 1%, and optimally 0.01 to 0.5%.

[0068] Overall, water, solvents, silicones, esters, fatty acids, humectants and / or thickeners constitute a cosmetically acceptable carrier in an amount of 1 to 99.5% by weight, preferably 80 to 99%.

[0069] Surfactants can also be present in the cosmetic compositions of the present invention. The total concentration of the surfactant ranges from about 0% to about 40%, preferably from about 0% to about 20%, and most optimally from about 0% to about 5% of the weight of the composition. The surfactant can be selected from the group consisting of anionic, nonionic, cationic, and amphoteric actives. Particularly preferred nonionic surfactants are C.sub.10-C.sub.20 fatty alcohols or acid hydrophobes concentrated with 2 to 100 moles of ethylene oxide or propylene oxide per mole of hydrophobe; mono- and di-fatty acid esters of ethylene glycol; fatty acid monoglycerides; sorbitan, mono- and di-C.sub.8-C.sub.20 fatty acids; block copolymers (ethylene oxide / propylene oxide); polyoxyethylene sorbitan, and surfactants having combinations thereof. Alkyl polyglycosides and saccharide fatty amides (e.g., methyl glucamide) are also suitable for nonionic surfactants.

[0070] Preferred anionic surfactants include soaps, alkyl ether sulfates and sulfonates, alkyl sulfates and sulfonates, alkyl benzene sulfonates, alkyl and dialkyl sulfosuccinates, C.sub.8-C.sub.20 acrylisethionates, acrylglycinates, C.sub.8-C.sub.20 alkyl ether phosphates, and combinations thereof.

[0071] Fragrances can also be used in the cosmetic compositions of the present invention. Examples of types of fragrances that can be used in the present invention, but are not limiting, include myrcene, dihydromyrcenol, citral, tagetone, cis-geleric acid, citronellic acid, mixtures thereof, and the like. Preferably, the amount of fragrance used in the cosmetic compositions of the present invention ranges from about 0.0% to about 10%, more preferably from about 0.00001% to about 5% by weight, and most preferably from about 0.0001% to about 2%.

[0072] Various types of optional additional active ingredients can be used in the cosmetic compositions of the present invention. An active is defined as a substance beneficial to the skin other than emollients and other than ingredients that merely improve the physical properties of the composition. Without limiting to this category, general examples include talc, silica, alpha-hydroxy acids, beta-hydroxy acids, zinc salts.

[0073] Beta-hydroxy acids include, for example, salicylic acid. Zinc pyrithione is an example of a zinc salt useful in the cosmetic compositions of the present invention.

[0074] Many cosmetic compositions, especially those containing water, should be protected from the growth of potentially harmful microorganisms. Thus, antibacterial compounds such as triclosan and preservatives are typically required. Suitable preservatives include p-hydroxybenzoic acid, hydantoin derivatives, propionates, various quaternary ammonium compounds. Particularly preferred preservatives in the present invention are methylparaben, propylparaben, phenoxyethanol, benzyl alcohol. Preservatives will usually be used in an amount in the range of about 0.1% to about 2% by weight of the cosmetic composition.

[0075] Still other optional ingredients that can be used in the cosmetic compositions of the present invention include diacids (such as malonic acid, sebacic acid), antioxidants such as vitamin E, retinoids (including retinoic acid, retinal, retinol and retinyl esters), conjugated linoleic acid, petroselinic acid, and mixtures thereof, and any other common ingredients well known for reducing wrinkles, anti-acne effects, and reducing the effects of sebum.

[0076] Other optional ingredients that can be used in the cosmetic composition of the present invention and that are skin whitening sources in addition to the skin whitening additives described herein. Examples of skin whitening sources that can be used in combination with the skin whitening additives of the present invention, but which are not limiting, are niacinamide, vitamin C and its derivatives, 12-hydroxystearic acid, resorcinol and its derivatives (including those esterified with, for example, ferulic acid, vanillic acid, etc.), kudzu, chamomile, extracts of sawtooth eryngo, and mixtures of any skin whitening source in addition to the skin whitening additive.

