• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.25-33
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• 2005

Melanocytes synthesize melanin within discrete organelle termed melanosomes which are transferred to the surrounding keratinocytes and can be produced in varying sizes, numbers and densities. Skin whitening products have become increasingly popular in the past few years. The most successful natural skin whitening agents are: arbutin, vitamin C, kojic acid, and mulberry, which are all tyrosinase inhibitors. In this work, melanoston, a melanogenesis inhibitor isolated from yeast was studied to understand its mechanism of melanogenesis inhibition. It was found that melanoston was not a tyrosinase inhibitor, while when melanoston was applied to the B16 melanoma cell culture media, the intracellular tyrosinase activity was decreased by more than $30\%$. When B16 melanoma was stimulated with $\alpha$-MSH, cell morphololgy was dramatically changed to have lots of dendrites on the cell membrane surface. On the other hand, B16 was treated with $\alpha$-MSH and melanoston, simultaneously, the change of cell morphologv was not so great. This inhibitory effect of melanoston was found to be related to the inhibition of intracellar activation and transportation of tyrosinase, which was observed by irmmunostaining of B16 melanoma using anti-tyrosinase antibody. From these results, melanoston was regarded as an inhibitor to the differentiation of melanoma cells.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.184-190
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• 2016

We investigated the antioxidative and protective effects of corn silk (Zea mays L.) ethanol extracts on human HaCaT cells and erythrocytes. The NICS-2 fraction, extracted from corn silk, exhibited favorable 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activities with $IC_{50}$valuesof$13.3{\pm}0.3{\mu}g/mL$ and $14.2{\pm}0.1{\mu}g/mL$ when compared with those of ${\alpha}$-tocopherol, a positive control, with $IC_{50}=10.4{\pm}02.2$ and $22.2{\pm}3.6{\mu}g/mL$, respectively. In addition, we investigated skin protection effects of NICS extracts of corn silk in HaCaT keratinocytes. To investigate the pharmacological potential of NICS-1 and NICS-2 extracts of corn silk on UV-B-induced damage in HaCaT cells, we measured the activity of interleukin (IL) 1a. Our results showed that all the corn silk extracts inhibited the UV-B-induced activity of IL-1a. In particular, NICS-1 extracts of corn silk significantly suppressed IL-1a activity in a dose-dependent manner without inducing cytotoxicity. These results indicate that the ethanol extracts of corn silk (Zea mays L.) could function as natural cytoprotective agents and antioxidants in biological systems, particularly the skin exposed to UV radiation, by protecting cellular membrane against reactive oxygen species (ROS).

• Journal of the Korean Wood Science and Technology
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• v.47 no.2
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• pp.163-177
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• 2019

This study aims to review the relations between the dyeing conditions (i.e., dye concentration, addition amounts of salt and alkali, and dyeing temperature) and dyeing properties and color fastness to light for identifying the optimal dyeing conditions when dyed regenerated woody fibers were obtained through the defibration of waste medium density fiberboard (MDF) using reactive Red H-E3B (Bis-monochlorotriazine (MCT)/MCT type) and reactive Red RB133% (Bis-MCT/Vinyl sulphone type). The dyeing yield (K/S) obtained using two types of reactive dyes increased as the dye concentration increased by 1-10% (on the weight of fiber (OWF)). In addition, the K/S of H-E3B was higher than that of RB133% irrespective of the dye concentration. The color difference of H-E3B after ultraviolet (UV) radiation was lower than that of RB133%, denoting good resistance to discoloration by UV. As the amount of sodium sulfate increased, the color difference and K/S also increased, and the adequate salt content was determined to be 50-70 g/L. Further, the color difference and K/S significantly increased only the addition of 2 g/L of sodium carbonate; however, almost no difference was observed when more than 2 g/L of sodium carbonate was added. The addition amount of sodium carbonate was adequate 5-10 g/L to dyeing the fiber and the pH at this addition level was 10. The dyeing yield of H-E3B increased when the dyeing temperature increased; however, it subsequently decreased after the dyeing temperature became $80^{\circ}C$. The dyeing yield of RB133% was almost the same up to $60-70^{\circ}C$ but declined subsequently. Thus, the adequate temperatures were $80^{\circ}C$ and $60^{\circ}C$ for H-E3B and RB133%, respectively. If the waste MDF woody fiber was dyed under the aforementioned optimal conditions, dyed regenerated woody fiber can be obtained having the following colors: 1.5 to 2.0R with the H-E3B dye and 9.6 to 10.0 PR with RB133%.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.275-279
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• 2015

