KR20220105965A - Composition having antioxidant and skin whitening effect and its use - Google Patents

Abstract

Disclosed are a cosmetic composition and a health food which have excellent antioxidant and skin whitening effects without side effects. A composite extract according to the present invention prepared by a composite extraction of a mixture of mung beans, Angelica dahurica, Radix Trichosanthis, Peucedani radix, Ligusticum tenuissimum, Agastache rugosa, licorice, and Artemisia iwayomogi mixed in a specific mixing ratio with a specific solvent has a greatly high flavonoid content and significantly enhanced antioxidant and whitening effects and thus is usefully used for a material (additive) for the cosmetic composition and health food. The cosmetic composition and health food according to the present invention have excellent antioxidant and skin whitening effects without side effects such as cytotoxicity.

Description

Composition having antioxidant and skin whitening effect and its use}

The present invention relates to a composition for antioxidant and skin whitening and its use, and more particularly, antioxidative and skin whitening effect comprising a complex extract of mung bean, white paper, cloth flower powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng as active ingredients. is an excellent composition, particularly a cosmetic composition and health food, and relates to a composition excellent in antioxidant and skin whitening effects without side effects.

Active oxygen introduced from outside the living body or generated in the living body causes many problems, such as accelerating aging of the living body or causing cancer. Therefore, development and research on antioxidants that inhibit oxidation by free radicals have been conducted a lot. Antioxidants are widely distributed in the animal and plant kingdoms, and many physiologically active ingredients, such as tocopherol, vitamin C, and selenium, are known in fruits and vegetables. However, antioxidant substances present in nature could not be expected to have a substantially sufficient effect when applied to the skin. Therefore, many synthetic antioxidants with excellent antioxidant power and low price are used, but their use is limited due to safety concerns such as side effects in the human body.

To have fair and fair skin is everyone's unchanging desire. Melanin is one of the pigments that make up human hair and skin color. Melanin present in the epidermis is a pigment that blocks ultraviolet rays coming from the sun's rays. When the skin is exposed to ultraviolet rays, melanin pigment is produced as a means to defend against cell damage caused by ultraviolet absorption. Therefore, excessive exposure to ultraviolet rays or melanin may be generated by α-MSH. If melanin is locally excessively generated or the physiological function of the skin is deteriorated due to aging, etc., melanin is deposited on the skin surface, causing spots, freckles, and various cause discoloration. Since melanin is finally produced during the process of metabolizing tyrosine into various substances by the action of tyrosinase, the production of tyrosinase, an enzyme that produces melanin, is inhibited or its activity is inhibited, and melanin production is reduced.

As a general known whitening ingredient, there are substances that inhibit tyrosinase enzyme activity, such as kojic acid, arbutin, and the like. By inhibiting the production of melanin pigment, it is possible not only to realize skin whitening by brightening the skin tone, but also to improve skin hyperpigmentation such as spots or freckles caused by ultraviolet rays, hormones, or heredity. However, when applied to the skin, there is a limit on the amount of use due to safety issues such as irritation and redness.

Therefore, there is an urgent need to develop a composition derived from natural products that is safe for the body and has excellent antioxidant and skin whitening activity.

Registered Patent No. 10-2138262 Registered Patent No. 10-1895412

Accordingly, the present inventors continued research to meet the needs of the prior art, and as a result, a composition obtained by complex extraction of a mixture of mung bean, white paper, turmeric powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng mixed in a specific mixing ratio with a specific solvent is a flavonoid. It was confirmed that the content was significantly higher and there was a markedly enhanced antioxidant and whitening effect, and the present invention was completed.

Accordingly, it is an object of the present invention to provide a cosmetic composition for antioxidant and skin whitening comprising a complex extract of mung bean, white paper, cloth flower powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng as active ingredients.

Another object of the present invention is to provide a health food for antioxidant and skin whitening comprising a complex extract of mung bean, white paper, cloth pollen, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng as active ingredients.

In order to achieve the above object, the present invention provides a cosmetic composition for antioxidant and skin whitening comprising a complex extract of mung bean, white paper, cloth flower powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng as active ingredients.

