Purpose: Glabridin (GD) is a bio-available isoflavane isolated from the root extract of licorice (Glycyrrhiza glabra L.). It exhibits a variety of pharmacological activities such as anti-inflammatory and anti-oxidant activities. However, extracellular vesicles (EVs) secretion and the anti-cancer mechanism of action remains largely unknown. The present study investigates the anticancer effects of GD by determining the inhibition of EVs secretion in the human breast cancer cell line, MDA-MB-231. Methods: Cell viability, reactive oxygen species (ROS) production, migration, invasion rate, and vascular endothelial growth factor (VEGF) concentration were assessed in MDA-MB-231 cells treated with increasing concentrations of GD (0.1, 1, 5, 10, 20 µM). Subsequently, EV secretion and exosomal DEL-1 protein expression were evaluated to determine the anticancer effects of GD. Results: The results showed that GD significantly inhibited the cell proliferation of MDA-MB-231 cells in a dose- or time-dependent manner. Also, ROS production and apoptosis marker protein cleaved caspase-3 were significantly increased in GD-treated MDA-MB-231, compared to control. Furthermore, GD exposure resulted in significantly decreased not only migration and invasion rates but also the VEGF concentration, thereby contributing to a reduction in angiogenesis. Interestingly, the concentration and number of EVs as well as EV marker proteins, such as CD63 and TSG101, were decreased in GD-treated MDA-MB-231 cells. Markedly, extracellular matrix protein DEL-1 as angiogenesis factor was decreased in EVs from GD-treated MDA-MB-231 cells. Conclusion: This study identifies that the anti-cancer molecular mechanism of GD is exerted via inhibition of angiogenesis and EVs secretion, indicating the potential of GD as a chemotherapeutic agent for breast cancer.
Jun-Tae Kim;Sung-Ho Cho;Do-Youn Jeong;Young-Soo Kim
Food Science and Preservation
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v.30
no.1
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pp.132-145
/
2023
In this study, culture conditions were optimized to confirm the feasibility of Acetobacter pasteurianus as a starter for fermentation vinegar. Acetobacter pasteurianus strain can be used as a food ingredient. The optimal temperature and pH conditions of the selected Acetobacter pasteurianus SRCM101388 were 28℃ and pH 6.00, respectively. The response surface methodology (RSM) was used to optimize the composition of the medium, and Plackett-Burman design (PBD) was used to obtain the effective selection of culture medium, resulting in that glucose, sucrose, and yeast extract had the highest effect on increasing biomass. The optimal concentration, which was performed by central composite design (CCD), were determined to be 10.73 g/L of glucose, 3.98 g/L of sucrose, and 18.73 g/L of yeast extract, respectively. The optimal concentrations of trace elements for the production of biomass were found to be 1 g/L of ammonium sulfate, 0.5 g/L of magnesium sulfate, 2 g/L of sodium phosphate monobasic, 2 g/L of sodium phosphate dibasic, and the final optimized medium was pH 6.10. When incubated in a 5 L jar fermenter, the SRCM101388 strain showed a faster-dissolved oxygen (DO) reduction at a lower agitation rate (rpm), and it was able to grow even at reduced DO level when aeration was maintained. The amount of final biomass produced was 2.53±0.12×109 CFU/mL (9.40±0.02 log CFU/mL) when incubated for 18 hours at 150 rpm, 0.5 vvm, pH 6.0, and 28℃.
