• Korean Journal of Pharmacognosy
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• v.45 no.3
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• pp.209-213
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• 2014

The anti-melanogenic substance was isolated from the root of Angelica gigas Nakai by silica gel column chromatography, preparative HPLC and TLC. As a result of the structure analysis by mass, $^1H$-NMR, and $^{13}C$-NMR spectrometry, the compound was identified as demethylsuberosin. Demethylsuberosin reduced melanin contents of B16F1 melanoma cells in a dose-dependent manner and decreased to about 74% at a concentration $5{\mu}g/ml$. Demethylsuberosin inhibited the expression in microphthalmia associated transcription factor (MITF), tyrosinase, tyrosinase related protein-1 (TRP-1), and tyrosinase related protein-2 (TRP-2) in melanocytes. These results suggest that the whitening activity of demethylsuberosin may be due to the inhibition of the melanin synthesis by down-regulation of MITF, tyrosinase, TRP-1 and TRP-2 expression. Thus, our results provide evidence that demethylsuberosin might be useful as a potential skin-whitening agent.

• Journal of Microbiology and Biotechnology
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• v.33 no.4
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• pp.463-470
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• 2023

This study confirmed the change in functional composition and alcohol-induced acute liver injury in Aloe arborescens after fermentation. An acute liver injury was induced by administration of ethanol (3 g/kg/day) to C57BL/6J mice for 5 days. A fermented A. arborescens Miller leaf (FAAL) extract was orally administered 30 minutes before ethanol treatment. After fermentation, the emodin content was approximately 13 times higher than that of the raw material. FAAL extract significantly attenuated ethanol-induced aspartate aminotransferase, alanine aminotransferase, and triglyceride increases in serum and liver tissue. Histological analysis revealed that FAAL extract inhibits inflammatory cell infiltration and fat accumulation in liver tissues. The cytochrome P450 2E1, superoxide dismutase, and glutathione (GSH), which involved in alcohol-induced oxidative stress, were effectively regulated by FAAL extract in serum and liver tissues, except for GSH. FAAL also maintained the antioxidant defense system by upregulating heme oxygenase 1 and nuclear factor erythroid 2-related factor 2 protein expression. In addition, FAAL extract inhibited the decrease in alcohol dehydrogenase and aldehyde dehydrogenase activity, which promoted alcohol metabolism and prevented the activation of inflammatory response. Our results suggest that FAAL could be used as a potential therapeutic agent for ethanol-induced acute liver injury.

• Genomics & Informatics
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• v.13 no.3
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• pp.81-85
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• 2015

Molecular characterization technology in genetically modified organisms, in addition to how transgenic biotechnologies are developed now require full transparency to assess the risk to living modified and non-modified organisms. Next generation sequencing (NGS) methodology is suggested as an effective means in genome characterization and detection of transgenic insertion locations. In the present study, we applied NGS to insert transgenic loci, specifically the epidermal growth factor (EGF) in genetically modified rice cells. A total of 29.3 Gb (${\sim}72{\times}coverage$) was sequenced with a $2{\times}150bp$ paired end method by Illumina HiSeq2500, which was consecutively mapped to the rice genome and T-vector sequence. The compatible pairs of reads were successfully mapped to 10 loci on the rice chromosome and vector sequences were validated to the insertion location by polymerase chain reaction (PCR) amplification. The EGF transgenic site was confirmed only on chromosome 4 by PCR. Results of this study demonstrated the success of NGS data to characterize the rice genome. Bioinformatics analyses must be developed in association with NGS data to identify highly accurate transgenic sites.

• Korean Journal of Pharmacognosy
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• v.52 no.2
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• pp.92-98
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• 2021

Gryllus bimaculatus extract (GbE) have reported that anti-inflammatory activity by suppression of pro-inflammatory cytokines. However, the effects of fermented Gryllus bimaculatus extract (FGbE) have not yet been investigated. In this study, we evaluated the anti-inflammatory and anti-wrinkle effect of the fermented Gryllus bimaculatus extracts using Bacillus subtilis (JB PMB-18) in RAW264.7 cells. Both GbE and FGbE exerted no cytotoxic effects until 1000 ㎍/mL concentration. FGbE decreased NO production and decreased iNOS and COX-2 mRNA levels in a concentration-dependent manner. In addition, the protein production of inflammatory cytokines TNF-α, IL-1β and IL-6 was effectively reduced compared to the GbE. Inhibitory activities of elastase and collagenase associated with skin wrinkle improvement were measured to be 45% and 69%, respectively, at a concentration of 500 ㎍/mL in FGbE. From these results, FGbE can be used as a health functional food and skin functional cosmetic materials for preventing inflammatory diseases because it has excellent anti-inflammatory and anti-wrinkle effects.

• Journal of Magnetics
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• v.15 no.3
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• pp.112-115
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• 2010

We have investigated a surfactant-assisted sonochemical approach to produce monodisperse $Fe_3O_4$ nanoparticles (NPs). The non-ionic surfactant Igepal CO-520 (Poly(oxyethylene)(5) nonylphenyl ether) has been used for the preparation of NPs and the effects on the NP size, size distribution, and magnetic properties have been studied. The $Fe_3O_4$ NPs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM). The results reveal that the NPs prepared by a Igepal CO-520-assisted sonochemical method exhibit a narrow range of size distributions and a high monodispersity compared to the NPs from the conventional sonochemical method. The analysis of NPs prepared in the presence of the surfactant suggested that it could be used not only as a protector to prevent the oxidation of Fe (II), but also as a controller to vary the size of the NPs.

