• Journal of Ginseng Research
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• v.37 no.4
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• pp.379-388
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• 2013

Diabetic nephropathy is one of the serious complications in patients with either type 1 or 2 diabetes mellitus but current treatments remain unsatisfactory. Results of clinical research studies demonstrate that Panax ginseng can help adjust blood pressure and reduce blood sugar and may be advantageous in the treatment of tuberculosis and kidney damage in people with diabetes. The heat-processing method to strengthen the efficacy of P. ginseng has been well-defined based on a long history of ethnopharmacological evidence. The protective effects of P. ginseng on pathological conditions and renal damage associated with diabetic nephropathy in the animal models were markedly improved by heat-processing. The concentrations of less-polar ginsenosides (20(S)-Rg3, 20(R)-Rg3, Rg5, and Rk1) and maltol in P. ginseng were significantly increased in a heat-processing temperature-dependent manner. Based on researches in animal models of diabetes, ginsenoside 20(S)-Rg3 and maltol were evaluated to have therapeutic potential against diabetic renal damage. These effects were achieved through the inhibition of inflammatory pathway activated by oxidative stress and advanced glycation endproducts. These findings indicate that ginsenoside 20(S)-Rg3 and maltol are important bioactive constituents of heat-processed ginseng in the control of pathological conditions associated with diabetic nephropathy.

• Nano
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• v.13 no.11
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• pp.1850127.1-1850127.13
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• 2018

Bi metal deposited on $Bi_2MoO_6$ composite photocatalysts have been successfully synthesized via a simple reduction method at room temperature with using $NaBH_4$ as the reducing agent. The photocatalytic activity of the composite was evaluated by degradation of rhodamine B (RhB) and bisphenol A (BPA) solution under visible light. The rate constant of $Bi/Bi_2MoO_6$ composite to RhB is 10.8 times that of $Bi_2MoO_6$, and the degradation rate constant of BPA is 6.9 times of that of $Bi_2MoO_6$. Nitrogen absorption-desorption isotherm proved that the increase of specific surface area is one of the reasons for the improvement of photocatalytic degradation activity of $Bi/Bi_2MoO_6$ composites. The higher charge transfer efficiency of $Bi/Bi_2MoO_6$ is found through the characterization of the photocurrent and impedance, which are attributed to the surface plasmon resonance (SPR) effect produced by the introduction of the metal Bi monomer in the composite. Free radical capture experiments proved that cavitation is the main active species. Based on the above conclusions, a possible mechanism of photocatalytic degradation is proposed.

• Biomedical Science Letters
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• v.24 no.4
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• pp.357-364
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• 2018

Manganese (Mn) is used as main materials in various chemical processes of industry, but it suggested that Mn brings about its toxicant by fume or dust through respiratory system and skin barrier. Mn toxicant induces the loss of mental health and life quality by cerebrovascular and skin diseases. Nevertheless, it lefts much unknown on the mechanism and the effectively therapeutic methods about Mn toxicant. Therefore, this study was evaluated the cytotoxicity induced by manganese dioxide ($MnO_2$) in cultured NIH3T3 fibroblasts, and also, the correlation between $MnO_2$-induced cytotoxicity and oxidative stress was examined. While, the effect of Eclipta prostrata L. (EP) extract belong to Compositae was assessed against $MnO_2$-induced cytotoxicity in the view of antioxidative effect for searching the natural resources mitigating or preventing the $MnO_2$-induced cytotoxicity. In this study, $MnO_2$-induced cytotoxicity was revealed as mid-toxic by Borenfreud and Puerner's toxic criteria, and catalase (CAT), an antioxidant prevented $MnO_2$-induced cytotoxicity by the remarkable increase of cell viability in these cultures. While, in the protective effect of EP extract on $MnO_2$-induced cytotoxicity, EP extract effectively prevented the cytotoxicity induced by $MnO_2$ via antioxidative effects such as xanthine oxidase (XO) inhibitory ability and DPPH-radical scavenging ability. From the above results, EP extract showed the effective prevention against $MnO_2$-induced cytotoxicity correlated with oxidative stress by antioxidative effects. Conclusively, this study may be useful to research or development the alternatively therapeutic agent from natural resources like EP extract for the treatment of diseases resulted in oxidative stress.

