• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.532-541
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• 2010

Peroxidase-like activity of Vitreoscilla hemoglobin (VHb) has been recently disclosed. To maximize such activity, two catalytically conserved residues (histidine and arginine) found in the distal pocket of peroxidases have successfully been introduced into that of the VHb. A 15-fold increase in catalytic constant ($k_{cat}$) was obtained in P54R variant,which was presumably attributable to the lower rigidity and higher hydrophilicity of the distal cavity arising from substitution of proline to arginine. None of the modifications altered the affinity towards either $H_2O_2$ or ABTS substrate. Spectroscopic studies revealed that VHb variants harboring the T29H mutation apparently demonstrated a spectral shift in both ferric and ferrous forms (406-408 to 411 nm, and 432 to 424-425 nm, respectively). All VHb proteins in the ferrous state had a $\lambda_{soret}$ peak at ~419 nm following the carbon monoxide (CO) binding. Expression of the P54R mutant mediated the downregulation of iron superoxide dismutase (FeSOD) as identified by two-dimensional gel electrophoresis (2-DE) and peptide mass fingerprinting (PMF). According to the high peroxidase activity of P54R, it could effectively eliminate autoxidation-derived $H_2O_2$, which is a cause of heme degradation and iron release. This decreased the iron availability and consequently reduced the formation of the $Fe^{2+}$-ferric uptake regulator protein ($Fe^{2+}$-Fur), an inducer of FeSOD expression.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1485-1491
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• 2005

This experiment was conducted to investigate the effects of iron from an amino acid complex (Availa-$Fe^{\circledR}$) on the iron status of neonatal and suckling piglets. A total of 24 gestating sows (Landrace${\times}$Large White) were randomly allocated to three dietary treatments. The control diet contained 80 mg $kg^{-1}$ Fe from ferrous sulfate heptahydrate ($FeSO_4$.$7H_2O$), while the two experimental diets were supplemented with an additional 120 mg $kg^{-1}$ Fe from Availa-$Fe^{(R)}$ or $FeSO_4$.$7H_2O$, respectively. The lactating sows remained the same iron treatments as gestating sows, while neonatal piglets of 24 litters born from the above sows were allotted to another three treatments. Piglets from the sows of the control treatment were fed basal diet with no supplemental Fe as control treatment, but were injected with 100 mg Fe as Fe dextran at birth. Piglets from the sows of Availa-$Fe^{(R)}$ or $FeSO_4$.$7H_2O$ treatments were supplemented with 120 mg $kg^{-1}$ iron from Availa-$Fe^{(R)}$ or $FeSO_4$.$7H_2O$, respectively. The total born alive and weaned, and the average piglets weight at birth and at weaning were not significantly affected by the sow' dietary treatments (p>0.05). Iron from Availa-$Fe^{(R)}$ did not demonstrate a statistically significant improvement in hemoglobin concentration, hematocrit and plasma iron of sows on day 90 and 105 of pregnancy and the milk iron of sows during lactation (p>0.05). Neonatal piglets in the Availa-$Fe^{(R)}$ treatment had a significantly higher hemoglobin concentration (p<0.05) and higher hematocrit and plasma iron (p>0.05) than those in the other two treatments, respectively. The hemoglobin of suckling piglets in the Availa-$Fe^{(R)}$ treatment was higher than that of piglets in $FeSO_4$.$7H_2O$ treatment on day 28 (p<0.05). The total iron binding capacity of piglets in Availa-$Fe^{(R)}$ treatment was lower than that of piglets in the control and $FeSO_4$.$7H_2O$ treatment on day 14 (p<0.05), but there was not a statistically significant difference among three treatments on day 28 (p>0.05). However, the hemoglobin and hematocrit of suckling piglets injected with Fe were higher than those of piglets in the other two treatments (p<0.05). This study indicated that the addition of 120 mg $kg^{-1}$ iron from amino acid complex into the diets improved iron status of neonatal and nursing piglets more effectively than the addition of 120 mg $kg^{-1}$ iron from $FeSO_4$.$7H_2O$, however, this improvement of the organic Fe was not sufficient to replace the Fe injection for prevention of iron-deficiency anemia.

