• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.485-493
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• 2013

PURPOSE. To evaluate the effects of surface treatments on shear bond strength (SBS) between microwave and conventionally sintered zirconia core/veneers. MATERIALS AND METHODS. 96 disc shaped Noritake Alliance zirconia specimens were fabricated using YenaDent CAM unit and were divided in 2 groups with respect to microwave or conventional methods (n=48/group). Surface roughness (Ra) evaluation was made with a profilometer on randomly selected microwave (n=10) and conventionally sintered (n=10) cores. Specimens were then assessed into 4 subgroups according to surface treatments applied (n=12/group). Groups for microwave (M) and conventionally (C) sintered core specimens were as follows; $M_C$,$C_C$: untreated (control group), $M_1,C_1:Al_2O_3$ sandblasting, $M_2,C_2$:liner, $M_3,C_3:Al_2O_3$ sandblasting followed by liner. Veneer ceramic was fired on zirconia cores and specimens were thermocycled (6000 cycles between $5^{\circ}-55^{\circ}C$). All specimens were subjected to SBS test using a universal testing machine at 0.5 mm/min, failure were evaluated under an optical microscope. Data were statistically analyzed using Shapiro Wilk, Levene, Post-hoc Tukey HSD and Student's t tests, Two-Way-Variance- Analysis and One-Way-Variance-Analysis (${\alpha}$=.05). RESULTS. Conventionally sintered specimens ($1.06{\pm}0.32{\mu}m$) showed rougher surfaces compared to microwave sintered ones ($0.76{\pm}0.32{\mu}m$)(P=.046), however, no correlation was found between SBS and surface roughness (r=-0.109, P=.658). The statistical comparison of the shear bond strengths of $C_3$ and $C_1$ group (P=.015); $C_C$ and $M_C$ group (P=.004) and $C_3$ and $M_3$ group presented statistically higher (P=.005) values. While adhesive failure was not seen in any of the groups, cohesive and combined patterns were seen in all groups. CONCLUSION. Based on the results of this in-vitro study, $Al_2O_{3-}$ sandblasting followed by liner application on conventionally sintered zirconia cores may be preferred to enhance bond strength.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.41-47
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• 2009

This study investigated antioxidative and hypoglycemic activities of Omija for evaluation of usefulness as a functional food resource. Omija water extracts were extracted with water for 24 hr, 6 hr and 3 hr at room temperature, 60$^{\circ}C$ and 100$^{\circ}C$, respectively. Omija ethanol extracts were extracted with 60% ethanol for 24 hr and 3 hr at room temp temperature and 60$^{\circ}C$, respectively. The antioxidant properties of Omija(Schizandra chinensis Baillon) extracts prepared under different extraction conditions were evaluated by a variety of radical scavenging assays including DPPH, $ABTS^{{cdot}+}$, and nitrite and reducing power. Hypoglycemic activity was examined for $\alpha$-glucosidase inhibition using an in vitro model. The total phenolic content was also determined. Antioxidant activities of Omija were the highest in the group extracted with 60% ethanol for 3 hr. The ethanol extracts showed higher activity than water extracts. An extraction temperature was the highest in 60$^{\circ}C$. The total phenolic content extracted with 60% ethanol for 3 hr at 60$^{\circ}C$ was 530 mg GAE/100 g. The water extract extracted with water for 24 hr at room temperature showed the lowest antioxidant activity and phenolic content. $\alpha$-glucosidase inhibitory activity was the highest in the group extracted with 60% ethanol for 3 hr at 60$^{\circ}C$, followed by the group extracted with 60% ethanol for 24 hr. The results suggest that extraction of Omija by 60% ethanol for 3 hr at 60$^{\circ}C$ will be useful as a functional food resource with natural antioxidants and hypoglycemic activities.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.83-89
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• 2012