Micro-algae are unicellular photosynthetic organisms and produce pigments such as chlorophyll and carotenoid. Chlorella contains a lot of protein and functional components like lipids, chlorophyll and carotenoids. In this study we induced mutants of Chlorella vulgaris (C. vulgaris) through ultraviolet radiation (UV-B) and selected two mutants by pigment (chlorophyll and carotenoids) content. We named the mutants ‘UBM1-2’, ‘UBM2-57’ and they were cultivated for 21-days. Cell growth, dry cell weight, protein content, lipid and pigments content were measured. The results indicated that the mutants displayed slower cell growth, lower dry cell weight and protein content than the wild type. However, for UBM1-2 the lipid content was 21% higher than the wild type. In addition, the mutants’ chlorophyll content was 37% and 89% higher than the wild type and the carotenoids content was 27% and 70% higher than the wild type, respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.18 no.1
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• pp.81-98
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• 1992

Hairless mice (Skh:HR-1) exposed to single doses (0.5, 1.0 and 3. OMED) of UV-B radiation were displayed remarkable changes of barrier function and surface morphology. Trans- epidermal water loss (TEWL) as an index of barrier function was measured by evaporimeter, and wrinkle density (WD) as an index of morphological alteration was measured by image analyzer. Significant changes of TEWL were not observed in the control and 0. SMED group, but 1.OMED and 3. OMED groups noted significant difference. TEWL of 3. OMED group was rapidly increased to the 3rd day and decreased until the 14th day when it reached nearly to normal level, Time-courses of TBWL for 1. OMEB and 3. OMED groups displayed similar pattern, but different only in the magnitude. WD were significantly decreased during the 3rd-5th day in all of the irradiated groups and then increased during the last period to the 14th day, but did not recover the normal level at the 14th day. Time-courses of WD for all groups exhibited similarity, and were entirely dependent on the exposed doses. We also observed histological changes which included hyperplasia, sunburn cell (SBC) formation, accumulation of polymorphonuclear leukocyte (PMNs), and loss of collagen of UVB- exposed hairless mouse skin. Changes of TEWL and WD are helpful in understanding of epidermal and dermal damages by single exposure of UVB.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.785-790
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• 2004

Kimchi is well known as a traditional Korean food containing various antioxidative compounds and it has been demonstrated that dietary kimchi inhibit the tissue oxidation and aging in many related studies. Ultraviolet B (UVB) radiation is the most potent among the many related factor to skin photo-aging. This experiment is designed to elucidate the inhibitory effect of solvent fractionation of various kimchi on UVB induced oxidation and erythema formation. Among solvent fractions, phenol content mostly existed in dichloromethane / ethylacetate fraction of buchu kimchi, dichloromethane fraction of Korean cabbage kimchi and ethylacetate / dichloromethane fraction of mustard leaf kimchi. Free radical scavenging activities were higher in dichloromethane and ethylacetate fraction from buchu kimchi, dichloromethane fraction from Korean cabbage kimchi, and ethylacetate fraction from mustard leaf kimchi. When the damage of photo-oxidation by UVB irradiation was tested in the presence of solvent fractions of kimchi, dichloromethane / ethylacetate fraction of buchu kimchi, ethylacetate fraction from Korean cabbage and from mustard leaf kimchi showed the higher protective activities than others. The erythema formations which were induced by UVB irradiation were decreased in solvent fractions of kimchi that hate higher antioxidant activities. In conclusion, kimchi solvent fractions having antioxidant compounds mostly inhibited photo-oxidation and erythema formation by UV-irradiation, therefore kimchi consumption can retard skin aging due to the presence of antioxidative compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.99-106
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• 2005

Skin is continously exposed to ultraviolet (UV) radiation, the major cause of skin disorders including skin aging. Chlorophylls were well known as photosensitizer initiating subsequent chemical reactions such as photooxidative deterioration of cellular structures. This experiment was designed to elucidate the effects of $\beta$-carotene and ascorbic acid with chlorophylls on UVB-induced photooxidation in linoleic acid emulsion model system and skin homogenate of ICR mouse. In linoleic acid emulsion model system, the addition of chlorophyll and $\beta$-carotene accelerated the photooxidation, while high concentration of ascorbic acid prevented. The combination of chlorophylls, $\beta$-carotene and ascorbic acid, which concentrations are simplified from mustard leaf kimchi, prevented UVB-induced photooxidation. Although single treatment of $\beta$-caretene accelerated photooxidaiton, $\beta$-caretene acted as antioxidant in the combination with ascorbic acid. Similarly the addition of individual chlorophylls and $\beta$-carotene accelerated the UVB-induced photooxidation in skin homogenate of ICR mouse. 50 ppm of ascorbic acid did not show the any preventive effect, however 500 ppm of ascorbic acid effectively prevented the oxidation. Photooxidation was prevented in the combination of chlorophylls and $\beta$-carotene with 500 ppm of ascorbic acid and concentration rate of ascorbic acid plays an important role in the prevention of UVB-induced photooxidation.

