JP5041569B2 - Tyrosinase activity inhibitor, whitening agent and skin cosmetic - Google Patents

Description

  The present invention relates to a tyrosinase activity inhibitor, whitening agent or skin cosmetic containing a plant extract as an active ingredient.

  Melanin also plays a role in protecting the body from ultraviolet rays in the skin, but overproduction and uneven accumulation cause skin darkening and spots. In general, melanin is converted from tyrosine to dopa and from dopa to dopaquinone by the action of the enzyme tyrosinase biosynthesized in pigment cells, and then formed through intermediates such as 5,6-dihydroxyindophenol. ing. Therefore, in order to prevent, treat or improve skin darkness (skin pigmentation), it is conceivable to inhibit the activity of tyrosinase involved in the production of melanin.

Conventionally, for the prevention, treatment or improvement of skin pigmentation, stains, buckwheat, etc., a treatment using a whitening agent containing a chemically synthesized product such as hydroquinone as an active ingredient has been performed. However, chemically synthesized products such as hydroquinone may cause side effects such as skin irritation and allergy. Therefore, development of a whitening agent containing a highly safe natural raw material as an active ingredient is desired. Examples of those having a tyrosinase activity inhibitory action include wisteria tea extract (see Patent Document 1), Yanagitade extract ( Patent Document 2) has been proposed.
JP 2002-370962 A JP 2004-83488 A

  An object of the present invention is to provide a tyrosinase activity inhibitor, a whitening agent, and a skin cosmetic, which have a tyrosinase activity inhibitory action among natural products and contain it as an active ingredient.

  In order to achieve the above object, firstly, the present invention is a scorpion extract, psyllium extract, calasquisan sankirai extract, psyllium extract, prunus prunus extract, fujibusa extract, katsuyamahihatsu extract, tama hydrangea It contains one or more plant extracts selected from the group consisting of an extract, a kibushi extract, a firefly black extract, a cypress extract, a malwout cedar extract and a cat extract, as an active ingredient A tyrosinase activity inhibitor is provided.

  Secondly, the present invention relates to the extraction of botanus extract, psyllium extract, calasquisan sankirai extract, psyllium extract, striped pear extract, barnacle extract, papaver extract, tuna hydrangea extract, kibushi extract, firefly black Provided is a whitening agent comprising, as an active ingredient, one or more plant extracts selected from the group consisting of an extract, a Japanese cypress extract, a bumblebee extract, and a cat extract.

  Thirdly, the present invention relates to an extract of bovine cowpea, extract of grasshopper, extract of sunflower moth, extract of psyllium, extract of shrimp, spotted pear extract, extract of beetle, extract of yellow hydrangea, extract of yellow beetle, firefly black Provided is a skin cosmetic characterized by blending one or more plant extracts selected from the group consisting of an extract, a cypress extract, a bumblebee extract, and a cat extract.

  ADVANTAGE OF THE INVENTION According to this invention, the tyrosinase activity inhibitor, whitening agent, and skin cosmetics which contain the plant extract which has the outstanding tyrosinase activity inhibitory effect as an active ingredient can be provided.

The present invention will be described below.
[Tyrosinase activity inhibitor, whitening agent]
The tyrosinase activity inhibitor or whitening agent of the present invention includes a catfish extract, a grasshopper extract, a mustard leaf extract, a psyllium extract, a striped pear extract, a pterosa extract, a corn hydrangea extract, a yellow hydrangea extract, a kibushi One or more plant extracts selected from the group consisting of an extract, a firefly extract, a Japanese cypress extract, a bumblebee extract, and a cat extract are included as active ingredients.

  Here, in the present invention, the `` extract '' is selected from the group consisting of botanicals, corn moths, calaske sankirai, psyllium serrata, simus serrata, fujiboxa, scots hawk moths, tama hydrangea, squirrels, fireflies, Japanese cypress, bumblebees, and cats Any one of an extract obtained by using one or more plants as an extraction raw material, a diluted or concentrated solution of the extract, a dried product obtained by drying the extract, or a roughly purified product or a purified product thereof Is also included.

