• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.475-478
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• 2009

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.2051-2053
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• 2010

• Bulletin of the Korean Chemical Society
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• 제29권8호
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• pp.1569-1571
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• 2008

• 대한화장품학회지
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• 제43권3호
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• pp.265-271
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• 2017

본 연구에서는 홍차 흑효모 발효물의 기능성화장품 소재로서의 가능성을 규명하고자 항산화, 미백, 항주름 효능을 확인하였다. 홍차 흑효모 발효물의 결과는 홍차 추출물, 흑효모 발효물과 비교하여 나타내었다. 항산화능 평가 결과 홍차 흑효모 발효물은 흑효모 발효물보다 뛰어난 DPPH 라디칼 소거능을 나타냈으며 홍차 추출물과는 유사한 결과를 나타냈다. 과산화수소로 유도된 세포 내 활성산소종 실험에서도 홍차 흑효모 발효물은 유의적 제거 활성을 보였다. 또한 홍차 흑효모 발효물은 tyrosinase 저해 활성을 보이며 Melan-a, B16F10 세포를 이용한 멜라닌 형성이 억제됨을 확인하였다. 항주름 효능 확인을 위해 콜라겐 분해 효소(MMP-1)를 측정한 결과 홍차 흑효모 발효물이 홍차 추출물, 흑효모 발효물보다 높은 항주름 활성을 보였다. 본 연구 결과를 통해 홍차 흑효모 발효물은 항산화능 효능을 보이며 미백, 항주름 효능을 보아 기능성 화장품 소재로 개발될 수 있음을 확인하였다.

• Biomolecules & Therapeutics
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• 제22권5호
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• pp.431-437
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• 2014

Synthetic compounds that are used in the clinic to regulate skin hyperpigmentation, such as arbutin, hydroquinone, and kojic acid, are only moderately effective. But, their use is limited by side effects. As part of an effort to overcome the limitations, we developed resveratrol-enriched rice (RR) using genetic engineering technique. Each of resveratrol and rice has been reported to produce anti-melanogenic effects. Therefore, we hypothesized that RR would show more anti-melanogenic effects than those of resveratrol or rice alone. Anti-melanogenic effect of RR was done by using melan-a mouse melanocytes. The depigmenting efficacy was then observed following topical application of the RR to UVB-stimulated hyperpigmented dorsal skin of guinea pigs. Treatment with RR extract resulted a $21.4{\pm}0.7%$ decrease in tyrosinase expression at melan-a cells. Colorimetric analysis showed a significantly lower depigmenting value by day 9 following treatment with RR in UVB-irradiated guinea pigs the dorsal skin (p<0.01), indicating that RR produced a depigmentation effect. By staining with Fontana-Masson stain, we found that the RR-treated group had more effect histopathologically in epidermal melanin production than resveratrol or rice alone-treated group. RR was associated with reduction in the levels of microphthalmia-associated transcription factor (MITF), and downregulation of tyrosinase and tyrosinase-related protein (TRP-2) expression, leading to inhibit epidermal melanin production by western blot analysis. This study suggests that the resveratrol-enriched rice may be a promising candidate in regulating skin pigmentation with UVB exposure.

• 대한화장품학회지
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• 제28권1호
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• pp.135-149
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• 2002

To date, research on the regulation of melanogenesis has focused on factors which affect tyrosinase, the rate-limiting enzyme in the melanogenic pathway, by searching for chemicals which competitively inhibit tyrosinase function. Many types of tyrosinase inhibitors have been developed, but no satisfactory results have been made clinically until now, To find a new whitening agent, which effectively inhibits melanogenesis, we synthesized several compounds and selected compounds by cell-based assay system. Finally, 3, 4, 5-trimethoxy cinnamaie thymol ester(TCTE, Melasolv) was selected and the effects of TCTE on melanogenesis were investigated. Treatment of mouse-derived melanocyte melan-a cells with TCTE results in a marked down-regulation of tyrosinase activity. 80% decrease of tyrosinase activity occurs with 30uM TCTE treatment for 72 hours without affecting cell growth. The inhibition of tyrosinase activity is dose-dependent and melanin content was also decreased to 40%. From the in vitro tyrosinase assay using cell extract, TCTE does not act as a direct inhibitor of the enzyme. Treatment of melan-a cultures with TCTE blocks the increase in tyrosinase activity by either forskolin, 3-isobutyl-1-methtyl-xanthine. TCTE decreased the expression of tyrosinase, TRP-1 without effects on TRP-2 protein expression through the down regulation of tyrosinase and TRP-1 mRNA. From the results of cAMP immunoassays, intracellular levels of the cyclin nucleotide are unaffected in cells treated with TCTE. The inhibitory effects of melanin synthesis were also shown in reconstitute human epidermis model by topical application. These findings suggest that TCTE can be used for studying the regulation of melanogenesis and depigmenting agent.

• Interaction and multiscale mechanics
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• 제2권2호
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• pp.177-187
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• 2009

Machine or structural members subjected to fatigue loading will have a crack initiated during early part of their life. Therefore analysis of members with cracks and other discontinuities is very important. Finite element method has enjoyed widespread use in engineering, but it is not convenient for crack problems as the region very close to crack tip is to be discretized with very fine mesh. However, as the body force method (BFM), requires only the boundary of the discontinuity (crack or hole) to be discretized it is easy versatile technique to analyze such problems. In the present work fundamental solution for concentrated load x + iy acting in the semi-infinite plate at an arbitrary point $z_0=x_0+iy_0$ is considered. These fundamental solutions are in complex form ${\phi}(z)$ and ${\psi}(z)$ (England 1971). These potentials are known as Melan potentials (Ramakrishna 1994). A crack in the semi-infinite plate as shown in Fig. 1 is considered. This crack is divided into number of divisions. By applying pair of body forces on a division, the resultant forces on the remaining 'N'divisions are to be found for which ${\phi}_1(z)$ and ${\psi}_1(z)$ are derived. Body force method is applied to calculate stress intensity factor for crack in semi-infinite plate. Also for the case of crack emanating from circular hole in semi-infinite plate radial stress, hoop stress and shear stress are calculated around the hole and crack. Convergent results are obtained by body force method. These results are compared with FEM results.

