• Polymer(Korea)
• /
• v.30 no.1
• /
• pp.14-21
• /
• 2006

Tissue engineering techniques require the use of a porous biodegradable/bioresorbable scaffold, which server as a three-dimensional template for initial cell attachment and subsequent tissue formation in both in vitro and in vivo. Small intestinal submucosa (SIS) has been investigated as a source of collagenous tissue with the potential to be used as biomaterials because of its inherent strength and biocompatibility. SIS-loaded poly(L-lactide-co-glicolide)(PLGA) scaffolds were prepared by solvent casting/particle leaching. Characterizations of SIS/PLGA scaffold were carried out by SEM, mercury porosimeter, and so on. Muscle-derived stem cells can be differentiated in culture into osteoblasts, chondrocytes, and even myoblasts by the controlling the culture environment. Cellular viability and proliferation were assayed by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium-bromide(MTT) test. Osteogenic differential cells were analyzed by alkaline phosphatase(ALP) activity. SIS/PLGA scaffolds were implanted into the back of athymic nude mouse to observe the effect of SIS on the osteoinduction compared with controlled PLGA scaffolds. Thin sections were cut from paraffin embedded tissues and histological sections were conducted hematoxylin and eosin (H&E), Trichrome, and von Kossa. We observed that bone formatioin of SIS/PLGA hybrid scaffold as natural/synthetic scaffold was better thean that of only PLGA scaffold. It canb be explained that SIS contains various kinds of bioactive molecules for osteoinduction.

• Polymer(Korea)
• /
• v.27 no.5
• /
• pp.397-404
• /
• 2003

The interaction of cell adhesive protein and polypeptide with bone marrow stromal stem cells (BMSCs) grown in tissue engineered films and scaffolds were examined. Several proteins or polypeptide known as cell-adhesive were coated adsorption on poly(lactide-co-glycolide) (PLGA) films and scaffolds and adhesion and proliferation behavior of BMSC on those surfaces were compared. The protein and polypeptide used include collagen IV, fibrinogen, laminin, gelatin, fibronectin, and poly(L-lysine). The protein and polypeptide were adsorbed on the PLGA film surfaces with almost monolayer coverage except poly(L-lysine). BMSCs were cultured for 1, 2, and 4 days on the protein- or polypeptide-adsorbed PLGA films and scaffolds. The cell adhesion and proliferation behaviors were assessed by sulforho damine B assay. It was observed that the protein- or polypeptide-adsorbed surfaces showed better cell adhesion and proliferation than the control.

• Korean Journal of Microbiology
• /
• v.45 no.1
• /
• pp.63-68
• /
• 2009

The exo-polysaccharide producing microorganism, Aureobasidium pullulans IMS-822, was isolated and identified from soil. The viscosity-average molecular weight of exo-polysaccharide was calculated as $8.9{\times}10^5$ by Mark-Houwink equation. The sugar component of exo-polysaccharide was determined as glucose by HPLC analysis. The IR spectra indicated that the exo-polysaccharide has an absorption peak at 890 $cm^{-1}$ for the ${\beta}-configuration$ of D-glucan. The $^{13}C$ NMR signal at ${\delta}$ 86.62 ppm arose from the substituted C-3 of glucose. The signal at ${\delta}$ 72.11 ppm was assigned to C-6 of branched ${\beta}-(1{\to}3)-D-glucosyl$ residues. Viscosity and Congo red reaction indicated that {\beta}-(1{\to}3)(1{\to}6)-glucan$ produced by A. pullulans IMS-822 has a highly ordered hydrogen-bond dependent conformation in aqueous solution, which collapses in strong alkaline solution.

