• The Korean Journal of Physiology and Pharmacology
• /
• v.9 no.2
• /
• pp.109-115
• /
• 2005

Endothelial activation and subsequent recruitment of inflammatory cells are important steps in atherogenesis. The increased levels of cell adhesion molecules (CAM) have been identified in diabetic vasculatures, but the underlying mechanisms remain unclear. To determine the relationship among vascular production of superoxide, expression of CAM and diabetes, superoxide generation and expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E- and P-selectin in the aorta from control (C57BL/6J) and diabetic mice (ob/ob) were measured. In situ staining for superoxide using dihydroethidium showed an increased superoxide production in diabetic aorta, accompanied with an enhanced NAD(P)H oxidase activity. Immunohistochemical analysis revealed that the endothelial expression of ICAM-1 ($3.5{\pm}0.4$) and VCAM-1 ($3.8{\pm}0.3$) in diabetic aorta was significantly higher than those in control aorta ($0.9{\pm}0.5$ and $1.6{\pm}0.3$, respectively), accompanied with the enhanced expression of gp91phox, a membrane subunit of NAD(P)H oixdase. Furthermore, there was a strong positive correlation (r=0.89, P＜0.01 in ICAM-1 and r=0.88, P＜0.01 in VCAM-1) between ICAM-1/VCAM-1 expression and vascular production of superoxide. The present data indicate that the increased production of superoxide via NAD(P)H oxidase may explain the enhanced expression of CAM in diabetic vasculatures.

• Journal of Microbiology
• /
• v.44 no.2
• /
• pp.233-242
• /
• 2006

The objectives of this study were to optimize submerged culture conditions of a new fungal isolate, Ganorderma resinaceum, and to enhance the production of bioactive mycelial biomass and exopolysaccharides (EPS) by fed-batch culture. The maximum mycelial growth and EPS production in batch culture were achieved in a medium containing 10 g/l glucose, 8 g/l soy peptone, and 5 mM $MnCl_2$ at an initial pH 6.0 and temperature $31^{\circ}C$. After optimization of culture medium and environmental conditions in batch cultures, a fed-batch culture strategy was employed to enhance production of mycelial biomass and EPS. Five different EPS with molecular weights ranging from 53,000 to 5,257,000 g/mole were obtained from either top or bottom fractions of ethanol precipitate of culture filtrate. A fed-batch culture of G. resinaceum led to enhanced production of both mycelial biomass and EPS. The maximum concentrations of mycelial biomass (42.2 g/l) and EPS (4.6 g/l) were obtained when 50 g/l of glucose was fed at day 6 into an initial 10 g/l of glucose medium. It may be worth attempting with other mushroom fermentation processes for enhanced production of mushroom polysaccharides, particularly those with industrial potential.

• YAKHAK HOEJI
• /
• v.46 no.4
• /
• pp.258-264
• /
• 2002

Zinc plays an important role in immunobiological responses, while excessive zinc attenuates immune functions in a dose-dependent manner. Zinc excess has been reported to increase levels of plasma prostaglandin E$_2$ (PGE$_2$), which is known to inhibit production of Th (helper T) 1-associated cytokines and to induce inflammatory responses. Thus, this study was investigated the effects of indomethacin, a potent inhibitor of PGE$_2$ synthesis, on the proinflammatory cytokine and lymphokine production in ICR mice exposed to excessive zinc. Indomethacin at doses of 5 mg/kg was administered i.p. 30 minutes before zinc chloride (Zn) 30 mg/kg orally daily for 10 days. Excessive Zn remarkedly increased tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-1$\beta$ levels in both serum and splenic supernatants compared with those in controls, while indomethacin significantly reduced the excessive Zn-induced levels of IL-1$\beta$. In serum, excessive Zn significantly decreased the levels of IL-2 and interferon (IFN)-${\gamma}$ compared with those in controls, whereas indomethacin significantly enhanced the excessive Zn-decreased levels of IFN-${\gamma}$ but did not affect the Zn-decreased levels of serum IL-2. In splenic supernatants, All of excessive Zn, indomethacin, and combination of Zn and indomethacin significantly enhanced IL-2 levels compared with those in controls, but indomethacin didn't affect the Zn-induced production of IL-2. These data, therefore, suggest that indomethacin significantly attenuated the in vivo and ex vivo IL-1$\beta$ production increased by excessive zinc and remarkedly enhanced the in vivo excessive zinc-suppressed production of IFN-${\gamma}$ but not IL-2.

