• Journal of fish pathology
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• v.19 no.1
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• pp.45-54
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• 2006

The immunogenicity of Edwardsiella tarda was surveyed under two different culture conditions. In SDS-PAGE patterns of the outer membrane proteins (OMPs) extracts of E. tarda, grown under Trypic soy broth (TSB) and TSB supplemented iron chelate 2,2‘-dipyridyl iron-restricted condition, were examined. The results showed that the iron-regulated outer membrane protein (IROMPs) with molecular masses of 68 and 73 kDa were expressed by bacteria grown in iron-chelate TSB.The pathogenicity was examined by intraperitoneal injection with live E. tarda grown under TSB, iron-chelate TSB and iron-supplemented TSB. The result of pathogenicity test showed significantly high mortality in the group of live E. tarda grown under iron-chelate TSB.The effect of formalin killed cell (FKC) of TSB cultured bacteria and 2,2'-dipyridyl FKC (DP-FKC) of cultured bacteria on the iron-chelate TSB on the development of protective immunity in olive flounder was studied. The level of immune response was evaluated with immunized fish at 1, 2, 3 and 4 weeks after immunization. The numbers of specific antibody secreting cells (SASCs) showed significantly increased level at 2 week after immunization in each group. The agglutination titre of immunized fish was significantly high level at 3 weeks after immunization.The level of protection in olive flounder at 1, 2, 3 and 4 weeks after vaccination was examined by intraperitoneal challenge test with live E. tarda.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.1
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• pp.103-106
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• 2008

A broiler experiment was conducted to compare the effects of supplementary iron sources and levels on the iron content of broiler meat. Two hundred and fifty hatched Ross broiler chickens were randomly assigned to 5 dietary treatments. Each treatment had 5 replicates of 10 birds (5 males and 5 females). Birds were housed in raised floor batteries and fed traditional broiler diets ad libitum for 5 weeks. Dietary treatments were as follows: Control, Fe-Met 100 (100 ppm iron as Fe-methionine), Fe-Met 200, $FeSO_4$ 100 (100 ppm iron as $FeSO_4{\cdot}7H_2O$) and $FeSO_4\;200$. There were no significant differences among treatments in parameters related to production performance. Liver contained approximately 10 times more iron than the leg muscle which contained approximately 3 times more iron than either breast muscle or wing muscle. Significant differences in iron content in the broiler meat were observed. In the breast meat, Fe-Met treatments were significantly (p<0.05) higher than other treatments in iron content. In the leg meat, Fe-Met treatments and $FeSO_4\;200$ treatment were significantly higher than the control in iron content. In the wing muscle, Fe-Met 200 treatment was significantly higher than other treatments in iron content. Iron content in the liver was significantly influenced by source and supplementation level of iron. Fe-Met treatments were higher than $FeSO_4$ treatments and 200 ppm treatments were higher than 100 ppm treatments in iron content in the liver. It is concluded that iron-methionine chelate is more efficient than iron sulfate and 200 ppm iron supplementation as Fe-Met is recommended for maximum iron enrichment in broiler meat.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1725-1728
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• 2004

An experiment was conducted to investigate the efficiency of transfer of dietary iron sources to eggs of laying hens. Eighty ISA-Brown laying birds of 30 wk old were housed in 40 cages of 2 birds each. Eight birds in four cages were assigned to one of the following ten treatments: T1; control, T2; 100 ppm iron supplementation with iron-methionine chelate (Fe-Met-100), T3; Fe-Met- 200, T4; Fe-Met-300, T5; 100 ppm iron supplementation with iron sulfate ($FeSO_4$-100), T6; $FeSO_4$-200, T7; $FeSO_4$-300, T8; 100 ppm iron supplementation with Availa-$Fe^{(R)}$ (Availa-Fe-100), T9; Availa-Fe-200 and T10; Availa-Fe-300. Results of 40 d feeding trial showed that there were no consistent responses in laying performance by source and level of iron supplementation. However, eggshell strength and color were improved by Fe supplementation. Egg iron content was maximized at 10-15 days after feeding supplemental Fe. Fe- Met was the most effective source in enriching Fe of eggs followed by Availa-Fe and $FeSO_4$. Increasing supplementary Fe level more than 100 ppm was not effective in Fe-Met and Availa-Fe treatments. Average Fe enrichment of 18% was achieved after feeding Fe-Met-100 for 15 d. In conclusion, enrichment of Fe in egg could be effectively achieved by supplementation of Fe-Met-100 for 15 d.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.10
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• pp.1501-1505
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• 2008