• Korean Chemical Engineering Research
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• v.47 no.2
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• pp.190-194
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• 2009

In this study sodium dodecyl sulfate (SDS), which was anionic surfactant, was added for forming micelles to remove iron ion that could be contained with small amount in industrial water. Then aggregates binding between iron ions and micelles were rejected by a ceramic microfiltration membrane. As result of SDS concentration effect on removal rates of iron and SDS in modified iron solution, the removal rate of iron was the highest value of 92.26% and the removal rate of SDS was 61.10% a little higher than the result of calcium ion at 8 mM which was CMC (Critical micelle concentration) of SDS. As final resistance of membrane fouling $R_f$ increased the more at the higher SDS concentration, it showed the highest value at 4 mM and the lowest at 10 mM of SDS. The final permeate flux $J_{180}$ had the highest value and the largest total permeate volume could be finally acquired at SDS 10 mM. In case of CMC 8 mM, low $R_f$ was shown as same as that of 10 mM until 80 minutes of operation, and tended to increase dramatically to 120 minutes and increase slowly again until 180 minutes.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.102-107
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• 1983

The effects of saponin, one of major components (Panax ginseng C.A. Meyer), on the growth of E. coli K-12 and the formation of siderphore was observed The following results were obtained. 1. When E. coli was grown on medium containing 1${\times}$10-5%-11${\times}$10-1% of the saponin, the rate of growth was stimulated at 10-1% of the saponin significantly compared to that of control. 2. When E. coli K-12 was grown on medium containing 1${\times}$10-1% of the saponin, the amount of siderphore was two times as much as the control. 3. The growth of E. coli was observed to be dependent on the concentration of siderophore when siderophore was added to medium. 4. The effect of saponin on the formation of siderophore in vitro was observed to reach maximum at 1${\times}$10-3% of the saponin. Such results suggest that the growth rate of E. coli K-12 could be enhanced by ginseng saponin fraction through stimulation of siderphore formation. We have described the fast growth of E. coli, K-12 and B. subtilis, rapid uptake of 14C-glucose, and high level of other metabolites such as lipids and proteins of E. coli, and B. subtilis in medium containing saponing fraction compared to that of microorganisms without saponin fraction.1∼3Such differences were claimed to be due to rapid uptake of 14C-glucose by widened periplasmic region throught unknown mechanism in the prescence of saponin fraction in medium3 and have raised a question whether there is another possible factor, siderophore4(Greek for iron bears), since microorganisms must secure a sufficient amount of iron for normal growth. These are known to be synthesized by the cells under iron-deficient condition and in most case, excreted into the medium5, where they can complex and solubilize any iron present there. It is generally believed that these complexes are then taken into the cells presumably by specific transport systems, thus providing iron for cell metabolism. Within the group of enteric bacteria, only three species (E. coli, S. typhimurium, and A. aerogense) have, so far, been studied in a ny detail. The main iron-binding compound produced by these species is enterochelin, and its role in iron transport is now well established. And biosynthesis of enterochelin from 2, 3- dihydroxybenzoate and serine in the prescence of magnesium ions and ATP was reported6. 2, 3-dihydroxybenzoate was also shown to involve isochorismate and 2, 3-dihydro-2, 3-dihydroxybenzoate as intermediate.7∼11 The present paper deals with the effect of ginseng saponin fraction on growth, the level of enterochelin formation in vivo and the conversion of 2, 3-dihydroxybenzoate and serine into entrochelin in vitro, and entrochelin obtained on the growth in relation to possible explanation of ginseng saponin fraction on the rapid growth of E. coli, K-12.

