• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.81-96
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• 2018

In this study, physicochemical properties of the natural jadeite powder were investigated and also the wash-off pack and liquid foundation containing the jadeite powder were prepared. In addition, each of these formulations was evaluated by various functional effects, sensory evaluation, stability and skin safety. In the wash-off pack, the far-infrared ray emissivity and radiation energy values increased as a function of the jadeite powder content. At a 3% jadeite powder content, the skin temperature increased by about $0.5^{\circ}C$ when the jadeite powder-containing formulation was applied to the skin. Besides, the chroma of the liquid foundation containing the jadeite powder more clearly expressed the original color of the skin. Moisture content measurements of the wash-off pack and liquid foundation containing the jadeite powder showed the highest moisture uptake of 5.0% and 63.0%, respectively. In sensorial test, the wash-off pack formulations containing the jadeite powder demonstrated improved affinities toward a skin, adherency, and moistness and combatted itching. The liquid foundation containing jadeite powder showed also improved affinities except for the coverage when compared to control formulations. Furthermore, the stability evaluation for 8 weeks revealed neither discoloration nor separation phenomenon for the formulations containing the jadeite powder. Moreover, the pH was found to be stable up to 8 weeks and the viscosity up to 4 weeks. Skin safety assessments showed that all formulations containing the jadeite powder were non-irritating. These results suggest that the jadeite powder as an inorganic pigment may serve as a new multi-functional cosmetic ingredient with stability and safety.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.4
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• pp.349-355
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• 2017

Skin tone plays a key role in one of the determinant for facial attractiveness. Most female customers have an interest in choosing skin color and improving their skin tone and their needs have been contributed the expansion of cosmetic products in the market. Recently, cosmetic customers, who want bright skin, are also interested in healthy and lively-looking skin. However, there is no method to evaluate the skin tone with the complexion-describing adjectives (CDAs). Therefore, this study was conducted to find the ways to objectify and digitize the CDA. We obtained that quasi $L^*$ at dark skin is 65 and quasi $L^*$ at bright skin is 74 for standard images, which are selected from our data base. To match the following seven CDAs: pale, clear, radiant, lively, healthy, rosy and dull, the colors of both images were adjusted by 30 panels. The quasi $L^*$, $a^*$ and $b^*$ were converted from the RGB values of the manipulated images. The differences between the quasi $L^*$, $a^*$ and $b^*$ values of standard images and manipulated images reflecting each CDA were statistically significant (p < 0.05). However, there were no statistical significances between the $L^*$ values of dark and bright skin images that were modified in accordance with each CDA and there also were no statistical significances between the quasi $a^*$ values of dark and bright skin for pale and clear CDAs. From the statistical analysis, the CDAs were observed to form three groups: (i) pale-clear-radiant, (ii) lively-healthy-rosy and (iii) dull. We recognized that people have a similar opinion about perception of CDAs. Following our results of this study, we establish new standard method for sensibility evaluation which is difficult to carry out scientifically or objectively.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.43-49
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• 2012

In this study, we investigated the antibacterial activity and stability of a cream containing Hippophae rhamnoides leaf extract. The MIC values of ethyl acetate fraction from an H. rhamnoides leaf on Escherichia coli, Pityrosporum ovale, Propionibacterium acnes and Staphylococcus aureus were 0.5%, 0.25%, 0.25% and 0.06%, respectively. Stability evaluations, pH, viscosity and absorbance of the cream containing 0.25% ethyl acetate fraction of H. rhamnoides, were performed. The cream was measured under 4 different temperature conditions under sunlight at 2-week intervals for 12 weeks. The viscosity and pH were measured by a comparison of the experimental cream with a similar control cream. The H. rhamnoides extract was found to have contributed to the stability of the emulsion product via a protective effect in maintaining the viscosity of the cream against sunlight. The absorbance variations of the experimental cream at 270 nm were, under sunlight; $45^{\circ}C$, $37^{\circ}C$, $25^{\circ}C$, and $4^{\circ}C$. In addition, any change in color or smell was not observed through the 12 weeks of the experimental period. These results indicated that the cream containing 0.25% ethyl acetate fraction of H. rhamnoides leaf extract was stable. Accordingly, this suggests that further study is needed to provide additional information for manufacturers, who are seeking the application of the extract to improve anti-oxidant and antibacterial activities and the stability of cosmetic products.