• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.415-420
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• 2014

Toxoplasmosis is an important cause of foodborne, inflammatory illnesses, as well as congenital abnormalities. Currently available therapies are ineffective for persistent chronic disease and congenital toxoplasmosis or have severe side effects which may result in life-threatening complications. There is an urgent need for safe and effective therapies to eliminate or treat this cosmopolitan infectious disease. The aim of this study was to investigate the in vitro anti-Toxoplasma activities of Suaeda maritime, one of the halophytes, using tachyzoit of T. gondii RH strain infected HeLa cells. As the results, the selectivity of Suaeda maritime extract was 6.63, which was higher than Sulfadiazine selectivity (2.06). Also, we perfomed the cell proliferation inhibition test and the morphological study to evaluate the anti-T. gondii activity of Suaeda maritime extract with HeLa cells. As the results, the inhibition rate of the Suaeda maritime extract was high inhibition rate. This indicates that the Suaeda maritime extract may be used for new anti-T. gondii agent.

• Polymer(Korea)
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• v.39 no.2
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• pp.317-322
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• 2015

Salinity gradient power is a system which sustainably generates electricity for 24 hrs, if the system is constructed at a certain place where both seawater and river water are consistently pumped. Since power is critically determined by the water flux and the salt rejection, a membrane of water-semipermeable aquaporin protein in cell membranes was studied for pressure-retarded osmosis. NaCl was used as a salt, and $NaNO_3$ was used as a candidate to check the ion selectivity. The water flux of biomimetic aquaporin membranes was negligible at a concentration below 2M. Also, there is no remarkable dependence of water flux and ion selectivity on concentrations higher than 3M. Therefore, the biomimetic aquaporin membrane could not be applied into pressure-retarded osmosis; however, if a membrane could overcome the current limitations, the properties shown by natural cells could be accomplished.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.26-31
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• 2016

Toxoplasmosis is an important cause of foodborne, inflammatory illnesses, as well as congenital abnormalities. Currently available therapies are ineffective for persistent chronic disease and congenital toxoplasmosis or have severe side effects which may result in life-threatening complications. There is an urgent need for safe and effective therapies to eliminate or treat this cosmopolitan infectious disease. The aim of this study was to investigate the in vitro anti-Toxoplasma activities of Plantago asiatica L., one of the herbal extracts, using tachyzoit of T. gondii RH strain infected HeLa cells. As the results, the selectivity of Plantago asiatica L. extract was 4.5, which was higher than Sulfadiazine selectivity (0.4). Also, we perfomed the cell proliferation inhibition test and the morphological study to evaluate the anti-T. gondii activity of Plantago asiatica L. extract with HeLa cells. As the results, the inhibition rate of the Plantago asiatica L. extract was high inhibition rate. This indicates that the Plantago asiatica L. extract may be used for new anti-T. gondii agent.

• Journal of Life Science
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• v.17 no.11
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• pp.1517-1522
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• 2007

Gap junction channels formed by two adjacent cells allow the passage of small molecules up to ${\sim}\;1\;kDa$ between them. Hemichannel (connexon or half of gap junction) also behaves as a membrane channel like sodium or potassium channels in a single cell membrane. Among 26 types of connexin (Cx), $Cx32^*43E1$ (a chimera in which the first extracellular loop of Cx32 has been replaced with that of Cx43), Cx38, Cx46, and Cx50 form functional hemichannels as well as gap junction channels. Although it is known that Xenopus oocytes express endogenous connexin 38 (Cx38), its biophysical characteristics at single channel level are poorly understood. In this study, we performed single channel recordings from single Xenopus oocytes to acquire the biophysical properties of Cx38 including voltage-dependent gating and permeation (conductance and selectivity). The voltage-dependent fast and slow gatings of Cx38 hemichannel are distinct. Fast gating events occur at positive potentials and their open probabilities are low. In contrast, slow gatings dominate at negative potentials with high open probabilites. Based on hi-ionic experiments, Cx38 hemichannel is anion-selective. It will be interesting to test whether charged amino acid residues in the amino terminus of Cx38 are responsible for voltage gatings and permeation.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.34-40
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• 2014

Mesoporous SAPO-34 catalyst was successfully synthesized by the hydrothermal method using carbon nanotube (CNT) as a secondary template. The effects of CNT contents (0.5, 1.5, 2.5, and 4.5 mol%) on catalytic performances were investigated. The synthesized catalysts were characterized with XRD, SEM, nitrogen physisorption isotherm and $NH_3$-TPD. Among the synthesized catalysts, SAPO-34 catalyst prepared by the addition of 1.5 mol% CNT (1.5C-SAPO-34) observed not only the largest amounts of mesopore volume but also acid sites. However, the mesopore volume was relatively decreased by further increasing of CNT contents due to the formation of small crystalline. The catalytic lifetime and the selectivity of light olefins ($C_2{\sim}C_4$) were examined for the dimethyl ether to olefins reaction. As a result, the 1.5C-SAPO-34 catalyst showed an improvement of ca. 36% in a catalytic lifetime and a better selectivity to light olefins as compared with the general SAPO-34 catalyst.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.81-89
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• 2016

