• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2121-2132
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• 2018

Abnormal melanin synthesis results in several hyperpigmentary disorders such as freckles, melanoderma, age spots, and other related conditions. In this study, we investigated the anti-melanogenic effects of an extract from the microalgae Chlamydomonas reinhardtii (CE) and potential mechanisms responsible for its inhibitory effect in B16F10, normal human epidermal melanocyte cells, and human skin-equivalent models. The CE extract showed significant dose-dependent inhibitory effects on ${\alpha}$-melanocyte-stimulating, hormone-induced melanin synthesis in cells. Additionally, the CE extract exhibited suppressive effects on the mRNA and protein expression of microphthalmia-associated transcription factor, tyrosinase, tyrosinase-related protein-1, and tyrosinase-related protein-2. The CE extract also inhibited the phosphorylation of protein kinase A and extracellular signal-related kinase, which function as upstream regulators of melanogenesis. Using a three-dimensional, reconstructed pigmented epidermis model, the CE-mediated, anti-pigmentation effects were confirmed by Fontana-Masson staining and melanin content assays. Taken together, CE extract can be used as an anti-pigmentation agent.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.187-196
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• 2003

The cytokines are the hormone-like proteins, which are produced in the mononuclear cells. They have many roles, such as immune mediators, cell differentiations, angiogenesis. The chemokines have chemotactic effects which control the host immune response. There were few reports about the cytokines associated with musculoskeletal tumors. From late 1980s, the cytokine studies of bone tumors such as osteosarcoma were started, but most studies for benign and malignant musculoskeletal tumors were left to be explored. To evaluate the characteristics of the cytokines in variable musculoskeletal tumors, tissues were obtained from the seven patients who visited the Yeungnam University hospital from February to July 2000. They were lipoma (1 case), parosteal osteoma (1 case), enchondroma (2 cases), pigmented villonodular synovitis (1 case), ganglion (1 case), and metastaic squamous cell carcinoma (1 case). The gene experession of the cytokines were analyzed by RNase protection assay (RPA) and reverse transcription-polymerase chain reaction (RT-PCR). The lipoma and parosteal osteoma expressed MIP-$1{\beta}$, and IP-10 genes. The two enchondromas showed different results, one expressed all of MIP-$1{\alpha}$, MIP-$1{\beta}$ and IP-10 genes but the other expressed none of above. The pigmented villonodular synovitis strongly expressed MIP-$1{\alpha}$ and IP-10 when compared with the other cases. The ganglion did not express all of the chemokines mentioned above. And the metastatic squamous cell carcinoma expressed all of the chemokines and especially IP-10 was highly expressed. Even though this study has only a few cases, these results provide a basis for the cytokine mediating network study in musculoskeletal tumors.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.3
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• pp.249-254
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• 2014

The purpose of this study is to characterize the effects of KHG26792 (3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride), a potential skin whitening agent, on melanin synthesis and identify the underlying mechanism of action. Our data showed that KHG26792 significantly reduced melanin synthesis in a dose-dependent manner. Additionally, KHG26792 downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase, the rate-limiting enzyme in melanogenesis, although tyrosinase was not inhibited directly. KHG26792 activated extracellular signal-regulated kinase (ERK), whereas an ERK pathway inhibitor, PD98059, rescued KHG26792-induced hypopigmentation. These results suggest that KHG26792 decreases melanin production via ERK activation. Moreover, the hypopigmentary effects of KHG26792 were confirmed in a pigmented skin equivalent model using Cervi cornus Colla (deer antler glue), in which the color of the pigmented artificial skin became lighter after treatment with KHG26792. In summary, our findings suggest that KHG26792 is a novel skin whitening agent.

