• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2002년도 춘계학술발표대회 및 심포지움
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• pp.138-138
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• 2002

Oxidative stress has been associated with a number of diseases in human. Among the sources that can generate oxidative stress, it has been reported that iron can generate reactive oxygen species (ROS)with thiol. In iron overload state, increased thiol levels in plasma appeared to be associated with human mortality. In this study we examined whether iron could interact with thiols in plasma, generating ROS. In human plasma, unlike with Fe(III), Fe(II) increased lucigenin-enhanced chemiluminescence in concentration-dependent manner, and this was inhibited by SOD. Boiling of plasma did not affect chemiluminescence induced by Fe(II). Hovever, thiol depletion in plasma by pretreatment with N-ethylmaleimide (NEM)decreased Fe(II)-induced chemiluminescence significantly, suggesting that Fe(II) generated superoxide anion by the nonenzymatic reaction with plasma thiol. Consistent with this findings, albumin, the major thiol contributor in plasma, also generated ROS with Fe(II) and this generation was inhibited by pretreatment with NEM. Treatment with Fe(II) to plasma resulted un significant reduction of oxygen radical absorbance capacity (ORAC) value, suggest that total antioxidant capacity could diminished in iron overload state. In conclusion, In iron overload state, plasma may be affected by oxidative stress mediated by nonenzymatic reaction of Fe (II)with plasma thiol.

• 한국표면공학회지
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• 제28권1호
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• pp.14-22
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• 1995

The effects of iron content in coated layer, surface roughness and lubricants on the formability of commercial Zn-Fe alloy electroplated steel sheets used for automotive bodies were investigated. The higher the iron content in deposit, the lower the friction coefficient of Zn-Fe alloy electroplated steel sheets. The surface roughness of coated layer hardly influenced the frictional characteristics. The formability of Zn-Fe alloy electroplated steel sheets was found to be more affected by the lubricant than by iron content in Zn-Fe alloy electrodeposit.

• 대한약리학회지
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• 제27권1호
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• pp.69-80
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• 1991

Iron(II)에 의한 마이크로좀의 지질 과산화에 미치는 quercetin과 rutin의 억제 효과를 iron의 산화중에서 생성되는 산소 라디칼에 대한 제거 작용과 iron에 대한 킬레이트 작용에 관하여 관찰하였다. $Fe^{2+}$ 단독에 의한 지질 과산화는 quercetin 또는 rutin에 의하여 용량에 따라 현저하게 억제되었다. $Fe^{2+}$의 존재하에서 ascorbate또는 NADPH에 의한 지질 과산화는 quercetin과 rutin에 의하여 거의 완전히 억제되었다. $Fe^{2+}$의 과산화 작용은 SOD와 DABCO에 의하여 억제되었고 catalase, DMSO와 mannitol에 의하여 약간 억제되었다. Quercetin과 rutin은 DETAPAC에 반응하는 $Fe^{2+}$의 산화를 억제하였고 반응초기에 유의한 킬레이트 효과를 나타내었다. Quercetin과 rutin은 효과적으로 $H_{2}O_{2}$에 의한 지질 과산화를 억제하였으며 $H_{2}O_{2}$를 분해하였다. $Fe^{2+}$의 존재하에서 $OH{\cdot}$의 생성과 U.V. 조사에 의한 $^1O_2$의 생성은 모두 quercetin과 rutin에 의하여 억제되었다. $Cd^{2+},\;Cu^{2+},\;Ni^{2+},\;Pb^{2+}$와 $Zn^{2+}$에 의한 지질 과산화는 quercetin에 의하여 거의 완전하게 억제 되었다. Quercetin과 rutin은 $Fe^{2+}$에 의한 sulfhydryl기의 손실을 유의하게 저해 하였다. 이상의 결과로부터 ascorbate와 NADPH가 있거나 없는 상태에서 $Fe^{2+}$의 과산화 작용에 대한 quercetin과 rutin의 억제 효과는 그들의 반응성 산소 대사물에 대한 제거 작용과 iron에 대한 킬레이트 작용에 기인하였을 것으로 시사된다.