Kim, Young-Il;Paik, Il-Young;Kwak, Yi-Sub;Kim, Keun-Soo;Woo, Jin-Hee
Journal of Life Science
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v.19
no.5
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pp.625-632
/
2009
The purpose of this study was to examine the effect of exercise training on nitric oxide (NO) levels, mean arterial pressure (MAP), blood pressure (BP), and heart rate (HR) in college students. 5 subjects were randomly assigned to two experimental groups; an aerobic training group (ATG) and a resistance training group (RTG). In aerobic training, based on measured maximum oxygen consumption rate, 70% exercise intensity was applied and conducted for 60 min. In resistance training, 70% of 1-RM was performed for 90 min. Blood sampling was conducted 3 times during resting state, post-exercise, and after 30 minutes of recovery. The results are as followed. For the post training values of $VO_2max$, % body fat and MAP, there were significant differences in the ATG compared to pre training (p<0.05). However, there were no differences in the RTG between pre and post training. NO increased post training, during rest and at the end of exercise compared to pre training in the ATG (p<0.05). Also, the HR decreased in post training at the end of exercise (p<0.05), however, there were no significant differences in SBP and DBP between pre and post training in the ATG. The HR, SBP and DBP did not change at all in post training compared to pre training in the RTG. In conclusion, an increase in the production of Nitric Oxide (NO) concentration and $VO_2max$, decrease of body fat% and physiological variables (HR, BP, MAP) were shown to be more effective in aerobic training (AT) than resistance training (RT).
Yun, Sang Yeop;Jung, Ho Chul;Lee, In-Beum;Chang, Kun Soo
제어로봇시스템학회:학술대회논문집
/
1991.10b
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pp.1639-1645
/
1991
Because of the important role LD converters play in the production of high quality steel, various dynamic models have been attempted in the past by many researchers not only to understand the complex chemical reactions that take place in the converter process but also to assist the converter operation itself using computers. And yet no single dynamic model was found to be completely satisfactory because of the complexity involved with the process. The process indeed involves dynamic energy and mass balances at high temperatures accompanied by complex chemical reactions and transport phenomena in the molten state. In the present study, a mathematical model describing the dynamic behavior of LD converter process has been developed. The dynamic model describes the time behavior of the temperature and the concentrations of chemical species in the hot metal bath and slag. The analysis was greatly facilitated by dividing the entire process into three zones according to the physical boundaries and reaction mechanisms. These three zones were hot metal (zone 1), slag (zone 2) and emulsion (zone 3) zones. The removal rate of Si, C, Mn and P and the rate of Fe oxidation in the hot metal bath, and the change of composition in the slag were obtained as functions of time, operating conditions and kinetic parameters. The temperature behavior in the metal bath and the slag was also obtained by considering the heat transfer between the mixing and the slag zones and the heat generated from chemical reactions involving oxygen blowing. To identify the unknown parameters in the equations and simulate the dynamic model, Hooke and Jeeves parttern search and Runge-Kutta integration algorithm were used. By testing and fitting the model with the data obtained from the operation of POSCO #2 steelmaking plant, the dynamic model was able to predict the characteristics of the main components in the LD converter. It was possible to predict the optimum CO gas recovery by computer simulation
This study analyzed the groundwater quality according to the depth and geological features in Gyeongsangnam-do area using groundwater quality monitoring network data to grasp the groundwater quality characteristics and to provide basic data for policy making on efficient groundwater management. Five hundred and three data sets were acquired from background water quality exclusive monitoring network in soil groundwater information system for five years (2013 ~ 2017). Except for the total coliforms and tracer items such as mercury, phenol, and others, the parameters of water quality were significant or very significant, depending on depth and geological features. As the depth got deeper, the average value of pH and electrical conductivity increased; water temperature, dissolved oxygen, oxide reduction potential, arsenic, total coliforms, and turbidity decreased; and total unfit rate for drinking water standards was lower. It was found that the sum of the positive and negative ions was the highest in the clastic sedimentary rock and the lowest in metamorphic rock. The total unfit rate for drinking water standards was the highest for metamorphic rocks, followed by clastic sedimentary rock and unconsolidated sediments and, finally, intrusive igneous rock with the lowest penetration. The Na-Cl water type, which indicated the possibility of contamination by external pollutants, appeared only at some points in shallow depths and in clastic sedimentary rocks.