• Journal of Nutrition and Health
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• v.3 no.3
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• pp.149-159
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• 1970

This study is to investigate the status of anemia, especially iron deficiency anemia among pre-school children in rural area in Korea. The survey was conducted in Sang-dae Ri, Yusong Myon, Daedok Gun, Chung Chong Nam-Do from July 30 th to August 12th, 1968. The measurements were done of height, weight, hematologist and biochemical levels on ninety-two pre-school children, 47 male, and 45 female, one to six years of age. Hemoglobin was determined by the method of cyanmethemoglobin and hematocrit by micro hematocrit centrifuge. The determination of serum iron, iron-binding capacity was done by the method of Ramsay using bathophenanthroline and the serum albumin was determined by Biuret Reaction. The results of this study are as follows: 1) 54.4 percent of the pre-school children weighed less than 90 percent of the Korean General Standard Weight level. 2) The average hemoglobin level was $11.0{\pm}1.57gm/100ml$, 38.0 percent of the children were anemic with less than 1.0gm/100ml. Of the anemic children 60 percent were below the Korean General Standard Weight level. 3) 27.5 percent of the pre-school children were found to have below 32 percent of a hematocrit values and 28.0 percent showed less than 33 percent in M.C.H.C. These results showed that the incidence of hypochromic anemia in these pre-school children was high. 4) 37.9 percent of these children had a serum iron level less than $50{\mu}g/100ml\;and\;31.0\;percent\;had\;a\;TIBC\;above\;400{\mu}g$ while 48.3 percent showed a transferrin saturation lower than 15 percent. On the basis of these findings, it is concluded than the cause of this anemia was iron deficiency. 5) In this group there was a little evidence of low total serum protein levels. However, 10.4 percent of the children had a deficient serum albumin level, below 2.80 gm/100ml while 51.7 percent had a low level, less than 3.50gm/100ml, and 34.5 percent of the children had a low level of TIBC, less than $350{\mu}g/100ml$, and considering these facts, it is suggested that some of the anemias have a multiple causes through protein deficiency and repeated chronic infection apart from iron deficiency.

• Biomedical Science Letters
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• v.17 no.3
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• pp.203-209
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• 2011

Magnesium (Mg) plays an essential role in physiological and metabolic reactions. Recently, there has been an increased interest in the role of Mg deficiency, particularly the relationship between serum Mg value and inflammatory response. This study was designed to determine the relationship between serum Mg deficiency with inflammatory response, electrolytes and hematological alteration over long-term periods. Sixteen male Sprague-Dawley rats were divided into two groups: control (n=8), and Mg deficiency group (MgD group, n=8). Chow and normal water (tap water) were regularly provided to the control group and Mg-depleted chow and third distilled water were regularly provided for 60 days to the MgD group. Body weights, Serum Mg, $K^+$, inorganic phosphorus (IP) and total iron binding capacity (TIBC) levels in the MgD group were lower than those of the control group (P<0.05). Granulocyte fraction and MCV, RDW and PDW levels were higher, whereas lymphocyte fraction, erythrocyte, hemoglobin and MCHC levels were lower in the MgD group than in the control group (P<0.05). MCP-1 and TNF-${\alpha}$ levels in the MgD group were greater than those of the control group (P<0.05). In conclusion, the results of the present study suggest that Mg deficiency over a long-term period had not altered total leukocyte concentration in the blood, but had detrimental effects, including disturbances of electrolytes balance, disturbance of iron indices, potential anemia and elevation of pro-inflammatory cytokine. However, further studies should be performed to determine the relationship between serum Mg deficiency and major organ damage or alteration.

