• 대한화장품학회지
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• 제23권3호
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• pp.115-121
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• 1997

To identify inhibitors of melanogenesis, we compared the effects of 5 compounds on mushroom tyrosinase, human melanocytic tyrosinase activity and melanin content. The cytotoxicyty of the components were also tested on cultured human melanoctes. Kojic acid showed marked inhibitory effect both on mushroom and human tyrosinase activity. This action of kijic acid is stronger than that of ascorbic acid. Arbutin inhibited human tyrosinase activity of cultured melanocytes although it had slightly inhibitory effect on mushroom tyrosinase activity. Azelaic acid had no effect on human tyrosinase activity. Melanin production was inhibited significantly by kojic acid and tranexamic acid. MTT assay showed that all of the compounds were non-cytotoxic to melanocytes at the concentrations tested. These results suggest that the effect of kojic acid on cultured meanocytes involve inhibition of tyrosinase activity and melanogenesis without affection the cell number.

• 약학회지
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• 제45권5호
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• pp.522-528
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• 2001

Tyrosinase plays an important role in the process of melanin biosynthesis, and it is a biochemical target enzyme for skin-whitening agents and the remedy for disturbances in pigmentation. We have screened 25 natural plant extracts for inhibitory effects against DOPA oxidase activity of tyrosinase. For the inhibitory effect against DOPA oxidase activity of tyrosinase, the recombinant human tyrosinase and the purified mushroom tyrosinase were used. Each of the dried plants extracted with methanol, and then the extracts were subjected to sequential fractionations with methylene chloride, ethyl acetate, n-butanol and water, respective The methylene chloride fractions of Angelica tenuissima, Nardostachys chinensis, Bombyx mop and Saposhnikovia divaricata, and the n-butanol fraction of Bombyx mori notably inhibited the human tyrosinase activity as well as mushroom tyrosinase activity (more than 90% inhibition). This study suggests that the above extracts have a potential as whitening agents as single ingredients or in combination with other of the extracts.

• Journal of Applied Biological Chemistry
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• 제58권4호
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• pp.333-338
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• 2015

본 연구에서는 단삼 열수 추출물의 human epidermal melanocye (HEM) 세포에서의 미백활성을 측정하였다. 버섯유래의 tyrosinase 저해능 측정결과 $1,000{\mu}g/mL$의 농도에서 42%의 저해율을 나타내었으며, HEM 세포내의 tyrosinase, 멜라닌 생합성 저해능은 $5{\mu}g/mL$에서 26, 25%의 저해능을 나타내었다. 단삼 추출물의 미백과 관련된 tyrosinase, tyrosinase related protein 1 (TRP-1), tyrosinase related protein 2 (TRP-2), microphthalmia associated transcription factor (MITF)의 단백질 및 유전자 양이 감소함을 나타내었다. 또한 그 상위 단계인 cAMP 발현이 $5{\mu}g/mL$ 농도에서 41% 감소하는 것을 확인하였다. 본 실험을 통하여 단삼 추출물이 cAMP를 효과적으로 억제함으로써, 이를 통해 tyrosinase 활성뿐만 아니라 TRP-1, TRP-2 그리고 MITF 발현을 효과적으로 저해 한다는 사실을 확인하여 기능성 미백 화장품 소재로서의 활용 가능성을 제시하고자 한다.

• 대한본초학회지
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• 제30권6호
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• pp.1-6
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• 2015

Objectives : Draconis Resina (DR), the resin of Daemonorops draco Bl., is used to circulate the blood and to stop bleeding. It also has been used to generate flesh including ulceration. The present study investigated the effects of DR extract on collagen metabolism in human fibroblasts and tyrosinase activity in mushroom tyrosinase.Methods : The effect of DR extract on type I procollagen production (collagen type I synthesis) and collagenase (matrix metalloproteinase-1, henceforth referred as MMP-1) activity in human normal fibroblasts cell line. Hs68 cells after ultraviolet B (UVB, 312 nm) irradiation was measured using the enzyme - linked immunosorbent assay (ELISA). The tyrosinase activity was also measured to find out the whitening effects in mushroom tyrosinase by ELISA method.Results : There was no cytotoxicity at DR extract at concentrations of 10 μg/ml, 30 μg/ml, and 100 μg/ml. DR extract significantly inhibited the increase of collagenase activity, whereas it did not show on the reduction of type I procollagen in UVB damaged Hs68 cells. DR extract did not reduce the L - DOPA oxidation. However, it significantly reduced the tyrosinase activity by DR extract at concentraions of 0.1 mg/ml, 1 mg/ml and 10 mg/ml.Conclusions : In conclusion, DR showed the anti-wrinkle and whitening effects via the inhibition of collagenase production and the tyrosinase activity. These results suggest that DR may have potential as an anti-aging ingredient in cosmetic herb markets.