  Extraction raw materials used in the present invention are bovine cowpea (scientific name: Vigna marina), psyllium (scientific name: Macaranga tanarium), calasquisansanrai (scientific name: Heterosmilax japonica), psyllium (scientific name: Ficus caulocarpa), shimasarnashi (scientific name: Actinidia rufa) , Fujibogusa (scientific name: Uraria crinita), Kotoyamahihatsu (scientific name: Antisma pentandrum), Tama hydrangea (scientific name: Hydrangea involucrata), Kibushi (scientific name: Stachyurus praecox), firefly bukuro (scientific name: Campanula punctata), sumnoty (scientific name) ), Malbautsugi (scientific name: Deutzia scabra) or cats (scientific name: Lespedeza pilosa). When using two or more kinds of plants as an extraction raw material, the above plants can be used in any combination.

  The Vigna marina (Vigna marina) is a perennial vine belonging to the genus Leguminosae that lives on the coast from the Nansei Islands to the tropics, and can be easily obtained from these regions. Examples of the part that can be used as the raw material for extraction include the above-ground part, root part, whole plant, and the like, and the whole part is preferable.

  The above-mentioned Oba (Macaranga tanarium) is an evergreen small tree that belongs to the Euphorbiaceae, which grows naturally in the Nansei Islands and can be easily obtained from these areas. Examples of the part that can be used as the extraction raw material include a trunk, an above-ground part, a root part, and a whole plant, and a trunk part is preferable.

  The above-mentioned Karasukibasankirai (Heterosmilax japonica) is a vine semi-shrub belonging to the genus Karasukibasankirai, which is distributed in the Nansei Islands, the southern part of the mainland of China, the Indochina Peninsula, etc. Can do. Examples of the part that can be used as the extraction raw material include the above-ground part, root part, whole grass, and the like, and the root part is preferable.

  The above-mentioned psyllium (Ficus caulocarpa) is a tree belonging to the genus Asteraceae distributed in the tropics and the like, and can be easily obtained from these regions. Examples of the part that can be used as the raw material for extraction include a leaf part, an above-ground part, a root part, and a whole plant, and a leaf part is preferable.

  The above-mentioned Actinidia rufa is a tree or shrub belonging to the genus Matatabidae, which is distributed near the coast of Honshu Kii Peninsula, Yamaguchi Prefecture, Shikoku, Kyushu, Nansei Islands, Korean Peninsula, etc. It can be easily obtained. Examples of the part that can be used as the extraction raw material include a stem part, an above-ground part, a root part, and a whole plant, and a stem part is preferable.

  The above-mentioned Uraria crinita is a woody perennial belonging to the genus Legumeaceae distributed in regions such as the tropics, and can be easily obtained from these regions. Examples of the part that can be used as the extraction raw material include the above-ground part, root part, whole grass, and the like, and the root part is preferable.

  The above-mentioned Anthisma pentandrum is an evergreen shrub belonging to the genus Amaranthaceae, which grows naturally in the Okinawa Islands and the Yaeyama Islands, and is distributed from Taiwan to the Philippines. It can be obtained. Examples of the part that can be used as the extraction raw material include a trunk, an above-ground part, a root part, a whole plant, and the like, and a trunk part is preferable.

  The above-mentioned Hydrangea involucrata is a deciduous shrub belonging to the genus Hydrangea, which is distributed in areas such as Honshu, and can be easily obtained from these areas. Examples of the part that can be used as the raw material for extraction include a leaf part, an above-ground part, a root part, and a whole plant, and a leaf part is preferable.

  The above-mentioned kibushi (Stachyurus praecox) is a deciduous shrub belonging to the genus Kibushi family in the southwestern Hokkaido, Honshu, Shikoku, Kyushu, etc., and can be easily obtained from these areas. Examples of the part that can be used as the extraction raw material include a trunk, an above-ground part, a root part, a whole plant, and the like, and preferably a trunk part or a root part.

  The above-mentioned firefly black turtle (Campanula punctata) is a perennial belonging to the genus Firefly genus, which is distributed in areas such as Hokkaido, Honshu, Shikoku, Kyushu, the Korean Peninsula, China and Siberia, and can be easily obtained from these areas. it can. Examples of the part that can be used as the raw material for extraction include the above-ground part, root part, whole plant, and the like, and the whole part is preferable.

  The above-mentioned Japanese cypress (Distylium racemosum) is an evergreen tree belonging to the genus Hyacinthaceae that is distributed in regions such as Honshu, Shikoku, Kyushu, Okinawa, Taiwan, China, etc. in Japan, and can be easily obtained from these regions. it can. Examples of the part that can be used as the extraction raw material include a leaf part, a trunk part, an above-ground part, a root part, and a whole plant, and a leaf part, a trunk part, or a root part is preferable.