In this study red ginseng was extracted with ethanol and then fermented by yeasts including Lactobacillus casei and Bifidobacterium longum. Fermented red ginseng extracts(FRGE) were found to be more effective antioxidants in vitro with regards to 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical scavenging activity than red ginseng extracts(RGE). In FRGE, the contents of ginsenosides $Rb_1$, $-Rb_2$ and -Rc were much lower than in RGE, however, the contents of ginsenosides 20(S)$-Rg_3$, 20(R)$-Rg_3$ and compound K were higher than RGE. FRGE was added to Yanggaeng(0, 5, 10, 15, 20%), and physicochemical and sensory evaluations of the Yanggaeng were conducted. The L and b values of Yanggaeng with added FRGE were decreased by increasing the ratio of FRGE, while the a value was increased. Sensory evaluations for, taste, color, flavor, texture and overall acceptability of Yanggaeng with addition of FRGE (10%) were applicable for improving the Yanggaeng product.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.227-234
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• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.4
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• pp.211-217
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• 2006

Purpose: Recombinant ScFv lym-1 was produced, using pET vector system for large scale production. Methods: ScFv lym-1 gene inserted pET-22b (+) vector, was expressed in E.coli BL-21 strain. ScFv lym-1 antibody extracted from periplasm, was purified with His-Taq column. To evaluated immunoreactivity with Raji cell, ScFv lym-1 was labeled with I-125 and I-125 ScFv lym-1 was purified with desalting column. Raji cell was injected into the C57BR/cdJ SCID mice. Gamma camera imaging were taken time point at 1, 8, 24, and 48 hr with 8 mm pinhole collimator. Results: An active scFv lym-1 could be produced in E. coli with soluble iron using PET vector system. Immuuoreaetivity and affinity constant of IgG lym-1 were 54% and $1.83{\times}10^9M^{-1}$, respectively, and those of scFv lym-1 were 53.7% and $1.46{\times}10^9M^{-1}$, respectively. Biodistribution of I-125 scFv lym-1 antibody showed faster clearance in blood, spleen, kidney and than I-125 IgG lym-1 antibody. Gamma camera image of I-125 scFv lym-1 antibody showed faster clearance and tumor targeting liver than I-125 IgG lym-1 antibody. Conclusions: In vitro properties of scFv lym-1 were similar to those of IgG lym-1. ScFv lym-1 showed faster blood clearance than IgG lym-1 There results suggest that scFv lym-1 antibody can be useful for tumor imaging agent.

• Food Science and Preservation
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• v.19 no.5
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• pp.751-756
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• 2012

Antioxidant capacity and acetylcholinesterase (AChE) inhibitory activity of the aqueous methanolic extract of Rhus javanica were investigated in vitro. The antioxidant properties was measured by radical scavenging assays using DPPH and $ABTS^+$ radicals. The AChE inhibitory efficacy of R. javanica was tested by Ellman's assay and the total phenolic content was determined using a spectrophotometric method. All tested samples showed a dose-dependent AChE inhibitory and radical scavenging activities. In particularly, ethyl acetate (EtOAc)-soluble portion from the methanolic extract of R. javanica showed significantly higher inhibitory activity than other organic solvent soluble-portions in an AChE and radical scavenging assay systems. These results suggest that R. javanica may be possess potential benefits which might be useful in development of antioxidant and anti-alzheimer's disease ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.993-999
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• 2015

For the purpose of investigating the in vitro antidiabetic activity of a medicinal herb and herb mixture extracts prepared through traditional antidiabetic prescription, this study examined ${\alpha}$-glucosidase inhibitory activity. Tyrosinase, a type I membrane glycoprotein, is synthesized and glycosylated in the endoplasmic reticulum (ER) and Golgi. The enzyme is subsequently transported to melanosomes, where it participates in melanogenesis. Previous studies showed that disruption of early ER N-glycan processing by an ${\alpha}$-glucosidase inhibitor suppresses tyrosinase enzymatic activity and melanogenesis. According to the results, most oriental medicinal herbal extracts were stronger than acarbose and N-butyldeoxynojirimycin, known as an ${\alpha}$-glucosidase inhibitor. Interestingly, ethyl acetate layer of enzyme hydrolyzed Cheongsimyeonjaeum had an inhibitory effect on melanin synthesis in B16F1 cells, although it did not inhibit tyrosinase activity directly. Together, ${\alpha}$-glucosidase inhibition activity could be used to evaluate anti-melanogenesis, although cross-checking with melanin inhibitory assay is recommended.

