• ALGAE
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• v.23 no.3
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• pp.163-175
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• 2008

Phenolic compounds play a major role in the interaction of plants with their environment. They are thought to have been a feature of higher plants since early colonization of the land. Phenolics are crucial for many important aspects of plant life. They can play structural roles in different supporting or protective tissues, for example in cell walls, they can be involved in defence strategies, and signalling properties particularly in the interactions between plants and their environment. In brown algae, phenolic compounds are contained within membrane bound vesicles known as physodes, and their roles in algae are thought to be similar to those of higher plant phenolics. They can be stained using various histochemical stains, however, none of these stains are phenolic specific so care must be taken during interpretation of such results. Many, but not all phenolics are also autofluorescent under UV or violet light. Physodes are involved in cell wall construction, both in primary and secondary walls in brown algae. They bind together with other wall components to make a tough wall. They have also been found to play a role at fertilization, in blocking polyspermy in some species. Sperm are very quickly rendered immobile after phenolic release from newly fertilized zygotes seconds after fertilization. Phenolic compounds are thought to be important herbivore deterrents in some species due to their astringent nature. Phenolic compounds also offer effective UV protection in the early life stages and also the adults of many algal species. In the future, this factor may also make them an important player in the pharmaceutical and skincare industries.

• The Research Journal of the Costume Culture
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• v.12 no.1
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• pp.1-11
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• 2004

This study was carried out on the process of natural dye substances which can flock ultraviolet rays without producing harmful substances by pollution, germs, etc. While making human body safe in contact, extracting Gardenia, Sappan wood, Radix scutellariae, Cromwell, Mugwort, Gallnut, Lac. Those are used for curing diseases, dyeing silk cloth with those extracts, and examining the color fastness, Ultraviolet protection. From this study, the following conclusion was produced. Brightness was lower in pre-mordanting than in post. And color difference showed that Radix scutellariae was the highest. Aluminum-mordanting showed a higher color difference than Fe. Colorfastness to washing was high in all samples, and the degree of color-changing by washing was the highest in the sample dyed by gardenia, pre-mordanted gallnut showed the highest degree. Colorfastness to perspiration was the highest in gardenia. UV-A test showed that all samples a high rate of 85% or higher compared with test white cloth. Especially, post-mordanted radix scutellariae, pre-mordanted gallnut and post-mordanted sappanwood showed a superior blocking rate.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.411-416
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• 2005

The aim of the present work was to prepare the nanosuspension of inorganic pigment which shows light reflection and scattering as efficient sunscreen. The zinc oxide (ZnO) was chosen as an inorganic pigment, and high pressure homogenizer and bead mill have been used for the preparation of nanosuspension. The ZnO nanosuspensions were characterized by particle size, in vitro sun protection factor (SPF) and UV transmittance. ZnO nanosuspension prepared by bead mill showed the average diameter of $119{\pm}4\;nm$, resulting in the high value of SPF $(28.74{\pm}2.06,\;n=20)$, while that prepared by high pressure homogenizer showed the average diameter of $751{\pm}32\;nm$ with the relative lower value of SPF $(21.38{\pm}1.94\;n=20)$. In addition, the film of ZnO nanosuspension prepared by bead mill was showed a high visible ray (VIS) transmittance, indicating a high transparency. In conclusion, a physically stable ZnO nanosuspension in cyclomethicone was successfully prepared using bead mill for the suitable sunscreen preparations.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.4
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• pp.393-401
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• 2016

