• 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.

• Biomolecules & Therapeutics
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• v.32 no.2
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• pp.249-260
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• 2024

New supplements with preventive effects against skin photodamage are receiving increasing attention. This study evaluated the anti-photoaging effects of salmon nasal cartilage proteoglycan (SPG), acting as a functional material for skin health. We administered SPG to in vitro and in vivo models exposed to ultraviolet B (UVB) radiation and assessed its moisturizing and anti-wrinkle effects on dorsal mouse skin and keratinocytes and dermal fibroblasts cell lines. These results showed that SPG restored the levels of filaggrin, involucrin, and AQP3 in the epidermis of UVB-irradiated dorsal skin and keratinocytes, thereby enhancing the keratinization process and water flow. Additionally, SPG treatment increased the levels of hyaluronan and skin ceramide, the major components of intercellular lipids in the epidermis. Furthermore, SPG treatment significantly increased the levels of collagen and procollagen type 1 by down-regulating matrix metalloproteinase 1, which play a crucial role in skin fibroblasts, in both in vitro and in vivo models. In addition, SPG strongly inhibited mitogen-activated protein kinase (MAPKs) signaling, the including extracellular signal-regulated kinase, c-Jun N-terminal kinase (JNK), and p38. These findings suggest that dietary SPG may be an attractive functional food for preventing UVB-induced photoaging. And this SPG product may provide its best benefit when treating several signs of skin photoaging.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.3
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• pp.263-273
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• 2012

Recent studies have uncovered attractive properties of para-coumaric acid (PCA) as a potential skin hywhitening agent. The purpose of the current study was to examine its UVB-shielding effects. Effects of PCA on the viability of HaCaT cells exposed to UVB were assessed in vitro in comparison with other aromatic amino acid metabolites that have similar UV absorption spectra. For in vivo test, PCA cream (1.5 %) and cream base were topically applied to the dorsal skin of SKH-1 hairless mice and the inflammatory responses due to UVB exposure were monitored by changes in skin color (erythema) and thickness (edema). The cream application-UVB exposure regimen was repeated every other day for a total of 12 sessions. When HaCaT cells were irradiated with UVB, there was a dose-dependent decline in cell viability. The cell viability decline due to UVB exposure (10 mJ $cm^{-2}$) was significantly prevented by 100 ${\mu}M$ PCA, cinnamic acid, urocanic acid, or indole acrylic acid by 39, 27, 39, or 31 %, respectively. Topical application of PCA cream onto the dorsal skin of hairless mice (10 ${\mu}g\;cm^{-2}$) attenuated the changes of color parameters, $L^*$, $a^*$, $b^*$ values, and thickness of the UVB (150 mJ $cm^{-2}$)-exposed skin by 59, 50, 58, and 53 %, respectively. The current study, together with the previous studies that demonstrated the antimelanogenic effects of PCA, suggested that PCA may prevent not only dyspigmentation but also inflammatory reactions in the UVB-exposed skin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.3
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• pp.255-261
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• 2012

The skin is continuously exposed to environmental stresses. One of the most important stress factor is UV radiation. UV radiation causes a variety of biological effects on the skin, including inflammation, pigmentation, photoaging and cancer. Therefore in this study, we tried to search for skin-protective antioxidant materials from marine natural products (Porphyra Thalli, Laminariae japonicae thallus, Ostreae Concha, Sargassum Thallus, Undaria thallus, Haliotidis Concha, Agar, Codium thalli, Hizikia fusiforme thalli; HFE, Thalli) which exhibit protective activities against UVB-induced cytotoxicity and oxidative cell death and antiaging effects. As a results, UVB-induced cytotoxicity and cell death were effectively suppressed by treatment of Sargassum Thallus, Agar, Haliotidis Concha, Codium thalli, Thalli ethanol extracts. UVB-induced cell death was mediated by intracellular accumulation or ROS, which was significantly inhibited by treatment with marine natural products extracts. Also, The protective effect of these marine natural products seemed to be mediated by increased expression of type I collagen and Type I procollagen. These results suggest that marine natural products may have anti-aging effects new functional materials against oxidative stress-mediated skin damages.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.4
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• pp.271-280
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• 2010

Ultraviolet radiation (UV) is a major cause of photodamages to human skin and the immediate responses of the skin to UV include the erythema and edema. In an attempt to find effective UV-protecting agents to be used in cosmetics, a number of plant extracts were screened in the cell-based assays. Among the total of 38 plant extracts tested, 3 plant extracts derived from Sasa quelpaertensis, Althaea rosea, and Dryopteris crassirhizoma attenuated the UVB-induced cytotoxicity as well as melanin synthesis in cultured human epidermal melanocytes. The anti-inflammatory effects of these plant extracts were further examined in animal models. A control or test cream containing 1% of a plant extract was topically applied to ears of a C57BL/6 mouse or the dorsal skin of a SKH-1 hafirless mouse before and after the exposure to UVB. The change in ear thickness or dorsal skin redness due to UVB exposure was determined to monitor edema and erythema, respectively. All three test creams exhibited anti-inflammatory effects in both experiments. The creams containing Sasa quelpaertensis, Althaea rosea or Dryopteris crassirhizoma extract alleviated the UVB-induced edema response on day 4 by 53.8 %, 56.4 % and 31.1 %, respectively. They also inhibited the erythema formation on day 2 by 45.7 %, 34.1 % and 20.5 %, respectively. This study suggests that the selected plant extracts formulated in cosmetics may attenuate skin inflammation caused by overexposure to UV.

• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.235-241
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• 2003

The effect of ultraviolet (UV) radiation on the characteristics of algae-derived dissolved organic matter (DOM) was examined by comparing the biodegradability and DOM fraction distribution of algal DOM before and after UV exposure. Algal DOM from two axenic cultures of Microcystis aeruginosa and Oscillatoria agardhii were irradiated for 24 h at a UV intensity of 42 W/$m^2$. A complete degradation of algal DOM during the UV exposure did not occur, remaining at constant concentrations of dissolved organic carbon(DOC). After UV exposure, however, microbial degradations were reduced by 17% in M. aeruginosa and 53% in O. agardhii, respectively, and decomposition rates also were two times lower in UV exposed algal DOM. In addition, the chemical compositions of algal DOM altered substantially after UV radiation exposure. The proportions of hydrophilic bases (HiB; protein-like DOM) decreased considerably in both algal DOM sources after UV exposure (16.8% and 20.0% of DOM, respectively), whereas those of hydrophilic acids (HiA; carboxylic acids-like DOM) increased as much as the decrease of the HiB fraction. Capillary ion electrophoresis (CE) analysis showed that several carboxylic acids increased significantly after UV exposure, further confirming an increase in HiA fractions. The results of this study clearly indicate that algal DOM can be changed in its chemical composition as well as biodegradability without complete degradation by UV radiation.

• 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%.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.1
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• pp.15-31
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• 2012

In our previous studies, the antioxidant, anti-aging, and antibacterial activities of Persicaria hydropipier L. extract, and the moisturizing effect of cream containing P. hydropipier extract were investigated. In this study, the cellular protective effects of P. hydropipier extract and isoquercitrin, main component from P. hydropipier in $^1O_2$-induced photohemolysis of human erythrocytes and ultraviolet B (UVB)-exposed HaCaT cells were investigated. Liposomes such as ethosome and elastic liposome for enhanced transdermal delivery were prepared. Size, loading efficiency, stability, and cumulative permeated amounts of ethosomes and elastic liposomes were evaluated. P. hydropipier extract and isoquercitrin showed more prominent cellular protective effect than (+)-${\alpha}$-tocopherol, known as lipid antioxidant at $5{\mu}g/mL$. P. hydropipier extract didn't show any characteristics of cytotoxicity at $50{\mu}g/mL$. When HaCaT cells were exposed to a single large dose ($400mJ/cm^2$) of UVB, the extract protected the cells against UVB radiation in a concentration dependent manner ($12.5{\sim}50{\mu}g/mL$). Cell viability of HaCaT cells exposed to UVB $400mJ/cm^2$ was increased by treatment with P. hydropipier extract or isoquercitrin from 36 % (cell viability of positve control groups) to 90 % (cell viability of P. hydropipier extract or isoquercitrin- treated groups). The size of 0.04 % P. hydropiper extract loaded ethosomes was 173.0 nm and the loading efficiency was 55.58 %. 0.04 % P. hydropiper extract loaded ethosomes were stable with as monodisperse particles for 1 week. The ethosome exhibited more skin permeability than general liposome and ethanol solution. The optimal ratio of lipid to surfactant ($Tego^{(R)}$ care 450) of 0.1 % P. hydropiper extract loaded elastic liposomes was observed to be 95 : 5. Vesicle size of 0.1 % P. hydropiper extract loaded elastic liposome was 176.5 nm. The deformability index of the elastic liposome was 16.4. The loading efficiency was 68.8 %. The elastic liposome containing P. hydropiper extract showed more skin permeability than liposome without surfactant ($Tego^{(R)}$ care 450).

• 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.

• Korean Journal of Plant Resources
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• v.29 no.2
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• pp.155-162
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• 2016

Melanin is produced by melanocytes of the melanoepidermic unit and other cell types. These cells secrete and distribute the melanin pigment, which provides protection from ultraviolet radiation. In this study, the inhibitory activity against tyrosinase and melanin biosynthesis in B16F10 melanoma cells and anti-wrinkling effects on human dermal fibroblasts of Dendrobium speciosum ethanol extract were investigated. The Dendrobium speciosum extract inhibited melanin biosynthesis and tyrosinase activity in a dose-dependent manner in comparison with an untreated control group. Treatment with the Dendrobium speciosum extract suppressed α-MSH-stimulated melanogenesis in B16F10 cells and the dendrite outgrowth of melanocyte/melanoma cells. The α-MSH-induced mRNA expression of tyrosinase-related protein-1 (TRP-1), tyrosinase-related protein-2 (TRP-2) and microphthalmia-associated transcription factor (MITF) was significantly attenuated in a concentration-dependent manner by Dendrobium speciosum treatment. In addition, Dendrobium speciosum treatment increased production of type I procollagen synthesis in human dermal fibroblasts. Dendrobium speciosum ethanol extract exhibited a potent inhibitory effect on melanin biosynthesis, tyrosinase activity and increased procollagen synthesis. These results indicate that Dendrobium speciosum shows promise as an ingredient in cosmeceutical products due to its whitening and anti-wrinkle effects.