• 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.

• Journal of Life Science
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• v.31 no.2
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• pp.192-198
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• 2021

Red yeast rice has been extensively used as food and traditional medicine for thousands of years in East Asian countries. It is produced by the fermentation of a particular yeast (in general, Monascus purpureus) as rice and various cereals (barley, soybean, etc.). Monascus sp. produces many secondary metabolites during its growth, including pigments, monacolins, and γ-aminobutyric acid. Some metabolites―specifically, monacolin K, γ-aminobutyric acid, dimerumic acid, and monascus pigments―have been reported to lower cholesterol and blood pressure while showing anti-obesity effects. In this study, we investigated the anti-obesity effect of ethanol extract from red yeast barley (RYB) fermented with Monascus sp. BHN-MK 2 on 3T3-L1 cells. The anti-obesity effects of RYB extract were examined: its lipid accumulation inhibitory effect was tested by Oil Red O staining, and obesity-related mRNA expression levels were tested by real-time RT-PCR in MDI stimulated 3T3-L1 cells. The intracellular lipid content of MDI-stimulated 3T3-L1 cells decreased significantly to 5.04%, 12.24%, and 23.52% in response to 200, 400, and 800 ㎍/ml RYB, respectively. Moreovers, we evaluated that RYB extract significantly downregulated the expression of C/EBPα, SREBP-1, and PPAR-γ gene in a dose-dependent manner. As a result, red yeast barley ethanol extracts exerted the strongest anti-obesity effects. Also, the results indicate that red yeast barley could be used as a functional anti-obesity food material.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.8-18
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• 2005

We studied seasonal distribution of the microphytobenthos and their primary production with $C^{14}$ method and carried out pigment analysis with HPLC in an estuarine mudflat of the Ganghwa Island, Korea from May 2002 to April 2004. The abundances of microphytobenthos were higher at the middle than upper part and lower part of intertidal flat. Abundances of microphytobenthos ranged from $2.3{\times}10^5\;cells\;cm^{-2}$ to $140.9{\times}10^5\;cells cm^{-2}$. The bloom of microphytobenthos was observed in the early spring and then it decreased from spring to summer and autumn. The pennate diatom was a predominated group among the microphytobenthos in this area. The dominant species were Paralia sulcata, Cylindrotheca closterium and Nitzschia sp.. Nitzschia sp. and Cylindrotheca closterium were predominant in February. The results of pigment analysis suggest the presence of diatoms, euglenophytes, chlorophytes, cyanobacteria, cryptophytes, chrysophytes, prymnesiophytes, dinoflagellates and prasinophytes. The biomass of microphytobenthos ranged from 1.18 to 34.25 mg chl-a $m^{-2}$, with a mean of 7.60 mg chl-a $m^{-2}$. The mean ratio of Fuco/Chl a was 0.7 which indicates that most of biomasses of microphytobenthos were due to diatoms. The ratios of Chl b/Chl a ranged from 0 to 0.82(with a mean of 0.17), implying that euglenophytes and chlorophytes lived together in special period seasonally. Temporal variation of primary production ranged from 4.2 to 113.0 $mgC{\cdot}m^{-2}{\cdot}hr^{-1}$(mean value was 33.9 $mgC{\cdot}m^{-2}{\cdot}hr^{-1}$ and initial slope$({\alpha})$ was measured from 0.002-0.005$(mgC\;mgchl-a^{-1}\;hr^{-1}){\cdot}({\mu}E\;m^{-2}\;s^{-1})^{-1}$. Assimilation number$(P_m)$ was in the range of 0.50-1.32 $mgC{\cdot}mgChl-a{\cdot}hr^{-1}$ and daily primary production ranged from 20.9 to 678.1 $mgC{\cdot}m^{-2}{\cdot}d^{-1}$(mean value was 206.72 $mgC{\cdot}m^{-2}{\cdot}^{-1}$).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.257-261
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• 2000

