• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5350-5355
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• 2012

Human tyrosinase (hTyr) catalyzes the first and rate limiting step in the biosynthesis of a skin color determinant, melanin. Although a number of cosmetic companies have tried to develop hTyr inhibitors for several decades, absence of 3D structure of hTyr make it impossible to design or screen inhibitors by structure-based approach. Therefore, we built a 3D structure by comparative modeling technique based on the crystal structure of tyrosinase from Bacillus megaterium to provide structural information and to search new hit compounds from database. Our model revealed that two copper atoms of active site located deep inside and were coordinated with six strictly conserved histidine residues coming from four-helix-bundle. Substrate binding site had narrow funnel like shape and its entrance was wide and exposed to solvent. In addition, hTyr-tyrosine and hTyr-kojic acid, a well-known inhibitor, complexes were modeled with the guide of solvent accessible surface generated by in-house software. Our model demonstrated that only phenol group or its analogs could fill the binding site near the nuclear copper center, because inside of binding site had narrow shape relatively. In conclusion, the results of this study may provide helpful information for designing and screening new anti-melanogenic agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.355-362
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• 2013

This study was performed to assess the antioxidant activities and whitening effects of protopectinase enzymes and mechanical maceration from soybeans on melanin synthesis. The whitening effects of enzyme treatment and mechanical maceration were examined by an in vitro mushroom tyrosinase assay and by assessing markers in B16BL6 melanoma cells. We assessed inhibitory effects on the expression of melanogenic enzymes, including tyrosinase, tyrosinase-related protein 1 (TRP-1), and tyrosinase-related protein 2 (TRP-2) in B16BL6 cells. Inhibitory effects on free radical generation were determined by measuring DPPH and hydroxyl radical scavenging activities. In DPPH radical scavenging activity, enzyme treatment and mechanical maceration had a potent anti-oxidant activity in a dose-dependent manner and significantly inhibited tyrosinase activity in vitro and in B16BL6 melanoma cells. There was also an inhibition in the expression of tyrosinase, TRP-1, and TRP-2 in B16BL6 melanoma cells. Our results show that soybean protopectinase treatment inhibits melanogenesis, with the underlying mechanism possibly due to the inhibition of tyrosinase activity and tyrosinase, TRP-1, and TRP-2 expression. We suggest that soybean protopectinase should be contained as natural active ingredients for antioxidant and whitening cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.3 s.52
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• pp.265-271
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• 2005

This study is performed to investigate the effects of citrus essential oils on melanin production in B16 melanoma cells and reactive oxygen species (ROS) generation in RBL 2H3 cells. Five kinds of citrus essential oil (bergamot, grapefruit, lemmon, mandarin, petigrain) did not have any influence on DPPH radical scavenger activity, cell growth and cytotoxicity in B16 melanoma cells. In purified tyrosinase assay, both mandarin and petigrain essential oils dose-dependently inhibited its activity, but bergamot did not. In $1{\mu}M\;{\alpha}-MSH-stimulated$ B16 melanoma cells, all of 5 citrus essential oils inhibited melanin production in $\underline{a}$ dose dependent manner. On the other hand, four kinds of citrus essential oil dose-dependently increased ROS generation in RBL 2H3 mast cells, but mandarin did not. From the above results, it is possible that citrus essential oils nay be developed to be anti-melanogenic agent on the basis of their inhibitory effect on MSH-induced melanin production. Hut we can not rule out the possibility of the induction of allergy and inflammation since citrus essential oils caused ROS generation in RBL 2H3 mast cells.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.1
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• pp.73-78
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• 2009

In order to investigate the potential of a Dayflower (Commelina communis L.) extract as an active in gredient for whitening cosmetics, we prepared aqueous Commelina communis L. extract We measured its mushroom tyrosinase inhibitory activity, cellular tyrosinase activity, and melanin synthesis inhibitory activity in B16 melanoma cells. It did not show inhibitory activity against mushroom tyrosinase but showed melanin synthesis inhibitory activity. In a melanin synthesis inhibition assay using mouse B16-F10 melanoma cell, it suppressed melanin production up to 32% at a concentration of $1,000{\mu}/mL$ without cytotoxicity, and also reduced cellular tyrosinase activity to above 50 % above the concentration of $250{\mu}g/mL$. In study on the melanogenic protein expressions, it had especially influence on expression of tyrosinase protein, which is a well-known key protein on melanogenesis, and tyrosinase expression was gradually decreased in a dose-dependent. Dayflower also blocked N-glycosylation of TRP-2, but affected on the expression of TRP-1 rather than on blocking of N-glycosylation processing. Therefore, this result suggests that aqueous Commelina communis L. extract could be used as an active ingredient for whitening cosmetics.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.94-99
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• 2012

