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51.
Eui-Cheol Shin Jin Hwan Lee Chung Eun Hwang Byong Won Lee Hyun Tae Kim Jong Min Ko In-Yeoul Baek Ji Hyeon Shin Sang Hae Nam Weon Taek Seo Kye Man Cho 《Food science and biotechnology》2014,23(2):531-538
Changes in β-glycosidase activity, total phenolic and isoflavone contents, and antioxidant activities during the fermentation of brown soybeans (Galmi) fermented food cheonggukjang by the potential probiotic Bacillus subtilis CSY191 were investigated. The total phenolic and isoflavone-glycoside and -aglycone contents as well as ABTS radical scavenging activity and FRAP assays of extracts increased, but malonylglycoside content decreased after a steaming process. It was found that fermentation enhanced the total phenolic and isoflavone-aglycone and -malonylglycoside contents, corresponding to antioxidant activities increased, but isoflavone-glycoside content decreased. The highest levels of daidzein, glycitein, and gensitein were present at concentrations of 156.5 μg/g, 10.2 μg/g, and 2.5 μg/g after 48 h of fermentation. In addition, ABTS radical scavenging activity and FRAP assay increased significantly during fermentation. We suggest that the high antioxidant activity of cheonggukjang of brown soybeans might be related to the markedly higher levels of total phenolic content and isoflavone-aglycones achieved during fermentation. 相似文献
52.
Daegun Kang Taiuk Rim Chang‐Ki Baek M. Meyyappan Jeong‐Soo Lee 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(18):3795-3802
The photoresponse characteristics of In2Se3 nanowire photodetectors with the κ‐phase and α‐phase structures are investigated. The as‐grown κ‐phase In2Se3 nanowires by the vapor‐liquid‐solid technique are phase‐transformed to the α‐phase nanowires by thermal annealing. The photoresponse performances of the κ‐phase and α‐phase In2Se3 nanowire photodetectors are characterized over a wide range of wavelengths (300–900 nm). The phase of the nanowires is analyzed using a high‐resolution transmission microscopy equipped with energy dispersive X‐ray spectroscopy and X‐ray diffraction. The electrical conductivity and photoresponse characteristics are significantly enhanced in the α‐phase due to smaller bandgap structure compared to the κ‐phase nanowires. The spectral responsivities of the α‐phase devices are 200 times larger than those of the κ‐phase devices. The superior performance of the thermally phase‐transformed In2Se3 nanowire devices offers an avenue to develop highly sensitive photodetector applications. 相似文献
53.
Kwang-Chon Kim Seung Hyub Baek Hyun Jae Kim Jin Dong Song Jin-Sang Kim 《Journal of Electronic Materials》2012,41(10):2795-2798
Epitaxial CdTe thin films were grown on GaAs/Si(001) substrates by metalorganic chemical vapor deposition using thin GaAs as a buffer layer. The interfaces were investigated using high-resolution transmission electron microscopy and geometric phase analysis strain mapping. It was observed that dislocation cores exist at the CdTe/GaAs interface with periodic distribution. The spacing of the misfit dislocation was measured to be about 2?nm, corresponding to the calculated spacing of a misfit dislocation (2.6?nm) in CdTe/Si with Burgers vector of a[110]/2. From these results, it is suggested that the GaAs buffer layer effectively absorbs the strain originating from the large lattice mismatch between the CdTe thin film and Si substrate with the formation of periodic structural defects. 相似文献
54.