In the present invention, 'antioxidation' refers to inhibiting the oxidation of cells by highly reactive free radicals or reactive oxygen species according to oxidative stress caused by intracellular metabolism or the influence of ultraviolet rays. , including reducing the damage to cells by removing free radicals or reactive oxygen species.

In the present invention, 'skin whitening' refers to not only brightening skin tone by inhibiting the production of melanin pigment, but also improving skin hyperpigmentation such as spots or freckles caused by ultraviolet rays, hormones, or heredity.

In the present invention, mung bean ( Vigna radiate (L.) Wilczek) is a leguminosae crop with high sugar (50-60%) and protein (20-24%) content including dietary fiber, and high fat content (1%) ) is a low legume. Mung beans are known to contain functional ingredients such as vitamins, minerals, flavonoids and phenolic compounds. Also, with respect to mung bean, studies on the anti-inflammatory and anti-obesity activities of isoflavone, vitexin and isovitexin contained in the peel have been reported. In folklore, it has been used as an antipyretic and antidote.

White paper is a herbal name for the root part of Angelica dahurica Bentham et Hooker in the Umbrella family. The roots are light yellowish brown and enlarged. As a crude drug, one or two years old is good, but use one that does not have a flower stalk. It is an analgesic for headache, nasal congestion, and runny nose caused by influenza, and is effective for gastrointestinal disorders, prenatal and postpartum headaches, dizziness, toothache, facial neuralgia, and paralysis. It is also known to be effective against headaches, sores, venom caused by sinusitis, and skin ulcers.

Trichosanthes kirilowii is the root from which the skin of Hanultari or yellow Hanultari of the gourd family has been peeled off. It has been used for cough, asthma, sore throat, fever, and stroke.

Sikbangpung refers to the root of Peucedanum japonicum Thunberg belonging to the Umbelliferae family. In oriental medicine, it is known to be used for pain relief, suppression of convulsions and muscle spasms, paralysis due to paralysis, etc., and is used for sputum, cough, headache, antipyretic, eczema, and neuralgia.

Gobon ( Angelica tenuissima NAKAI.) is a dicotyledonous perennial plant of the Umbelliferae family, native to the deep mountains of the country. The taste of Gobon is spicy and warm, and the spicy taste has a strong divergence effect, so it is used for headaches, fever, seawater, phlegm, and runny nose caused by external sensibility, and also has the effect of stopping a headache. In addition, Gobon contains volatile essential oil, which has sedative, analgesic, antipyretic, and anti-inflammatory effects. Also, it treats painful symptoms caused by numbness in the arms and legs caused by living in a cold and humid place.

Licorice (甘草, Glycyrrhiza uralensis ) is a medicinal plant belonging to the dicotyledonous plant Rosaceae legume and has been used as a herbal medicine since ancient times. Licorice is known to have detoxification, anti-inflammatory, anti-cancer, anti-diabetic, blood sugar and abdominal fat-reducing effects, and suppression of secretion of inflammatory mediators.

Artemisia iwaymogi Kitam ( Artemisia iwaymogi Kitam) is a perennial woody plant of the Asteraceae family, also known as a heat sieve. .

In the present invention, it is preferable to prepare and use mung bean, white paper, cloth pollen, sikbangpung, gobon, gwakhyang, licorice and Korean gin in powder of 100 mesh or more.

In the present invention, complex extraction is performed by mixing powders of mung bean, white paper, cheonflower powder, sikbangpung, gobon, gwakhyang, licorice and Korean gin, and then adding an extraction solvent at 5 to 10 times the total capacity for 24 to 72 hours at room temperature. After extraction, use by filtration.

As the extraction solvent in the present invention, 65-75% methanol or 65-75% ethanol is preferably used, and most preferably 70% methanol or 70% ethanol is used. When the concentration of methanol as an extraction solvent is out of the above range, the DPPH radical scavenging activity is lowered, the total flavonoid content is lowered, and the melanin production inhibitory activity is lowered. When the concentration of ethanol is out of the above range, the total flavonoid content is lowered, and the melanin production inhibitory activity is lowered.

Upon complex extraction according to the present invention under the above conditions, the total flavonoid content is significantly improved, and the DPPH radical scavenging activity and melanin production inhibitory activity (whitening activity) are remarkably enhanced.