• Journal of Nutrition and Health
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• 제26권7호
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• pp.887-898
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• 1993

In order to determine the effect of iron depletion and subsequent supplementation on the muscle capacity for peroxisomal (PO) and mitochondrial(MO) $\beta$-oxidation during high fat feeding, weanling rats were fed a 44% (HF) or 2.5% (LF) fat diet with (+Fe) or without (-Fe) iron for 6 or 9 weeks. After 1 week rats fed HF+Fe or HF-Fe had 50-100% more PO and MO in heart, soleus, psoas and gastrocnemius than did rats fed low fat, but after 3 weeks rats fed HF-Fe had lower muscle PO and MO. In muscles of iron depleted rats PO and MO were not increased by supplementation with iron for 3 weeks. After 6 weeks MO and PO in skeletal muscles of rats fed HF+Fe were lower than after 3 weeks. It is concluded that adequate iron is necessary for miaximum response of muscle PO and MO to high fat feeding. However, after 6 weeks both PO and MO have returned to levels similar to those of rats fed low fat diets, hence, the elevated catalase activities seen at this time do not reflect peroxisomal $\beta$-oxidation.

• 대한화학회지
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• 제24권3호
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• pp.233-238
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• 1980

팔면체형 철(Ⅱ)착물 $[Fe(DPGH)_2(NH_3)_2$]과 산소분자의 반응에서 생성된 산소화생성물, $[(DPGH)_2FeO_2Fe(DPGH)_2$]의 자기모멘트를 측정하였다. 산소화 생성물내의 철에 대한 자기모멘트는 $298^{\circ}K$에서 3.60 B.M (Bohr Magneton)이며 온도가 내려 감에따라 감소되어 $4.2^{\circ}K$에선 1.65 B.M의 값을 보여준다. 이상의 측정결과는 다음과 같이 설명될 수 있다. (1) 산소화생성물내의 두개의 철(Ⅲ)은 중간스핀상태(S=3/2)를 갖는다. (2) 분자내의 두개의 철(Ⅲ)은 서로 약한 반강자성 짝지음을 일으킨다. 짝지음 상수는 정도이다.

• Journal of Nutrition and Health
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• 제37권8호
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• pp.645-654
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• 2004

This study examined the effect of excess calcium (Ca) on the iron (Fe) bioavailability and bone growth of marginally Fe deficient animals. Two groups of weanling female SD rats were fed either normal Fe (35 ppm) or Fe deficient diet (8 ppm) for 3 weeks. Then each group of animals were assigned randomly to one of three groups and were fed one of six experimental diets additionally for 4 weeks, containing normal (35 ppm) or low (15 ppm) Fe and one of three levels of Ca as normal (0.5%), high (1.0%), or excess (1.5%). Feces and urine were collected during the last 3 days of treatment. After sacrifice blood, organs, and femur bone were collected for analysis. Final body weight and average food intake were not affected by either the levels of dietary Ca or Fe. Low Fe diet significantly reduced the level of serum ferritin, however, for Hb, Hct, and TIBC no difference was shown than those in the normal Fe group. TIBC increased slightly by high and excess Ca intake in low Fe groups. For both normal and low Fe groups, high and excess Ca intakes reduced the apparent absorption of Fe and Fe contents of liver significantly (p < 0.05). Calcium contents in kidney and Femur of rats that were fed high and excess levels of Ca were significantly greater than those of normal Ca groups. However, weight, length, and breaking force of the bone were not affected by increased Ca intakes. Both in control and low Fe groups, high and excess intakes of Ca decreased the apparent absorption of Ca. These results indicate that the excess intakes of calcium than the normal needs would be undesirable for Fe bioavailability and that the adverse effects be more serious in marginally iron deficient growing animals. In addition bone growth and strength would not be favorably affected by high Ca intakes, though, the long term effect of increased Ca contents in bone requires further examination.

• 자원환경지질
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• 제53권3호
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• pp.297-306
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• 2020

보오크사이트로부터 알루미나를 생산하는 Bayer 공정 부산물인 레드머드는 높은 pH와 나트륨(Na)의 함량으로 폐기물로 분류되어, 발생량을 줄이거나 재활용하는 공정의 개발은 환경적으로 중요한 이슈이다. 본 연구에서는 레드머드 내 다량 함유된 철(Fe)을 자원가치를 갖는 품위(56wt.%) 이상으로 향상시키고자 레드머드에 활성탄과 황을 혼합하여 마이크로웨이브 가열 시험을 수행하였다. 가열 소성과정에서 레드머드 혼합물 분말시료는 유리화된 다공성 구조의 결합체로 변화되었으며, X-선 회절분석을 통하여 산출물은 침철석, 영가철(Fe⁰, iron), 자류철석(Fe_1-xS) 및 황철석(FeS₂) 등으로 구성됨을 확인하였다. 가열 소성 결과물은 왕수분해를 통하여 Fe을 용해시키고, NaCl을 첨가하여 Fe을 침전 회수하였다. 레드머드 내 Fe의 회수는 시험 조건별로 상이하게 나타났으며, 단순히 레드머드를 마이크로웨이브 가열한 시료 내 Fe은 그 함량이 49.0wt.% 였다. 그러나, 활성탄을 첨가한 시료 및 활성탄과 황을 첨가한 레드머드 시료의 가열 소성 결과물 내 Fe의 함량은 각각 58.0wt.%, 59.5wt.% 로서 철 자원가치 품위인 56wt.%를 초과하였다.