  The above-mentioned Deutzia scabra is a deciduous shrub belonging to the genus Udonidae, which is distributed in areas such as Honshu, Shikoku, and Kyushu west of the Kanto region, and can be easily obtained from these areas. Examples of the part that can be used as the extraction raw material include a trunk, an above-ground part, a root part, and a whole plant, and a trunk part is preferable.

  The above-mentioned cats (Lespedeza pilosa) are perennials belonging to the genus Leguminosae which are distributed from Honshu to Ryukyu Islands, the Korean Peninsula, China and other regions, and can be easily obtained from these regions. Examples of the part that can be used as the extraction raw material include the above-ground part, root part, whole grass, and the like, and the above-mentioned part is preferable.

  Although the details of the substance having an inhibitory activity on tyrosinase contained in the extract from the plant are not clear, an extract having an inhibitory activity on tyrosinase activity is extracted from each plant by an extraction method generally used for the extraction of plants. Obtainable.

  For example, after drying the plant, it is pulverized as it is or using a crusher, and subjected to extraction with an extraction solvent, whereby an extract having an inhibitory effect on tyrosinase activity can be obtained. Drying may be performed in the sun or using a commonly used dryer. Moreover, after performing pretreatment, such as degreasing, with a nonpolar solvent such as hexane, it may be used as an extraction raw material. By performing pretreatment such as degreasing, extraction with a polar solvent can be performed efficiently.

  As the extraction solvent, it is preferable to use a polar solvent, and examples thereof include water and hydrophilic organic solvents. These may be used alone or in combination of two or more at room temperature or a temperature below the boiling point of the solvent. Is preferred.

  Examples of water that can be used as the extraction solvent include pure water, tap water, well water, mineral spring water, mineral water, hot spring water, spring water, fresh water, and the like, and those subjected to various treatments. Examples of the treatment applied to water include purification, heating, sterilization, filtration, ion exchange, osmotic pressure adjustment, buffering, and the like. Therefore, the water that can be used as the extraction solvent in the present invention includes purified water, hot water, ion-exchanged water, physiological saline, phosphate buffer, phosphate buffered saline, and the like.

  Examples of hydrophilic organic solvents that can be used as the extraction solvent include lower aliphatic alcohols having 1 to 5 carbon atoms such as methanol, ethanol, propyl alcohol, and isopropyl alcohol; lower aliphatic ketones such as acetone and methyl ethyl ketone; -C2-C5 polyhydric alcohols, such as butylene glycol, propylene glycol, and glycerol, etc. are mentioned.

  When using the liquid mixture of 2 or more types of polar solvents as an extraction solvent, the mixing ratio can be adjusted suitably. For example, when using a liquid mixture of water and a lower aliphatic alcohol, it is preferable to mix 1 to 90 parts by weight of a lower aliphatic alcohol with respect to 10 parts by weight of water. When using a mixed solution, it is preferable to mix 1 to 40 parts by mass of a lower aliphatic ketone with 10 parts by mass of water, and when using a mixed solution of water and a polyhydric alcohol, water 10 It is preferable to mix 1-90 mass parts of polyhydric alcohol with respect to mass parts.

  The extraction treatment is not particularly limited as long as the soluble component contained in the extraction raw material can be eluted in the extraction solvent, and can be performed according to a conventional method. For example, the extraction raw material is immersed in an extraction solvent 5 to 15 times (mass ratio) of the extraction raw material, the soluble components are extracted at room temperature or under reflux, and then filtered to remove the extraction residue. A liquid can be obtained. The obtained extract is diluted, concentrated, dried, purified, etc. according to a conventional method in order to obtain a diluted or concentrated solution of the extract, a dried product of the extract, or a crude purified product or a purified product thereof. Processing may be performed.

  Purification can be performed by, for example, activated carbon treatment, adsorption resin treatment, ion exchange resin treatment, or the like. The obtained extract can be used as it is as an active ingredient of a tyrosinase activity inhibitor or a whitening agent, but a concentrated solution or a dried product is easier to use.