In the complex extract of the present invention, mung bean is 17-25% by weight, white paper is 17-25% by weight, natural flower powder is 17-25% by weight, sikbangpung is 11-15% by weight, Gobon is 11-15% by weight, Kwakhyang is 11 ~15% by weight, licorice is preferably included in 6-10% by weight and Korean ginseng in 2-5% by weight.

In the complex extract of the present invention, when mung bean, white paper, turmeric powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng are included below the above range, the total flavonoid content is insufficient, and the DPPH radical scavenging activity and melanin production inhibitory activity may be insufficient, When included in excess of the above range, human toxicity may be induced.

In the complex extract of the present invention, total flavonoids are contained in an amount of 1.8 mg CE/g or more (FIG. 2).

The DPPH radical scavenging activity (IC50) of the complex extract of the present invention is 612 ppm or less (FIG. 1).

The melanin production inhibitory activity (absorbance at 405 nm) of the complex extract of the present invention is 0.33 or less (FIG. 5).

The complex extract of the present invention is safe without cytotoxicity even at high concentration (500 ppm) (FIG. 4).

The cosmetic composition of the present invention includes a lotion such as a flexible lotion or nourishing lotion, a lotion such as a facial lotion and body lotion, a cream such as a nourishing cream, a moisture cream, an eye cream, an essence, a cosmetic ointment, a spray, a gel, a pack, a sunscreen, It may have formulations such as makeup base, liquid type, solid type or spray type foundation, powder, cleansing cream, cleansing lotion, makeup remover such as cleansing oil, cleansing agent such as cleansing foam, soap, body wash, and toilet paper.

The cosmetic composition is a fatty substance, organic solvent, solubilizer, thickening agent and gelling agent, emollient, antioxidant, suspending agent, stabilizer, foaming agent, fragrance, surfactant, water, ionic type in addition to the complex extract. or nonionic emulsifiers, fillers, sequestering and chelating agents, preservatives, vitamins, blocking agents, wetting agents, essential oils, dyes, pigments, hydrophilic or lipophilic actives, lipid vesicles or any other conventionally used in cosmetics. It may contain adjuvants commonly used in the field of cosmetology, such as ingredients.

The cosmetic composition of the present invention may contain the complex extract in an amount of 0.1 to 10% by weight based on the total weight of the composition. When the complex extract of the present invention contains less than 0.1% by weight, sufficient antioxidant and skin whitening effects cannot be expected, and when it contains more than 10% by weight, the manufacturing cost may increase.

The cosmetic composition according to the present invention has excellent antioxidant and skin whitening effects (FIGS. 1, 2, and 5).

According to another object of the present invention, the present invention provides a health food for antioxidant and skin whitening comprising a complex extract of mung bean, white paper, turmeric powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng as active ingredients.

In the present invention, 'health food' is a food prepared by adding the complex extract as a food additive to beverages, teas, spices, gum, confectionery, etc., or encapsulating, powdering, suspension, etc. It means to bring it, but unlike general drugs, it has the advantage of not having side effects that may occur when taking the drug for a long time using food as a raw material.

Since the health food of the present invention can be consumed on a daily basis, high antioxidant and skin whitening effects can be expected, so it is very useful.

When the complex extract is used as a food additive, the complex extract may be added as it is or used with other foods or food ingredients, and may be appropriately used according to a conventional method. The mixing amount of the complex extract may be suitably determined according to the purpose of its use (prevention, health or therapeutic treatment). In general, in the production of food or beverage, the complex extract of the present invention is added in an amount of 5 parts by weight or less, preferably 3 parts by weight or less, based on the raw material.

There is no particular limitation on the type of the food. Examples of food include meat, sausage, bread, chocolate, candy, snacks, confectionery, pizza, ramen, other noodles, gum, dairy products including ice cream, various soups, beverages, tea, drinks, alcoholic beverages, and vitamin complexes. and includes all health foods in the ordinary sense.

When the health food is a beverage, it may contain a sweetener or natural carbohydrate as an additional ingredient. Natural carbohydrates are monosaccharides such as glucose and fructose, disaccharides such as maltose and sucrose, and polysaccharides such as dextrin and cyclodextrin, and sugar alcohols such as xylitol, sorbitol and erythritol. As the sweetener, natural sweeteners such as taumatine and stevia extract, synthetic sweeteners such as saccharin and aspartame, and the like can be used.