Integumentary system of the polychaete, Perinezeis aibuhitensis was consisted cuticular, epidermal and dermal layers. Excretory pores opened in cuticular layer, which is covered with epicuticular projections. The hemidesmosomes were observed between supporting cell and basal area of cuticular layer. The epidermal layer was consisted supporting cells and unicellular glands. Supporting cell was relatively larger than the other neighbouring cells, and the nucleus had one to two nucleolus. Cytoplasm of the supporting cell had well-developed intracellular organs such as tonofilaments, mitochondria, rough endoplasmic reticula, free ribosomes and pigment granules of electron dense. The gland cells were reacted with blue in AB-PAS, and classified into the three types such as ${\alpha},\;{\beta}\;and\;{\gamma}$ from the transmission electron microscopic observation. Type ${\alpha}$ gland cell was ovoid and the cytoplasm had well-developed tonofilaments and membrane bounded secretory granules of $0.8{\~}1.5 {\mu}m$ in diameter. Type ${\beta}$ gland cell had a large vacuole and secretory granules of $0.5{\~}0.8 {\mu}m$, which scattered evenly in the cytoplasm. Type ${\gamma}$ gland cell had well-developed endoplasmic reticulum, Golgi auparatus and secretory granules of $0.2{\~}0.3 {\mu}m$ in diameter. The electron density of this granules was the highest among the granules.

• Journal of Life Science
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• v.32 no.5
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• pp.331-339
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• 2022

Melanin is a pigment produced by melanocytes to protect the skin from external stimuli, mainly ultraviolet (UV) rays. However, abnormal and excessive production of melanin causes hyperpigmentation disorders, such as freckles, age spots, and discoloration. Natural cosmeceuticals are a new trend for treating or preventing hyperpigmentation due to fewer side effects and biocompatibility. In this context, the current study focused on Cnidium japonicum, a halophyte with several uses in folk medicine, to evaluate its potential as a skin-whitening agent. The effect of C. japonicum extract (CJE) on melanin production was analyzed in melanogenesis-stimulated B16F10 melanoma cells. The results showed that CJE successfully inhibited the oxidation of tyrosine and L-DOPA by tyrosinase and subsequently decreased the production of the key enzymes responsible for melanin production: tyrosinase, tyrosinase-related protein-1, and protein-2. This effect was confirmed by decreased intracellular and extracellular melanin levels in B16F10 melanoma cells after CJE treatment. Further experiments to elucidate the action mechanism revealed that CJE treatment suppressed melanin production by inhibiting the activation of glycogen synthase kinase 3 β (GSKβ)/β-catenin and protein kinase A (PKA)/cAMP-response element binding protein (CREB) pathways, which are the upstream activators of melanogenesis. In conclusion, the present study suggests that C. japonicum is a potential natural source of bioactive substances for the development of novel cosmeceuticals that can act against hyperpigmentation.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.303-314
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• 2021

To understand how to efficiently observe the biomass and community of phytoplankton, phytoplankton sampling was carried out from June to October 2019 at the Yeongju dam sediment control reservoir(YJ) and Bohyeonsan dam reservoir(BH1 and BH2). The results derived from microscopic observation, such as the conventional phytoplankton qualitative/quantitative analysis, and from the CHEMTAX method based on the pigments, were compared. The relative contribution of phytoplankton, calculated by the microscopy and CHEMTAX methods, showed a significant difference in all four classes: cryptophyta, chlorophyta, cyanobacteria, and diatoms. In addition, the correlation between the two observation methods was poor. This might be caused by methodological differences in microscopy that do not consider the varying cell sizes among phytoplankton species. In this study, by converting the cells into carbon, the slope between both carbon biomasses based on microscopy and CHEMTAX was improved close to the 1 : 1 line, and the y-intercept was closer to 0 for cryptophyta and diatoms. For cyanobacteria, the slope increased, the y-intercept decreased, and the plot approached 1 : 1 although the correlation coefficients were not improved in all classes. The present study suggests that application of CHEMTAX based on pigment analysis could be a possible approach to efficiently determine the relative carbon proportions of individual classes of phytoplankton community composition.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.4
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• pp.313-321
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• 2023

Platycodon grandiflorus (P. grandiflorus) flower is a perennial plant belonging to the family Campanulaceae and has many excellent pharmacological effects, so it has been used as a medicinal ingredient since ancient times. In addition, anthocyanin is a purple or blue natural pigment contained in plant flowers and fruits, and is known as a powerful antioxidant. The purpose of this study was to confirm the dermatological functionality of P. grandiflorus flower extract and the value of the bluish anthocyanin contained in flowers as a cosmetic material as a natural pigment. Firstly, 50% ethanol and 80% ethanol were added to the P. grandiflorus flower and extracted under reflux for 4 h at 25, 60, and 80 ℃, and the pH of each treatment group was similar. Based on the anthocyanin content and chromaticity (E^*ab), 50% ethanol 60 ℃ extraction conditions showing the color development most similar to the natural color of the P. grandifloras flower were selected, and a sample was prepared by concentrating and lyophilizing. The analysis results showed that the total phenol, total flavonoid, and total anthocyanin contents were in the ranges of 23 ㎍/mL, 16 ㎍/mL, and 0.17 ㎍/mL, respectively. The P. grandiflorus flower extract suppressed the production of nitric oxide (NO) and interleukin-6 (IL-6) in lipopolysaccharide (LPS) induced RAW264.7 cells. Furthermore, the P. grandiflorus flower extract showed wound healing effects through the promotion of skin cell migration in TNF-α stimulated human keratinocytes. The stability of anthocyanin and extract color was studied during a storage period of 50 days at various temperatures (4 ℃, 25 ℃, and 45 ℃). Color values (L, a, and b) of the P. grandiflorus flower extract changed over 50 days, whereas the bluish-purple color of the extract was stabilized using 5% maltodextrin. These results suggest that P. grandiflorus flower extract may be useful as a natural cosmetic pigment.