  Since the extract from the plant has a characteristic odor and taste, it can be purified for the purpose of decolorization, deodorization, etc. within a range that does not cause a decrease in its physiological activity. Since it is not used in a large amount when it is blended, etc., there is no practical problem even if it is not purified.

  Since the extract from the plant obtained as described above has a tyrosinase activity inhibitory action, it can be used as an active ingredient of a tyrosinase activity inhibitor or a whitening agent using the action.

  The tyrosinase activity inhibitor or whitening agent of the present invention may consist only of an extract from the above plant, or may be formulated from the above extract.

  Extracts from the above plants are in any dosage form such as powder, granule, tablet, liquid, etc., using a pharmaceutically acceptable carrier such as dextrin, cyclodextrin and other optional auxiliaries according to conventional methods. In addition to being used in other compositions (for example, skin cosmetics described later), it can also be used as an ointment, an external liquid, a patch, etc. . In this case, as an auxiliary agent, for example, an excipient, a binder, a disintegrant, a lubricant, a stabilizer, a flavoring agent and the like can be used.

  The tyrosinase activity inhibitor or whitening agent of the present invention may contain any one of the extracts from plants as an active ingredient, or may contain two or more kinds in combination as an active ingredient. When two or more extracts from each plant are combined and contained as an active ingredient, the content ratio is not particularly limited, and is appropriately determined according to the strength of the physiological activity of the extract from the plant. Can be adjusted.

  The tyrosinase activity inhibitor or whitening agent of the present invention inhibits tyrosinase activity through the tyrosinase activity inhibitory action of plant extracts, and can prevent, treat, or improve skin darkening, spots, freckles, etc. it can. However, the tyrosinase activity inhibitor or whitening agent of the present invention can be used for all purposes that are meaningful in exhibiting a tyrosinase activity inhibitory action in addition to these uses.

[Skin cosmetic]
Catfish extract, Oobagi extract, Karasukisan Kirai extract, Psyllium extract, Shimasarnashi extract, Fujibusa extract, Kumayamahihatsu extract, Tuna hydrangea extract, Kibushi extract, Firefly extract, Cyprinus extract, Malbautsugi extract or cat hagi extract is suitable for blending into skin cosmetics because of its excellent usability and safety when applied to the skin. In this case, any one of the extracts from the above plant or a combination of two or more may be added, or a tyrosinase activity inhibitor or whitening agent formulated from the above extract from the plant may be added. Also good. By adding an extract from the above plant, a tyrosinase activity inhibitor or a whitening agent to the skin cosmetic, it is possible to impart an inhibitory effect on tyrosinase activity to the skin cosmetic.

  Skin cosmetics that can be blended with the above plant extract are not particularly limited, for example, ointments, creams, emulsions, lotions, packs, foundations, lip balms, bathing agents, hair arts, hair lotions, Examples include soaps and body shampoos.

  When an extract from the above plant is blended into a skin cosmetic, the blending amount can be adjusted as appropriate according to the type of skin cosmetic, but a suitable blending ratio is converted to a standard extract. About 0.0001 to 10% by mass, and a particularly suitable blending ratio is about 0.001 to 1% by mass in terms of a standard extract.

  The skin cosmetic of the present invention is a main agent, auxiliary agent or other components used in the production of ordinary skin cosmetics, such as astringents, bactericides, as long as the tyrosinase activity inhibitory action of the plant extract is not disturbed. Antibacterial agents, whitening agents, UV absorbers, moisturizers, cell activators, anti-inflammatory / antiallergic agents, antioxidant / active oxygen scavengers, fats and oils, waxes, hydrocarbons, fatty acids, alcohols, esters , Surfactants, fragrances and the like can be used in combination. When used in combination, it becomes a more general product, and a synergistic effect with other active ingredients used in combination may lead to an excellent effect that is more than normally expected.

  The tyrosinase activity inhibitor, whitening agent or skin cosmetic of the present invention is preferably applied to humans, but may be applied to animals other than humans as long as each effect is exhibited. You can also

  Hereinafter, although a manufacture example, a test example, and a compounding example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to each following example at all.

[Production Example 1] Manufacture of extracts from each plant 2 L of extraction solvent was added to 200 g of dried dried cowpeas, and the mixture was heated and extracted with a reflux extractor at 80 ° C for 2 hours. When filtered. The same extraction process was further performed on the residue. The obtained extracts were combined, concentrated under reduced pressure, and further dried to obtain a cowpea extract. Table 1 shows the yield of each extract when water, 50% by mass ethanol (mass ratio of water to ethanol = 1: 1), and ethanol were used as the extraction solvent.

