• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.44-49
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• 2003

Effects of supplementation with ruminal epithelial cells on fiber-degrading activity and cell growth of Ruminococcus albus (R. albus, strain 7) was tested using a basal substrate of rice straw and formulated concentrate. Cultures of R. albus alone and R. albus with rumen protozoa were grown at $39^{\circ}C$ for 48 h with an 8.4% crude protein (CP) substrate, 33% of the CP supplemented with either ruminal epithelial cells or defatted soybean meal. The ruminal epithelial cells had lower amounts of rumen soluble and degradable protein fractions as compared to defatted soybean meal, as determined by an enzymatic method, and the same was found with amino acid composition of protein hydrolysates. Ruminal epithelial cells were directly utilized by the R. albus, and resulted in greater growth of cell-wall free bacteria compared to defatted soybean meal. The effect of epithelial cells on bacterial growth was enhanced by the presence of rumen protozoa. In consistency with cultures of R. albus and R. albus with rumen protozoa, fermentative parameters such as dry matter degradability and total volatile fatty acid did not differ between supplementation with ruminal epithelial cells or defatted soybean meal.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.2
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• pp.29-36
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• 2008

In order to give pulp surfaces anti-bacterial functionality and photo-catalytic deodorant ability, functional pulps was made using a surface modification method with Ag nano-colloidal solution and $TiO_2$ filler. Hygiene paper was made with the specially modified pulp, and anti-bacterial and deodorant tests were carried out. The Ag nano-colloidal solution was coated on the surface of the pulp using the high pressurized gas phase squirt through the spray nozzle mounted on the hybridization system. The surface modified functional pulp was hybridized with the optimum ratio of $TiO_2$(fine particle) to pulp(core particle) under the condition of $6,000{\sim}10,000$ rpm for $3{\sim}7$ minutes in the system. The anti-bacterial functionality of the hygiene paper was confirmed by the halo test in which the formation of the clear zone around the hygiene paper sample was observed. The inhibition growth test using MIC bioscreen C showed the inhibition growth effect of the bacteria as the reaction time was increased. The photo-catalytic effect measurement of the $TiO_2$ for 4 hours of the reaction showed $50{\sim}60%$ of decomposition rate, reaching over 60% for 5 hours of the reaction.

• The Korean Journal of Emergency Medical Services
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• v.20 no.3
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• pp.49-56
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• 2016

Purpose: The purpose of this study was to investigate the effect of a pathogenic bacteria filtration instrument for infection prevention during mouth-to-mouth ventilation. Methods: Two kinds of face shields were used for the study. One rescuer blew the filter through a bag valve mask and the filter was then cultured for bacteria. The mask was tested both on the front and back side. Results: Two kinds of face shields including the KF shield and CM shield were tested. The KF shield has received national certification and it prevented transmission of bacterial infection but the CM shield showed the opposite result and did not prevent bacterial transmission. Pathogenic bacteria were found on the back of the CM shield. Conclusion: A certified face shield is very important to prevent bacterial transmission. Face shields should be demonstrated and used by paramedic students.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.561-565
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• 2005

In this study, we attempted to assess the effects of lactate and com steep liquor (CSL) on the production of bacterial cellulose (BC) by Gluconacetobacter persimmonis $KJ145^T$. The optimal condition for the production of BC was a lactate concentration of 1% (w/v) and a CSL concentration of 10% (w/v). Under these optimal conditions, 6 days of fermentation produced 6.90 g/L of BC. Both the BC production yield and cell growth increased continuously until the 20th day of fermentation, by which time 17.0 g/L had been produced. In a static culture trial, in which plastic containers were used as fermentation chambers for 6 days of fermentation, the BC production yield in the group initially cultured with 500 mL medium was higher than that of the 750 and 1000 mL media. In addition, the texture of the BC was examined according to its post-treatment in order to determine conditions for optimal textural characteristics. The strength, hardness, and other characteristics of the BC were negatively correlated with sucrose concentration, but were largely positively correlated with NaCl concentration. With regards to the effect of pH on textural change, BC strength and hardness were elevated at pH 2 and 8 but reduced at pH 4 and 6, indicating that the texture of the BC is extremely sensitive to treatment conditions.

• Mycobiology
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• v.46 no.3
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• pp.287-295
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• 2018

In this study, we evaluated the effect of different temperatures (10, 20, 30, and $40^{\circ}C$) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1473-1483
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• 2014

Reports of herbicide resistance events are proliferating worldwide, leading to new cultivation strategies using combinations of pre-emergence and post-emergence herbicides. We analyzed the impact during a one-year cultivation cycle of several herbicide combinations on the rhizobacterial community of glyphosate-tolerant Bt-maize and compared them to those of the untreated or glyphosate-treated soils. Samples were analyzed using pyrosequencing of the V6 hypervariable region of the 16S rRNA gene. The sequences obtained were subjected to taxonomic, taxonomy-independent, and phylogeny-based diversity studies, followed by a statistical analysis using principal components analysis and hierarchical clustering with jackknife statistical validation. The resilience of the microbial communities was analyzed by comparing their relative composition at the end of the cultivation cycle. The bacterial communites from soil subjected to a combined treatment with mesotrione plus s-metolachlor followed by glyphosate were not statistically different from those treated with glyphosate or the untreated ones. The use of acetochlor plus terbuthylazine followed by glyphosate, and the use of aclonifen plus isoxaflutole followed by mesotrione clearly affected the resilience of their corresponding bacterial communities. The treatment with pethoxamid followed by glyphosate resulted in an intermediate effect. The use of glyphosate alone seems to be the less aggressive one for bacterial communities. Should a combined treatment be needed, the combination of mesotrione and s-metolachlor shows the next best final resilience. Our results show the relevance of comparative rhizobacterial community studies when novel combined herbicide treatments are deemed necessary to control weed growth.