Glucose fed-batch culture was studied to improve cellulose productivity by Acetobacter xylinum BRC5. When initial glucose concentrations in batch cultures were less than 20 g/L, yield coefficients of cellulose (Yp/s) remained a constant value of 0.21 g cellulose/g glucose. But a low yield coefficient, Yp/s=0.13 was obtained from an initial glucose concentration of 40 g/L. Since initial high glucose concentrations in batch culture resulted in low yields of cellulose, constant fed-batch cultures were carried out. The optimal feed rate for fed-batch culture was 2.22 g glucose/L.h. In constant fed-batch culture without DO control, 10 g/L of cellulose was obtained from 40 g/L of glucose with this feed rate, which was approximately two fold higher than that of the batch culture with the same initial glucose concentration. In DO stat plus fed-batch culture, the highest cellulose productivity could be obtained when dissolved oxygen level was controlled at 10% of air saturation, and cellulose productivity increased about 1.5 times compared with that of the culture without DO control.
Journal of Advanced Marine Engineering and Technology
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v.41
no.3
/
pp.182-190
/
2017
All liquids contain a small amount of gaseous components and the amount of gases dissolved in a liquid is in accordance with Henry's Law. In a multi-stage thermal-type seawater desalination plant, as the supplied seawater undergoes variations in temperature and pressure in each evaporator, the gases dissolved in the seawater are discharged from the liquid. The discharged gases are carbon dioxide, nitrogen, oxygen, and argon, and these emitted gases are non-condensable. From the viewpoint of convective heat transfer, the evaluation of non-condensable gas released during a vacuum evaporation process is a very important design factor because the non-condensable gases degrade the performance of the cooler. Furthermore, in a thermal-type seawater desalination plant, most evaporators operate under vacuum, which maintained through vacuum system such as a steam ejector or a vacuum pump. Therefore, for the proper design of a vacuum system, estimating the non-condensable gases released from seawater is highly crucial. In the study, non-condensable gases released in a thermal-type seawater desalination plant were calculated quantitatively. The calculation results showed that the NCG releasing rate decreased as the stage comes getting a downstream and it was proportional to the freshwater production rate.
Hwang, Eunmi;Kim, Gye Won;Song, Ki Duk;Lee, Hak-Kyo;Kim, Sung-Jo
Asian-Australasian Journal of Animal Sciences
/
v.32
no.11
/
pp.1776-1788
/
2019
Objective: The demands for measures to improve disease resistance and productivity of livestock are increasing, as most countries prohibit the addition of antibiotics to feed. This study therefore aimed to uncover functional feed additives to help enhance livestock immunity and disease resistance, using Acanthopanax sessiliflorus fruit extract (ASF). Methods: ASF was extracted with 70% EtOH, and total polyphenolic and catechin contents were measured by the Folin-Ciocalteu and vanillin assay, respectively. The 3D4/31 porcine macrophage cells ($M{\Phi}$) were activated by phorbol 12-myristate 13-acetate (PMA), and cell survival and growth rate were measured with or without ASF treatment. Flow-cytometric analysis determined the lysosomal activity, reactive oxygen species levels (ROS), and cell cycle distribution. Nuclear factor kappa B ($NF-{\kappa}B$) and superoxide dismutase (SOD) protein expression levels were quantified by western blotting and densitometry analysis. Quantitative polymerase chain reaction was applied to measure the lipid metabolism-related genes expression level. Lastly, the antibacterial activity of 3D4/31 $M{\Phi}$ cells was evaluated by the colony forming unit assay. Results: ASF upregulated the cell viability and growth rate of 3D4/31 $M{\Phi}$, with or without PMA activation. Moreover, lysosomal activity and intracellular ROS levels were increased after ASF exposure. In addition, the antioxidant enzyme SOD2 expression levels were proportionately increased with ROS levels. Both ASF and PMA treatment resulted in upregulation of $NF-{\kappa}B$ protein, tumor necrosis factor $(TNF){\alpha}$ mRNA expression levels, lipid synthesis, and fatty acid oxidation metabolism. Interestingly, co-treatment of ASF with PMA resulted in recovery of $NF-{\kappa}B$, $TNF{\alpha}$, and lipid metabolism levels. Finally, ASF pretreatment enhanced the in vitro bactericidal activity of 3D4/31 $M{\Phi}$ against Escherichia coli. Conclusion: This study provides a novel insight into the regulation of $NF-{\kappa}B$ activity and lipid metabolism in $M{\Phi}$, and we anticipate that ASF has the potential to be effective as a feed additive to enhance livestock immunity.