  In the same manner as described above, psyllium stem, crows root, psyllium leaf, prunus stalk, pterocarp stalk, pterocarp root, pterosa terrestris, cypress hydrangea stalk, yellow hydrangea stalks, kibushi stalks, kibushi roots, firefly Extraction was performed by performing extraction treatment using roots, cypress stems, cypress leaves, cypress stems, or above-ground parts of roots. Table 1 shows the yield of each extract when water, 50 mass% ethanol, or ethanol was used as the extraction solvent.

[Test Example 1] Tyrosinase activity inhibitory action test The extracts from each plant obtained in Production Example 1 were tested for tyrosinase activity inhibitory action as follows.

  In a test tube, dissolve 0.45 mL of 1/15 M phosphate buffer (pH 6.8), 1.0 mL of 0.1 mg / mL tyrosine solution, and 40 mg of extract from each plant in 1 mL of 50 mass% ethanol. 0.05 mL of the obtained sample solution was added, 0.5 mL of tyrosinase solution (derived from mushrooms, 128.4 unit / mL, manufactured by Sigma) was further added, and the mixture was incubated at 37 ° C. for 1 hour. After completion of the reaction, the absorbance at a wavelength of 475 nm was measured. The same operation and absorbance measurement were performed using 1/15 M phosphate buffer (pH 6.8) without adding the enzyme solution. Further, the same measurement was performed for only the solvent of the sample solution without adding the sample solution. From the obtained results, the tyrosinase activity inhibition rate was calculated by the following formula.

Tyrosinase activity inhibition rate (%) = {1− (A−B) / (C−D)} × 100
In the above formula, A is “absorbance when enzyme solution is added / sample solution is added”, B is “absorbance when enzyme solution is not added / sample solution is added”, and C is “addition of enzyme solution / no sample solution is added” D "indicates" absorbance when no enzyme solution is added / sample solution is not added ".
The results of the above test are shown in Table 2.

  As shown in Table 2, the whole cowpea, the plant of a grasshopper, the root of a yellow-spotted beetle, the leaf of a grasshopper, the stem of a striped shrimp, the root of a Japanese pear, the ground of a Japanese pufferfish, the stem of the Japanese horse mackerel, the stem of a yellow hydrangea, the stem of a yellow beetle, It was confirmed that the extract from the whole firefly, the root of the cypress, the stem of the cypress, the leaf of the cypress, the stem of the cypress, or the above-ground part of the catwood has an excellent tyrosinase activity inhibitory action.

[Formulation Example 1]
An emulsion having the following composition was produced by a conventional method.
Cattle whole cow 50% ethanol extract (Production Example 1) 0.01 g
Jojoba oil 4.0g
Placenta extract 0.1g
Olive oil 2.0g
Squalane 2.0g
Cetanol 2.0g
Glyceryl monostearate 2.0g
Polyoxyethylene cetyl ether (20E.O) 2.5g
Oleic acid polyoxyethylene sorbitan (20E.O) 2.0g
1,3-butylene glycol 3.0 g
Hinokitiol 0.15g
Fragrance 0.05g
Purified water remainder (total amount is 100 g)

[Formulation Example 2]
A cream having the following composition was produced by a conventional method.
Weow trunk 50% ethanol extract (Production Example 1) 0.05 g
Karasukibasankirai root 50% ethanol extract (Production Example 1) 0.05g
Liquid paraffin 5.0g
Salami beeswax 4.0g
Cetanol 3.0g
Squalane 10.0g
Lanolin 2.0g
Stearic acid 1.0g
Oleic acid polyoxyethylene sorbitan (20E.O) 1.5g
3.0 g glyceryl monostearate
1,3-butylene glycol 6.0 g
1.5 g of methyl paraoxybenzoate
Fragrance 0.1g
Purified water remainder (total amount is 100 g)