A broiler experiment was conducted to compare the effects of duration and level of iron-methionine chelate (Fe-Met) supplementation on the iron, copper (Cu) and zinc (Zn) content of broiler meat. Two hundred and fifty hatched Ross broiler chickens were randomly assigned to 5 dietary treatments. Each treatment had 5 replicates of 10 birds (5 males and 5 females) each. Birds were housed in raised floor batteries and fed traditional broiler diets ad libitum for 5 weeks. Dietary treatments were as follows: Control and two levels of Fe-Met (100 or 200 ppm in Fe) supplemented for either the whole period (0-5 wk) or grower period (4-5 wk). Production performance was not significantly affected by treatments. Iron content in the muscles (breast, leg and wing) and organs (liver and spleen) were significantly (p<0.05) increased as the level and duration of Fe-Met supplementation increased. The highest concentration of iron was shown in Fe-Met 200 fed for the whole period. Liver contained the highest amount of iron followed by spleen, leg muscle, wing muscle and breast muscle. Supplementation of Fe-Met 200 for the grower period resulted in higher iron concentration in liver and spleen than supplementation of Fe-Met 100 for the whole period. However, the same treatment resulted in lower iron concentration in muscles (breast, leg and wing) than the treatment of Fe-Met 100 for the whole period. In order to achieve the highest iron enrichment in the muscles, Fe-Met should be supplemented at 200 ppm in Fe for the whole period (5 wks). Fe-Met supplementation increased copper concentration in all muscles and organs except wing muscle. Zinc concentration decreased in breast and wing muscle but tended to increase in leg muscle, liver and spleen by Fe-Met 200 supplementation. Color of muscle was not significantly affected by Fe-Met treatments. However, redness of leg and breast muscle, and yellowness of leg and breast muscle tended to increase by supplementation of Fe-Met for the whole period. It was concluded that iron content of broiler meat can be effectively enriched by supplementation of 200 ppm of Fe as Fe-Met for 5 wks.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.51-56
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• 2019

$H_2S$ is a detrimental impurity that must be removed for upgrading biogas to biomethane. This study investigates an economic method to mitigate $H_2S$ content, combining scrubbing and aeration. The desulfurization experiments were performed in a laboratory apparatus using EDTA-Fe or landfill leachate as the catalyst and metered mixture of 50-52% (v/v) $CH_4$, 32-33% (v/v) $CO_2$ and 500-1,000 ppmv $H_2S$ balanced by $N_2$ using the C city landfill gas. Dissolved iron concentration in the liquid medium significantly affected the oxidation efficiency of sulfide. Iron components in landfill leachate, which would be available in a biogas/landfill gas utilization facility, was compatible with an external iron chelate. More than 70% of $H_2S$ was removed in a contact time of 9 seconds at iron levels at or over 28 mM. The scrubbing-aeration process would be a feasible and easy-to-operate technology for biogas purification.

• Applied Chemistry for Engineering
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• v.35 no.3
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• pp.255-259
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• 2024

In this study, an aqueous-based redox flow battery (RFB) was constructed using tungstosilic acid (TSA), which is a kind of polyoxometalate, as the negative electrode active material and iron chloride (FeCl3) as the positive electrode active material in a sulfuric acid (H₂SO₄) supporting electrolyte. As a result of the cell's performance, it exhibited capacity fading and low energy efficiency. To address these issues, malic acid (MA), an organic additive, was introduced to the positive electrode active material and then tested for electrochemical properties and single cell performance. The malic acid in the iron chloride aqueous solution is working as a chelate agent, and two carboxyl groups are effectively coordinated with iron ions. It was found that MA reduced the electrolyte resistance of the positive electrode active material, leading to chemical stabilization and an increase in capacity and energy efficiency.

