• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.874-879
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• 2008

Tyrosinase is a key enzyme for melanin biosynthesis, and hyperpigmentation disorders are associated with abnormal accumulation of melanin pigments, which can be reduced by treatment with depigmenting agents. The methanol extract of Lespedeza cyrtobotrya $M_{IQ}$ showed inhibitory activity against mushroom tyrosinase. The active compound was purified from the methanol extract of L. cyrtobotrya, followed by several chromatographic methods, and identified as dalbergioidin (DBG) by spectroscopic methods. The results showed that DBG exhibited tyrosinase inhibitory activity with an $IC_{50}$ of $20\;{\mu}M$. The kinetic analysis of tyrosinase inhibition revealed that DBG acted as a noncompetitive inhibitor. In addition, DBG showed a melanin biosynthesis inhibition zone in the culture plate of Streptomyces bikiniensis that has commonly been used as an indicator organism. Furthermore, $27\;{\mu}M$ DBG decreased more than 50% of melanin contents on the pigmentation using the immortalized mouse melanocyte, melan-a cell.

• Journal of Applied Biological Chemistry
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• v.65 no.2
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• pp.93-99
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• 2022

Lysosome organelle extract (LOE) was derived from egg whites. The lysosome is an intracellular organelle that contains several hydrolysis enzymes. Previous studies have reported that LOE performs important functions, such as melanin de-colorization and anti-melanin production in B16F10 melanoma cells. However, its principal molecular and cellular mechanisms have not been elucidated till date. In non-cytotoxic conditions, LOE significantly inhibited α-MSH induced melanin synthesis of murine B16F10 cells. The anti-melanogenic activity of LOE was mediated by suppressing the mRNA expression of tyrosinase enzyme, tyrosinase related protein-1/2 (TRP-1/2), and microphthalmia-associated transcription factor (MITF) genes. By performing western blot analysis, we found that LOE significantly attenuated melanogenesis. In this case, LOE helped in increasing extracellular receptor kinase (ERK) phosphorylation in α-MSH induced B16F10 cells. Furthermore, MITF is found to be a key regulatory transcription factor in melanin synthesis; it was down-regulated by LOE through ERK phosphorylation. In this experiment, PD98059 (MEK inhibitor) was used to check whether LOE directly regulated the activity of ERK. Although LOE exerted inhibitory effect on melanin synthesis, we could not observe this effect in PD98059-treated α-MSH induced B16F10. These results strongly indicate that LOE is related to ERK activation and MITF degradation in anti-skin pigmentation. Hence, LOE should be utilized as a whitening agent of skin in the near future.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.4 s.48
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• pp.485-489
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• 2004

Melanin pigmentation in human skin is a major defensive mechanism against ultraviolet light of the sun. Tyrosinase plays a key role in the biosynthesis of melanin. This is why many researches have been focused on regulations in controlling the epidermal melanization. We found that extract of Canavalia lineata inhibits mushroom tyrosinase activity, dopa oxidase activity, and melanin synthesis in B16F10 melanoma cells. To elucidate mRNA level reverse transcription polymerase chain reaction (RT-PCR) technique was used. It was revealed that A subfraction of $CHCI_3$ extract of Canavalia lineara reduced the tyrosinase mRNA expression of B16F10 melanoma cells by reverse transcription polymerase chain reaction (RT-PCR) technique.

• Korean Journal of Acupuncture
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• v.37 no.1
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• pp.24-30
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• 2020

Objectives : The purpose of this study was to investigate melanogenesis inhibition of ethanol extract of Polyporus (EP) by using B16F10 melanoma cells. Methods : We measured antioxidant effect of EP by using 1,1-Diphenyl-1-picrylhydrazyl (DPPH) assay and we confirmed melanin contents and tyrosinase activity of EP in cells. Additionally, the expression of tyrosinase-related protein-1 (TRP-1) and TRP-2 was observed by Western blot. Results : EP showed significantly high radical scavenging activity and inhibition of melanogenesis in dose-dependent manner by decreasing cellular tyrosinase activity and melanin content with or without α-melanin stimulating hormone. TRP-1 and TRP-2 expressions were also suppressed by EP in B16F10 cells. Conclusions : These results suggest that EP inhibits the melanogenesis and it could be a new organic ingredient for hyper-pigmentation.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.271.3-272
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• 2002

This study shows that sphingosine-1-phosphate (SPP) significantly inhibits melanin synthesis in a concentration-dependent manner, and that the activity of tyrosinase was also reduced in SPP-treated cells. In contrast. a specific extracellular signal-regulated protein kinase (ERK) pathway inhibitor, PD98059 increased tyrosinase activity and melanin production, and PD98059 restored the reduced tyrosinase activity and pigmentation induced by SPP. (omitted)

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.763-764
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• 2003

As melanin is a key material for skin pigmentation, inhibitors of melanin formation have been used to cosmetics and drugs to prevent hyperpigmentation. Therefore, search for effective inhibitor$ from various plants were attempted. For this purpose, I examined in vitro tyrosinase assay system. Tyrosinase showed a maximal activity at 4 units concentration of tyrosinase, 10 minutes, 42$^{\circ}C$ and pH 6.5.

• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.192-194
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• 2008

In our previous study, ethylacetate fraction of white ginseng (root of Panax ginseng C.A. Meyer) extract inhibited mushroom tyrosinase activity and melanin production in melanocytes. This study examined its effects on the expression of melanin biosynthesis-related enzymes to explore the depigmenting pathway. Moreover, depigmenting effect on animal skin was examined using UV-B induced hyperpigmented skin of brown guinea pigs. The ethylacetate fraction of the white ginseng extract exhibited depigmenting activity in the skin of brown guinea pig without visible edema. In addition, this fraction reduced tyrosinase expression in melanocytes. The results suggested that ethylacetate fraction of white ginseng extract might be used as skin depigmenting material by inhibition of tyrosinase activity and expression.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.455-462
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• 2000

To investigate how the aqueous extracts of Epimedium koreanum Nakai (EK) affects pigmentation of skin, the aqueous extract of EK at various concentrations were incubated with 1 $\times$ 10$^{5}$ melanoma cells per well for 72 h. The morphology and number of cell line were not changed, but the aqueous extract of EK increased the tyrosinase activity and the content of melanin polymer in the cell line. These results indicate that the aqueous extract of EK promotes melanogenesis of Bl6 mouse melanoma cell line.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.2
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• pp.63-70
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• 1997

It has been observed that local increase in melanin synthesis or uneven distribution can cause local hyperpigmintation or spot. Pigmentary disorders are caused by various factors, including inflammation, imbalance of hormones, and genetic disorder. Recently the harmfulness of Ultraviolet radiation is increasing due to destruction of ozone layer. Excessive exposure to UV radiation caused post-inflammatory pigmentation. Most women want to avoid uneven skin pigmentation. To satisfy this desire many cosmetic companies have been developing melanogenesis inhibitors and finding promising active agents for use in cosmetic preparations for skin whitening. In cosmetic preparations, many inhibitors such as kojic acid, arbutin, ascorbic acid, and licorice extracts6 have been used as whitening purpose. Plant extracts having an inhibitory effect on melanin formation may be a good choice for cosmetic purpose because of their relatively lower side effects. Therefore, we screened 285 plant extracts for their inhibitory activity in tyrosinase. Of the plant extracts, ramulus mori extracts showed potent tyrosinase inhibition activity. We also identified the active compound in the extract.

• The Journal of Korean Medicine
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• v.38 no.4
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• pp.62-81
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• 2017

Objectives: As interests in the beauty of skin is growing continuously, more people are focusing on white and clean skin. Melanin is the major factor that determines skin color. The abnormal concentration of melanin causes various skin diseases such as vitiligo, freckles, and melasma. This study investigated the inhibitory effect of Eriobotryae Folium extracts (EF) with phreatic water (PW) on the melanin synthesis. Methods: The effect of EF on melanin synthesis was evaluated by using mouse melanoma cells (B16F10). To define the mechanisms, real-time PCR and western blot were used. We also evaluated the inhibitory effects of EF and PW on melanin synthesis by using HRM-2 melanin-possessing hairless mice. After UVB irradiation, melanin differences between the skin parts that were treated and untreated with EF and PW. Levels of mRNA were measured by real-time quantitative PCR and histological analysis of the dorsal skin was conducted by hematoxylin and eosin staining. Results: EF inhibited various mechanisms of melanogenesis, and the effect was increased when combined with PW. In vitro experiments have shown that EF inhibited the expressions of tyrosinase related protein-1 (TRP-1) mRNA, tyrosinase mRNA, microphthalmia-associated transcription factor (MITF) mRNA and the tyrosinase inhibitory activation, but it stimulated the extracellular regulated kinase (ERK) mRNA expression. In vivo experiments have shown that EF prevented melanogenesis in the mice dorsal skin and inhibited TRP-1 mRNA expression. Also these effects were increased when combined with PW. Conclusions: EF and PW might be a new and effective treatment for whitening and treating pigmentation of skin.