[0077] The cosmetic composition of the present invention is mainly intended to be used as a product for topical application to human skin, particularly as a product for at least skin whitening. Thus, the inventor has discovered that the described additives unexpectedly have skin whitening ability, and thereby the additives can be used as skin whitening additives in topical cosmetic compositions applied to skin areas where whitening or brightening is desired. Other advantages obtainable from the use of the cosmetic composition of the present invention can include skin moisturization, reduction of the sebum effect on the skin, and reduction of skin wrinkles. Often, the cosmetic composition of the present invention has a melting point of about 30 degrees Celsius to about 45 degrees Celsius, including all ranges encompassed within the following ranges. In a particularly preferred embodiment, the cosmetic composition of the present invention has a pH of about 4.5 to about 7.5, including all ranges encompassed within the following ranges.

[0078] From the foregoing description, it will be apparent that many advantages are provided by the present invention. Although the present invention has been shown in only a few forms, this is not merely a limitation, and various changes and modifications can be made without departing from its technical scope.

[0079] Example 1 Cell culture NHEM (Normal Human Epidermal Melanocytes) obtained from PromoCell were cultured according to the supplier's instructions. Briefly, the cells were maintained in M2 (Melanocyte Complete Growth Medium, PromoCell) supplemented with 10% FBS at 37 °C and 5% CO2 in a humidified chamber. The cells were 5 seeded at 1 × 10 5 cells / well (1 ml of 1 × 10 5 cells / ml) in a 12-well tissue culture plate (3 wells per concentration) and cultured overnight to allow the cells to attach to the plate surface. Initial measurements of melanin concentration were taken using a spectrophotometer at a wavelength of 475 nm.

[0080] Cell Treatment, Well Harvesting, and Melanin Assay A high-phenolic acid canola extract (which the inventors refer to as Dermytol™) compound was weighed and prepared immediately before use by dissolving it in distilled water at a concentration of 10 mg / mL of Dermytol™, resulting in the following: [Table 1]

[0081] A 2 mg / mL solution of Dermytol™ was prepared using the complete medium prepared for NHEM cells and sterilized using a 0.2 μm syringe filter. Serial dilutions were prepared in the medium and cells were treated at the following concentrations: 125 μg / mL, 62.5 μg / mL, 31.3 μg / mL, 15.6 μg / mL, 7.8 μg / mL. The media control received only the complete medium.

[0082] After overnight culture, the cells were treated with the media control and the test substances. Each concentration was plated in triplicate wells. The wells were cultured at 37 °C and 5% CO2 in a humidified chamber for 6 days, after which the wells were washed with PBS, trypsinized, and live cells were counted using trypan blue in a hemocytometer. The cell suspension was centrifuged and the pellet was dissolved in 1 N NaOH. Melanin concentration was determined by measuring the optical density at 475 nm.

[0083] The melanin standard curve was created by dissolving melanin (Sigma) in various dilutions in NaOH (1N) and measuring the absorbance at 475 nm using an effective spectrometer.

[0084] The resulting data was graphed for melanin production in the culture wells (area) per day for MPT by comparison with the medium control.

[0085] Results As shown in Table 1 below, an increase in the concentration of Dermytol (trade name) resulted in an increase in the inhibition of NHEM cell proliferation.

Table 2

[0086] Figure 1 further shows the effect of Dermytol (trade name) on the inhibition of NHEM cell proliferation after 6 days of culture. This graph shows that at a higher concentration (125 μg / mL), there is an 88.89% inhibition of NHEM cell proliferation. However, at concentrations of 62.5 μg / mL to 7.8 μg / mL, a dose-dependent inhibition is evident.

[0087] Table 2 shown below represents the data for melanin production per day per culture area for the treatment (MPT).