Objective: Gram-negative bacteria lipopolysaccharide (LPS) has been reported to be associated with uterine impairment, embryonic resorption, ovarian dysfunction, and follicle retardation. Here, we aimed to investigate the toxic effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes. Methods: First, we developed an in vitro model to study the response of bovine cumulusoocyte complexes (COCs) to LPS stress. After incubating germinal vesicle COCs in $10{\mu}g/mL$ of LPS, we analyzed the following three aspects: the expression levels of the LPS receptor toll-like receptor 4 (TLR4) in COCs, activities of intracellular signaling protein p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-${\kappa}B$); and the concentrations of interleukin (IL)-$1{\beta}$, tumor necrosis factor (TNF)-${\alpha}$, and IL-6. Furthermore, we determined the effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes. Results: The results revealed that LPS treatment significantly elevated TLR4 mRNA and protein expression levels in COCs. Exposure of COCs to LPS also resulted in a marked increase in activity of the intracellular signaling protein p-p38 MAPK and NF-${\kappa}B$. Furthermore, oocytes cultured in maturation medium containing LPS had significantly higher concentrations of the proinflammatory cytokines IL-$1{\beta}$, TNF-${\alpha}$, and IL-6. LPS exposure significantly decreased the first polar body extrusion rate. The cytoplasmic maturation, characterized by polar body extrusion and distribution of peripheral cortical granules, was significantly impaired in LPS-treated oocytes. Moreover, LPS exposure significantly increased intracellular reactive oxygen species levels and the relative mRNA abundance of the antioxidants thioredoxin (Trx), Trx2, and peroxiredoxin 1 in oocytes. Moreover, the early apoptotic rate and the release of cytochrome C were significantly increased in response to LPS. The cleavage, morula, and blastocyst formation rates were significantly lower in parthenogenetically activated oocytes exposed to LPS, while the incidence of apoptotic nuclei in blastocysts was significantly increased. Conclusion: Together, these results provide an underlying mechanism by which LPS impairs maturation potential in bovine oocytes.
Choi, Yoon Seok;Park, Kwang Jae;Yoon, Sang Pil;Chung, Sang Ok;An, Kyoung Ho;Song, Jae Hee
The Korean Journal of Malacology
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v.29
no.1
/
pp.51-63
/
2013
To assess the effect of environmental factors on the sustainability of cultured production shellfish, we investigated the habitat characteristics of tidal flat (Namhae-po in Taean). We measured the physiochemical parameters (temperature, salanity, pH, dissolved oxygen and nutrients) and the geochemical characteristics (chemical oxygen demand, ignition loss, C/N ratio and C/S ratio). Surface sediments were collected from several site of tidal flat to examine the geochemical characteristics of both the benthic environment and heavy metal pollution. The grain size for research area of tidal flat were similar at the ratio of silt and clay in comparison with the other site of it. The C/N ratio was more than 5.0, reflecting the range arising from the mix of marine organism and organic matter. The C/S ratio (about 2.8) showed that survey area had anoxic or sub-anoxic bottom conditions. The enrichment factor (Ef) and index of accumulation rate (Igeo) of the metals showed that those research areas can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted, respectively. Adult surf clam (Mactra veneriformis) density was highest at St. 2 (middle part of the Namhae-po), on the other hand, surf clam spat density was highest at St. 3 (lower part of the Namhae-po). Heavy rain, terrigenous suspended clay with fresh water from neighboring agricultural land, and severe high air temperature during summer could be thought as detrimental causes of spat and adult mortality in Namhae-po tidal flat. We suggested that the growth of shellfish in the tidal flat was effected by the various environmental conditions, so an improvement in the cultured method was needed.
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