• 동의생리병리학회지
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• 제25권3호
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• pp.528-532
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• 2011

This study was designed to investigate the collagen metabolism and tyrosinase activity of Meretrix extracts (ME). The effect of ME on type I procollagen production and collagenase activity in human normal fibroblasts HS68 after UVB (312 nm) irradiation was measured by ELISA method. The tyrosinase activity after treatment of ME was measured as well. Type I procollagen production was recovered by ME in UVB damaged HS68 cells. The increased collagenase activity after UVB damage was significantly recovered by ME. The tyrosinase activity and L-DOPA oxidation were significantly reduced as well. However, the effects on tyrosinase activity and L-DOPA oxidation were not powerful enough to be used as whitening agents. ME showed the anti-wrinkle effects and some whitening effects in vitro. These results suggest that ME may be a useful drug as an anti-wrinkle treatments.

• 한국산업보건학회지
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• 제19권3호
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• pp.261-269
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• 2009

To evaluate the effect of antioxidant on the cytotoxicity induced by oxidative stress of reactive oxygen species (ROS) in cultured human skin melanocytes, colorimeric assay of XTT and tyrosinase activity assay were adopted after human skin melanocytes were preincubated for 2 hours in the media containing various concentrations of superoxide dismutase (SOD) before the treatment of hydrogen peroxide. Light microscopic study was carried out in same cultures. The results of this study were as follows 1. Cell viability of human skin melanocytes was significantly decreased by 30 and $40{\mu}M$ of hydrogen peroxide($H_2O_2$), respectively. 2. XTT50 was determined at $30{\mu}M$ after human skin melanocytes were treated with $10{\sim}40{\mu}M$ of hydrogen peroxide for 6 hours. 3. The cell viability of cultured human skin melanocytes pretreated with SOD was increased than that of cultured human skin melanocytes treated with $H_2O_2$ dose-dependently. 4. In tyrosinase activity of human skin melanocytes, the cell treated with SOD showed brown stain compared with $H_2O_2$ treated cells, dark stain. 5. In light microscopy, cultured human skin melanocytes exposed to $H_2O_2$ showed morphological changes such as the decreased cell number and cytoplasmic processes, compared with control. 6. In light microscopy, cultured human skin melanocytes pretreated with SOD showed the increase of cell number and cytoplasmic processes compared with $H_2O_2-treated$ group. From these results, it is suggested that oxidative stress of ROS such as $H_2O_2$ has cytotoxicity by showing the decreased cell viability, the increased tyrosinase activity and mophological changes of the decreased cell number and cytoplasmic processes. While, antioxidant like SOD was effective in the prevention of oxidative stress-mediated cytotoxicity by the increased cell viability, decreased tyrosinase activity and the protection of degenerative morphological changes in cultured human skin melanocytes.

• 한국자원식물학회지
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• 제14권1호
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• pp.32-37
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• 2001

한약재 174종으로부터 tyrosinase 저해제를 탐색하였다. 한약재는 30일간 methanol에 담가 놓은 후, 그 추출액을 제조하여 사용하였다 Tyrosinase의 활성을 측정하기 위해서는 효소 mushroom Tyrosinase와 기질 L-DOPA, phosphate buffer를 사용하였다. 탐색 결과, 한약재 174종 중 14개종이 tyrosinase를 저해 효과를 보였고, 그중 오배자 추출액이 inhibition activity가 가장 높게 나타났다.