• Journal of Korea Trade
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• v.24 no.3
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• pp.37-54
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• 2020

Purpose - This study is to investigate the determinants of suppliers' dependence on buyers in the home country by developing a theoretical model of innovative activities. The high dependence of auto parts suppliers on a single local buyer in South Korea due to firm ownership issues and incremental innovation is examined using data from a set of organizations that supply intermediate goods to this automotive manufacturer. Furthermore, we tested the moderating effect of FDI and global knowledge sourcing on the relationship between firm ownership and suppliers' dependence on the local buyer. Design/methodology - To test the hypotheses, we examined a sample of 101 suppliers over 10 years in the Korean automobile parts industry. In this empirical analysis, we utilized a fixed-effects generalized least squares model using panel data. Findings - In this study, domestic firms (automobile parts suppliers) were more dependent on a single local buyer (automobile assembler) than foreign-owned suppliers operating in Korea. In addition, incremental innovation was the mediating mechanism between domestic firms and dependence on the local buyer. To reduce this dependence on the buyer, we suggest two different international strategies: geographical diversification through FDI and global knowledge sourcing. Originality/value - Previous studies showed that asymmetric dependence between firms has many adverse effects. This study proved that domestic and foreign-owned suppliers have different levels of dependence on local buyers due to their heterogeneous characteristics and business strategies. We distinguish two different types of innovation - radical innovation and incremental innovation - that previous studies have often treated as equal when it comes to firm autonomy. Finally, we propose that both FDI and international knowledge sourcing as global strategies to weaken suppliers' asymmetric dependence on a single buyer.

• Journal of Veterinary Science
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• v.23 no.3
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• pp.48.1-48.12
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• 2022

Background: The poor intracellular concentration of enrofloxacin might lead to treatment failure of cow mastitis caused by Staphylococcus aureus small colony variants (SASCVs). Objectives: In this study, enrofloxacin composite nanogels were developed to increase the intracellular therapeutic drug concentrations and enhance the efficacy of enrofloxacin against cow mastitis caused by intracellular SASCVs. Methods: Enrofloxacin composite nanogels were formulated by an electrostatic interaction between gelatin (positive charge) and sodium alginate (SA; negative charge) with the help of CaCl₂ (ionic crosslinkers) and optimized by a single factor test using the particle diameter, zeta potential (ZP), polydispersity index (PDI), loading capacity (LC), and encapsulation efficiency (EE) as indexes. The formation mechanism, structural characteristics, bioadhesion ability, cellular uptake, and the antibacterial activity of the enrofloxacin composite nanogels against intracellular SASCVs strain were studied systematically. Results: The optimized formulation was comprised of 10 mg/mL (gelatin), 5 mg/mL (SA), and 0.25 mg/mL (CaCl₂). The size, LC, EE, PDI, and ZP of the optimized enrofloxacin composite nanogels were 323.2 ± 4.3 nm, 15.4% ± 0.2%, 69.6% ± 1.3%, 0.11 ± 0.02, and -34.4 ± 0.8 mV, respectively. Transmission electron microscopy showed that the enrofloxacin composite nanogels were spherical with a smooth surface and good particle size distributions. In addition, the enrofloxacin composite nanogels could enhance the bioadhesion capacity of enrofloxacin for the SASCVs strain by adhesive studies. The minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration, and minimum biofilm eradication concentration were 2, 4, 4, and 8 ㎍/mL, respectively. The killing rate curve had a concentration-dependent bactericidal effect as increasing drug concentrations induced swifter and more radical killing effects. Conclusions: This study provides a good tendency for developing enrofloxacin composite nanogels for treating cow mastitis caused by intracellular SASCVs and other intracellular bacterial infections.