• Journal of Life Science
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• v.25 no.4
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• pp.425-432
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• 2015

This study was performed to develop high-value-added biomaterials for health and beauty products. Extracts of ethanol and hot water and their subsequent organic solvent fractions were prepared from Lees of Wookukseng (LW), a commercialized Korean traditional rice wine. We investigated their activities on blood coagulation, platelet aggregation, hemolysis against human red blood cells (hRBCs), and anti-oxidation. The water content, pH and brix of the LW were 80.3%, 3.94 and 13.0°, respectively. The yield of ethanol extraction (6.62%) was 3.15 times higher than that of hot-water extraction (2.1%), and the ethyacetate fraction (EAF) of ethanol extract showed the highest content of total polyphenol (128 mg/g) among the various fractions. In anticoagulation activity assay, the EAF of ethanol extract showed a 15-fold extension in TT, PT, and aPTT, indicating that the EAFs contain various inhibitory substances against thrombin, prothrombin and coagulation factors. In anti-platelet aggregation activity assay, the butanol fraction and water residue of ethanol extract showed significant inhibition activity. The activities were comparable to aspirin, a commercial anti-thrombosis agent. The above extracts and fractions did not show hemolysis activity against hRBC up to 5 mg/ml, and had radical scavenging activity against DPPH anion, ABTS cation and nitrite. Our results suggest that the active fractions prepared from LW, which has no specific usage until now, have a high potential as novel resources for anti-thrombosis agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.820-825
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• 2010

The functional food components from various Basidiomycota were investigated to improve human intestinal microflora, especially associated with obesity. EtOH extract from Gyrophora esculenta fruit body and Coriolus versicolor judae mycelia showed antimicrobial activities on Eubacterium limosum, Clostridium perfrigens, Clostridium paraputrificum, Clostridium difficile and Clostridium ramosum, and on Bacteroides fragilis, respectively. Although the 80% EtOH extract from G. esculenta fruit body and hot-water extract from C. versicolor judae mycelia did not reduce weight of the rats in the high fat diet, these extracts showed stability at high temperatures and at wide pH ranges. In the rat group of feeding 80% EtOH extract from G. esculanta fruit body, Bifidobacterium spp. were increased and Clostridium spp. and Eubacterium spp. were decreased compared to the high fat feeding group. Also sensory evaluation was carried out for the development of prototype drink product. These results demonstrated the possibilities of C. versicolor judae and G. esculenta as a functional food components to control intestinal microbial flora.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.31-38
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• 2006

This experiment was carried out to determine the effects of different sowing dates and cultivars on the forage yield and quality of winter rye (Secale cereale L.). The experiment was conducted in a split plot design with three replications. The main plots consisted of two sowing dates such as early (15 September) and late (30 September). The subplots consisted of rye cultivars of five different maturity groups such as 'Kodiak' (Late), 'Koolgrazer' (Early), 'Danko' (Late), 'Homil22' (Medium) and 'Olhomi1' (Early). Dry matter (DM) content at early sowing (19.7%) was higher than those at late sowing (17.8%), while crude protein (CP) and total digestible nutrients (TDN) contents at early sowing (16.6% and 61.6%) were lower than those at late sowing (16.8% and 63.1%). Although DM content of early maturing cultivars (Koolgrazer and Olhomi1) was higher than the other cultivars, CP and TDN contents of those were lower compared to other cultivars. The contents of fiber components (ADF, NDF and cellulose) at early sowing were higher than those at late sowing, while ADL and hemicellulose at early sowing were lower than those at late sowing. ADF and cellulose of early maturing cultivars were higher than those of the other cultivars, while ADL and hemicellulose of Danko were higher than that of the other cultivars. DM, CP, In vitro dry matter digestibility (IVDMD) and TDN yields at early sowing were higher than those at late sowing, and early maturing cultivars were higher than those of the other cultivars. Results of this study indicate that forage production technology in combination with early sowing and use of early maturing rye cultivar could enhance both production and quality of rye.