• Journal of Microbiology and Biotechnology
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• v.29 no.9
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• pp.1349-1360
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• 2019

Chronic exposure to ultraviolet (UV) radiation, regarded as a major cause of extrinsic aging or photoaging characterized by wrinkle formation and skin dehydration, exerts adverse effects on skin by causing the overproduction of reactive oxygen species. Agastache rugosa Kuntze, known as Korean mint, possesses a wide spectrum of biological properties including anti-oxidation, anti-inflammation, and anti-atherosclerosis. Previous studies have reported that A. rugosa protected human keratinocytes against UVB irradiation by restoring the anti-oxidant defense system. However, the anti-photoaging effect of A. rugosa extract (ARE) in animal models has not yet been evaluated. ARE was orally administered to hairless mice at doses of 100 or 250 mg/kg/day along with UVB exposure for 12 weeks. ARE histologically improved UVB-induced wrinkle formation, epidermal thickening, erythema, and hyperpigmentation. In addition, ARE recovered skin moisture by improving skin hydration and transepidermal water loss (TEWL). Along with this, ARE increased hyaluronic acid levels by upregulating HA synthase genes. ARE markedly increased the density of collagen and the amounts of hydroxypoline via two pathways. First, ARE significantly downregulated the mRNA expression of matrix metalloproteinases responsible for collagen degradation by inactivating the mitogen-activated protein kinase/activator protein 1 pathway. Second, ARE stimulated the transforming growth factor beta/Smad signaling, consequently raising the mRNA levels of collagen-related genes. In addition, ARE not only increased the mRNA expression of anti-oxidant enzymes but also decreased inflammatory cytokines by blocking the protein expression of nuclear factor kappa B. Collectively, our findings suggest that A. rugosa may be a potential preventive and therapeutic agent for photoaging.

• Journal of Apiculture
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• v.34 no.2
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• pp.107-115
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• 2019

Bumblebees have apposition compound eyes (one on either side of the head) of about 6,000 ommatidia and three small single-lens ocelli on the frons of their head capsule. The surface of the eye is smooth and interommatidial hairs, as in the honeybee, are not developed. Each ommatidium (approx. 26 ㎛ in diameter) is capped by a hexagonal facet and contains in its centre a 3 ㎛ wide, columnar light-perceiving structure known as the rhabdom. Rhabdoms consist of thousands of regularly aligned, fingerlike microvilli, which in their membranes contain the photopigment molecules. Axons from each ommatidium transmit the information of their photic environment to the visual centres of the brain, where behavioural reactions may be initiated. Since bumblebee eyes possess three classes of spectrally different sensitivity peaks in a ratio of 1:1:6 (UV= 353 nm, blue= 430 nm and green=548 nm) per ommatidium, they use colour vision to find and select flower types that yield pollen and nectar. Ommatidial acceptance angles of at least 3° are used by the bumblebees to discriminate between different flower shapes and sizes, but their ability to detect polarized light appears to be used only for navigational purposes. A flicker fusion frequency of around 110Hz helps the fast flying bumblebee to avoid obstacles. The small ocelli are strongly sensitive to ultraviolet radiation and green wavelengths and appear to act as sensors for light levels akin to a photometer. Unlike the bumblebee's compound eyes, the ocelli would, however, be incapable of forming a useful image.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.407-415
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• 2013

In this study, we investigated the antioxidant activities on HaCaT and the whitening effects on B16F1 melanoma cells of Dendropanax morbifera leaf extract. In an antioxidative activity assay using HaCaT cells, the ethyl acetate ($50{\mu}g/ml$) and aglycone fractions ($25{\mu}g/ml$) of the D. morbifera leaf extract didn't exhibit any characteristics of cytotoxicity. When HaCaT cells were exposed to a single large dose ($800mJ/cm^2$) of UVB, the extracts protected the cells against UVB radiation. When HaCaT cells were treated with 10 mM $H_2O_2$ and $4{\mu}M$ rose bengal, the ethyl acetate ($6.25{\sim}50{\mu}g/ml$) and aglycone ($6.25{\sim}25{\mu}g/ml$) fractions protected the cells against oxidative damage in a concentration dependent manner. When the whitening effects of D. morbifera leaf extract were tested in melanoma B16/F1 cells treated with the a-melanocyte stimulating hormone (${\alpha}$-MSH), the extracts inhibited ${\alpha}$-MSH-stimulated intra/extracellular melanogenesis in a concentration dependent manner. The inhibitory effects of the ethyl acetate and aglycone fractions of D. morbifera leaf extract were 21% and 44% at $25{\mu}g/ml$, respectively. Both are more effective than arbutin (15% at $25{\mu}g/ml$) which is known as a whitening agent. These results indicate that fractions of the D. morbifera leaf can function as cell protectants and natural antioxidants in biological systems, particularly skins exposed to UV radiation by quenching and/or scavenging $^1O_2$ and other ROS, and protecting cells against ROS. In addition, fractions of the D. morbifera leaf can be applied to new whitening cosmetics because of their inhibitory effects on ${\alpha}$-MSH stimulated melanogenesis in B16F1 melanoma cells.