• Advances in Traditional Medicine
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• v.6 no.2
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• pp.134-143
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• 2006

The capacities of bacterial DNA, extracted from Salmonella typhimurium, and lipopolysaccharide (LPS), extracted from Salmonella minnesota, to activate mouse peritoneal macrophages in vitro were compared. Activation was assessed by estimating e levels of 3 cytokines, IL-10, IL-12, and $IL-1{\beta}$, at time intervals of 3, 6, 9, and 24 h after addition of LPS and/or DNA to macrophage cultures. Cytokine levels in culture supernatants were determined by enzyme-linked immunosorbent assay (ELISA) and cytokine mRNA levels were estimated based on band intensity in cultured cells by reverse transcriptase-polymerase chain reaction (RT-PCR). Results obtained demonstrated the ability of DNA and LPS to elicit increased production of all 3 cytokines as compared to controls. In the amount tested, LPS appeared to be a more potent inducer of IL-12, and $IL-1{\beta}$, whereas DNA induced higher levels of IL-10. DNA and LPS, used in combination, exhibited neither an additive nor a synergistic effect. Rather, an antagonist effect appeared to occur. RT-PCR results correlated well with ELISA.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.3
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• pp.53-59
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• 2018

When manufacturing self-healing concrete using bacteria, nutrients are added to increase the activity of the bacteria. Although many researches have focused on the effects of nutrients containing bacterial healing agent on concrete, few have studied the effects of sole nutrient on self-healing of cement composites. Bacterial nutrients, like commercial chemical admixtures, affect hydration characteristics such as flow, setting, hydration heat, mechanical strength of cement composites and also affect the self healing of cement composites by hydration of unhydrated particles. In this study, effect of the four nutrient commonly used in the existing literature on the hydration characteristics of cement composites by its addition was investigated. Flow, setting time, hydration heat, compressive strength have studied for each nutrients added by 1.5% and 3% of cement weight. Experimental results shows that urea and calcium-nitrate can be used up to 3% without significant detrimental effect on cement composites. Addition of calcium-lactate up to 1.5% show better compressive strength than control, but addition of 3% show almost non-hydration. Yeast extract shows detrimental effects on the composites regardless of the amount added.

• Journal of Environmental Science International
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• v.30 no.12
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• pp.1093-1100
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• 2021

The present study investigated the effect of ammonia load on microbial communities in mesophilic anaerobic digestion of propionic acid. A laboratory-scale continuous anaerobic digester treating propionic acid as a sole organic substrate was operated under non-inhibitory condition and inhibitory conditions with ammonia (1.5 g and 3.5 g ammonia-N/L, respectively), and bacterial and archaeal communities in the steady states of each ammonia condition were analyzed using high-throughput sequencing. Thirteen bacterial families were detected as abundant bacterial groups in mesophilic anaerobic digestion of propionic acid. Increase in ammonia concentration resulted in significant shifts in microbial community structures. Syntorophobacter, Pelotomaculum, and Thermovigra were determined as the dominant groups of (potential) propionate oxidizing bacteria in the non-inhibitory condition, whereas Cryptanaerobacter and Aminobacterium were the dominant groups of (potential) propionate oxidizing bacteria in the ammonia-inhibitory condition. Methanoculleus and Methanosaeta were the dominant methanogens. Acetate-oxidation coupled with hydrogenotrophic methanogenesis might be enhanced with increases in the relative abundances of Methanoculleus and Tepidanaerobacter acetatoxydans under the ammonia-inhibitory condition. The results of the present study could be a valuable reference for microbial management of anaerobic digestion systems that are exposed to ammonia inhibition and propionic acid accumulation.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.4
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• pp.229-238
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• 2022

Severe bacterial infections are frequently accompanied by depressed neutrophil functions. Thus, agents that increase the microbicidal activity of neutrophils could add to a direct antimicrobial therapy. Lysophosphatidylcholine augments neutrophil bactericidal activity via the glycine (Gly)/glycine receptor (GlyR) α2/TRPM2/p38 mitogen-activated protein kinase (MAPK) pathway. However, the direct effect of glycine on neutrophil bactericidal activity was not reported. In this study, the effect of glycine on neutrophil bactericidal activity was examined. Glycine augmented bactericidal activity of human neutrophils (EC₅₀ = 238 μM) in a strychnine (a GlyR antagonist)-sensitive manner. Glycine augmented bacterial clearance in mice, which was also blocked by strychnine (0.4 mg/kg, s.c.). Glycine enhanced NADPH oxidase-mediated reactive oxygen species (ROS) production and TRPM2-mediated [Ca²⁺]_i increase in neutrophils that had taken up E. coli. Glycine augmented Lucifer yellow uptake (fluid-phase pinocytosis) and azurophil granule-phagosome fusion in neutrophils that had taken up E. coli in an SB203580 (a p38 MAPK inhibitor)-sensitive manner. These findings indicate that glycine augments neutrophil microbicidal activity by enhancing azurophil granule-phagosome fusion via the GlyRα2/ROS/calcium/p38 MAPK pathway. We suggest that glycine could be a useful agent for increasing neutrophil bacterial clearance.