Ultraviolet (UV) irradiation from the sun is the primary environmental factor that causes skin damages including skin cancer and premature skin aging. Because, even the most powerful sunscreen can't always afford enough protection, it is necessary to enhance the defensive power of skin against UV. Recently, constitutive photomorphogenic protein-1 (COP1) has shown to contribute to the regulation of UVB response of keratinocytes. In this study, we represent that COP1 and its associated protein, de-etiolated 1 (DET1), might participate in photoaging process in human skin as Arabidopsis COP1 does sun-protective function in plants. After UVB irradiation, the decrease of COP1 and DET1 mRNA expression was followed by the increase of c-Jun total protein. Moreover, transfection with DNA vectors expressing COP1 and DET1 down-regulated the c-Jun total protein. We found that Zanthoxylum piperitum extract (ZE) up-regulated the expression of COP1 and DET1 on human keratinocytes, and inhibited the expression of MMP1 which is one of the genes regulated by c-Jun signal. In addition, ZE has been reported to stimulate PPAR-${\alpha}$ and strengthen the skin barrier. We found that ZE decreased the UVB-induced IL-6 and IL-8 in NHEK cells. In human study, ZE protected skin against UV-B induced erythema and erythema-induced pigmentation. These results indicate that ZE could be useful for the protection against the adverse effects of UV irradiation through various mechanisms.

• Safety and Health at Work
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• v.8 no.3
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• pp.237-245
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• 2017

Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.2
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• pp.141-148
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• 2013

The harmful effects of ultraviolet (UV) radiation by increasing sun exposure are making people use sunscreens casually. To keep pace with this trend, many researches about mixing different ingredients or extracting effective ingredients from natural materials are conducted by cosmetics industry. In the present study, we evaluated the UV blocking effect of the sunscreen containing Scutellaria baicalensis Georgi extract. 10 volunteers were measured by minimal erythema dose (MED) and sun protection factor (SPF) of each product. The SPF results were $34.52{\pm}2.13$ and $32.67{\pm}1.44$ in the sunscreen containing Scutellaria baicalensis Georgi extract and that of not containing the substance, respectively. Although the difference of SPF between two products was statistically not significant, it is thought to be meaningful in evaluating clinical effects of the sunscreen using natural substance to humans without any adverse reaction.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2007.11a
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• pp.79-92
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• 2007

Oxidative stress have known to be a risk factor for the degenerative processes and closely related to a lot of diseases. It is well established that antioxidants are good in protection and therapeutic means against oxidative damage. There is increasing interest in natural antioxidants and many natural antioxidants have been found and utilized as the possible protection for various diseases and skin aging. We have screened natural antioxidant agents for cosmeceuticals, nutraceuticals, and drugs as therapeutic and preventive means against oxidative stress, and have developed a number of novel antioxidants from various natural sources. A novel melanin synthesis inhibitor, Melanocin A, isolated from the metabolite of a fungal strain Eupenicillium shearii F80695 inhibited mushroom tyrosinase and melanin biosynthesis of B16 melanoma cells with $IC_{50}$ value of 9.0 nM and MIC value of $0.9\;{\mu}M$, respectively. Melanocin A also exhibited potent antioxidant activity by scavenging of DPPH and superoxide anion radicals. UV was found to increase the level of hydrogen peroxides and other reactive oxygen species (ROS) in skin tissues. This increase in ROS may not only alter the structure and function of many genes and proteins directly but may also modulate their expressions through signal transduction pathways and, ultimately, lead to skin damage. We investigated the effect of Melanocin A on UV-induced premature skin aging. Firstly, the effect of Melanocin A on UV-induced matrix metalloproteinase (MMP)-9 expression in an immortalized human keratinocyte cell line, HaCaT in vitro was investigated. Acute UV irradiation induced MMP-9 expression at both the mRNA and protein levels and Melanocin A suppressed this expression in a dose-dependent manner. We then investigated UV-induced skin changes in hairless mice in vivo by Melanocin A. Chronic exposure of hairless mouse dorsal skin to UV increased skin thickness and induced wrinkle formation and the gelatinase activities of MMP-2 and MMP-9. Moreover, Melanocin A significantly suppressed UV-induced morphologic skin changes and MMP-2 and MMP-9 expression. These results show that Melanocin A can prevent the harmful effects of UV that lead to skin aging. Therefore, we suggest that Melanocin A should be viewed as a potential therapeutic agent for preventing and/or treating premature skin aging. Terrein is a bioactive fungal metabolite isolated from Penicillium species. Terrein has a relatively simple structure and can be easily synthesized. However, the biologic effects of terrein are comparatively unknown. We found for the first time that terrein potently inhibit melanin production in melanocytes and has a strong hypopigmentary effect in a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Treatment of Mel-Ab cells with terrein (10-100 mM) for 4 days significantly reduced melanin levels in a dose-dependent manner. In addition, terrein at the same concentration also reduced tyrosinase activity. We then investigated whether terrein influences the extracellular signal-regulated protein kinase (ERK) pathway and the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. Terrein was found to induce sustained ERK activation and MITF down-regulation, and luciferase assays showed that terrein inhibits MITF promoter activity in a dose-dependent manner. To elucidate the correlation between ERK pathway activation and a decreased MITF transcriptional level, PD98059, a specific inhibitor of the ERK pathway, was applied before terrain treatment and found to abrogate the terrein-induced MITF attenuation. Terrein also reduced the tyrosinase protein level for at least 72 h. These results suggest that terrain reduces melanin synthesis by reducing tyrosinase production via ERK activation, and that this is followed by MITF down-regulation.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.748-758
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• 2014