• The Korea Journal of Herbology
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• v.38 no.6
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• pp.29-44
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• 2023

Objectives : This study was planned to evaluate the therapeutic effectiveness and possible underlying mechanism of TPE (Tetrapanax papyrifer stem(inner part of the stem Extract) and AQE (Akebiae quinata stem Extract) on osteoarthritis. Methods : Osteoarthritis models were induced through intra-articular injection of MIA (monosodium iodoacetate) 50 μL with 80 mg/ml in rats. Excluding the normal group, Osteoarthritis-induced rats were divided into 4 groups (Control, INDO, TPE, AQE). The drug concentrations were indomethacin 5 mg/kg, TPE 200 mg/kg, and AQE 200 mg/kg, and were orally administered once a day for a couple of weeks. After drug supplementation, the effects of TPE and AQE were measured with serum diagnosis, western blotting, and histopathological staining. Results : It was found that the DPPH and ABTS free radical erasure ability of AQE was better than that of TPE. AQE administration improved rear limb overload and it led to relieving pain. Both PTE and AQE significantly reduced the expression of inflammatory mediators COX-2, iNOS, and inflammatory cytokine IL-1β and IL-6 by inhibiting the phosphorylation of IκBα and deactivating the pathway of NF-κBp65. On the other hand, TNF-α was significantly reduced only by administration of AQE. In addition, histopathological analysis showed that the administration of AQE compared to PTE suppressed cartilage degeneration and effectively suppressed damage to proteoglycan, a component of ECM. Conclusion : Reviewing these experimental results, TPE and AQE possessed the effect of delaying the progress of osteoarthritis and protecting cartilage. In addition, the results of this study show that AQE has a better cartilage protection effect than TPE.

• Animal Bioscience
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• v.37 no.2_spc
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• pp.396-403
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• 2024

Objective: Monofluoroacetate (MFA) is a potent toxin that blocks ATP production via the Krebs cycle and causes acute toxicity in ruminants consuming MFA-containing plants. The rumen bacterium, Cloacibacillus porcorum strain MFA1 belongs to the phylum Synergistota and can produce fluoride and acetate from MFA as the end-products of dehalorespiration. The aim of this study was to identify the genomic basis for the metabolism of MFA by this bacterium. Methods: A draft genome sequence for C. porcorum strain MFA1 was assembled and quantitative transcriptomic analysis was performed thus highlighting a candidate operon encoding four proteins that are responsible for the carbon-fluorine bond cleavage. Comparative genome analysis of this operon was undertaken with three other species of closely related Synergistota bacteria. Results: Two of the genes in this operon are related to the substrate-binding components of the glycine reductase protein B (GrdB) complex. Glycine shares a similar structure to MFA suggesting a role for these proteins in binding MFA. The remaining two genes in the operon, an antiporter family protein and an oxidoreductase belonging to the radical S-adenosyl methionine superfamily, are hypothesised to transport and activate the GrdB-like protein respectively. Similar operons were identified in a small number of other Synergistota bacteria including type strains of Cloacibacillus porcorum, C. evryensis, and Pyramidobacter piscolens, suggesting lateral transfer of the operon as these genera belong to separate families. We confirmed that all three species can degrade MFA, however, substrate degradation in P. piscolens was notably reduced compared to Cloacibacillus isolates possibly reflecting the loss of the oxidoreductase and antiporter in the P. piscolens operon. Conclusion: Identification of this unusual anaerobic fluoroacetate metabolism extends the known substrates for dehalorespiration and indicates the potential for substrate plasticity in amino acid-reducing enzymes to include xenobiotics.

• Journal of Life Science
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• v.28 no.6
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• pp.708-717
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• 2018

The antioxidant activity and protective effects of a hot water extract from the Stauntonia hexaphylla fruit (WESHF) were investigated in vitro and in vivo. The total polyphenol and flavonoid contents of WESHF were $16.13{\pm}0.27mg$ gallic acid equivalent/g and $4.7{\pm}0.80mg$ catechin equivalent/g, respectively. In addition, the DPPH radical-scavenging activity ($SC_{50}$) and the Oxygen Radical Absorbance capacity of WESHF were $63.62{\pm}4.10{\mu}g/ml$ and $90.63{\pm}5.29{\mu}M$ trolox equivalent/g, respectively. The hepatoprotective effect of WESHF against hydrogen peroxide-induced oxidative damage was investigated. $H_2O_2$-induced liver damage on HepG2 cells was prevented by $200{\mu}g/ml$ of WESHF. Furthermore, to investigate the protection mechanism of WESHF on hydrogen peroxide-induced cytotoxicity in HepG2 cells, pre-treatment with $200{\mu}g/ml$ of WESHF significantly attenuated a decrease in the activities of CAT, SOD, GR, and GPx. The hepatoprotective activity of WESHF was evaluated in an experimental model of hepatic damage induced by acetaminophen (APAP). The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly decreased in the livers of mice treated with 200 mg/kg of WESHF compared to the APAP-treated group. The lipid peroxidation level, which increased after APAP administration, was significantly reduced in the WESHF group. In addition, histological examinations of the liver showed the same protective effect of WESHF treatment. Based on these findings, it is suggested that WESHF has potent hepatoprotective effects, and the mechanism that causes this type of protection could be related to antioxidant pathways.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.639-648
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• 2010