• KSBB Journal
• /
• v.11 no.6
• /
• pp.642-648
• /
• 1996

The effects of EDTA(Ethylene diamine tetraacetic acid), Cu, temperature, and gas(methane and oxygen) composition on methanol production from methane with Methylosinus trichosporium were investigated. In this experiment EDTA was found to be a potential methanol dehydrogenase inhibitor since it causes methanol accumulation and 6mM was found to be optimum concentration of EDTA for methanol production. When Cu was added in culture media, the produced methanol concentration level was increased. Hence it is believed that Cu enhanced the particulate methane monooxygenase formation and consequently the addition of Cu could increase the methanol production from methane. In this experiment the optimum concentration of Cu was found to be 1mM for methanol production. When temperature was shifted down from $30^{\circ}C to 25^{\circ}C$, the methanol production level was enhanced by 50%. When the ratio of methane to oxygen in gas phase was increased to 2.3 from 1, produced methanol concentration was also enhanced by 100%.

• Journal of Ginseng Research
• /
• v.43 no.1
• /
• pp.49-57
• /
• 2019

Background: Korean Red Ginseng (KRG; Panax ginseng Meyer) is a widely used medicinal herb known to exert various immune modulatory functions. KRG and one of its purified components, ginsenoside Rg3, are known to possess anti-inflammatory activities. How they impact helper T cell-mediated responses is not fully explored. In this study, we attempted to evaluate the effect of KRG extract (KRGE) and ginsenoside Rg3 on Th1 cell responses. Methods: Using well-characterized T cell in vitro differentiation systems, we examined the effects of KRGE or enhanced Rg3 on the Th1-inducing cytokine production from dendritic cells (DC) and the naïve $CD4^+$ T cells differentiation to Th1 cells. Furthermore, we examined the change of Th1 cell population in the intestine after treatment of enhanced Rg3. The influence of KRGE or enhanced Rg3 on Th1 cell differentiation was evaluated by fluorescence-activated cell sorting, enzyme-linked immunosorbent assay, and quantitative real-time polymerase chain reaction. Results: KRGE significantly inhibited the production level of IL-12 from DCs and subsequent Th1 cell differentiation. Similarly, enhanced Rg3 significantly suppressed the expression of interferon gamma ($IFN{\gamma}$) and T-bet in T cells under Th1-skewing condition. Consistent with these effects in vitro, oral administration of enhanced Rg3 suppressed the frequency of Th1 cells in the Peyer's patch and lamina propria cells in vivo. Conclusion: Enhanced Rg3 negatively regulates the differentiation of Th1 cell in vitro and Th1 cell responses in the gut in vivo, providing fundamental basis for the use of this agent to treat Th1-related diseases.

• Journal of Microbiology and Biotechnology
• /
• v.2 no.4
• /
• pp.284-287
• /
• 1992

Repeated-batch and continuous cultures of Lactococcus sp. 1112-1 were carried out for bacteriocin production using a glucose-casein medium. Repeated-batch culture did not efficiently enhanced the bacteriocin production. Continuous production was possible at the dilution rate of 0.4 $h^{-1}$. Maximum specific production rate ($Q^p$), bacteriocin production and biomass at the dilution rate were 347, 136 IU/g/h, 2, 121 IU/ml and 2.45 g/L, respectively.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.26 no.5
• /
• pp.742-749
• /
• 2002

Numerical Study with detailed chemistry has been conducted to investigate the flame structure and NOx formation characteristics in oxygen -enhanced(CH$_4$/O$_2$-$N_2$) and oxygen-enhanced-EGR(CH$_4$/O$_2$-$CO_2$) counter diffusion flame with various strain rates. A small amount of $N_2$is included in oxygen-enhanced-EGR combustion, in order to consider the inevitable $N_2$contamination by $O_2$production process or air infiltration. The results are as follows : In CH$_4$/O$_2$-$CO_2$flame it is very important to adopt a radiation effect precisely because the effect of radiation changes flame structure significantly. In CH$_4$/O$_2$-$N_2$flame special strategy to minimize NO emission is needed because it is very sensitive to a small amount of $N_2$. Special attention is needed on CO emission by flame quenching, because of increased CO concentration. Spatial NO production rate of oxygen-enhanced combustion is different from that of air and oxygen-enhanced-EGR combustion in that thermal mechanism plays a role of destruction as well as production. In case CH$_4$/O$_2$-$CO_2$flame contains more than 40% $CO_2$it is possible to maintain the same EINO as that of CH$_4$/Air flame with accomplishing higher temperature than that of CH$_4$/Air flame. EINO decreases with increasing strain rate, and those effects are augmented in CH$_4$/O$_2$flame.