The health food of the present invention includes various nutrients, vitamins, electrolytes, flavoring agents, colorants, pectic acid and its salts, alginic acid and its salts, organic acids, protective colloidal thickeners, pH adjusters, stabilizers, preservatives, glycerin, alcohol, carbonic acid It may contain a carbonation agent used in beverages, and the like.

The complex extract according to the present invention, prepared by complex extraction of a mixture of mung bean, white paper, turmeric powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng mixed in a specific mixing ratio with a specific solvent, has an extremely high flavonoid content and significantly enhanced antioxidant and whitening It is effective as a material (additive) for cosmetic compositions and health foods.

The cosmetic composition and health food according to the present invention have excellent antioxidant and skin whitening effects without side effects such as cytotoxicity.

1 is a graph of the result of analyzing the DPPH radical scavenging activity (IC50) of a complex extract according to the present invention.
Figure 2 is a graph of the result of analyzing the total flavonoid content (mg GAE / g) of the complex extract according to the present invention.
3 is a graph showing the result of analyzing the total polyphenol content (mg GAE/g) of the complex extract according to the present invention.
4 is a graph showing the cytotoxicity test results of the complex extract according to the present invention.
5 is a graph showing the results of analyzing the melanin production inhibitory activity of the complex extract according to the present invention.

The present invention is further illustrated by the following examples. These examples are for the purpose of illustrating the present invention, and the scope of the present invention should not be limited thereto.

Preparation Example: Preparation of complex extract

Mung bean, white paper, cloth flower powder, sikbangpung, gobon, gwakhyang, licorice, and haninjin were purchased dried and powdered to 100 mesh to prepare each powder.

Each powder was mixed in the same content as in Table 1 below.

Raw material Blending amount (wt%) green gram 20 blank 20 cloth flowerpot 20 windbreak 10 Gobon 10 Kwak Hyang 10 licorice 7 Injin Han 3

As the extraction solvent, 70% ethanol (Example 1), 100% ethanol (Comparative Example 1), 70% methanol (Example 2), 100% methanol (Comparative Example 2) and distilled water (Comparative Example 3) were prepared, respectively.

5 times (v/w) of an extraction solvent was added compared to the capacity of each powder mixture, and the mixture was extracted while stirring for 24 hours, and then filtered through filter paper to prepare a complex extract.

Test Example 1. Analysis of antioxidant activity of complex extracts

Antioxidant activity was analyzed by measuring DPPH radical scavenging activity.

DPPH has stable radicals and is widely used for measuring the antioxidant activity of natural materials. It can be seen that the color changes from purple to transparent with the naked eye, and it can be used as a standard to measure the inhibition of aging by free radicals generated in in vivo metabolism as well as lipid oxidation.

Specifically, 20 μl of each of the complex extract samples of Examples 1, 2, and Comparative Examples 1 to 3 were dispensed into a 96 well-plate, and a 1.5×10 ^-4 M DPPH solution (2,2-diphenyl-1) dissolved in ethanol (2,2-diphenyl-1). -picrylhydrazyl; DPPH) was added and reacted for 10 minutes, and absorbance was measured at 517 nm with a Multimicroplate reader-SpectraMax M5 (Molecular Devices, USA). The DPPH radical scavenging activity is measured by using the absorbance of the sample to which only ethanol is added as a reference value (blank) and adding the solvent of each complex extract sample as a control. The sample concentration (Inhibitory Concentration 50 (IC50) )) was calculated as the radical scavenging ability (IC50), and the results are shown in FIG. 1 . Vitamin C was used as a positive control.

As shown in Figure 1, Example 1, which is a complex extract according to the present invention, exhibited DPPH radical scavenging activity (IC50) of 305 ppm and Example 2 of 611.2 ppm, Comparative Example 1 (using an extraction solvent of 100% ethanol) ), the complex extract of 1207 ppm, Comparative Example 3 (distilled water was used as the extraction solvent) exhibited DPPH radical scavenging activity (IC50) of 1200 ppm. Therefore, it can be confirmed that the DPPH radical scavenging activity of the complex extract according to the present invention using 70% ethanol and 70% methanol as extraction solvents was significantly improved.