We investigated the in vitro antioxidant and antimelanogenesis effects of ethanol extracts from eggplant (Solanum melongena L.) peels. The total phenolics and chlorogenic acid in ethanol extracts were 2,465 mg/100 g and 2.08 mg/100 g, respectively. ABTS radical scavenging activity, ferric reducing/antioxidant power assay, and malondialdehyde (MDA) inhibitory effect of the extracts increased in a dose-dependent manner. In addition, the extracts generally showed strong UV absorption in the range of UV-B (290-320 nm). The $IC_{50}$ of mushroom tyrosinase inhibitory activity of ethanol extracts from eggplant peels was 870 ${\mu}g/mL$. Importantly, the melanin syntheses of B16/F10 melanoma cells were decreased by extracts in a concentration-dependent manner. Overall, these results suggest that eggplant peels can be potentially applied as a anti-melanogenic agent as well as an antioxidant resource.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1418-1424
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• 2010

This study was performed to assess the antioxidant activities and whitening effects of Sorbus commixta HEDL cortex on melanin synthesis. The whitening effects of Sorbus commixta HEDL cortex water extracts were examined by in vitro mushroom tyrosinase assay and B16BL6 melanoma cells. We assessed inhibitory effects of Sorbus commixta HEDL cortex water extracts on expression of melanogenic enzyme proteins including tyrosinase, tyrosinase-related protein 1 (TRP-1) and tyrosinase-related protein 2 (TRP-2) in B16BL6 cells. Inhibitory effects of Sorbus commixta HEDL cortex onto free radical generation were determined by measuring DPPH and hydroxyl radical scavenging activities. Our results indicated that Sorbus commixta HEDL cortex water extracts effectively inhibited free radical generation. In DPPH radical scavenging activity, Sorbus commixta HEDL cortex water extracts had a potent anti-oxidant activity in a dose-dependent manner. They significantly inhibited tyrosinase activity in vitro and in B16BL6 melanoma cells. Also, Sorbus commixta HEDL cortex suppressed the expression of tyrosinase, TRP-1 and TRP-2 in B16BL6 melanoma cells. These results show that Sorbus commixta HEDL cortex inhibited melanin production on the melanogenesis. The underlying mechanism of Sorbus commixta HEDL cortex on whitening activity may be due to the inhibition of tyrosinase activity and tyrosinase, TRP-1, TRP-2 expression. We suggest that Sorbus commixta HEDL cortex may be contain new natural active ingredients for antioxidant and whitening cosmetics.

• Korean Journal of Medicinal Crop Science
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• v.21 no.5
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• pp.361-371
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• 2013

This study was performed to determine the antimelanogenic effect and tyrosinase inhibitory activities of anthocyanin rich fraction (AN-SLP) from Liriope platyphylla Wang et Tang seeds. Anthocyanins isolated from L. platyphylla seeds revealed the presence of four major anthocyanin components, which were tentatively identified as delphinidin-3-Oglucoside, delphinidin-3-O-rutinoside, petunidin-3-O-rutinoside, and malvidin-3-O-rutinoside using semipreparative HPLC, $^1H$-NMR, $^{13}C$ NMR, FAB-MS and LC/ES-MS. The inhibitory effect of AN-SLP on tyrosinase activity was studied using in vitro (against mushroom tyrosinase) and ex vivo (against B16 melanoma cell tyrosinase) models. Cellular tyrosinase activity was decreased by AN-SLP treatment in B 16 melanoma cells through dose dependent manner, but AN-SLP did not inhibit mushroom tyrosinase and L-DOPA oxidation directly. AN-SLP showed melanin inhibition by 53.2% at 50 ${\mu}g/m{\ell}$ which was 0.7 times more efficient than the antimelanogenic effect of commercial arbutin and kojic acid (36.5%) also did not show cell toxicity. Additionally, AN-SLP inhibited the activity of ${\alpha}$-glucosidase and the glycosylation of tyrosinase in melanoma cell. The resulting unsaturated glycosylation of tyrosinase makes it unstable and disturb correct transportation. From theses results, we conclude that AN-SLP could be used as anti-melanogenic agent for skin whitening.

