• Korean Journal of Materials Research
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• v.22 no.8
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• pp.433-438
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• 2012

A chemical process involves polymerization within microspheres, whereas a physical process involves the dispersion of polymer in a nonsolvent. Nano-sized monodisperse microspheres are usually prepared by chemical processes such as water-based emulsions, seed suspension polymerization, nonaqueous dispersion polymerization, and precipitation polymerizations. Polymerization was performed in a four-necked, separate-type flask equipped with a stirrer, a condenser, a nitrogen inlet, and a rubber stopper for adding the initiator with a syringe. Nitrogen was bubbled through the mixture of reagents for 1 hr. before elevating the temperature. Functional silane (3-mercaptopropyl)trimethoxysilane (MPTMS) was used for the modification of silica nanoparticles and the self-assembled monolayers obtained were characterized by X-ray photoelectron spectroscopy (XPS), laser scattering system (LSS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), elemental analysis (EA), and thermogravimetric analysis (TGA). In addition, polymer microspheres were polymerized by radical polymerization of ${\gamma}$-mercaptopropyl modified silica nanoparticles (MPSN) and acrylamide monomer via precipitation polymerization; then, their characteristics were investigated. From the elemental analysis results, it can be concluded that the conversion rate of acrylamide monomer was 93% and that polyacrylamide grafted to MPSN nanospheres via the radical precipitation polymerization with AAm in ethanol solvent. The microspheres were successfully polymerized by the 'graft from' method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3269-3273
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• 2009

In this study, recycling methods of nano $TiO_2$-coated silica-bead were conducted in order to solve a deactivation problem of bead that had been invented for decomposition of pollutants in aqueous solution. Surface cleansing was selected as the recycling method for used beads. The surface cleansing was done with four different solutions such as distilled water, surfactant, acetone, and ethyl alcohol(ethanol). The recycling process consists of cleansing and calcination. After cleaning the used (deactivated) beads, calcination was done at $100^{\circ}C$, $200^{\circ}C$ and $300^{\circ}C$ for 30 minutes, respectively. This process was repeated three times. The activity of the recycled bead was measured by photo-degradation of methylene blue. The result shows that acetone cleansing and calcination at $100^{\circ}C$ for 30 minutes was the most efficient recycling method.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.19-43
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• 1997

The barrier membranes for GTR procedure could be affected bY bacterial contamination after exposure to oral environment. This study was done to evaluate whether the tetracycline impregnated barrier membranes could inhibit bacterial attachment and penetration into membranes. The resorbable membrane(polylactic and polyglycolide copolymer, $Resolute^{(R)}$, W.L Gore and Associates, Inc..USA) and the non-resorbable membrane(e-PTFE; Gore-TexTM, W.L. Gore & Associates, Inc.,USA) were cut into 4mm discs and trated with 5% tridodecylmethylammonium chloride solution in ethanol and dried in air. The membranes were immersed in tetracycline(TC) solution (100mg/ml, pH 8.0) and dried. To the maxillary canine-premolar region in six periodontally healthy volunteers, removable acrylic devices were inserted, on which 8 cylindrical chambers were glued with TC impregnated and non-impregnated discs, the membrane discs were examined for bacterial attachment and penetration, and structural changes under SEM and LM. From the 1st day to the 7th day, membranes showed bacterial plaque formation composed of cocci and rods. Thereafter, filamentous bacteria appeared and the plaque thickness increased. The TC impregnated e-PTFE membranes showed less bacterial attachment and delayed in bacterial plaque maturation than non-treated membranes. As for bacterial penetration, the TC impregnated e-PTFE membranes showed superficial invasion and infrequent presence of bacteria in unexposed inner surface at the 4th week. while the non-treated e-PTFE membranes showed deep bacterial invasion at the 2nd week and frequent presence of internal bacteria at the 4th week. The resorbable membranes started to be resorbed at the 2nd week and were perforated at the 4th week, regardless of TC treatment. In conclusion, bacterial plaque formation and penetration was efficiently delayed in TC impregnated e-PTFE membranes, whereas resorbable membranes were similar in bacterial invasion due to membrane degradation and perforation, regardless of TC treatment.