The optimal conditions for the analysis of BPA by HPLC-MS/MS was investigated and the ultrasound degradation capacity of the BPA, with the goal to establish the proper directions for analyzing infinitesimal quantities of BPA by HPLC-MS/MS was examined. The MDL and LOQ of BPA analyzed by HPLC-MS/MS were measured 0.13 nM and 1.3 nM respectively, its sensitivity about 620 and 32 times greater than HPLC-UV (MDL: 81.1 nM, LOQ: 811 nM) and FLD (MDL: 4.6 nM, LOQ: 46 nM). In other words, the new method enables the analysis of BPA with the accuracy up to one 1,180th of the amount specified in U.S. EPA guideline for drinking water. Degradation rate of BPA by ultrasound measured over 95% under 580 kHz and 1000 kHz frequency within 30 minutes of treatment, whereas the rate showed some decrease at 28 kHz frequency. At 580 kHz of ultrasound has proven to be the most effective among others at degradation rate and $k_1$ value, so we concluded that this frequency of ultrasound creates hospitable condition for the combined process of degradation by pyrolysis and oxidization. With the addition of 0.01 mM of $CCl_4$, BPA with the initial concentration of 1 ${\mu}M$ was degraded by more than 98% within 30 minutes, the $k_1$ value measured 5 minutes and 30 minutes into the experiment both showed increases by 1.4 and 1.1 times, respectively, compared with BPA without $CCl_4$. It is also found that the main degradation mechanism of BPA by ultrasound is oxidization process by OH radical, based on the fact that the addition of 10 mM of t-BuOH decreased the rate of BPA degradation by around 60%. However, 33% of BPA degradation rate obtained with the addition of t-BuOH implies further degradation done by pyrolysis or other sorts of radical beside OH radical.

• Food Science and Preservation
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• v.18 no.3
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• pp.366-373
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• 2011

Recent studies suggested that Cheonnyuncho is a significant source of bioactive phenolic compounds, comparable to phytochemicals, including green tea and onion. In this study, the hot-water and 80% ethanolic extracts of Cheonnyuncho were assessed as to their total phenol content, total flavonoids content, antioxidant activity (DPPH radical-scavenging activity and reducing power), and anti-obesity activity. The results showed that the total phenol contents of the hot water extract and the 80% ethanolic extract were $16.52{\pm}3.87$ and $13.44{\pm}0.85$ mg GAE/g, respectively. The total flavonoids content was detected only in the 80% ethanolic extract, however, with a 778.08 ${\mu}g$ catechin equivalents/g content. The DPPH radical-scavenging activity and reducing power of the 80% ethanolic extract from Cheonnyuncho was significantly higher than those of the water extract (p < 0.05). During the adipocyte differentiation, the 80% ethanolic extract of Cheonnyuncho more significantly inhibited lipid accumulation and ROS production than the 3T3-L1 cells that were treated with hot water extract. Furthermore, the 80% ethanolic extract of Cheonnyuncho suppressed the mRNA abundance of the adipogenic transcription factor, $PPAR{\gamma}$ (peroxisome proliferator-activated receptor ${\gamma}$), and its target gene, aP2 (adipocyte protein 2). These results indicate that Cheonnyuncho extracts can inhibit adipogenesis through a mechanism that involves direct down regulation of $PPAR{\gamma}$ gene expression or via modulation of ROS production associated with radical-scavenging activities.