• Journal of Embryo Transfer
• /
• v.13 no.3
• /
• pp.235-243
• /
• 1998

In this study, we investigated the effects of three kinds of culture medium (Charles and Rosenkrans; CRlaa, Tyrode's; TALP, synthetic oviduct fluid: SOF), insulin transferrin + selenium complex (ITS), macromolecules(polyvinyl alcohol: PVA, fetalb-ovine serum: FBS) and NaCl on the development of early bovine embryos. In experiment 1, there were no differences in embryo development among three kinds of embryo culture medium (CR $l_{aa}$ , TALP, SOF). In experiment 2, BSA, FBS and PVA were added each in TALP as macromolecule sources. The developmental rates of embryos in BSA or FBS added TALP were significantly higher than in PVA added one (p〈0.01), but there was no difference between BSA and FBS added groups. In experiment 3, bovine embryos were cultured in TALP with the following supplements: BSA alone(1, 3 or 8 mg/ml, each) or BSA(1, 3 or 8 mg/ml, each)+ITS (10$\mu\textrm{g}$/m1 insulin, 5 $\mu\textrm{g}$/ml transferrin, 5 ng/ml selenium). In higher concentration of BSA and ITS supplemented groups, the developmental rates over compacted morula were higher than others, but there was a significant effect of ITS only in 1 mg/ml of BSA added group (p〈0.05). In experiment 4, the effect of reduced concentration of NaCl was evaluated. The developmental rate over compacted morula in the medium containing 90 mM of NaCl was higher than in 114 mM group (p〈0.05). In conclusion, BSA could be used as a macromolecule source in bovine embryo culture, and ITS, as a serum substitute, could be used for improving of embryonic development. Also, reduction of NaCl concentration from 114 mM to 90 mM may improve the development of bovine embryos.bryos.

• Korean Journal of Food Science and Technology
• /
• v.13 no.2
• /
• pp.107-113
• /
• 1981

Free sugars were isolated from ginseng root and its products and analyzed by using high performance liquid chromatogrphy. To isolate free sugars from aqueous sample solution fat-soluble components, crude saponin and protein were removed from the solution by extracting with benzene, water-saturated butanol and 80% ethanol, respectively. Free sugars found from both ginseng root and its products were fructose, glucose, sucrose and maltose, and the only sugar detected from red ginseng root and its products was rhamnose. Major sugar detected from fresh ginseng and white ginseng roots was sucrose, while sucrose and maltose were major sugars of red ginseng root.

• Applied Chemistry for Engineering
• /
• v.17 no.5
• /
• pp.521-526
• /
• 2006

A membrane bioreactor (MBR) is an effective tool for wastewater treatment with recycling. MBR process has several advantages over conventional activated sludge process (ASP); reliability, compactness, and quality of treated water. The resulting high-quality and disinfected effluents suggest that MBR process can be suitable for the reused and recycling of wastewater. An anoxic/oxic (A/O) type MBR was applied to simultaneous removal of organics and nutrients in sewage. At first, the efficiency of submerged MBR process was investigated using a hollow fiber microfiltration membrane with a constant flux of $10.2L/m^2{\cdot}h$ at each solids retention time (SRT). Results showed that protein/carbohydrate (P/C) ratio increased and total extracellular polymeric substances (EPS) remained constant with SRT increased. Secondly, A/O type MBR with a reverse osmosis (RO) membrane was employed to treat the municipal wastewater. The performance of A/O type MBR-RO process is better for the treatment of organics and nutrients than ASP-MF-RO process in terms of consistent effluents quality.