• Korean journal of food and cookery science
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• v.33 no.1
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• pp.113-120
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• 2017

Purpose: Lipid autoxidation of a soybean oil-in-water emulsion with high oil content was studied under after basil extract and/or iron addition. Methods: The emulsion consisted of tocopherol-stripped soybean oil (40 g), citrate buffer (60 g, pH 4.0), and/or $FeSO_4$ (0.5 mg) with 75% ethanol extract (200 mg/kg) of basil (Ocimum basilicum). Lipid oxidation was evaluated using headspace oxygen content, hydroperoxide contents, and p-anisidne values of the emulsion. Polyphenol compound retention in the emulsion during oxidation was determined spectrophotometrically. Results: Addition of basil extract significantly (p<0.05) decreased reduced hydroperoxide contents of the emulsion, and iron significantly (p<0.05) increased anisidine values and decreased oxygen contents. Co-addition of basil extract and iron showed significantly (p<0.05) lower reduced hydroperoxide contents in the emulsion than compared to those of the emulsion with added iron and the control emulsion without basil extract nor or iron. During the emulsion oxidation, polyphenol compounds in the emulsion with added basil extract were degraded, but more slowlywhich was slowed degraded in the presence of iron. Conclusion: The iIron increased the lipid oxidation through hydroperoxide decomposition, and basil extract showed antioxidant activity through radical-scavenging and iron-chelation. Polyphenol degradation was decelerated by iron addition, which suggested suggests iron chelation may be more preferred topreferentially activated over radical scavenging in the antioxidant action by of basil extract in the oil-in-water emulsion with high oil content.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1282-1292
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• 2018

The exopolysaccharide (EPS) produced by Bacillus amyloliquefaciens GSBa-1 was isolated and purified by ethanol precipitation, and DEAE-cellulose and Sepharose CL-6B chromatographies. The molecular mass of the purified EPS was determined to be 54 kDa. Monosaccharide analysis showed that the EPS was composed of predominantly glucose, and it was further confirmed by NMR spectroscopy to be ${\alpha}-glucan$ that consisted of a trisaccharide repeating unit with possible presence of two ${\alpha}-(1{\rightarrow}3)$ and one ${\alpha}-(1{\rightarrow}6)$ glucosidic linkages. Microstructural analysis showed that the EPS appeared as ellipsoid or globose with a smooth surface. The EPS had a degradation temperature at $240^{\circ}C$. Furthermore, the EPS had strong DPPH and hydroxyl radical scavenging activities, and moderate superoxidant anion scavenging and metal ion-chelating activities. This is the first characterization of a glucan produced by B. amyloliquefaciens with strong antioxidant activity. The results of this study suggest the potential of the EPS from B. amyloliquefaciens GSBa-1 to serve as a natural antioxidant for application in functional products.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.68-68
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• 2018

In this study, we investigated whether S. baicalensis rhizome ethanol extract (SBRE) has antioxidant capacities against oxidative stress induced cellular damage in the HaCaT keratinocytes. Our results revealed that treatment with SBRE prior to hydrogen peroxide ($H_2O_2$) exposure significantly increased the HaCaT cell viability. SBRE also effectively attenuated $H_2O_2$ induced comet tail formation, and inhibited the $H_2O_2$ induced phosphorylation levels of the histone ${\gamma}H2AX$, as well as the number of apoptotic bodies and Annexin V positive cells. In addition, SBRE exhibited scavenging activity against intracellular ROS generation and restored the mitochondria membrane potential loss induced by $H_2O_2$. Moreover, $H_2O_2$ enhanced the cleavage of caspase-3 and degradation of poly (ADP-ribose)-polymerase as well as DNA fragmentation; however, these events were almost totally reversed by pretreatment with SBRE. Furthermore, SBRE increased the levels of HO-1 associated with the induction of Nrf2. Therefore, we believed that SBRE may potentially serve as an agent for the treatment and prevention of neurodegenerative diseases caused by oxidative stress.

• Journal of Sericultural and Entomological Science
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• v.46 no.1
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• pp.28-31
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• 2004

Bombyx mori silk fibroin/hyaluronic acid blend films were prepared by mixing aqueous solution of B. mori silk fibroin and hyaluronic acid. According to the FTIR spectra, no interaction between silk fibroin and hyaluronic acid was found. The conformation of silk fibroin in blend films was changed from random coil to $\beta$-sheet structure by treatment of EDC ethanol solution. Thermal degradation peak of silk fibroin and hyaluronic acid was also not altered by blending each other. The average swelling ratio of silk fibroin/hyaluronic acid blend films was 70. Therefore, silk fibroin/hyaluronic acid blend films might be one of possible wound dressing materials.