• 한국표면공학회지
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• 제20권4호
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• pp.144-153
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• 1987

In the case of dipping the Ni-Resist cast iron into molten aluminum with iron content, the thickness of intermetallic compound was remarkably increased with increasing iron content. The thickness was shown by following equation in the range of 1-3% iron content; $x=22.5t^{1/2}+4.47{\cdot}t{\cdot}(Fe%)$. where, x is thickness(${\mu}m$), t the time (minute), Fe% the iron w/o. When the Ni-Resist cast iron was dipped into the molten aluminum containing zinc content, the intermetallic compound thickness was also increased with increasing zinc contents. And thickness was represented by the following equation in the range of 2-10% zinc content; $x=3.46t^{1/2}+0.27{\cdot}t{\cdot}(Zn%)$. However, in the case of dipping the Ni-resist cast iron into molten aluminum with silicon content, the thickness of intermetallic compound was decreased with increasing silicon content, as shown in the following equation; $x=7.17t^{1/2}-0.15{\cdot}t{\cdot}(Si%)$. The intermetallic compound formed onto Ni-Resist cast iron was identified to be $FeAl_3\;and\;Fe_3Al$. As the result of hardness measurement, the peak hardness appeared in the intermetallic compound at near interface of the cast iron and the compound.

• Korean Chemical Engineering Research
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• 제46권3호
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• pp.512-515
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• 2008

본 연구는 염화네오디뮴 수용액으로부터 Fe 성분 제거를 위하여 Alamine 336을 이용한 Fe의 용매추출을 수행함에 있어서, Alamine 336의 농도, 염산 및 염소이온 농도에 따른 Fe 추출 특성 및 유기상으로 추출된 Fe의 탈거공정에 있어 상비와 탈거 용액의 염산 농도의 영향들을 고찰하였다. Alamine 336을 사용하여 Nd, Fe 혼합 용액으로부터 Fe 만을 선택적으로 추출할 수 있다는 것을 확인하였으며, 수상의 염산 및 염소이온 농도 증가에 의해 Fe의 추출율이 증가하였다. Fe가 추출된 Alamine 336을 증류수로 탈거할 경우 A/O비 4인 조건에서 99%의 Fe를 탈거할 수 있었으며, 탈거 용액의 염산 농도가 증가할수록 Fe 탈거율이 감소하였다.

• 동아시아식생활학회지
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• 제4권2호
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• pp.9-16
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• 1994

This study was undertaken to investigate the effects of dietary low (Fe) levels on Fe metabolism of cadmium(Cd) poisoned rats. 40 male Sprague weaning Dawley rats weighing 80-90g were divided into 4 groups(LFe:low Fe, LFeCd:low Fe and Cd, AFe: adequate Fe, AFeCd: adequate Fe and Cd) according to Cd administration(0, 50ppm in drinking water) and Fe levels(Fe:6ppm, 40ppm in diet)for 12 weeks. The food intake and body weight gain of Cd group with low Fe(LFeCd) were significantly lower than those of without Cd group with adequate Fe(AFe)(p<0.01, P<0.05). But there was no significantly difference between Cd groups and without Cd groups in water intake. The blood levels of hemoglobin, hematocrit, and serum levels of Fe of LFeCd were significantly lower than those of AFe(p<0.01, p<0.05, p<0.001). The urinary and fecal excretion of Fe of LFeCd was significantly lower than that of AFe(p<0.05, p0.05). The levels of Fe of liver, spleen in LFeCd were lower than those of AFeCd(p<0.05, p<0.05). These results indicates that adequate iron supplementation to Cd pretreated rats induce protective effects on the reduction of Fe status by Cd poisoning.