• Food Science of Animal Resources
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• v.36 no.1
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• pp.37-43
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• 2016

Cardiovascular and cerebrovascular diseases seriously harm human health, and Bifidobacterium is the most beneficial probiotic in the gastrointestinal tract of humans. This work aimed to screen cholesterol-lowering Bifidobacterium from Guizhou Xiang Pig and evaluate its tolerance to oxygen, acid, and bile. Twenty-seven aerotolerant strains with similar colony to Bifidobacterium were isolated through incubation at 37℃ in 20% (v/v) CO₂-80% (v/v) atmospheric air by using Mupirocin lithium modified MRS agar medium, modified PTYG with added CaCO₃, and modified PTYG supplemented with X-gal. Ten strains with cholesterol-lowering rates above 20% (w/w) were used for further screening. The selected strains’ tolerance to acid and bile was then determined. A combination of colony and cell morphology, physiological, and biochemical experiments, as well as 16S rRNA gene-sequence analysis, was performed. Results suggested that BZ25 with excellent characteristics of high cholesterol-removal rate of 36.32% (w/w), as well as tolerance to acid and bile, was identified as Bifidobacterium animalis subsp. lactis. To further evaluate Bifidobacterium BZ25’s growth characteristic and tolerance to oxygen, culture experiments were performed in liquid medium and an agar plate. Findings suggested that BZ25 grew well both in environmental 20% (v/v) CO₂-80% (v/v) atmospheric air and in 100% atmospheric air because BZ25 reached an absorbance of 1.185 at 600 nm in 100% atmospheric air. Moreover, BZ25 was aerotolerant and can grow in an agar medium under the environmental condition of 100% atmospheric air. This study can lay a preliminary foundation for the potential industrial applications of BZ25.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.661-666
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• 2009

The heat tolerance and the inactivation kinetics of peroxidase (POD) and polyphenol oxidase (PPO) in pineapples (Ananas comosus) were studied in the temperature range $45-95^{\circ}C$. The kinetic parameters, such as deactivation rate constant (k), activation energy ($E_a$), and decimal reduction rate (D) of the thermal inactivation process, were determined. POD in pineapples showed biphasic inactivation behavior at temperatures range $45-75^{\circ}C$ but was monophasic at $85-95^{\circ}C$. This indicate that POD has 2 isozymes, namely heat labile and heat resistant, with $E_a$ of 68.79 and 93.23 kJ/mol, respectively. On the other hand, the heat denaturation of pineapple PPO could be described as simple monophasic first-order behavior with $E_a$ of 80.15 kJ/mol. Thus, the results of this study is useful in blanching technology where it shows a shortened time with higher temperature can be applied. The determination of the heat tolerance and inactivation POD and PPO, at different temperature range as done in the present work, was very important to improve the blanching process. This also will help to optimize the pineapple canning process which is one of the most important food industries in many tropical regions.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.441-448
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• 2008

The purpose of this study was to analyze chemical water quality, fish trophic guilds, tolerance indicators, and fish community conditions in the Gap Stream and to compare the stream conditions between the unimpacted site and impacted site. This study was conducted in the physically stable season (May 2008) to minimize physical impacts such as flow and hydrological disturbance, and applied the study in the Gap Stream with two sites of unimpacted upstream site (Unim-S), mainly surrounded by forested area and impacted site (Im-S), influenced by the wastewater disposal plants and industrial complex in the urban region. Chemical data analysis showed that the degree of organic matter pollution, based on BOD, and COD, was $2{\sim}3$ fold greater in the Im-S than the Unim-S, and that TP, as eutrophication indicators, was 4.7 fold greater in the Im-S. Also, $NH_3-N$ was in 8.2 fold greater in the Im-S ($6.25\;mg\;L^{-1}$) than the Unim-S ($0.76\;mg\;L^{-1}$), indicating a massive influence of wastewater from the disposal plant. Similar results were found in other chemical parameters. Thus, chemical impacts in the Im-S were evident, compared to the unimpacted site. Evaluations of tolerant indicator species indicated that sensitive species were dominant in the Unim-S (23.9%) and tolerant species were dominant (97.8%) in the Im-S. Condition factor (CF) was averaged 0.95 ($0.68{\sim}1.18$) in the Unim-S and 1.08 ($0.93{\sim}1.22$) in the Im-S. Fish community in the Unim-S and Im-S was categorized as Zacco-community and Hemibarbus-community, respectively, and the community diversity index (H') was significantly (p<0.05) higher in the Unim-S (0.810) than the Im-S (0.466). Overall, our results suggest that the comparison approach of various chemical and ecological indicators provide important information in identifying multiple stressors in the stream ecosystems.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.909-915
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• 2022

In this paper, a robot automation technology for chemical tank lorry unloading is presented. Handling chemical coupler between tank lorry and ACQC system may be hazardous or toxic to human operators, therefore robot automation is essential. Due to tight tolerance between couplers, even small pose error may result in very large internal force. In order to resolve the problem, compliance between male and female couplers should be introduced with 6-axis compliance device with F/T sensing. The proposed robot automation system consists of a collaborative robot, 6-ax is compliance device with F/T sensing, linear gripper, and robot vision. The position/force control algorithm and experimental results for assembling chemical couplers are presented.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2283-2286
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• 2009