• Journal of Microbiology and Biotechnology
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• v.34 no.8
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• pp.1551-1562
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• 2024

Fungi employ diverse mechanisms for iron uptake to ensure proliferation and survival in iron-limited environments. Siderophores are secondary metabolite small molecules with a high affinity specifically for ferric iron; these molecules play an essential role in iron acquisition in fungi and significantly influence fungal physiology and virulence. Fungal siderophores, which are primarily hydroxamate types, are synthesized via non-ribosomal peptide synthetases (NRPS) or NRPS-independent pathways. Following synthesis, siderophores are excreted, chelate iron, and are transported into the cell by specific cell membrane transporters. In several human pathogenic fungi, siderophores are pivotal for virulence, as inhibition of their synthesis or transport significantly reduces disease in murine models of infection. This review briefly highlights siderophore biosynthesis and transport mechanisms in fungal pathogens as well the model fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe. Understanding siderophore biosynthesis and transport in pathogenic fungi provides valuable insights into fungal biology and illuminates potential therapeutic targets for combating fungal infections.

• Journal of Life Science
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• v.27 no.4
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• pp.390-397
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• 2017

Iron (Fe) is an important micronutrient for the health and growth of plants. Iron is usually provided by fertilizers, and iron-chelate fertilizers are well absorbed by plants. This study presents the plant growth-promoting effects of a new functional iron fertilizer, Fe-chelating crab shell powder (FCSP), which is generated from the chelation of Fe ions with crab shell powder. Iron chelate was derived from spent pickling liquor, which is rich in reductive iron, iron(II) oxide. To analyze the effects of FCSP on plant growth, we treated lettuce with several concentrations of FCSP in both lab- and field-scale experiments. In the lab-scale test, the treatment of 50 ppm of FCSP highly promoted growth and resulted in increases in the size, weight, number and chlorophylls content of leaves of plants compared to the treatment of crab shell powder. Fifty ppm of FCSP also increased the size and weight of leaves up to 2 times compared to the application of chemical fertilizer and/or compost in field conditions. In addition, the FCSP treatment resulted in the highest ion uptake of Fe in lettuce leaves. Moreover, FCSP led to increases in the amounts of Fe, Ca, available phosphorus and organic matter in treated soil, indicating that soil quality was improved. Taken together, our results demonstrate that FCSP promotes lettuce growth via enhancement of Fe availability and improves soil quality. Therefore, FCSP can be utilized as a new functional iron fertilizer.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.652-655
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• 2013

Diverse p-terphenyl compounds, named curtisians, have been isolated from the fungus Paxillus curtisii, and degradation of wood by this fungus is thought to be progressed by iron chelation of p-terphenyl curtisians. In this study, the iron chelation ability of p-terphenyls has been proved by chrome azurol S (CAS) assay, reducing power, and UV-visible spectroscopic analyses. The catechol moiety of p-terphenyl is an essential factor for the potent iron chelation ability, and thus deacylated curtisian with a tetrahydroxyl moiety in the central ring of p-terphenyl is more effective than acylated curtisians.

• Korean Journal of Acupuncture
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• v.22 no.4
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• pp.57-65
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• 2005

Objectives : Circium japonicum is a pharmacologically active used in traditional Korean medicine. An aqua-acupuncture solution of the Circium japonicum was assessed to determine the mechanism of its antioxidant activity. Materials : Circium japonicum was obtained from a Dongguk Korean Medicine Hospital (Kyung-ju, Kyungbuk). The freeze-dry powder was collected (yield 5.1%) for the aqua-acupuncture solution. Scavenging activity on DPPH free radicals by the Circium japonicum aqua-acupuncture solution (CJAS) was assessed according to the method followed by Gyamfi et al.. and then scavenging activity orl superoxide radicals $(O_2^-{\cdot})$ was assessed by the method described by Gotoh et al. with slight modification. Deoxyribose assay to determine the rate constant for the reactions between either antioxidants and hydroxyl radicals or antioxidants and iron ions. We tested by; (1) Non-site-specific scavenging assay (hydroxyl radicals, OH), (2) Site-specific scavenging assay (chelate iron ions), and (3) Pro-oxidant effect of the CJAS on iron dependent hydroxyl radical generation. Finally, we determined hydroxyl radical-mediated DNA nicking formation. Conclusion : Our study demonstrated that CJAS has antioxidant activities and we investigated the potential effectiveness of CJAS in preventing oxidative stress-mediated disease further.