• Polymer(Korea)
• /
• v.26 no.4
• /
• pp.523-534
• /
• 2002

A new hydroxypropylcellulose (HPC) capable of exhibiting reflection colours in the temperature ranges of about 60-$130^{\circ}C$ and acrylic acid esters of HPC (ESs) with degree of esterification (DE) ranging from 1 to 3 were synthesized. The crosslinked ES films with the optical pitch ($\lambda_m$) ranging throughout the visible region were also prepared by exposing thermotropic cholesteric phases of ESs with a DE of more than 2 to UV light at $50^{\circ}C$. The thermal and optical properties for both the uncrosslinked and crosslinked samples and the swelling behavior of the crosslinked films in acetone were investigated. The $\lambda_m$'s of ESs, as well as HPC itself, increased with temperature. However, the $\lambda_m$'s of ESs were larger than of HPC at the same temperature and decreased with increasing DE. The temperature dependence of $\lambda_m$of the crosslinked samples was much weaker than that of ESs. Moreover, in contrast with ESs that exhibit a decrease of the isotropization temperature with increase in the DE, the networks were found to decompose at about $210^{\circ}C$, giving no transition to an isotropic state. The crosslinked samples exhibited an anisotropic swelling, suggesting that the two-dimensional crosslinking preferentially performs between ES molecules.

• Polymer(Korea)
• /
• v.28 no.6
• /
• pp.478-486
• /
• 2004

Small intestinal submucosa (SIS) is consisted with collagen and glycosaminoglycan as well as some growth factors which can stimulate cell activity. Recently, it has been recognized that SIS has been successfully examined in the bio-medical application as biomaterials without xenograft immune-rejection response. We prepared native SIS sheets and acid treated SIS sheets by acetic acid with 1 or 5-layered sheets, respectively. The water uptake ability of native and acid treated SIS sheets was examined to evaluate the possibility as wound dressings. Morphologies of SIS sheets were characterized by SEM and the effects of various buffer solutions and different pH solutions on the water uptake ability were observed for 16 days. We observed that the acid treated SIS sheets had higher water uptake ability than native SIS sheets. Also, the water uptake ability of these was slightly higher in various buffers than distilled water. In conclusion, this study suggests that native and acid treated SIS sheets could be useful for the applications of wound dressing and biodegradable injectable materials.

• Clean Technology
• /
• v.8 no.2
• /
• pp.85-92
• /
• 2002

Red mud is generated as a by-product during the production of aluminum hydroxide from bauxite ore. In this study the red mud coagulants were prepared by reacting 100 ml of 5 M $H_2SO_4$ solution with 10g of red mud at $85^{\circ}C$ or by reacting 100ml of 9M HCl solution with 10g of red mud at $25^{\circ}C$. The prepared red mud coagulants were tested for their coagulation performance of pollutants in the municipal and industrial wastewater. In addition, the coagulation performance was compared with that of a commercially available coagulant ($FeCl_3$). As a result, the red mud coagulants were found to have a good removal efficiency of pollutants in the municipal wastewater (turbidity, phosphate phosphorus) and in the plating wastewater (turbidity, $Pb^{2+}$, $Cd^{2+}$, $Cu^{2+}$, $Zn^{2+}$, $Cr^{3+}$). In the experiment to remove COD in the petrochemical wastewater, the COD removal efficiency by the red mud coagulants was a little poor, but it was better than that by $FeCl_3$.

• Polymer(Korea)
• /
• v.32 no.1
• /
• pp.49-55
• /
• 2008

It is recognized that Schwann cells (SC) are essential for peripheral nerve development and regeneration. SIS (small intestinal submucosa) consists of some growth factors which can stimulate cell activity without immune rejection responges. SCs were harvested from the femurs and tibias of female Fischer rat and then suspended with $2{\times}10^6$ cell/sponge in SIS sponge. Fischer rat received an implant consisting of the SCs and the SIS sponge at the place of a 5 mm gap created by the sciatic nerve resection. Thin sections were stained with H &E staining and immunostaining of S-100, GFAP and NF after 1, 2, and 4 weeks. It was observed that the effects of the SIS sponge with SCs on neuroinduction(Group II, with scaffold & cell) are strong as much as uninjured model(Control I), and significantly stronger than SIS sponge model (Group 1, with scaffold only) and blank model (Control II). In conclusion, these results suggest that SIS sponge filled with SCs may have an important role for peripheral nerve regeneration of tissue engineering.