• Journal of Life Science
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• v.29 no.9
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• pp.972-976
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• 2019

Polyopes affinis is a kind of red algae found in the South coast and near Jeju Island of Korea. The purpose of this study was to investigate the effects of Polyopes affinis ethanol extract (PAEE) on melanogenesis in ${\alpha}-MSH$ stimulated B16F10 melanoma cells. Melanoma cells were cultured for 72 hr treated with PAEE. Total melanin content and the activity of tyrosinase, a key enzyme in melanogenesis, were measured. When the melanin content in B16F10 melanoma cells was tested, PAEE was decreased in a dose-dependent manner: treatment with 100, 300, and $500{\mu}g/ml$ caused 25%, 30%, and 35% reduction, respectively. Treatment of 100, 300, and $500{\mu}g/ml$ of PAEE caused 6%, 12%, and 21% reduction of tyrosinase activities in B16F10 melanoma cells. Also, PAEE suppressed the expression of tyrosinase, tyrosinase-related protein-1, tyrosinase-related protein-2, and melanocyte-inducing transcription factor in B16F10 melanoma cells. A concentration of $500{\mu}g/ml$ of PAEE showed a greater decrease in tyrosinase activity, melanin content, and melanogenic enzyme protein expression. These results indicate that PAEE inhibits melanin synthesis and tyrosinase activity, and Polyopes affinis ethanol extract could be used as a functional whitening agent.

• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.653-659
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• 2020

This study was focused on the synthesis of methoxy polyethylene glycol-oleanolic acid ester (mPEG-OA derivative) and investigation of its water solubility and anti-melanogenic effects. mPEG-OA derivative was identified by 1H and 13C NMR and FT-IR spectroscopic measurements. The water solubilities of mPEG-OA derivative and OA were found to be 13 and 0.013 mg/mL and that of mPEG-OA was found to be 1000-fold higher than that of OA. The effects of mPEG-OA derivative and OA on cell viability were measured using B16F10 melanoma cells. The viability of cells treated with mPEG-OA derivative (250 μM) increased 4-fold compared to that of cells treated with OA (62.5 μM). At mPEG-OA derivative and OA concentrations where the cell viability was unaffected, the inhibitory effect of mPEG-OA derivative and OA on the melanogenesis in B16F10 melanoma cells were 36 and 35% at 50 and 10 μM, respectively. The expression level of microphthalmia-associated transcription (MITF) was also reduced in B16F10 melanoma cells treated with mPEG-OA and OA. Overall, mPEG-OA derivative showed excellent water solubility and inhibitory effects of the melanogenesis, which could be used as a potential formulation for use in whitening functional cosmetic material.

• Korean Journal of Food Science and Technology
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• v.54 no.3
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• pp.280-287
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• 2022

The loquat (Eriobotrya japonica) is a fruit tree belonging to the Rosaceae family. Loquat fruit extracts from three cultivars (Tanaka, Mogi, and Jinwang) were prepared using absolute methanol and homogenization and ultrasound sonication procedures. We measured the total phenolic and flavonoid content of the fruit extracts and their antioxidant capacities. In addition, we evaluated tyrosinase activity and anti-melanogenic effects in B16F1 melanoma cells. The fruit extract from cv. Tanaka had the highest total phenolic content and showed the highest antioxidant capacity in the ABTS assay. The loquat fruit extract from cv. Jinwang had the highest total flavonoid content and showed the highest antioxidant capacity in the DPPH assay. Loquat fruit extracts from the Tanaka and Jinwang cultivars effectively inhibited mushroom tyrosinase activity. The loquat fruit extracts reduced intracellular oxidative stress in B16F1 melanoma cells. Treating B16F1 melanoma cells with loquat fruit extract from cv. Tanaka at a concentration of 125 ㎍/mL effectively inhibited melanin synthesis. However, treating the B16F1 melanoma cells with loquat fruit extracts from the Jinwang and Mogi cultivars did not. These results suggest that loquat fruit extracts from the Tanaka cultivar may serve as potential sources of antioxidants and act as a skin-whitening agent.