• Journal of fish pathology
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• v.18 no.1
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• pp.39-48
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• 2005

Pathogenicity of Vibrio tapetis, the causative bacterium of 'brown ring disease (BRD)' was evaluated in Manila clams (Ruditapes philippinarumi by artificially 0.1 $m\ell$ infection of $1.0\times10^5$cells and $1.0\times10^8$ cells at 20 $^{\circ}C$. A PCR assay based on 16S rRNA to detect the bacteria in clam tissues was established. Accumulative mortality of clams infected with $1.0\times10^7$cells and $1.0\times10^4$ cells per an individual of the bacteria was 67.5% and 7.5%, respectively. However, the deposit of brown pigment in the inner shells by accumulation of chonchiolin was not found. The bacteria were not be able to re-isolate from the infected clams by the conventional agar plate method but were easily detected by PCR assay established in this experiment. In clams artificially infected with 10 species of Vibrio, a 414bp for V. tapetis was detected in PCR assay. The specific band in the clams infected with $1.0\times10^4$cells per an individual of V. tapetis was detected only in gills one day after the infection but never be found in any tissues including gills three days after the infection. In the case of clams infected with $1.0\times10^8$cells per an individual of V. tapetis the specific band was detected in gills and intestine one day after the infection, in all tissues three days after the infection, and then in gills and adductor muscle nine days after the infection. The PCR assay was applied to detect V. tapetis in manila clam, surf clam (Mactra veneriformis), oyster (Crassostrea gigas) and Thomas' rapa whelk (Rapana venosa) taken from Taean and Gochang from April to July 2004. The infection rates were detected to 23.1% and 9.4% in the oyster and surf clam, while manila clam and Thomas' rapa whelk were not found.

• Korean Journal of Ichthyology
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• v.6 no.2
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• pp.237-243
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• 1994

This work was conducted to study sex differentiation in the black sea bream, Acanthopagrus schlegeli (Bleeker), using a histological method for the appearance of primordial germ cell, formation of primitive gonads, differentiation of female and male from newly hatched larva to the ovotestis stage of fish. The 3~4 primordial germ cells of $6.8{\sim}7.2\;{\mu}m$ in size, which were buried under fibrous mesenchymal tissue between gut duct and notochord of pre-larva with a total length (T.L.) of 2.4 mm at 3 days after hatching. The proto-gonial cells were located in the epithelium of the coelom attached with pigment cells of juvenile with 6.4 mm in T.L. at 21 days after hatching. In juvenile of 20.8 mm in T.L. at 59 days after hatching, the proto-gonial cells were migrated to the retro-peritoneum through the lineshaped primitive gonad composed of fibrous mesenchymal tissue. In juvenile of 7.8 em in T.L. at 186 days after hatching, the mitotic division of proto-gonial cell appeared in the lineshaped primitive gonad having many eosinophilic granule cells and abundant fibrous connective tissue. In juvenile of 9.5 em in T.L. at 254 days after hatching, the gonad was occupied by abundant fibrous connective tissue, bundles of spermatocyte and spermatid. In juvenile of 10.5 cm in T.L. at 13 months after hatching, the gonad was divided into cortical layer and medullary layer. The former was composed of bundles of a few spermatocytes and proto-gonial cells, the latter was filled with the fibrous mesenchymal tissue and a few proto-gonial cells. In juvenile of 14.7 em in T.L. at 16 months after hatching, the gonad was separated into ovarian part and testicular part by the fibrous connective tissue. The ovarian part is consisted of ovarian cavity and oocytes of perinucleolus stage. The testicular part was occupied by spermatogonia in the cyst.