• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.153-158
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• 1984

From water extract of red ginseng, two new-type glucosides, $A:\;C_{12}H_{16}O_8\;and\;B:\;C_9H_{16}\;O_7,$ were isolated by fractionation with highly porous polymer ollowed by chromatography on silica gel in yields of 0.04 and $0.16\%,$ respectivley. The structures of A and B were elucidated by means of NMR and MS. Neither glucosides were detected in the extract of white ginseng and the mechanism of formation of A and B during the process of steaming will be discussed. The isolation and identification of saponins of corms (head of the root) of red ginseng are also reported.

• Journal of Life Science
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• v.18 no.3
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• pp.298-303
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• 2008

Using a phage peptide library approach, we have isolated a peptide ligand that binds to transferrin receptor on the surface of human melanoma cell, B16F10. The library was first screened twice by recovering internalized phages and was further screened three times by competitively eluting transferrin receptor-specific phages with human transferrin among the phages bound to the cell surface. The peptides displayed by the selected phages were fused to translocation and catalytic domain of Pseudomonas exotoxin to prepare recombinant toxins. After estimating cytotoxicity of each recombinant toxin toward B16F10 cell, seven clones were selected. Sequence analysis revealed that one of the clones displayed a peptide which had a significant sequence homology with human transferrin. The peptide was chemically synthesized and was shown to be functional in delivering cytotoxic agents into B16F10 cell via interaction with transferrin receptor.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.477-482
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• 2009

Inhibitory effect of skin and seed of three species grape cultivated in Korea on melanogenesis was investigated. Melanin generation was examined in $\alpha$-Melanin Stimulating Hormone-stimulated B16 cell, mouse melanoma, in the presence of samples. All skin sample did not show the inhibitory effect. Seed extract of Campbell early and Neo Muscat had negative effect on cell viability. When $50{\mu}g/ml$ seed extract of Muscat Bailey A was treated, amount of generated melanin and cell viability were $51.6{\pm}20.5%$ and $90.4{\pm}11.3%$ compared to control, respectively. Seed extract of Muscat Bailey A reduced the tyrosinase protein induced by $\alpha$-Melanin Stimulating Hormone, which suggests that inhibitory effect of seed extract of Muscat Bailey A on melanin is partly due to suppression of tyrosinase that is responsible for melanin production.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.63-63
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• 2018

본 연구에서는 80% 식물성 알코올을 추출 용매로 사용해 오디를 빛을 차단 후 실온에서 3일 간 추출하였다. 3회 여과한 후 최소 온도($40{\sim}60^{\circ}C$)에서 농축한 뒤 동결 건조하여 파우더 형태로 사용하였다. 오디(Morus alba)의 에탄올 추출물은 B16/F10 세포의 항산화 및 멜라닌 합성 억제 효과를 나타내었다. 멜라닌 함량과 세포 내 tyrosinase 활성을 Western blotting으로 측정 하였다. Tyrosinase와 tyrosinase-related protein (TRP) -1은 tyrosinase-related protein (TRP) -2보다 강력하게 억제되었으며, 이들 결과는 tyrosinase와 TRP-1은 흑갈색을 띠는 eumelanin의 생합성의 억제와 강한 상관관계가 있음을 보여 주었다. ${\alpha}$-melanocyte-stimulating hormone (${\alpha}$-MSH) 처리 한 B16/F10 흑색 종 세포에서 M. alba 에탄올 추출물은 멜라닌 생성 연관 단백질의 발현 및 멜라닌 생성이 용량 의존적으로 억제 하였다. 멜라닌 함량과 세포 내 tyrosinase 활성을 Western blotting으로 측정 하였다. 또한 DPPH와 SOD를 사용하여 항산화 활성을 분석하였고 총 폴리 페놀과 총 플라보노이드 함량을 측정 하였다. MTT assay 분석을 사용하여 M. alba 에탄올 추출물의 세포 독성을 측정 하였다. B16/F10 멜라닌 생성 세포의 tyrosinase 저해 활성 및 사멸 효과가 일반적으로 효과적이었다. 따라서 M. alba 에탄올 추출물은 항산화 및 미백 효과를 나타내며, 기능성 화장품의 천연 성분으로서 우수한 것으로 여겨진다.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.76-81
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• 2012

The objective of the present study was to evaluate the skin depigmentation effect of the extracts of three herbs, Carthamus tinctorius seed, Cyperus rotundus and Schizonepeta tenuifolia. Their effects on tyrosinase and melanin synthesis inhibitory action were assessed. We found that the C. tinctorius seed ethanol extracts reduced the tyrosinase activity and melanin formation of B16F10 melanoma cells. The C. tinctorius seed suppressed the expression in microphthalmia associated transcription factor (MITF), tyrosinase, tyrosinase related protein 1 (TRP-1), and tyrosinase related protein 2 (TRP-2) in B16F10 melanoma cells. These results show that C. tinctorius seed inhibited melanogenesis on the B16F10 melanoma cell. The underlying mechanism of C. tinctorius seed whitening activity may be the inhibition of tyrisinase, MITF, tyrosinase, TRP-1, and TRP-2 expression. The results suggested that C. tinctorius seed has considerable potential as a natural functional ingredient with a depigmentation effect.