• Proceedings of the KSME Conference
• /
• 2001.11b
• /
• pp.185-190
• /
• 2001

Numerical Study with detailed chemistry has been conducted to investigate the flame structure and NOx formation characteristics in oxygen-enhanced$(CH_4/O_2-N_2)$ and oxygen-enhanced-EGR$(CH_4/O_2-CO_2)$ counter diffusion flame with various strain rates. A small amount of $N_2$ is included in oxygen-enhanced-EGR combustion, in order to consider the inevitable $N_2$ contamination by $O_2$ production process or air infiltration. The results are as follows : In $CH_4/O_2-CO_2$ flame it is very important to adopt a radiation effect precisely because the effect of radiation changes flame structure significantly. In $CH_4/O_2-N_2$ flame special strategy to minimize NO emission is needed because it is very sensitive to a small amount of $N_2$. Special attention is needed on CO emission by flame quenching, because of increased CO concentration. Spatial NO production rate of oxygen-enhanced combustion is different from that of air and oxygen-enhanced-EGR combustion in that thermal mechanism plays a role of destruction as well as production. In case $CH_4/O_2-CO_2$ flame contains more than 40% $CO_2$ it is possible to maintain the same EINO as that of $CH_4/Air$ flame with accomplishing higher temperature than that of $CH_4/Air$ flame. EINO decreases with increasing strain rate, and those effects are augmented in $CH_4/O_2$ flame. Complementary study is needed with extending the range of strain rate variation.

• The Korean Journal of Physiology and Pharmacology
• /
• v.13 no.2
• /
• pp.99-106
• /
• 2009

Although anti-atherogenic effects of cilostazol have been suggested, its effects on the expression of SR in macrophages are unclear. This study investigated the role of cilostazol on CD36 expression of murine macrophages enhanced by HNE, a byproduct of lipid peroxidation. The stimulation of macrophages with HNE led to an increased expression of CD36, which was significantly attenuated by NAC, an antioxidant. Moreover, the increased production of ROS by HNE was completely abolished by NADPH oxidase inhibitors, DPI and apocynin, as well as by the 5-LO inhibitor, MK886, but not by inhibitors for other oxidases. This suggested that NADPH-oxidase and 5-LO were major sources of ROS induced by HNE. In addition, HNE-enhanced expression of CD36 was reduced by these inhibitors, which indicated a role for NADPH oxidase and 5-LO on CD36 expression. In our present study, cilostazol was a significant inhibitor of ROS production, as well as CD36 expression induced by HNE. An increase in NADPH oxidase activity by HNE was significantly attenuated by cilostazol, however cilostazol had no effect on HNE-enhanced 5-LO activity. Together, these results suggest that cilostazol attenuates HNE-enhanced CD36 expression on murine macrophages thorough inhibition of NADPH oxidase-derived ROS generation.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.12
• /
• pp.1937-1943
• /
• 2020

Although classical metabolic engineering strategies have succeeded in developing microbial strains capable of producing desired bioproducts, metabolic imbalance resulting from extensive genetic manipulation often leads to decreased productivity. Thus, abiotic strategies for improving microbial production performance can be an alternative to overcome drawbacks arising from intensive metabolic engineering. Herein, we report a promising abiotic method for enhancing lycopene production by UV-C irradiation using a radiation-resistant ΔcrtLm/crtB+dxs+ Deinococcus radiodurans R1 strain. First, the onset of UV irradiation was determined through analysis of the expression of 11 genes mainly involved in the carotenoid biosynthetic pathway in the ΔcrtLm/crtB+dxs+ D. radiodurans R1 strain. Second, the effects of different UV wavelengths (UV-A, UV-B, and UV-C) on lycopene production were investigated. UV-C irradiation induced the highest production, resulting in a 69.9% increase in lycopene content [64.2 ± 3.2 mg/g dry cell weight (DCW)]. Extended UV-C irradiation further enhanced lycopene content up to 73.9 ± 2.3 mg/g DCW, a 95.5% increase compared to production without UV-C irradiation (37.8 ± 0.7 mg/g DCW).