• Title/Summary/Keyword: optimum properties

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Enhanced Transdermal Delivery of Drug Compounds Using Scalable and Deformable Ethosomes (에토좀 입자크기와 멤브레인 특성 조절을 통한 약물의 경피흡수능 향상)

  • An, Eun-Jung;Shim, Jong-Won;Choi, Jang-Won;Kim, Jin-Woong;Park, Won-Seok;Kim, Han-Kon;Park, Ki-Dong;Han, Sung-Sik
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.36 no.2
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    • pp.105-113
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    • 2010
  • This study introduces a flexible approach to enhance skin permeation by using ethosomes with deformable lipid membranes as well as controllable sizes. To demonstrate this, a set of ethosomes encapsulating an anti-hair loss ingredient, Triaminodil$^{TM}$, as a model drug, were fabricated with varying their size, which was achieved by solely applying the different level of mechanical energy, while maintaining their chemical composition. After characterization of the ethosomes with dynamic light scattering, transmission electron microscopy, and deformability measurements, it was found that their membrane deformability depended on the particle size. Moreover, studies on in vitro skin permeation and murine anagen induction allowed us to figure out that the membrane deformability of ethosomes essentially affects delivery efficiency of Triaminodil$^{TM}$ through the skin. It was noticeable in our study that there existed an optimum particle size that can not only maximize the delivery of the drug through the skin, but also increase its actual dermatological activity. These findings offer a useful basis for understanding how ethosomes should be designed to improve delivery efficiency of encapsulated drugs therein in the aspects of changing their length scales and membrane properties.

Purification and Characterization of ($Ca^{2+}$+$Mg^{2+}$)-ATPase of Sarcoplasmic Reticulum from Rat Skeletal Muscle (쥐 근소포체의 ($Ca^{2+}$+$Mg^{2+}$)-ATPase의 분리정제와 그 효소특성에 관하여)

  • Lee, Jong-Soon;Ha, Doo-Bong;Chung, Chin-Ha
    • The Korean Journal of Zoology
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    • v.28 no.1
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    • pp.31-43
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    • 1985
  • The $(Ca^{2+}+Mg^{2+})$-ATPase has been purified homogeneously from sarcoplasmic reticulum of rat skeletal muscle by sucrose density gradient centrifugation. The purified enzyme has a molecular weight of 115,000 as judged by polyacrylamide gel electrophoresis in the presence of sodium dedecyl sulfate, and therefore has the same size of the enzyme in rabbit and chick skeletal muscle. $Ca^{2+}, Mg^{2+}, Fe^{2+}, Co^{2+}, and Mn^{2+}$ at 50 $\\muM$ show stimulatory effect on the ATP-ase, while $Zn^{2+}, Cu^{2+}, and Hg^{2+}$ inhibit it at the same concentration. The ATPase activity is insensitive to antimalarial drugs such as quinine and quinacrine, but is sensitive to inhibition by p-hydroxymecurie benzoate and phenylmethylsulfonylfluoride. The enzyme has optimum pH of 6 to 7 and Km value for ATP is estimated to be 98 $\\muM$. Thus, a number of biochemical properties of this enzyme appear to be different from those of the enzyme that have been isolated from rabbit skeletal muscle. The $(Ca^{2+}+Mg^{2+})$-ATPase appears to be selectively degraded in microsomal fraction. The activity of metalloendoprotease is evident in the microsomal preparation when assayed by radioactively labeled protein substrate, such as $^{3}H-casein and $^{125}I$-insulin. However, it is presently unclear whether the metalloendoprotease is responsible for the degradation of the $(Ca^{2+}+Mg^{2+})$-ATPase.