• ALGAE
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• v.30 no.1
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• pp.35-47
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• 2015

The marine sand-dwelling dinoflagellate Polykrikos lebourae possesses obvious gold-brown pigmented plastids as well as taeniocyst-nematocyst complex structures. Despite of the presence of the visible plastids, previous attempts to establish this species in culture all failed and thus the unavailability of cultures of this species has posed a major obstacle to further detailed exploration of ecophysiology of the dinoflagellate. Here, we isolated P. lebourae from sandy sediment of an intertidal flat on Korean western coast, successfully established it in culture, and have been maintaining the stock culture over the past 3 years. Using this stock culture, we explored phagotrophy and potential prey resources of P. lebourae, growth and grazing responses of P. lebourae to different prey organisms, the effect of prey concentration on growth and grazing rates and gross growth efficiency (GGE) of P. lebourae when fed three different prey organisms, and the growth kinetics of P. lebourae under different light regimes. P. lebourae captured prey cells using a tow filament and then phagocytized them through the posterior end. The dinoflagellate was capable of ingesting a broad range of prey species varying in size, but not all prey species tested in this study supported its sustained growth. GGE of P. lebourae was extremely high at low prey concentration and moderate or low at high prey concentrations, indicating that P. lebourae grows heterotrophically at high prey concentrations but its growth seems to be more dependent on a certain growth factor or photosynthesis of plastids derived from the prey. In the presence of prey in excess, P. lebourae grew well at moderate light intensity of $40{\mu}mol$ photons $m^{-2}s^{-1}$, but did not grow at dim and high (10 or $120{\mu}mol$ photons $m^{-2}s^{-1}$) light intensities. Our results suggest that the benthic dinoflagellate P. lebourae is an obligate mixotroph, requiring both prey and light for sustained growth and survival.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.357-369
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• 2001

In this present study, the healing process and the recurrence of pigmentation were evaluated clinically and histologically in accordance with the extent and the range of pigmentation after phenol was applied to remove melanin pigmentation in gingiva. Six mongrel dogs were used. The melanin pigmentation in canine gingiva were classified into slight, moderate and severe according to the extent of pigmentation and divided into local and diffuse types according to the range. Following general and local anesthesia, 90% phenol was applied to the pigmented gingiva of the subjects with small cotton balls until the surface was etched to be whitish and was neutralized with small cotton balls soaked by 95% alcohol. The contralateral pigmented gingiva to the one treated with phenol, was treated by surgical deepithelialization. At 1, 3 and 8 weeks, the treated gingiva was examined clinically and evaluated histologically following H-E stain, and HMB 45 stain for melanocyte after biopsy. In the phenol treated sites, epithelium and connective tissue healed normally and there was no pigmentation at 1 week. At 3 weeks of healing, melanin repigmentation was observed in the severe local type and moderate to severe diffuse type. In the surgically deepithelialized sites, healing was delayed, compared to phenol treated sites and the infiltration of the inflammatory cells and congestion in connective tissue was shown at 1 week. At 3 weeks, healing was completed and there was a partial melanin repigmentation. At 8 weeks of healing, the extent and the range of repigmentation were increased in both group according to the extent or range priot to depigmentation procedure. These results suggpriorest that the removal of melanin pigmentation with 90% phenol application result in normal healing process of gingiva. However, in the severe local type and moderate to severe diffuse type, sites treated with phenol showed repigmentation at 3 week, which was earlier than surgical deepithelialized sites. Therefore it is required to select appropriate method according to initial condition of pigmentation.

• Journal of Ginseng Research
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• v.45 no.1
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• pp.98-107
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• 2021

Background: Ginseng extracts and ginseng-fermented products are widely used as functional cosmetic ingredients for their whitening and antiwrinkle effects. Recently, increasing attention has been given to bioactive metabolites isolated from endophytic fungi. However, little is known about the bioactive metabolites of the fungi associated with Panax ginseng Meyer. Methods: An endophytic fungus, Penicillium sp. SNF123 was isolated from the root of P. ginseng, from which acremonidin E was purified. Acremonidin E was tested on melanin synthesis in the murine melanoma cell line B16F10, in the human melanoma cell line MNT-1, and in a pigmented 3D-human skin model, Melanoderm. Results: Acremonidin E reduced melanogenesis in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16F10 cells with minimal cytotoxicity. qRT-PCR analysis demonstrated that acremonidin E downregulated melanogenic genes, including tyrosinase and tyrosinase-related protein 1 (TRP-1), while their enzymatic activities were unaffected. The antimelanogenic effects of acremonidin E were further confirmed in MNT-1 and a pigmented 3D human epidermal skin model, Melanoderm. Immunohistological examination of the Melanoderm further confirmed the regression of both melanin synthesis and melanocyte activation in the treated tissue. Conclusion: This study demonstrates that acremonidin E, a bioactive metabolite derived from a fungal endophyte of P. ginseng, can inhibit melanin synthesis by downregulating tyrosinase, illuminating the potential utility of microorganisms associated with P. ginseng for cosmetic ingredients.