The purpose of this study is to find the optimum conditions for manufacturing titanium dioxide using a hybrid self-assembly forming method, to confirm the shape, properties and synergy effect of UV protection for hybrid titanium dioxide. Hybrid titanium dioxide, manufactured by forming self-assembly of different sizes consisting of two kinds of titanium dioxides, has micro titanium dioxide (250nm~300nm) for support material, Nano titanium dioxide (20~30nm) for surface material, coating support material. Adjustment experiments of $AlCl_3$ concentration and both titanium dioxide ratio were conducted to find the optimized conditions for the surface coating of titanium dioxide striking a negative charge, a sample made of the optimized process was confirmed through an optical analysis, particle size analysis, and potentiometric analysis. The SPF in-vitro value of the cosmetics samples containing hybrid titanium dioxide showed 15~30% higher levels than the cosmetics samples containing both titanium dioxides mixture.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.598-602
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• 2002

Damage to cells exposed to radiation is primarily attributed to direct effects on the structure of cellular DNA. Radiation-induced damage of pBluescript SK plasmid DNA and Escherichia coli $DH5\alpha$ were examined in the presence of various branched oligosaccharides, polysaccharides, and/or 8-MOP (8-methoxypsoralen). Branched oligosaccharides efficiently protected DNA and cells exposed to ultrasoft X-ray and UV irradiation. In the presence of 0.2% (w/v) branched oligosaccharides and polysaccharides, DNA can be protected from damage due to W and ultrasoft X-ray by a factor of 1.3-2.1 fo1d and 3.2-8.3 fold, respectively. The protective effect of cells exposed to UV or ultrasoft X-ray was also observed by branched oligosaccharides. The combination of MOP, a photoreagent, with carbohydrates increased the protective effects for DNA and cells, compared with that of a single use of MOP or carbohydrate alone.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.2
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• pp.159-167
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• 2023

Titanium dioxide (TiO₂) is commonly used in sunscreen formulations to protect the skin surface and prevent the penetration of harmful ultraviolet (UV) rays by the physical scattering action of light. However, a disadvantage of using TiO₂ is that it can cause white turbidity when used on skin due to its inactive mineral ingredient. In addition, when TiO₂ particles are reduced to nanosize to eliminate opacity, they can increase the transmittance of visible light and reduce whitening, but may lead to serious skin problems, such as allergic inflammation. To overcome these issues, the bandgap of TiO₂ was controlled by adjusting the amount of oxygen defect and nitrogen amount, resulting in color TiO₂ tailored to the skin. This innovative technology can reduce the whitening phenomenon and effectively block blue light, which is known to cause skin aging by inducing active oxygen. The bandgap controlled TiO₂ compounds proposed in this study are hypoallergenic, broad-spectrum, and environmentally friendly. Furthermore, these compounds have been shown to significantly enhance sun protection factor (SPF) of sunscreens, demonstrating their compatibility with blue light blocking products.