• Biomolecules & Therapeutics
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• v.30 no.5
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• pp.465-472
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• 2022

Melanoma is one of the most aggressive skin cancers. Hypoxia contributes to the aggressiveness of melanoma by promoting cancer growth and metastasis. Upregulation of cyclin D1 can promote uncontrolled cell proliferation in melanoma, whereas stimulation of cytotoxic T cell activity can inhibit it. Epithelial mesenchymal transition (EMT) plays a critical role in melanoma metastasis. Hypoxia-inducible factor-1α (HIF-1α) is a main transcriptional mediator that regulates many genes related to hypoxia. CoCl₂ is one of the most commonly used hypoxia-mimetic chemicals in cell culture. In this study, inhibitory effects of IDF-11774, an inhibitor of HIF-1α, on melanoma growth and metastasis were examined using cultured B16F10 mouse melanoma cells and nude mice transplanted with B16F10 melanoma cells in the presence or absence of CoCl₂-induced hypoxia. IDF-11774 reduced HIF-1α upregulation and cell survival, but increased cytotoxicity of cultured melanoma cells under CoCl₂-induced hypoxia. IDF-11774 also reduced tumor size and local invasion of B16F10 melanoma in nude mice along with HIF-1α downregulation. Expression levels of cyclin D1 in melanoma were increased by CoCl₂ but decreased by IDF-11774. Apoptosis of melanoma cells and infiltration of cytotoxic T cells were increased in melanoma after treatment with IDF-11774. EMT was stimulated by CoCl₂, but restored by IDF11774. Overall, IDF-11774 inhibited the growth and metastasis of B16F10 melanoma via HIF-1α downregulation. The growth of B16F10 melanoma was inhibited by cyclin D1 downregulation and cytotoxic T cell stimulation. Metastasis of B16F10 melanoma was inhibited by EMT suppression.

• Journal of Broadcast Engineering
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• v.13 no.3
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• pp.388-400
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• 2008

This paper introduces a cost-effective method fur improving anchor picture quality of a multiview video coding scheme that is mainly based on chroma compensation. Proposed method is applied to both INTER $16{\times}16$ and SKIP modes in only anchor P-pictures. By testing using JVT common test conditions, simulation results show that proposed method can obtain the average BD-PSNR gains fur U and V as 0.136 dB and 0.127 dB, respectively, while maintaining almost same performance for Y (luminance). For the range of low bit-rates, it is observed that average BD-PSNR gains of Y, U, and V are 0.141 dB, 0.494 dB and 0.525 dB, respectively. Necessary computational complexity is very marginal because the number of anchor P-pictures is only 4.18% in comparison with whole coded sequences, however it can be found that the proposed method can significantly improve the coding efficiencies of color components.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.431-437
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• 2006

Aero-tolerant microorganisms were isolated from healthy Koreans over the age of 95 years. The microorganisms were then identified based on their morphological and biochemical characteristics and 16S rDNA sequences. The growth properties of the isolated strains were investigated in kimchi. The characteristics of kimchi containing the microorganisms were studied microscopically, physicochemically, and organoleptically. Among 7 aero-tolerant strains, a strain with a 16S rDNA sequence exhibiting 99% homology with Bifidobacterim animalis strain B83 was selected and named B. animalis DY-64. The new strain showed a better acid resistance and salt resistance (p<0.05) than B. animalis ATCC 25527. After 15 days of fermentation in kimchi, the viability of B. animalis DY-64 was about 10%, and the kimchi had a better overall edible quality than conventional kimchi. Thus, it was found that the application of B. animalis DY-64 to kimchi preparation produced a good overall edible quality.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.63-67
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• 2000

본 논문에서는 IEEE 802.11a 무선 LAN에 적합한 16QAM/OFDM 시스템의 성능을 AWGN과 two-ray 다중 경로 페이딩 채널에서 시뮬레이션을 통하여 분석하고 성능 향상을 위한 방법으로 비터비 복호를 하는 길쌈 부호와 단일 탭의 LMS 등화기를 사용한다. 길쌈 부호를 사용하면 AWGN과 다중 경로 페이딩 채널에서 각각 경판정(hard-decision)은 2dB, 6 dB, 연판정(soft-decision)은 4.5 dB, 10 dB의 이득을 얻는다. 또한 다중 경로 페이딩 환경에서 경판정 비터비 복호와 단일 탭의 LMS 등화기를 함께 사용하는 경우에는 경판정 복호만을 사용하는 경우보다 5 dB 향상됨을 알 수 있다.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.51-59
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• 2004

Phylogenetic relationships were analyzed among bumblebees using a portion of mitochondrial (mt) 16S ribosomal RNA (16S rRNA). Eight species of true bumblebees and one species of cuckoo bumblebee (Bombini, Apidae), collected from Korea were included in the analysis. Also, one species of true bumblebee imported from several foreign countries for pollination was included. The length of mt 16S rRNA sequence ranged from 496 bp to 508 bp and sequence divergence ranged from 1.4％ (7 bp) to 15.49％ (77bp). As expected, a high A＋T content was observed (78.5％ on average). According to the phylogeny tree derived from parsimony and maximum likelihood analysis, a monphyletic Bombus species, excluding a single cuckoo bumblebee, Psithyrus coreanus, was obtained, but the bootstrap estimate at the node supporting the monophyletic group was very weak (40％ or 46％), suggesting a very close relationship of the cuckoo bumblebee to the true bumblebee. Within Bombus species belonging to identical subgenera subgeneric specific clustering was formed with high bootstrap values, implying validity of the subgeneric names of each species: Pyrobombus for B. ardens and B. modeatus; Megabombus for B. consobrinus wittenburgi and B. koreanus; and Bombus s. str. for B. ignitus, B. hypocrita sapporoensis, and B. terrestris.