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Direct Growth of CNT on Cu Foils for Conductivity Enhancement and Their Field Emission Property Characterization (전도성 향상을 위한 구리호일 위 CNT의 직접성장 및 전계방출 특성 평가)

  • Kim, J.J.;Lim, S.T.;Kim, G.H.;Jeong, G.H.
    • Journal of the Korean Vacuum Society
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    • v.20 no.2
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    • pp.155-163
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    • 2011
  • Carbon nanotubes (CNT) have been attracted much attention since they have been expected to be used in various areas by virtue of their outstanding physical, electrical, and chemical properties. In order to make full use of their prominent electric conductivity in some areas such as electron emission sources, device interconnects, and electrodes in energy storage devices, direct growth of CNT with vertical alignment is definitely beneficial issue because they can maintain mechanical stability and high conductivity at the interface between substrates. Here, we report direct growth of vertically aligned CNT (VCNT) on Cu foils using thermal chemical vapor deposition and characterize the field emission property of the VCNT. The VCNT's height was controlled by changing the growth temperature, growth time, and catalytic layer thickness. Optimum growth condition was found to be $800^{\circ}C$ for 20 min with acetylene and hydrogen mixtures on Fe catalytic layer of 1 nm thick. The diameter of VCNT grown was smaller than that of usual multi walled CNT. Based on the result of field emission characterization, we concluded that the VCNT on Cu foils can be useful in various potential applications where high conductivity through the interface between CNT and substrate is required.

Synthesis of vertically aligned thin multi-walled carbon nanotubes on silicon substrates using catalytic chemical vapor deposition and their field emission properties (촉매 화학 기상 증착법을 사용하여 실리콘 기판위에 수직 정렬된 직경이 얇은 다중층 탄소나노튜브의 합성과 그들의 전계방출 특성)

  • Jung, S.I.;Choi, S.K.;Lee, S.B.
    • Journal of the Korean Vacuum Society
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    • v.17 no.4
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    • pp.365-373
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    • 2008
  • We have succeeded in synthesizing vertically aligned thin multi-walled carbon nanotubes (VA thin-MWCNTs) by a catalytic chemical vapor deposition (CCVD) method onto Fe/Al thin film deposited on a Si wafers using an optimum amount of hydrogen sulfide ($H_2S$) additive. Scanning electron microscope (SEM) images revealed that the as-synthesized CNT arrays were vertically well-oriented perpendicular to the substrate with relatively uniform length. Transmission electron microscope (TEM) observations indicated that the as-grown CNTs were nearly catalyst-free thin-MWCNTs with small outer diameters of less than 10nm. The average wall number is about 5. We suggested a possible growth mechanism of the VA thin-MWCNT arrays. The VA thin-MWCNTs showed a low turn-on electric field of about $1.1\;V/{\mu}m$ at a current density of $0.1\;{\mu}A/cm^2$ and a high emission current density about $2.5\;mA/cm^2$ at a bias field of $2.7\;V/{\mu}m$. Moreover, the VA thin-MWCNTs presented better field emission stability without degradation over 20 hours (h) at the emission current density of about $1\;mA/cm^2$.

Physical Properties of Dredged Sand Treated by Washing and Sorting Dredged Soil (하천준설토를 세척 선별한 준설모래의 물리적 특성)

  • Lee, Yun-Seong;Lee, Sang-Soo;Song, Ha-Young;Bae, Kee-Sun;Lee, Sung-Bok;Lee, Do-Heun
    • Land and Housing Review
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    • v.1 no.1
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    • pp.35-42
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    • 2010
  • Most of the dredged sand generated from the sewage pipe maintenance project and the government's four-river project are disposed depending on abandonment and filling-up. This is caused by the lack of related recycling technology using dredged sand appropriately and high absorption rate and micro-particles of dredged sand producted from existing sand production system. Thus, this study carried out a quality assessment for the dredged sand produced through the optimum washing and sorting system supplementing problems of existing dredged sand production system as a part of research to examine performance of removing micro-particles and foreign substances. As a result of the assessment, the dredged sand produced through the cleaning and sorting system showed a wide quality improvement effect in absorption rate, 0.08 mm sieve pass amount, clay lump volume and organic impurity content, and it turned out to satisfy both the quality standards of this study, KS F 2573(recycled aggregate for concrete) and KS F 2526(aggregate for concrete) so it could be confirmed that it would be able to be used as an aggregate for concrete in the future.