Table 3

[0088] Figure 2 further shows the effect of Dermytol (trade name) on melanin production by NHEM cells after 6 days of culture (MPT).

[0089] The biological and cosmetic effects of melanin in vivo are determined by the melanin content per area, rather than per cell. For this reason, for the evaluation of changes in melanin content after in vivo treatment, the melanin content per area (culture) is a better parameter than the melanin content per cell (Dan-Ning, et al. Methodology for evaluation of melanin content and production of pigment cells in vitro. Photochem. Photobiol. May-Jun 2008;84(3):645-9). Figure 2 shows that the production of melanin per culture well per day was inversely proportional to the dose of Dermytol (trade name) treatment compared to the medium control.

[0090] Table 3 below shows the inhibition of melanin production by Dermytol (trade name) per well per day, expressed as a percentage.

Table 4

[0091] Figure 3 further shows the effect of Dermytol (trade name) on the inhibition of melanin production by NHEM cells after 6 days of treatment. This graph shows that at a concentration of 125 μg / mL, melanin production by A375 cells decreased by 80.11% compared to the control. A dose-dependent inhibition response can also be seen in Figure 3.

[0092] Collectively, these results indicate that melanin production is decreased in cells after treatment with Dermytol (trade name) at a concentration of 15.6 μm / mL. At a concentration of 15.6 μm / mL, the viability of the cells decreased by 7.56%, while melanin production was inhibited by 33.44%. At higher concentrations, the viability of the cells at 31.3 μm / mL and 62.5 μm / mL decreased by 20.89% and 44.44% respectively. Melanin inhibition was 53.16% at a concentration of 31.3 μm / mL and 67.80% at a concentration of 62.5 μm / mL.

[0093] Example 2 Cell culture A375 (skin, malignant melanoma) available from ATCC was cultured according to the supplier's instructions. Briefly, the cells were maintained in DMEM supplemented with 10% FBS at 37 °C and 5% CO2 in a humidified chamber. The cells were placed at 1×10 5 cells / flask (1 ml of 1×10 6 cells / ml) in 27 T 25 tissue culture flasks (3 flasks per concentration) and cultured overnight to allow the cells to attach to the plate surface. The initial measurement of melanin concentration was measured at a wavelength of 475 nm with a spectrophotometer.

[0094] Cell treatment, flask collection, and melanin assay A high-phenolic acid canola extract (which the inventor refers to as Dermytol™) compound was weighed and dissolved in distilled water at a concentration of 10 mg / mL of Dermytol™ to prepare it immediately before use, and the following was formed: [Table 5]

[0095] A 2 mg / mL dilution was prepared using the complete medium prepared for A375 cells and sterilized using a 0.2 μm syringe filter and syringe. Serial dilutions were prepared with the medium and cells treated at the following concentrations, namely 1000 μg / mL, 500 μg / mL, 250 μg / mL, 125 μg / mL, 62.5 μg / mL, 31.3 μg / mL, 15.6 μg / mL, 7.8 μg / mL. The medium control received only the complete medium.

[0096] After overnight culture, the cells were treated with the medium control and the test substance. Each concentration was placed in three flasks. The flasks were cultured in a humidified chamber at 37 °C and 5% CO2 for 6 days. Then, the flasks were washed with PBS, trypsinized, and the viable cells were counted with trypan blue in a hemocytometer. The cell suspension was centrifuged and the pellet was dissolved in 1N NaOH. The melanin concentration was determined by measuring the optical density at 475 nm.

[0097] A melanin standard curve was created by dissolving melanin (Sigma) in various dilutions in NaOH (1N) and measuring the absorbance at 475 nm with an effective spectrophotometer.

[0098] The resulting data were graphed for MPT to show melanin production per day in the culture flasks (area) by comparison with the medium control.

[0099] Results Table 4 below shows the count of viable cells per flask for the treatment.