Double-stranded RNA (dsRNA) has been applied to control insect pests by its suppressive activity against specific target genes. Integrin is a heterodimer (${\alpha}$ and ${\beta}$) transmembrane protein and plays a critical role in cell-to-cell or cell-to-extracellular matrix interactions in eukaryotes. Suppression of ${\beta}$ subunit integrin gene expression by its specific dsRNA (= dsINT) induces significant mortality against target insects. Furthermore, a recombinant bacterium expressing dsINT is potent to kill target insects. However, it is necessary to develop a formulation technique of the dsRNA-expressing bacteria to apply the bacterial insecticide against field populations. This study formulated the recombinant bacteria by freeze-drying and tested its control efficacy against target insects. The formulation maintained significant insecticidal activity against last instar larvae of Spodoptera exigua. While a commercial Bacillus thuringiensis (Bt) insecticide exhibited only about 60% insecticidal activity against S. exigua last instar, an addition of the dsINT-expressing bacterial formulation significantly enhanced the Bt insecticidal activity. The dsINT-expressing bacterial formulation exhibited relative selectivity to target insects depending on sequence similarity. These results indicate that a freeze-dried form of dsRNA-expressing bacteria keeps its insecticidal activity.

• Food Science and Preservation
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• v.9 no.3
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• pp.338-344
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• 2002

This study was conducted to determine biological activities, such as lipid peroxidation inhibition and cytotoxic effect of ethanol extracts of Black Olympia grape seeds and skins, and of organic solvent fractionated ethanol extracts obtained from grape seeds and skins at different temperatures. Among different extraction temperatures, the ethanol extract of grape seed obtained at 30$\^{C}$ had the strongest lipid oxidation inhibition of 60.1%, while the strongest lipid oxidation inhibitory effect of 71.2% was observed in the presence of 20 $\mu\textrm{g}$/㎖ ethylacetate fraction obtained from ethanol extract of grape seeds at 30$\^{C}$. The ethanol extract of grape seeds showed more strong lipid oxidation inhibition than that of skin extracts. Similar results were observed in cytotoxic effects. The ethanol extract of grape seeds at 30$\^{C}$ exhibited more strong cytotoxicity than that of skin extracts on MCF-7, Hep3B, and A549 cell lines. Among organic solvent fractions extracted from the ethanol extracts of gape seeds and skins, the hexane fraction showed the strongest cytotoxic inhibition of 75.15% and 62.50% on MCF-7 and Hep3B cell in the presence of 1.0 $\mu\textrm{g}$/㎖ respectively. On the other hand, the water fraction showed the strongest cytotoxic inhibition of 65.41% on A549 cell in the presence of 1.0 $\mu\textrm{g}$/㎖. Overall, the ethanol extracts and their fractions of Black Olympia grape seeds showed strong lipid oxidation inhibition and cytotoxicity than those of grape skins.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.143-149
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• 2006

A extract from Spirulina platensis of seawater and freshwater was obtained by using the water and ethanol. Extraction yields of seawater S. platensis were observed about 3% higher than freshwater S. platensis. Cytotoxicity (HEK293) and inhibition ratio of cancer cell line (A549, AGS, MCF7, Hep3B) in adding of the extracts from the S. platensis of seawater and freshwater were measured by SRB assay. Cytotoxicity of all of the extracts in adding 1.0 mg/ml was below 26%. Ctotoxicity of the extracts from the seawater S. platensis were about 6% less than freshwater S. platensis. Inhibition ratio of cancer cell growth was inhibited by adding 1.0 mg/ml of the extracts that was obtained about 80%. Inhibition effect of cancer cell growth in adding seawater S. platensis was observed higher than freshwater S. platensis. Differentiation ratio of HL-60 cells in adding the extracts of seawater S. platensis was observed highly that was 160.9%.

• Journal of Life Science
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• v.18 no.9
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• pp.1305-1311
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• 2008

This study investigated that the antidiabetic effects of banaba extracts with variety solvents selectivity in vitro and in vivo. Banaba extracts were prepared with water, 70% ethanol, 90% ethanol, 100% ethanol and water-ethanol that of extract twice times sequentially water and ethanol. Cell toxicity and insulin secretion of banaba extracts was tested by MTT (3-[4,5-dimetylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay on hamster insulinoma cell line, HIT-T15. Also we tested that insulin, body weight, blood glucose, total cholesterol, HDL-cholesterol, triglyceride and free fatty acid in streptozotocin diabetic rats. Water-ethanol extract has remarkable antidiabetic effect compare with the other banaba extracts. For water-ethanol extract has both of hydrophilic and hydrophobic antidiabetic materials from banaba. Expecially, corosolic acid, as known as unique polyphenol, has antidiabetic effect studied by many researchers till nowadays. But corosolic acid does not solve in water. Otherwise, we suggest that banaba extract of hydrophilic and hydrophobic materials (polyphenol and antioxidants) mixture more increased antidiabetic effects.

• Korean Journal of Medicinal Crop Science
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• v.10 no.2
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• pp.109-115
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• 2002

The immune activation activities of ethanol, ethanol : water(1 : 1,v/v) and water extracts from Dendropanax morbifera Lev. were compared. The crude extracts showed relatively low cytotoxicity as less than 26% by using human normal liver cell(WRL-68). For example, the ethanol extract inhibited. in MCF7 and Hep3B cells in adding 1.0 mg/mL ethanol extracts. The growth of human immune T and B cells was enhanced up to $1.22{\sim}1.27$ times by adding the crude extracts. These are a trend of increasing secretion of $cytokines(IL-6,\;TNF-{\alpha})$ from human B/T cell for 6 day cultivation. It was found that the immune activation activities of the crude extracts seemed to be higher than those obtained by using other solvents.