• 대한화장품학회지
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• 제31권1호
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• pp.17-23
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• 2005

본 연구자들은 백출의 메탄올 추출물로부터 분리, 정제한 selina-4(14), 7(11)-dien-8-one (Selina)이 B16 멜라노마 세포에 대하여 매우 강력한 미백효과가 있음을 밝혀내었다. 본 연구에서는 Selina의 non-tumorigenic melanocyte cell line인 Melan-a 세포에 대한 작용 메카니즘에 대한 보고를 하고자 한다. 덧붙여 Selina를 함유하고 있는 제품의 임상효과도 연구하였다. Selina는 $10 {\mu}g/mL$의 농도에서 세포독성을 보이지 않으면서 Melan-a 세포의 멜라닌 합성을 $50\%$ 저해하였다. 또한 $10 {\mu}g/mL$의 Selina의 처리에 의하여 타이로시네이즈의 활성이 $60\%$ 감소시키지만 타이로시네이즈에 대한 직접적인 저해활성은 없는 것으로 밝혀졌다. 이러한 Selina의 작용 기작을 밝히기 위하여 연구자들은 타이로시네이즈, TRP-1, TRP-2의 3가지 유전자의 mRNA 수준과 단백질의 발현량을 RT-PCR과 western blotting을 이용하여 연구하였다. 그 결과 $10 {\mu}g/mL$의 Selina 처리에 의하여 타이로시네이즈의 mRNA와 단백질 양은 현저히 감소하였지만 TRP-1과 TRP-2의 mRNA 및 단백질 양에는 변화가 없었다. 이러한 결과는 Selina가 그 미백효과를 주로 타이로시네이즈의 발현조절에 의하여 나타낸다는 것을 알 수 있다. $0.2\%$의 Selina를 함유하는 화장품 제형을 이용, 7주간 20명의 피시험자를 대상으로 한 임상시험에서도 어떠한 부작용도 없이 통계적으로 유의한(p<0.05) 수준의 미백효과를 볼 수 있었다. 이상의 결과를 종합해 볼 때 Selina는 깨끗하고 밝은 피부를 위한 유용하면서도 안전한 신규 미백 원료임을 알 수 있다.

• Preventive Nutrition and Food Science
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• 제21권2호
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• pp.155-159
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• 2016

Previous research showed that resveratrol (trans-3,4',5-trihydroxystilbene) and pinostilbene (trans-3-methoxy-4',5-dihydroxystilbene) were able to inhibit tyrosinase directly; however, anti-melanogenic effects of pterostilbene (trans-3,5-dimethoxy-4'-hydroxystilbene) and resveratrol trimethyl ether (RTE) have not been compared. To investigate the hypopigmentation effects of pterostilbene and RTE, melanin contents and intracellular tyrosinase activity were determined by western blot analysis. Firstly, pterostilbene showed the inhibitory effects on ${\alpha}$-melanocyte stimulating hormone (MSH)-induced melanin synthesis stronger than RTE, resveratrol, and arbutin. Pterostilbene inhibited melanin biosynthesis in a dose-dependent manner in ${\alpha}$-MSH-stimulated B16/F10 murine melanoma cells. Specifically, melanin content and intracellular tyrosinase activity were inhibited by 63% and 58%, respectively, in response to treatment with $10{\mu}m$ of pterostilbene. The results of western blot analysis indicated that pterostilbene induced downregulation of tyrosinase protein expression and suppression of ${\alpha}$-MSH-stimulated melan-A protein expression stronger than RTE or resveratrol. Based on these results, our study suggests that pterostilbene can induce hypopigmentation effects more effectively than resveratrol and RTE, and it functions via downregulation of protein expression associated with hyperpigmentation in ${\alpha}$-MSH-triggered B16/F10 murine melanoma cells.

• Journal of Ginseng Research
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• 제30권2호
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• pp.82-87
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• 2006

백삼과 홍삼의 quercetin, cinnamic acid, p-coumaric acid, maltol, esculetin 함량을 측정한 결과 백삼에는 cinnamic acid가 가장 높은 함량을 보였고, 홍삼에는 증숙과정 중에 생성되는특이 성분인 maltol이 가장 높은 함량을 나타냈다. 인삼시료 중 백삼의 ethyl acetate 분획물은 melan-a 세포주에서의 세포생존율 대비 멜라닌 생성억제활성측정, UV-흡수도 측정, tyrosinase 억제활성 측정에서 모두 우수한 활성을 나타내었으며, 이의 활성 성분으로는 cinnamic acid가 주요한 역할을 하는 것으로 판단되어진다. 한편, maltol을 다량 함유한 홍삼 ethyl acetate 분획물은 UV-흡수 활성을 보였으나 다른 유의적인 활성을 나타내지 않았다. 따라서 인삼소재 중 백삼 ethyl acetate 분획물은 피부미백소재로써의 기능을 가지는 것으로 판단된다.