• Journal of the Korea Furniture Society
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• v.28 no.2
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• pp.111-117
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• 2017

Recently, as people's interest in wood has increased, the use of wood as household and landscape decking materials has increased. As the deck material, imported wood such as synthetic wood, Ipe, and Malas was used in addition to the existing preserved wood, but recently deck use has been activated as part of the activation of domestic materials. As an important quality factor in the selection of such decking materials, various durability along with weatherability for long - term use is required for maintenance. Generally used tropical hardwoods have excellent weatherability and durability without additional preservative treatment. However, the domestic larch is a wood species with a higher specific gravity and durability than ordinary conifers. However, it has not yet been used as a deck material due to lack of comparative studies on its characteristics. Therefore, hardness and durability of wood were measured using six specimens of Ipe, Massaranduba, Malas, Douglas-fir, Larch and Torrefied-Larch. Density Profile was used to measure the density, and Brinell hardness test and resistance test against momentary impact were carried out for the test of resistance to static load. Also, The hardness and durability of wood were measured by castor test with resistance test against dynamic load, as well as, nail down test by experiment on surface hardness and durability. As a result of the experiment, the hardness was increased in proportion to the density, and it was confirmed that the imported lumber was harder and durable than the domestic larch.

• Restorative Dentistry and Endodontics
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• v.40 no.1
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• pp.1-13
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• 2015

Advancements in bio-ceramic technology has revolutionised endodontic material science by enhancing the treatment outcome for patients. This class of dental materials conciliates excellent biocompatibility with high osseoconductivity that render them ideal for endodontic care. Few recently introduced bio-ceramic materials have shown considerable clinical success over their early generations in terms of good handling characteristics. Calcium enriched mixture (CEM) cement, Endosequence sealer, and root repair materials, Biodentine and BioAggregate are the new classes of bio-ceramic materials. The aim of this literature review is to present investigations regarding properties and applications of CEM cement in endodontics. A review of the existing literature was performed by using electronic and hand searching methods for CEM cement from January 2006 to December 2013. CEM cement has a different chemical composition from that of mineral trioxide aggregate (MTA) but has similar clinical applications. It combines the biocompatibility of MTA with more efficient characteristics, such as significantly shorter setting time, good handling characteristics, no staining of tooth and effective seal against bacterial leakage.

• Journal of the Korean Wood Science and Technology
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• v.34 no.3
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• pp.38-45
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• 2006

The main objective of this study is the improvement of the interfacial adhesion of RHF-polypropylene (PP) bio-composites through NaOH and acetic acid treated RHF. After manufacturing of untreated and NaOH and acetic acid treated RHF filled PP bio-composites, the effect on interfacial adhesion of bio-composites was investigated. Tensile strength of the bio-composites made from treated RHF with NaOH and acetic acid was higher than that of the untreated bio-composites. The RHF surface before and after NaOH and acetic acid treatment was clearly confirmed by scanning electron microscopy (SEM) micrograph. It was found that both treatments result in a removal of impurity materials of RHF surface by SEM micrographs. The chemical structures of untreated and NaOH and acetic acid treated RHF were confirmed by fourier transform infrared (FTIR). The crystallization structure and crystallinity of non-treated, NaOH and acetic acid treated RHF were investigated by wide-angle X-ray scattering (WAXS).

• Journal of the Korean Wood Science and Technology
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• v.46 no.2
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• pp.189-201
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• 2018

Intumescent system is a highly effective flame retardant technology that takes advantage of the mechanism of foaming and carbonization. In order to materialize Intumescent system, it is necessary to use reinforcement material to improve the strength of the material. In this study, we used kenaf as a natural fiber to manufacture intumescent/EVA (ethylene vinyl acetate) composites to improve mechanical and flame retardant performance. Finally two materials with different particle shape are applied to one system. Therefore, the influence factors of the particles with different shapes on the composite material were analyzed based on the tensile test. For this purpose, we have used the tensile strength analysis model and confirmed that it can only act as a partial strength reinforcement due to weak binding force between the matrix and particles. In the combustion characteristics analysis using cone calorimeter and UL 94, the combustion characteristics were enhanced as the content of Intuemscent was increased. As the content of kenaf increased, combustion characteristics were strengthened and carbonization characteristics were weakened. Through the application of kenaf, it can be confirmed that elastic modulus improvement and combustion characteristics can be strengthened, which confirmed the possibility of development of environmentally friendly flame retardant materials.

• Elastomers and Composites
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• v.54 no.4
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• pp.279-285
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• 2019

Bio-based polyester polyols were synthesized using esterification with azelaic acid, sebacic acid, and 1,3-propanediol. Polyurethanes were prepared using chain extenders (1,4-Butanediol, 1,3-Propanediol, and isosorbide) and 4,4'-diphenylmethane diisocyanate with a mixing ratio of 1:1:1.1. Subsequently, the properties of the polymers prepared using the different chain extenders were compared. The synthesis of polyurethane was confirmed by FT-IR, TGA, and GPC. The mechanical properties (hardness, ball rebound, and tensile strength) of the materials were analyzed using shore A tester, taber abrasion, and UTM. heat, chemical, and water resistances of the prepared materials were measured by comparing the tensile strengths according to external changes.