• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.391-396
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• 2016

The absorption efficiency of amine $CO_2$ absorbent (KoSol-5) developed by KEPCO research institute was evaluated using a 0.1 MW test bed. The performance of post-combustion technology to capture two tons of $CO_2$ per day from a slipstream of the flue gas from a 500 MW coal-fired power station was first confirmed in Korea. Also the analysis of the absorbent regeneration energy was conducted to suggest the reliable data for the KoSol-5 absorbent performance. And we tested energy reduction effects by improving the absorption tower inter-cooling system. Overall results showed that the $CO_2$ removal rate met the technical guideline ($CO_2$ removal rate : 90%) suggested by IEA-GHG. Also the regeneration energy of the KoSol-5 showed about $3.05GJ/tonCO_2$ which was about 25% reduction in the regeneration energy compared to that of using the commercial absorbent MEA (Monoethanolamine). Based on current experiments, the KoSol-5 absorbent showed high efficiency for $CO_2$ capture. It is expected that the application of KoSol-5 to commercial scale $CO_2$ capture plants could dramatically reduce $CO_2$ capture costs.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.3
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• pp.145-152
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• 2007

In this study, the antioxidative effects of Sueada asparagoides and Salicornia herbacea extracts were investigated. The free radical(1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity($FSC_{50}$) of extract/fractions of Sueada asparagoides was in the order: 100 % ethanol extract(329.33 ${\mu}g/mL$) < 50 % ethanol extract(40.73) < ethylacetate fraction(13.87) < deglycosylated aglycone fraction (7.80). In case of Salicornia herbacea, the free radical scavenging activities of ethylacetate fraction and aglycone fraction were 13.87 and 7.80 ${\mu}g/mL$, respectively. Reactive oxygen species(ROS) scavenging activities($OSC_{50}$) of Sueada asparagoides and Solicornia herbacea extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity of Sueada asparagoides extracts was 50 % ethanol extract($OSC_{50}$, $0.99{\mu}g/mL$) < ethylacetate fraction (0.05) < aglycone fraction (0.03). Aglycone fraction showed the most prominent scavenging activity. In case of Salicornia herbacea, the ROS scavenging activities of ethylacetate fraction and aglycone fraction were 0.10 and 0.20 ${\mu}g/mL$, respectively. The protective effects of extract/fractions of Sueada asparagoides and Salicornia herbacea on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethanol extract(100%) of Sueada asparagoides diminished photohemolysis in a concentration dependent manner($1{\sim}100{\mu}g/mL$). Particularly deglycosylated aglycone fraction exhibited the most prominent celluar protective effect($\tau_{50}$, 310 min at 50 ${\mu}g/mL$). In case of Salicornia herbacea, ethylacetate fraction exhibited more potent protective effect. These results indicate that extract/fractions of Sueada asparagoides can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.316-323
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• 2021

A total of 106 samples (nuts, nut products, oilseeds, oilseed products, seed for beverage products) were simultaneously analyzed with LC/MS/MS method. The tested mycotoxins were aflatoxin (B₁, B₂, G₁, G₂), ochratoxin A, fumonisin (B₁, B₂), and zearalenone. Mycotoxins were detected in 37 of 106 samples (35%), and two or more mycotoxins were simultaneously detected in 9 of 106 samples (8.5%). Aflatoxin, ochratoxin A, fumonisin and zearalenone were detected at the range of 0.08-1.45 ㎍/kg, 17.29 ㎍/kg, 1.16-14.89 ㎍/kg and 0.12-12.69 ㎍/kg, respectively. The results revealed that the most frequently detected mycotoxin was zearalenone (23%), followed by aflatoxin (13%), fumonisin (8%) and ochratoxin A (1%). Detection rates of nuts and oilseeds were 35% and 33%, respectively, and detection rates of their processed foods were 44% and 46%, respectively. The detection rate of mycotoxins was 10% higher in processed foods than in nuts and oilseeds. Mycotoxins are physicochemically stable and can persist during food processing and cooking, making management of mycotoxins in raw materials a concern of high importance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.69-80
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• 2023

This study investigated the differences in barley growth at different growth stages (Dec, Feb, and Apr) and the yield at harvest in three groups (G1, G2, and G3) with different climates. Additionally, we measured meteorological differences between areas during the growing season to determine which factors were related to growth and yield differences. We evaluated the chemical composition of soil and the mineral content in leaves during the heading stages. We also recorded the main constituents, amino acids, and mineral compositions of barley seeds grown in different areas. Tiller number/m² in G1 areas was higher than in G2 and G3 when measured before and after overwintering. However, tiller number/m² and dry aboveground plant parts/m² in G2 and G3 areas were higher than in G1. Regrowth, panicle formation, and heading days in G2 areas occurred slightly later than in G1 and G3. However, there was no difference in chlorophyll content (SPAD value) between groups. The yield in G1 areas was 9~15% less than in G1 and G3. The decrease in yield in G2 areas could be due to lower panicle number, spikelet number, and ripening rate. In addition, the decrease in yield in G2 areas is likely because maximum, minimum, and average daily temperatures during the growing season were lower than those in G1 and G3. However, mineral nutrients in the soil were higher in the G2 area than in G1 and G3. The overall mineral content in plants tended to be higher in G1 areas than in G2 and G3. Mineral content such as Cu, K, Mg, and P in G3 areas and crude protein and most amino acids in G2 areas tended to be relatively low compared to other areas. Thus, the G1 area may be suitable for barley cultivation without adverse impacts on barley yield, main constituents, amino acids, and mineral contents compared to the main producing areas in G3.