• Journal of Dairy Science and Biotechnology
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• v.27 no.1
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• pp.19-28
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• 2009

Lactoferrin was first identified 60 years ago as a "red protein" in bovine milk. Lactoferrin, one of the transferrin family proteins, is an iron-binding glycoprotein found in milk and various mucosal secretions; it is also released from activated neutrophils. Human lactoferrin has a molecular weight of 82.4 kDa and is composed of 702 or 692 amino acid residues. Bovine lactoferrin has a molecular weight of 83.1 kDa and is composed of 689 amino acid residues. Both lactoferrin and transferrin have the ability to bind two $Fe^{3+}$ ions, together with two ${CO_3}^{2-}$ ions with extremely high affinity; these proteins also have the ability to release this iron at low pH levels. The polypeptide chain in lactoferrin is folded into two globular lobes, representing the N-terminal and C-terminal halves. Both lobes have similar folding and 40% sequence identity. This protein is capable of multiple functions as described in various review papers, including antimicrobial, antiviral, antiinflammatory, anticancer, antioxidant, and cell growth-promoting activities. Lactoferrin also exhibits immunomodulating effects and plays an active role in the regulation of myelopoiesis and the inhibition of bacterial translocation.

• BMB Reports
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• v.46 no.3
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• pp.151-156
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• 2013

Phylogenetic and amino acid sequence analysis indicated that rice allene oxide synthase-1 (OsAOS1) is CYP74, and is clearly distinct from CYP74B, C and D subfamilies. Regio- and stereo-chemical analysis revealed the dual substrate specificity of OsAOS1 for (cis,trans)-configurational isomers of 13(S)- and 9(S)-hydroperoxyoctadecadienoic acid. GC-MS analysis showed that OsAOS1 converts 13(S)- and 9(S)-hydroperoxyoctadecadi(tri)enoic acid into their corresponding allene oxide. UV-Visible spectral analysis of native OsAOS1 revealed a Soret maximum at 393 nm, which shifted to 424 nm with several clean isobestic points upon binding of OsAOS1 to imidazole. The spectral shift induced by imidazole correlated with inhibition of OsAOS1 activity, implying that imidazole may coordinate to ferric heme iron, triggering a heme-iron transition from high spin state to low spin state. The implications and significance of a putative type II ligand-induced spin state transition in OsAOS1 are discussed.

• Korean Journal of Materials Research
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• v.15 no.9
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• pp.566-576
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• 2005

This paper describes an ab Initio study on interface energies, misfit strain energies, and electron structures at coherent interfaces Fe(bcc structure)/MCs(NaCl structure M=Ti, Zr, Hf). The interface energies at relaxed interfaces Fe/TiC, Fe/ZrC and Fe/HfC were 0.263, 0.153 and $0.271 J/m^2$, respectively. It was understood that the dependence of interface energy on the type of carbide was closely related to changes of the binding energies between Fe, M and C atoms before and after formation of the interfaces Fe/MCs with the help of the DLP/NNBB (Discrete Lattice Plane/ Nearest Neighbour Broken Bond) model and data of the electron structures. The misfit strain energies in Fe/TiC, Fe/ZrC and Fe/HfC systems were 0.390, 1.692 and 1.408 eV per 16 atoms(Fe: 8 atoms and MC; 8 atoms). More misfit energy was generated as difference of lattice parameters between the bulk Fe and the bulk MCs increased.

• Corrosion Science and Technology
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• v.20 no.5
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• pp.295-307
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• 2021

Effects of ε-carbide (Fe_2.4C) on corrosion and hydrogen diffusion behaviors of ultra-strong steel sheets for automotive application were investigated using a number of experimental and analytical methods. Results of this study showed that the type of iron carbide precipitated during tempering treatments conducted at below A₁ temperatures had a significant influence on corrosion kinetics. Compared to a steel sample with cementite (Fe₃C), a steel sample with ε-carbide (Fe_2.4C) showed higher corrosion resistance during a long-term exposure to a neutral aqueous solution. In addition, the diffusion kinetics of hydrogen atoms formed by electrochemical corrosion reactions in the steel matrix with ε-carbide were slower than the steel matrix with cementite because of a comparatively higher binding energy of hydrogen with ε-carbide. These results suggest that designing steels with fine ε-carbide distributed uniformly throughout the matrix can be an effective technical strategy to ensure high resistance to hydrogen embrittlement induced by aqueous corrosion.