• Journal of fish pathology
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• v.28 no.3
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• pp.145-155
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• 2015

The pathogenecity of atypical Aeromonas salmonicida was studied in healthy Oreochromis niloticus. Inoculum at concentration of $1.5{\times}10^8CFU/ml$ and $3{\times}10^8CFU/ml$ was injected into healthy fish through intramuscular and intraperitoneal injections. Experimentally infected Oreochromis niloticus showed ulceration at the dorsal musculature and trunk region in addition to black coloration, congested gills, exophthalmia, and ocular hemorrhage. Congested liver and kidney were recorded in post-mortem examination. Mortality of the experimentally infected Oreochromis niloticus reached 100% after intramuscular injection at concentration of $3{\times}10^8CFU/ml$. Histopathological investigation of infected organs was also performed. There was a focal area of bundles of skeletal musculature showing hyalinization. In addition, hyperplasia, congestion, and fusion were noticed in the gill lamellae. There was also congestion in the blood vessels in the ocular chamber. Severe congestion was also noticed in the central vein of liver associated with focal aggregation of the melanin pigmented cells in the parenchyma. Degenerative changes were noticed in the epithelial cells lining of kidney tubules. Plant extracts carvacrol and its biological precursor cymene were found to be effective in treating experimentally infected Oreochromis niloticus at concentration of 100 or 200 ppm.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.230-234
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• 2011

While preparing a floristic study of Korean hepatics, we discovered the 4 unrecorded species Alobiellopsis parvifolius, Calypogeia japonica, Hattoria yakushimensis and Nardia subclavata. A. parvifolius is often confused with Solenostoma fusiforme (Steph.) Amak. in appearance, but the former differs by occasional presence of underleaves and a large hyaline outer cells of stem. C. japonica is similar to C. tosana (Steph.) Steph. The former, however, is separated from the latter by 2-3 biconcentric oil-bodies per cell compared to 3-5 grape oil-bodies per cell. H. yakushimensis is a monotypic genus based on a Japanese species. This genus is characterized by unlobed, closely imbricate leaves with margins distinctly incurved and usually pigmented with a reddish purple color. N. subclavata is similar to N. assamica (Mitt.) Amakawa in large underleaves and globular oil-bodies. The former, however, is separated from the latter by convex trigones versus concave trigones, smooth cuticles versus smooth to verrucose cuticles, and oil-bodies occurring in each cell versus occurring in approximately half or fewer leaf cells.

• ALGAE
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• v.22 no.1
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• pp.31-36
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• 2007

The gametophytic filaments of two genetically distinct taxa of Bangia from New Zealand showed unusual rhizoidal development in comparative culture experiments. In the past Bangia has been reported to possess simple, colourless rhizoids that extend from the basal cells of the unbranched filaments, whereas in this study the rhizoids observed became pigmented and multicellular. A reversal of growth direction occurred and filamentous extensions developed from the rhizoids under some culture conditions. These extensions were either prostrate or resembled new gametophytic filaments. This is the first report for filamentous members of the Bangiales of the development of such stolon-like rhizoids, apparently serving as a form of vegetative reproduction.

• The Journal of Natural Sciences
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• v.19 no.1
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• pp.27-35
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• 2008

The importance of microbial activity in the alteration and deterioration of stone and concrete walls has been frequently neglected. Organisms present on stone monuments can include photolithoautotrophs, such as algae, cyanobacteria, mosses, and higher plants. Because of their ability to survive repeated drying and rehydration cycles and high UV levels, the cyanobacteria are particularly important on exposed surfaces. The cyanobactria distributed on the surface of the stone cultural heritages in Gwanschoksa, Nonsan city were investigated. Chlorococcus sp. Aanabaena sp. Gloeocapsa sp Lyngbya sp. Stigomena sp. Synechocystis sp were identified. Haplaosiphon fontinalis and Stigonema turfaceum, which were not recoded is Korea, were also identified. Cells often have thick pigmented sheath in dry, sun-exposed environment and shorter filament, which can be different than that in aquatic systems. Special attention should be paid to production of an adequate DNA database in order to accelerate the rate at which information on the species present in biofilms become available.