[Composition Example 3]
A cream having the following composition was produced by a conventional method.
Psyllium leaf water extract (Production Example 1) 0.05g
50% ethanol extract of roots of Fujiboxa (Production Example 1)
Polyethylene glycol monostearate 2.0g
Self-emulsifying glyceryl monostearate 5.0 g
Stearic acid 2.0g
Cetanol 2.0g
Squalane 12.0g
Macadamia nut oil 3.0g
0.2g of methylpolysiloxane
Fragrance 0.01g
Preservative (Methyl paraoxybenzoate) 0.15g
1,3-butylene glycol 7.0 g
Xanthan gum 0.2g
Purified water remainder (total amount is 100 g)

[Formulation Example 4]
A serum having the following composition was produced by a conventional method.
Shimasarnashi stem ethanol extract (Production Example 1) 0.01 g
Xanthan gum 0.3g
Hydroxyethylcellulose 0.1g
Carboxyvinyl polymer 0.1g
1,3-butylene glycol 4.0 g
Glycerin 2.0g
Potassium hydroxide 0.25g
Fragrance 0.01g
Preservative (Methyl paraoxybenzoate) 0.15g
Ethanol 2.0g
Purified water remainder (total amount is 100 g)

[Formulation Example 5]
A serum having the following composition was produced by a conventional method.
Tama hydrangea leaf ethanol extract (Production Example 1) 0.05 g
Kibushi trunk ethanol extract (Production Example 1) 0.05 g
Carboxyvinyl polymer 0.2g
Xanthan gum 0.2g
Sodium hyaluronate 0.1g
Polyethylene glycol 3.0g
Glycerin 6.0g
1,3-butylene glycol 3.0 g
Preservative (Methyl paraoxybenzoate) 0.15g
L-Arginine 0.15g
Purified water remainder (total amount is 100 g)

[Composition Example 6]
A pack having the following composition was produced by a conventional method.
Kotoyamahihatsu trunk water extract (Production Example 1) 0.05 g
Polyvinyl alcohol 15g
Polyethylene glycol 3g
7g of propylene glycol
Ethanol 10g
0.05 g ethyl paraoxybenzoate
Fragrance 0.05g
Purified water remainder (total amount is 100 g)

[Formulation Example 7]
A cleaning lotion having the following composition was produced by a conventional method.
Firefly Bukuro whole plant 50% ethanol extract (Production Example 1) 0.05 g
Japanese cypress leaf 50% ethanol extract (Production Example 1) 0.05 g
Malbautsugi trunk 50% ethanol extract (Production Example 1) 0.05 g
1,3-butylene glycol 4.0 g
Glycerin 4.0g
Dipropylene glycol 2.0g
Polyoxyethylene polyoxypropylene
Decyl tetradecyl ether 0.7g
Ethanol 3.0g
Fragrance 0.001g
Preservative (Methyl paraoxybenzoate) 0.15g
Purified water remainder (total amount is 100 g)

[Formulation Example 8]
An emulsion having the following composition was produced by a conventional method.
Cat extract above ground ethanol extract (Production Example 1) 0.05 g
1.0 g polyoxyethylene sorbitan monostearate
Tetraoleic acid polyoxyethylene sorbit 1.5g
Lipophilic glyceryl monostearate 1.0g
Stearic acid 0.5g
Behenyl alcohol 1.5g
Cetyl palmitate 0.5g
Squalane 10.0g
Methyl polysiloxane 0.5g
Fragrance Appropriate amount Preservative (methyl paraoxybenzoate) 0.15g
1,3-butylene glycol 7.0 g
Xanthan gum 0.1g
Purified water remainder (total amount is 100 g)

The tyrosinase activity inhibitor, whitening agent, or skin cosmetic of the present invention is useful for prevention, treatment, or improvement of skin blackening, spots, buckwheat, etc. due to excessive production or uneven accumulation of melanin.

Claims (4)

It contains one or more plant extracts selected from the group consisting of extract of grass trunk, extract of red-crowned sunbill, extract of Fujibgusa, extract of Kotoyamahihatsu and firefly bukuro as an active ingredient And a tyrosinase activity inhibitor. It contains one or more plant extracts selected from the group consisting of extract of grass trunk, extract of red-crowned sunbill, extract of Fujibgusa, extract of Kotoyamahihatsu and firefly bukuro as an active ingredient Whitening agent. A skin cosmetic characterized by blending an extract of a wolf trunk and / or an extract of Karasukisankirai. A skin cosmetic for whitening, comprising one or more plant extracts selected from the group consisting of an extract of Fujiboxa, a extract of Kotoyamahihatsu and a firefly extract .