Test Example 2. Analysis of total flavonoid content

The total flavonoid content was measured by mixing each of the composite extract samples of Examples 1, 2, and Comparative Examples 1 to 3 with ethanol, then adding a 2% aluminum chloride solution in a 1:1 ratio and reacting for 1 hour, Absorbance was measured at 430 nm with a Multimicroplate reader-SpectraMax M5 (Molecular Devices, USA). The total flavonoid content was converted into a gallic acid content (mg) per 1 g of a sample by creating a standard curve using gallic acid of 0 to 250 μg/ml, and the results are shown in FIG. 2 .

As shown in FIG. 2, Example 1, which is a complex extract according to the present invention, showed 1.8 mg CE/g, Example 2 showed 3.2 mg CE/g, and Comparative Example 1 (using an extraction solvent of 100% ethanol) of 0.9 mg CE/g, and that of Comparative Example 3 (distilled water was used as an extraction solvent) showed 0.6 mg CE/g. Therefore, it can be confirmed that the total flavonoid content of the complex extract according to the present invention using 70% ethanol and 70% methanol as extraction solvents was significantly improved.

Test Example 3. Analysis of total polyphenol content

For measurement of the total polyphenol content, each of the complex extract samples of Examples 1, 2, and Comparative Examples 1 to 3 was dispensed in a 96-well plate, 1 N Folin-Ciocalteu (Sigma, USA) reagent was added, and 3 at room temperature After reacting for minutes, 80 μl of 10% sodium carbonate solution was added, followed by reaction for 1 hour, and absorbance was measured at 765 nm with a Multimicroplate reader-SpectraMax M5 (Molecular Devices, USA). The total polyphenol content was converted into a gallic acid content (mg) per 1 g of a sample by preparing a standard curve using gallic acid of 0 to 200 μg/ml, and the results are shown in FIG. 3 .

As shown in FIG. 2 , the composite extract according to the present invention, Example 1, was 13.6 mg CE/g, and Example 2 was 12 mg CE/g, indicating a high content of total polyphenols. In contrast, the composite extract of Comparative Example 3 (distilled water was used as an extraction solvent) showed a total polyphenol content of 9.4 mg CE/g.

Test Example 4. Cytotoxicity analysis

B16F10 cells, a malignant melanoma cell line, were cultured at 37°C, 5% using Dublecco's Modified Eagle medium (Gibco, MD, USA) containing 100 unit/ml penicillin-streptomycin and 10% fetal bovine serum (Gibco, MD, USA). CO ₂ Cultivated in an incubator, and subcultured every 2 days. For cell viability measurement, B16F10 cells were dispensed in a 96-well plate at 1×10 ⁵ cells/ml, and each of the complex extract samples of Examples 1, 2, and Comparative Examples 1 to 3 was treated with 500 ppm, followed by treatment at 37° C., 5 % CO ₂ Incubated in an incubator for 24 hours. After the addition of CellTiter 96 aqueous non-radioactive cell proliferation assay reagent (Promega, WI, USA), it was reacted for 4 hours at 37° C., 5% CO ₂ in an incubator at 490 nm using Multimicroplate reader-SpectraMax M5 (MolecularDevices, USA). The absorbance was measured to measure the cell viability, and the results are shown in FIG. 4 .

As shown in Figure 4, the complex extraction composition (Example 1, Example 2) of the present invention was confirmed to have no toxicity as a result of cell viability test.

Test Example 5. Melanin production inhibitory activity analysis

B16F10 cells, a malignant melanoma cell line, were cultured at 37°C, 5% using Dublecco's Modified Eagle medium (Gibco, MD, USA) containing 100 unit/ml penicillin-streptomycin and 10% fetal bovine serum (Gibco, MD, USA). CO ₂ Cultivated in an incubator, and subcultured every 2 days.