Quality characteristics of Hijikia fusiforme extracts with different extraction method (추출방법에 따른 톳 추출물의 품질특성)

  • Kwon, Yu-Ri;Youn, Kwang-Sup
    • Food Science and Preservation
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    • v.22 no.1
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    • pp.70-77
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    • 2015
  • The physiological properties of water extracts from Hizikia fusiformis extracted using different extraction methods (water extraction, WE; autoclave extraction, AE; high pressure extraction, HPE) were investigated. The freeze-dried powder yields from HPE, AE and WE were 29.33, 27.84 and 23.63%, respectively. The $L^*$ and $b^*$ color values were higher in WE, while the $a^*$ color values were higher in WE and AE. The total sugar content of AE (60.14%) was higher than those of WE (47.10%), HPE (40.97%). The reducing sugar content (7.88%) and protein content (42.83%) of AE was higher than those of WE, and HPE. The uronic acid (5.04%), total free amino acid (785.19 mg/g), taurine (19.16 mg/g), aspartic acid (66.63 mg/g), asparagine (204.84 mg/g), alanine (188.87 mg/g) and ammonium chloride (243.91 mg/g) contents, however, were the highest in HPE. Additionally, the crude polysaccharide yield was higher in HPE (4.75%) than in AE and WE, and the crude saccharide (fucose, galactose, glucose, xylose and fucose) yields were higher in AE. It can be concluded that optimum conditions for the efficient extraction of Hizikia fusiformis depending on components are high pressure and a lower temperature than in the typical process.

Quality characteristics of outer leaves of Kimchi cabbage according to various blanching treatment conditions (국내산 배추 우거지의 blanching 처리에 따른 품질 특성)

  • Hong, Joo-Heon;Hwang, Tae-Young
    • Food Science and Preservation
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    • v.23 no.7
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    • pp.939-944
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    • 2016
  • The aim of this study was to establish an optimum blanching condition for outer cabbage leaves to increase utilization of the byproduct. Outer leaves of Kimchi cabbages were cut to size ($4{\times}4cm$) and blanched at 80, 90, $100^{\circ}C$ for 1, 3, and 5 min. Subsequently, weight loss, pH, total bacteria, coliform and texture properties were investigated. Sensory evaluation of a ready-to-cook soup prepared from blanched outer leaves was investigated to determine whether the quality of the blanched outer leaves was acceptable. Both weight loss and pH of outer leaves of Kimchi cabbage were increased by blanching. Compared to raw samples, total bacterial counts decreased and coliform bacteria were not detected. The hardness of raw leaf samples was $1.5kg{\cdot}force$ (N). Sample hardness was 18.7~21.7% lower after blanching for 3 min and 34.8~36.7% after blanching for 5 min. Sensory evaluation of outer leaves blanched at $100^{\circ}C$ for 5 min revealed significant differences from the other treatments (p<0.05). In addition, sensory evaluation scores for texture and appearance of outer leaves blanched at $100^{\circ}C$ for 3 min were higher than those for commercially available products. The results of this study indicate that blanching can be effective for developing a food product from the outer leaves of Kimchi cabbage.

Extraction Conditions and Green Index of Green Pigments from Discolored Garlic (녹변된 마늘의 색소 추출 조건과 Green Index)

  • Hwang, Jin-Bong;Ha, Jae-Ho;Shin, Dong-Bin;Park, Wan-Soo;Nahmgung, Bae;Lee, Young-Chun
    • Korean Journal of Food Science and Technology
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    • v.37 no.4
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    • pp.678-684
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    • 2005
  • Extraction conditions, spectrometric, and sensory properties of pigment extracts from green discolored garlic (GDG) were studied for development of green index to evaluate degree of green discoloration of garlic. GDG pigments were extracted using polar solvents, such as methanol, ethanol, and water. Methanol with 1% HCl resulted in highest extraction of green pigments. Extraction of pigments was affected by temperature, and extracted pigments were partially destroyed at high temperatures. Optimum conditions for extraction of green pigments were $20^{\circ}C$ for 30 min. Because green pigments are unstable at room temperature, and no method has been reported to evaluate degree of green discoloration of garlic, color chart was designed by mixing varying amounts of control and GDG. High correlation was observed between sensory scores and "a" value of color chart samples (y=-3.465x - 11.676) with $R^2$ of 0.993. Green index (GI) was developed based on linear regression equation between sensory scores and "a" values. Sensory panel recognized green discoloration of garlic at $GI{\geq}3.0$. GI developed in this study could be utilized to evaluate degree of green discoloration of garlic during cold storage and distribution of garlic.