• Archives of Pharmacal Research
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• 제26권10호
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• pp.840-845
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• 2003

Temperature change is one of the major environmental factors that influence the human skin. However, the relationship between temperature and melanogenesis has received little attention. In the present study, we investigated the effects of temperature change on melanogenesis in a mouse melanocyte cell line (Mel-Ab), and primary cultured human melanocytes. We found that Mel-Ab cells cultured at low temperatures (31 and 34$^{\circ}C$) produce less melanin than cells at 37$^{\circ}C$. These results were confirmed by experiments upon human melanocytes, demonstrating that the hypopigmenting effect of low temperatures is not cell type dependent. The observed melanin production was found to be accompanied by tyrosinase activity at each temperature, indicating that tyrosinase activity is regulated by temperature. We further examined whether the incubation period at low temperatures plays an important role in the regulation of melanogenesis. Short exposures to 27$^{\circ}C$ for 1 h or 3 h did not affect tyrosinase activity or melanin synthesis, whereas long exposures to 31$^{\circ}C$ for 2 days or 6 days significantly reduced tyrosinase activity and melanin synthesis in a duration-dependent manner. Our results suggest that exposure to low temperature and the duration of this exposure are important regulators of melanogenesis.

• 한국축산식품학회지
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• 제32권5호
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• pp.678-684
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• 2012

본 연구는 tyrosinase 활성 저해효과가 있는 젖산균인 L plantarum M23 균주를 이용하여 멜라닌 형성을 억제하기 위한 최적 발효유 제조조건을 설정하는데 그 목적이 있다. 3수준 4인자 중심합성 계획법을 통해 실험설계하여 반응표면분석법을 사용하였다. 독립변수로는 yeast extract 농도(%, $X_1$), 포도첨가량(%, $X_2$), 배양온도($^{\circ}C$, $X_3$), 배양시간(h, $X_4$)을 설정하였고, 종속변수로는 pH(pH, $Y_1$), 종합적 기호도(score, $Y_2$)와 tyrosinase inhibitory activity(%, $Y_3$)를 설정하였으며, tyrosinase inhibitory activity가 가장 높고 pH는 4.4를 동시에 만족하는 최적화를 실시한 결과 yeast extract 농도는 0.13%, 포도 첨가량은 2.95%, 배양 온도는 $37.1^{\circ}C$, 배양 시간은 14.8 h일 때 예상되는 pH는 4.42, 기호도는 7.06, tyrosinase inhibitory activity은 86.65%이었으며, 실제 실험 결과 pH는 4.35, 기호도는 6.86, tyrosinase inhibitory activity은 84.05%로서 큰 차이를 나타내지 않았다. 이러한 결과를 토대로 melanin 생합성과정의 key enzyme인 tyrosinase을 활성억제하는 L. plantarum M23을 이용한 발효유는 피부의 미백 작용과 노화 억제 작용에 기여할 것으로 사료되었다.

• Biomolecules & Therapeutics
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• 제26권3호
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• pp.282-289
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• 2018

Melanin is a pigment produced from tyrosine in melanocytes. Although melanin has a protective role against UVB radiation-induced damage, it is also associated with the development of melanoma and darker skin tone. Tyrosinase is a key enzyme in melanin synthesis, which regulates the rate-limiting step during conversion of tyrosine into DOPA and dopaquinone. To develop effective RNA interference therapeutics, we designed a melanin siRNA pool by applying multiple prediction programs to reduce human tyrosinase levels. First, 272 siRNAs passed the target accessibility evaluation using the RNAxs program. Then we selected 34 siRNA sequences with ${\Delta}G{\geq}-34.6kcal/mol$, i-Score value ${\geq}65$, and siRNA scales score ${\leq}30$. siRNAs were designed as 19-bp RNA duplexes with an asymmetric 3' overhang at the 3' end of the antisense strand. We tested if these siRNAs effectively reduced tyrosinase gene expression using qRT-PCR and found that 17 siRNA sequences were more effective than commercially available siRNA. Three siRNAs further tested showed an effective visual color change in MNT-1 human cells without cytotoxic effects, indicating these sequences are anti-melanogenic. Our study revealed that human tyrosinase siRNAs could be efficiently designed using multiple prediction algorithms.