Se Eun Ha Brian G. Jorgensen Lai Wei Byungchang Jin Min-Seob Kim Sandra M. Poudrier Rajan Singh Allison Bartlett Hannah Zogg Sei Kim Gain Baek Masaaki Kurahashi Moon-Young Lee Yong-Sung Kim Suck-Chei Choi Kent C. Sasse Samuel J. S. Rubin Andres Gottfried-Blackmore Laren Becker Aida Habtezion Kenton M. Sanders Seungil Ro 《International journal of molecular sciences》2022,23(9)
Metalloendopeptidase ADAM-Like Decysin 1 (ADAMDEC1) is an anti-inflammatory peptidase that is almost exclusively expressed in the gastrointestinal (GI) tract. We have recently found abundant and selective expression of Adamdec1 in colonic mucosal PDGFRα+ cells. However, the cellular origin for this gene expression is controversial as it is also known to be expressed in intestinal macrophages. We found that Adamdec1 mRNAs were selectively expressed in colonic mucosal subepithelial PDGFRα+ cells. ADAMDEC1 protein was mainly released from PDGFRα+ cells and accumulated in the mucosal layer lamina propria space near the epithelial basement membrane. PDGFRα+ cells significantly overexpressed Adamdec1 mRNAs and protein in DSS-induced colitis mice. Adamdec1 was predominantly expressed in CD45− PDGFRα+ cells in DSS-induced colitis mice, with only minimal expression in CD45+ CD64+ macrophages. Additionally, overexpression of both ADAMDEC1 mRNA and protein was consistently observed in PDGFRα+ cells, but not in CD64+ macrophages found in human colonic mucosal tissue affected by Crohn’s disease. In summary, PDGFRα+ cells selectively express ADAMDEC1, which is localized to the colon mucosa layer. ADAMDEC1 expression significantly increases in DSS-induced colitis affected mice and Crohn’s disease affected human tissue, suggesting that this gene can serve as a diagnostic and/or therapeutic target for intestinal inflammation and Crohn’s disease. 相似文献
55.
Ensanya A. Abou Neel Azadeh Kiani Sabeel P. Valappil Nicky M. Mordan Song-Yi Baek Kazi M. Zakir Hossain Reda M. Felfel Ifty Ahmed Kamini Divakarl Wojciech Chrzanowski Jonathan C. Knowles 《应用聚合物科学杂志》2019,136(32):47832
This study aimed to formulate antibacterial dental adhesives. Phosphate-substituted methacrylate adhesives were modified with 0–20 wt % copper-doped glass microparticles. Two shapes of microparticles were used: regular shaped (microspheres) and irregular shaped (microparticles). The morphology/composition, roughness, monomer conversion (DC%), thermogravimetric analysis, and antibacterial action against S. mutans and P. aeruginosa and ion release were investigated. The results showed that microspheres produced adhesives with a relatively smoother surface than microparticles did. The DC% of adhesives increased with increasing glass filler content. Filled adhesives showed polymer decomposition at ~315 °C and glass melting at 600–1000 °C. The weight loss percent of adhesives decreased with increasing weight percent of fillers. Glass microparticles at 0–20 wt % significantly increased the antibacterial action of adhesives against both bacteria. Glass microspheres at 0–5 wt % significantly increased the antibacterial action of adhesives against both bacteria. Only 20 wt % microparticle-filled adhesive showed an inhibition zone similar to tobramycin (positive control). Microparticle-filled adhesives (with >5 wt % filler) significantly reduced S. mutans more than their microsphere counterparts. Microsphere-filled adhesives (with ≤5 wt % filler) significantly reduced P. aeruginosa more than their microparticle counterparts. Microsphere-filled adhesives showed higher Cu release than their microparticle counterparts. Accordingly, phosphate-substituted methacrylate filled with glass could be used as an antibacterial adhesive. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47832. 相似文献
56.
Jeom-In Baek Chong Kul Ryu Tae Hyoung Eom Joong Beom Lee Won-Sik Jeon Jongheop Yi 《Korean Journal of Chemical Engineering》2011,28(11):2211-2217
Chemical-looping combustion (CLC) of syngas has a potential to generate power economically with achieving the inherent carbon dioxide capture. An oxygen carrier with high reactivity and excellent physical properties would make CLC technology more competitive. In this work, oxygen carrier with 70 wt% NiO was prepared by spray drying technique. The prepared oxygen carrier had excellent physical properties for fluidized-bed application of CLC process. The reactivity of the oxygen carrier in repeated reduction-oxidation was measured by thermogravimetric analyzer with simulated syngas. Oxygen carrier calcined at 1,100 °C showed high oxygen transfer capacity of 14.7 wt%, utilizing 98% of the transferable oxygen. Oxygen transfer capacity and oxygen transfer rate was increased with the increase of reaction temperature, and the highest oxygen transfer rate was observed when about half of the transferable oxygen reacted with syngas. The reduction rate of the syngas (mixture of H2 and CO) appeared to be approximately the sum of the reaction rate of each fuel gas. The experimental results indicated that the spray-dried NiO oxygen carrier prepared in this work could be a good quality oxygen carrier for the CLC of syngas. 相似文献
57.