Preparation of Flakes by Extrusion Cooking Using Barley Broken Kernels (보리 파쇄립을 이용한 압출성형에 의한 후레이크 제조)

  • Choi, Hee-Don;Seog, Ho-Moon;Choi, In-Wook;Park, Mi-Won;Ryu, Gi-Hyung
    • Korean Journal of Food Science and Technology
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    • v.36 no.2
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    • pp.276-282
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    • 2004
  • Barley flakes were developed by extrusion cooking using broken kernels, by-products of the barley pearling process. Broken kernels from both non-waxy and waxy barley broken kernels were sufficiently gelatinized at the barrel temperature of over $100^{\circ}C$ and the moisture content of broken kernels of over 35%. Cutting and flaking roll separating properties of pellets prepared from non-waxy barley broken kernels were better than those of waxy barley broken kernels. Characteristics of pellets prepared by extrusion cooking in different mixing ratios of non-waxy and waxy barley broken kernels were investigated. As the mixing ratio of waxy barley broken kernels increased, RVA peak viscosity, apparent viscosity, and yield stress of prepared pellets decreased, while flow behavior index increased. As the mixing ratio of waxy barley broken kernels increased, compressive strength and bulk density of deep-fat fried flakes drastically decreased, and the size of air cells on cross-section increased, and thickness of cell-constituting bodies decreased. Sensory evaluation results showed that acceptability for texture and taste of flakes inclosed as the mixing ratio of waxy barley broken kernels increased, and optimum mixing level of waxy barley broken kernels appeared to be 30-40%.

Characterization of Sporulation-Specific Glucoamylase of Saccharomyces diastaticus (Saccharomyces diastaticus의 포자형성 특이 글루코아밀라제의 특성)

  • Kim, Eun-Ju;Ahn, Jong-Seog;Kang, Dae-Ook
    • Journal of Life Science
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    • v.20 no.5
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    • pp.683-690
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    • 2010
  • The yeast strains of Saccharomyces diastaticus produce one of three isozymes of an extracellular glucoamylase I, II or III, a type of exo-enzyme which can hydrolyse starch to generate glucose molecules from non-reducing ends. These enzymes are encoded by the STA1, STA2 and STA3 genes. Another gene, sporulation-specific glucoamylase (SGA), also exists in the genus Saccharomyces which is very homologous to the STA genes. The SGA has been known to be produced in the cytosol during sporulation. However, we hypothesized that the SGA is capable of being secreted to the extracellular region because of about 20 hydrophobic amino acid residues at the N-terminus which can function as a signal peptide. We expressed the cloned SGA gene in S. diastaticus YIY345. In order to compare the biochemical properties of the extracellular glucoamylase and the SGA, the SGA was purified from the culture supernatant through ammonium sulfate precipitation, DEAE-Sephadex A-50, CM-Sephadex C-50 and Sephadex G-200 chromatography. The molecular weight of the intact SGA was estimated to be about 130 kDa by gel filtration chromatography with high performance liquid chromatography (HPLC) column. Sodium dedecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed it was composed of two heterogeneous subunits, 63 kDa and 68 kDa. The deglycosylation of the SGA generated a new 59 kDa band on the SDS-PAGE analysis, indicating that two subunits are glycosylated but the extent of glycosylation is different between them. The optimum pH and temperature of the SGA were 5.5 and $45^{\circ}C$, respectively, whereas those for the extracellular glucoamylase were 5.0 and $50^{\circ}C$. The SGA were more sensitive to heat and SDS than the extracellular glucoamylase.