A convenient route for the preparation of water soluble polythiophenes is described. Reactions involving highly active zinc metal show unique properties, viz. tolerance of the ester group and regioselectivity to the thiophene ring. Poly [3-(ethyl-n-alkanoate)thiophene-2,5-diyl]s, poly [3-(n-carboxyalkyl)thiophene-2,5-diyl]s, and poly [3-(potassium- n-alkanoate)thiophene-2,5-diyl]s were easily prepared by utilizing highly active zinc.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.39-43
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• 2014

A facile transformation of aryl aldehydes to benzyl iodides through one-pot reductive iodination is reported. This protocol displays remarkable functional group tolerance and the title compound was obtained in good to excellent yield.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.324-329
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• 2020

Reed (Phragmites spp.) is a rhizomatous plant of the Poaceae family and is known as high tolerant plant to heavy metal contaminants. This plant is widely recognized as a Cd root-accumulator, but improved heavy metal tolerance and uptake capacity are still required for phytoremediation efficiency. To enhance capacity of hyperaccumulator plants, ethyl methane sulfonate (EMS) as chemical mutagen has been introduced and applied to remediation approaches. This study aimed to select EMS-mutagenized reeds representing high Cd resistance and large biomass and to investigate their ability of Cd accumulation. After 6 months cultivation of M₂ mutant reeds under Cd stress conditions (up to 1,500 µM), we discovered seven mutant individuals that showed good performances like survivorship, vitality, and high accumulation of Cd, particularly in their roots. Compared to wild type (WT) reeds as control, on average, dry weight of mutant type (MT) reeds was larger by 2 and 1.5 times in roots and shoots, respectively. In addition, these mutant plants accumulated 6 times more Cd, mostly in the roots. In particular, MT8 reeds showed the greatest ability to accumulate Cd. These results suggest that EMS mutagenesis could generate hyperaccumulator plants with enhanced Cd tolerance and biomass, thereby contributing to improvement of phytoremediation efficiency in Cd-contaminated soil or wastewater. Further studies should focus on identifying Cd tolerance mechanisms of such EMS-mutagenized plants, developing techniques for its biomass production, and investigating the practical potential of the EMS mutants for phytoremediation.

• Korean Journal of Environmental Biology
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• v.37 no.1
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• pp.8-18
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• 2019

The objectives of this study were to analyze the influence of chemical water quality on fish guilds, pollution tolerance and the multi-metric ecological health, based on the Fish Assessment Index (FAI) in the main stream of Mangyeong River between 2009-2016. The quality of water with specific conductivity, TP, and $NH_4-N$ got worse dramatically in the down region. During the study, a total of 50 species were collected and the most dominant species was Zacco platypus. Also known as tolerant species, accounted 22.9% of the total abundances, thus indicating a trophic degradation. The downstream region (S5) had the highest number of fish external abnormalities, indicating a degradation of ecological health, based on the fish assemblages. Pearson correlation analysis indicated that relative abundance of tolerant fish species and omnivore fish species had a significant positive correlation(r>0.30, p<0.05) with values of BOD, conductivity and $NH_4-N$. Whereas, the relative abundance of the sensitive species and insectivore species had a significant negative relations (r<-0.30, p<0.001) with the parameters. The mean obtained from the multi-metric fish model, based on the FAI of all sites was 47 (n=40). This indicated a "fair condition" in the ecological health, and the downstream regions (S3-S5) were judged as "bad condition", indicating an influence of the chemical degradation on the ecological health.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.54-63
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• 2015

Streptomyces spp. isolated from turfgrass rhizosphere and tested for their response to large-patch control fungicides. The tested fungicides were actually used in golf course or turfgrass cultivation to prevent large-patch disease. Tolerance to 3 triazole group of the strains was the highest to the PR fungicide, and following the SR fungicide, whereas the isolated strains were no tolerance to HR fungicide. Tolerances to three kind of Strobilurin group were similar for the all of the tested Streptomyces spp.. Growth and sporulation of the all strain was normal in CB and AP fungicide treatments. However no spore formulated in double concentration. Strains, tolerance to acetanilide fungicides, appeared that KT fungicide tolerance was higher than MK fungicide. The selected strains showed strong tolerance against AT fungicide but have no tolerance to ATR fungicides. In conclusion, the bacterial strains showed tolerance against 1 carbamate, 1 organophosphate and 1 cyanopyrrole group, while have no tolerance against two mixture formulations (1 Quinone + Strobilurin and 1 Imidazole + Triazole).

• Journal of Ginseng Research
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• v.23 no.2 s.54
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• pp.61-66
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• 1999

Experiments were carried out to examine the rusty tolerance in 61 inbred lines of ginseng cultivated in field, and chemical components were analyzed to clarify the difference between healthy and rusty ginseng roots. Among them, 10 lines showed rusty tolerance (RT) while 10 lines showed rusty sensitivity (RS). The content of phenolic compound in RT was lower than that in RS in cortex, epidermis and branch & fine roots, but it was not difference between RT and RS in stele. The contents of K, Ca, Na in RT were lower than RS in cortex, and the content of Mg, Fe, Na, Mn, AI, Si in RT were lower than RS in epidermis, and the content of Fe in RT were lower than RS in branch & fine roots, but mineral contents were not difference between RT and RS in stele. The content of phenolic compound in healthy cortex was lower than that in rusty cortex in same 6-year roots, but the mineral contents were not difference between healthy and rusty cortex in same 6-year roots. In root of seedlings, the contents of phenolic compound, K and Na in RT were lower than RS. It was suggested that the contents of phenolic compound, K and Na might be marker to select rusty tolerance ginseng lines.