Nak‐Yun Sung Eui‐Baek Byun Sun‐Kyu Kwon Young‐Choon Yoo Pil‐Mun Jung Jae‐Hun Kim Jong‐Il Choi Mee‐Ree Kim Ju‐Woon Lee 《应用聚合物科学杂志》2011,120(4):2034-2040
We conducted this study to examine the changes in the molecular structure and physiological activities of silk sericin after γ irradiation. Sericin from Bombyx mori was extracted with an Na2CO3 solution. The molecular weight distribution of sericin increased in the gel permeation chromatography and sodium dodecyl sulfate/polyacrylamide gel electrophoresis results as the irradiation dose increased. Circular dichroism data also revealed that the α‐helix contents decreased with the irradiation dose. Ultraviolet absorption was shown a different pattern between the irradiated and unirradiated sericin. However, the Fourier transform infrared spectrum was not changed in all of the groups. Furthermore, the irradiated sericin was significantly increased in 2,2‐diphenyl‐1‐picryl‐hydrazil radical scavenging, and the tyrosinase inhibitory activities increased with irradiation dose. Therefore, γ irradiation was an effective method for producing high‐molecular‐weight sericin and for developing functional foods and cosmetics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
58.
Because of poor mechanical strength, applications of electrospun polystyrene (PS) fibrous mats are quite limited. The introduction of various concentrations of poly (butylacrylate) adhesives (PBAs) into PS solutions led to the fabrication of point‐bonded electrospun PS fibrous mats with good mechanical strength. The morphologies of PS/PBA fibers with varying PBA content (0?50 wt%) were investigated using scanning electron microscopy (SEM), and the results were compared with pure PS and PBA fibers fabricated with various solvents. SEM images indicated that point‐bonded PS/PBA fibers were uniformly distributed with an average diameter of 1–2 μm. On increasing concentration of PBA up to 20 wt%, porous PS/PBA fibrous mats were obtained. However, solid films were formed at very high concentrations of PBA. The Young's modulus and tensile strength of PS/PBA fibrous mats increased up to 52.4 and 2.7 MPa, respectively. The resultant enhancement of the mechanical properties of PS fibrous mats on addition of PBA increases the number of potential applications of these materials. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers 相似文献
59.
60.
Se-Jin Joo Hee-Jung Park Ji-Hae Park Jin-Gyeong Cho Ji-Hyun Kang Tae-Sook Jeong Hee Cheol Kang Dae-Young Lee Hack-Soo Kim Sang-Yo Byun Nam-In Baek 《International journal of molecular sciences》2014,15(9):16418-16429
Stems of Machilus japonica were extracted with 80% aqueous methanol (MeOH) and the concentrated extract was successively extracted with ethyl acetate (EtOAc), normal butanol (n-BuOH), and water. Six flavonoids were isolated from the EtOAc fraction: (+)-taxifolin, afzelin, (−)-epicatechin, 5,3''-di-O-methyl-(−)-epicatechin, 5,7,3''-tri-O-methyl-(−)-epicatechin, and 5,7-di-O-methyl-3'',4''-methylenedioxyflavan-3-ol. The chemical structures were identified using spectroscopic data including NMR, mass spectrometry and infrared spectroscopy. This is the first report of isolation of these six compounds from M. japonica. The compounds were evaluated for their diphenyl picryl hydrazinyl scavenging activity and inhibitory effects on low-density lipoprotein oxidation. Compounds 1 and 3–6 exhibited DPPH antioxidant activity equivalent with that of ascorbic acid, with half maximal inhibitory concentration (IC50) values of 0.16, 0.21, 0.17, 0.15 and 0.07 mM, respectively. The activity of compound 1 was similar to the positive control butylated hydroxytoluene, which had an IC50 value of 1.9 µM, while compounds 3 and 5 showed little activity. Compounds 1, 3, and 5 exhibited LDL antioxidant activity with IC50 values of 2.8, 7.1, and 4.6 µM, respectively. 相似文献