B16F10 cells were dispensed in a 96-well plate at 1×10 ⁵ cells/ml, and 1 μM of α-MSH (α-melanocyte stimulating hormone) and Examples 1, 2, and Comparative Examples 1 to Each of the complex extract samples of 3 was treated with 500 ppm, cultured in an incubator at 37° C., 5% CO ₂ for 3 days, and the cells were harvested by washing twice with PBS (Phosphate-buffered saline). 10% dimethyl sulfoxide (DMSO, sigma, Solon, Ohio, USA) was treated with 1 N NaOH solution to dissolve the melanin produced in the cells at 75 ℃ for 1 hour, Multimicroplatereader-SpectraMax M5 (Molecular Devices, USA) Each absorbance was measured at 405 nm using , and the results are shown in FIG. 5 . Treated only with α-MSH as a control and treated with arbutin as a positive control, tested in the same manner as above and absorbance was measured, and the results are also shown in FIG. 5 .

As shown in FIG. 5, in the control treated with α-MSH only, the absorbance was 0.54 and the amount of melanin production was more than doubled compared to the normal (0.25), whereas Example 1, which is a complex extract according to the present invention, was 0.33, Example 2 represents 0.29, and the amount of melanin production was decreased, which was close to a normal value.

In comparison, the composite extract of Comparative Example 1 (using an extraction solvent of 100% ethanol) had an absorbance of 0.58, the composite extract of Comparative Example 2 (using an extraction solvent of 100% methanol) was 0.51, and Comparative Example 3 (distilled water as the extraction solvent) The complex extract of used) showed 0.51, confirming that it showed almost the same or more melanin production than the control.

Therefore, it can be seen that the complex extract according to the present invention significantly enhances the activity of inhibiting melanin production.

Claims (8)

A cosmetic composition for antioxidant and skin whitening comprising a complex extract of mung bean, white paper, turmeric powder, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng as active ingredients.
According to claim 1, wherein the complex extract is after mixing the powders of mung bean, white paper, cheonhwabun, sikbangpung, gobon, gwakhyang, licorice and Korean ginseng, 65 to 75% methanol or 65 at a dose 5 to 10 times the total capacity. A cosmetic composition for antioxidant and skin whitening, characterized in that it is prepared by adding an extraction solvent of ~75% ethanol, extracting at room temperature for 24 to 72 hours, and then filtration.
The method according to claim 1, wherein mung bean is 17-25 wt%, white paper is 17-25 wt%, natural flower powder is 17-25 wt%, sikbangpung is 11-15 wt%, Gobon is 11-15 wt%, and Kwakhyang is 11 ~15% by weight, licorice, 6-10% by weight, and Korean ginseng 2-5% by weight of antioxidant and skin whitening cosmetic composition.
The method according to claim 1, wherein the complex extract contains total flavonoids at 1.8 mg CE/g or more, DPPH radical scavenging activity (IC50) is 612 ppm or less, and melanogenesis inhibitory activity (absorbance at 405 nm) is 0.33 or less. A cosmetic composition for antioxidant and skin whitening.
According to claim 1, wherein the cosmetic composition is a lotion, facial lotion, body lotion, nourishing cream, moisture cream, eye cream, essence, cosmetic ointment, spray, gel, pack, sunscreen, makeup base, foundation, powder, cleansing cream , cleansing lotion, cleansing oil, cleansing foam, soap, body wash, and a cosmetic composition for antioxidant and skin whitening, characterized in that any one formulation selected from the group consisting of toilet paper.
A health food for antioxidant and skin whitening that contains complex extracts of mung bean, white paper, cloth pollen, sikbangpung, gobon, gwakhyang, licorice, and Korean ginseng as active ingredients.
The method according to claim 6, wherein the complex extract is prepared by mixing powders of mung bean, white paper, cheonhwabun, sikbangpung, gobon, gwakhyang, licorice and Korean gin, 65 to 75% methanol or 65 at a dose 5 to 10 times the total capacity. A health food for antioxidant and skin whitening, characterized in that it is prepared by adding an extraction solvent of ~75% ethanol to extraction at room temperature for 24 to 72 hours, followed by filtration.
The method according to claim 6, wherein the complex extract contains total flavonoids at 1.8 mg CE/g or more, DPPH radical scavenging activity (IC50) is 612 ppm or less, and melanogenesis inhibitory activity (absorbance at 405 nm) is 0.33 or less. Antioxidant and health food for skin whitening.

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