Table 6

[0100] The effect of Dermytol (trade name) on the growth of A375 cells after 6 days of culture is shown in Figure 4. Figure 4 shows that at higher concentrations of Dermytol (trade name) (1000 μg / mL - 125 μg / mL), all A375 cells died. However, at concentrations of 62.5 μg / mL - 7.8 μg / mL, a dose-dependent viability is evident.

[0101] Table 5 below shows the melanin production per day per culture area for the treatment (MPT).

Table 7

[0102] Figure 5 shows the effect of Dermytol (trade name) on melanin production by A375 cells after 6 days of culture (MPT).

[0103] The biological and cosmetic effects of melanin in vivo are determined by the melanin content per area rather than per cell. For this reason, for the evaluation of changes in melanin content after in vivo treatment, the melanin content per area (culture) is a better parameter than the melanin content per cell (Dan-Ning, et al). Figure 5 shows that the production of melanin per day per culture flask was inversely proportional to the dose of Dermytol (trade name) treatment compared to the medium control.

[0104] Table 6 below shows the inhibition of the treatment per day per flask expressed as a percentage.

Table 8

[0105] Figure 6 further shows the effect of Dermytol (trade name) on the inhibition of melanin production by A375 cells after 6 days of treatment. This graph shows that at a concentration of 62.5 μg / mL, the melanin production by A375 cells decreased by 37.54% compared to the control. A dose-dependent inhibition response is also seen in Figure 6.

Claims

1. A method for whitening skin, comprising the step of identifying a location on the skin where whitening or brightening is desired and topically applying to the skin a composition comprising (a) a skin whitening agent containing canola extract and (b) a cosmetically acceptable carrier.

2. The method according to claim 1, wherein the canola extract contains protocatechuic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, and sinapic acid.

3. The method according to claim 1, wherein the canola extract contains protocatechuic acid.

4. The method according to claim 1, wherein the canola extract contains vanillic acid.

5. The method according to claim 1, wherein the canola extract contains caffeic acid.

6. The method according to claim 1, wherein the canola extract contains syringic acid.

7. The method according to claim 1, wherein the canola extract contains p-coumaric acid.

8. The method according to claim 1, wherein the canola extract contains sinapic acid.

9. The method according to claim 1, wherein the canola extract is selected from the group consisting of total phenols, phenolic acids, carotenoids, tocopherols / sterols, glucosinolates, and combinations thereof.

10. The method according to claim 9, wherein the canola extract contains glucosinolates selected from the group consisting of progoitrin, sinigrin, glucoraphanin, napoleiferin, glucoalyssin, glucobrassicanapin, glucobrassicin, glucotropaeolin, 4-methoxy-glucobrassicin, neoglucobrassicin, and combinations thereof.

11. A method for treating hyperpigmentation, comprising the step of identifying skin containing hyperpigmented areas and topically applying to the skin a composition comprising (a) canola extract and (b) a cosmetically acceptable carrier.

12. The method according to claim 11, wherein the canola extract contains protocatechuic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, and sinapic acid.

13. The method according to claim 11, wherein the canola extract contains protocatechuic acid.

14. The method according to claim 11, wherein the canola extract contains vanillic acid.

15. The method according to claim 11, wherein the canola extract contains caffeic acid.

16. The method according to claim 11, wherein the canola extract contains sinapic acid. **Claim 17** The method according to claim 11, wherein the canola extract contains p-coumaric acid. **Claim 18** The method according to claim 11, wherein the canola extract contains caffeic acid. **Claim 19** The method according to claim 11, wherein the canola extract is selected from the group consisting of total phenols, phenolic acids, carotenoids, tocopherols / sterols, glucosinolates, and combinations thereof. **Claim 20** The method according to claim 19, wherein the canola extract contains glucosinolates selected from the group consisting of progoitrin, sinigrin, glucoraphanin, napoleiferin, glucoalyssin, glucobrassicanapin, 4-hydroxybrassicin, glucobrassicin, glucorapastorin, 4-methoxy-glucobrassicin, neoglucobrassicin, and combinations thereof.

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