• Journal of Ginseng Research
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• v.39 no.1
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• pp.54-60
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• 2015

Background: The present study was designed to prepare and find the optimum active preparation or fraction from Korea Red Ginseng inhibiting matrix metalloproteinase-13 (MMP-13) expression, because MMP-13 is a pivotal enzyme to degrade the collagen matrix of the joint cartilage. Methods: From total red ginseng ethanol extract, n-BuOH fraction (total ginsenoside-enriched fraction), ginsenoside diol-type-enriched fraction (GDF), and ginsenoside triol-type-enriched fraction (GTF) were prepared, and ginsenoside diol type-/F4-enriched fraction (GDF/F4) was obtained from Panax ginseng leaf extract. Results: The n-BuOH fraction, GDF, and GDF/F4 clearly inhibited MMP-13 expression compared to interleukin-$1{\beta}$-treated SW1353 cells (human chondrosarcoma), whereas the total extract and ginsenoside diol-type-enriched fraction did not. In particular, GDF/F4, the most effective inhibitor, blocked the activation of p38 mitogen-activated protein kinase (p38 MAPK), c-Jun-activated protein kinase (JNK), and signal transducer and activator of transcription-1/2 (STAT-1/2) among the signal transcription pathways involved. Further, GDF/F4 also inhibited the glycosaminoglycan release from interleukin-$1{\alpha}$-treated rabbit cartilage culture (30.6% inhibition at $30{\mu}g/mL$). Conclusion: Some preparations from Korean Red Ginseng and ginseng leaves, particularly GDF/F4, may possess the protective activity against cartilage degradation in joint disorders, and may have potential as new therapeutic agents.

• Food Engineering Progress
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• v.21 no.3
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• pp.286-291
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• 2017

This study was conducted to certify the effect of aqueous extracts from fifty medicinal plants on the activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in vitro. Each aqueous extract was prepared by combining one-part medicinal plants with twenty-parts distilled water at $80^{\circ}C$ for 8 h. Among the fifty medicinal plants, Allium sativum L. and Cinnamomum cassia Presl were regarded as an effective anti-hangover substance. Allium sativum L. extract increased ALDH activity more than 2 times compared with ADH activity, enhancing the acetaldehyde degradation. Cinnamomum cassia Presl extract dramatically inhibited ADH activity compared with ALDH activity, thus potently decreasing the acetaldehyde formation. ADH and ALDH activities were proportionally inhibited according to the increased concentration of Cinnamomum cassia Presl extract. The aqueous extract of Cinnamomum cassia Presl at a concentration of $45.33{\mu}g/mL$ inhibited ADH activity by 52.8% and ALDH activity by 11.0%.

• Korean Journal of Pharmacognosy
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• v.49 no.4
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• pp.305-311
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• 2018

Osteoarthritis (OA) is the most common form of joint disease, characterized by articular cartilage, osteonecrosis, and osteochondral bone erosion. It is an early, progressive disease that combines joint stiffness and joint pain and reduces cartilage function and condition. Interleukin-1 beta ($IL-1{\beta}$) is thought to be important to the pathogenesis of OA and significantly increases the expression of matrix metalloproteinases (MMPs), which play an important role in cartilage degradation in OA. Sparassis crispa (Wulf.) is an edible / medicinal mushroom that has been reported to variety of biological activities. In this study, investigated the Anti-inflammatory effect of Sparassis crispa (Wulf.) ethanol extract (SCE) on $IL-1{\beta}$ stimulated SW1353 chondrocytes. SCE decreased the expression and activity of MMPs by $IL-1{\beta}$ and decreased the levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) associated with the inhibition of prostaglandin E2($PGE_2$) in $IL-1{\beta}$ stimulated SW-1353 chondrocytes. In addition, SCE inhibits the expression of MAPK (mitogen-activated protein kinase) and $NF-{\kappa}B$ (nuclear factor-kappa B) signaling in $IL-1{\beta}$ stimulated SW-1353 cells, and SCE inhibits the production of reactive oxygen species (ROS) through heme oxygenase-1 (HO-1) expression. Thus, it is suggested that SCE has a potential as an anti-inflammatory agent in osteoarthritis treatments.