• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.127-127
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• 2002

Methallothioneins(MTs) are low-molecular-mass cysteine-rich metal-binding proteins with high affinity for heavy metal ions, found in a large variety of organisms. Although the biological functions of MTS have not been fully elucidated, they are thought to play an important role in detoxification of toxic elements such as cadmium and mercury.(omitted)

• 공업화학
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• 제34권6호
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• pp.640-648
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• 2023

The purpose of this study was to determine the inhibitory effect of heavy metals [Cd(II), Ni(II), and Zn(II)] on the growth of Rhodobacter species (Rhodobacter blasticus, Rhodobacter sphaeroides, and Rhodobacter capsulatus) and their potential use for Cd(II), Ni(II), and Zn(II) bioremoval from liquid media. The presence of toxic heavy metals prolonged the lag phase in growth and reduced biomass growth for all three Rhodobacter species at concentrations of Cd, Ni, and Zn above 10 mg/L. However, all three Rhodobacter species also had a relatively high specific growth rate against each toxic heavy metal stress test for concentrations below 20 mg/L and possessed a potential bioaccumulation ability. The removal efficiency by all strains was highest for Cd(II), followed by Ni(II), and lowest for Zn(II), with the removal efficiency of Cd(II) by Rhodobacter species being 66% or more. Among the three strains, R. blasticus showed a higher removal efficiency of Cd(II) and Ni(II) than R. capsulatus and R. sphaeroides. Results also suggest that the bio-removal processes of toxic heavy metal ions by Rhodobacter species involve both bioaccumulation (intracellular uptake) and biosorption (surface binding).

• Membrane and Water Treatment
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• 제11권3호
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• pp.231-235
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• 2020

Industrialization and modern developments have led to an influx of toxic heavy metals into the aquatic environment, and the accumulation of heavy metals has serious adverse effects on humans. Among the various heavy metal treatment methods, adsorption is very useful and frequently used. Plastic materials, such as polypropylene and polyethylene, have been widely used as filter media due to their mechanical and chemical stability. However, the surface of plastic material is inert and therefore the adsorption capability of heavy metals is very limited. In this study, granular media and fiber media composed of polypropylene and polyethylene are used, and the surface modification was conducted in order to increase adsorption capability toward heavy metals. Oxygen plasma generated hydroxyl groups on the surface of the media to activate the surface, and then acrylic acid was synthesized on the surface. The grafted carboxyl group was confirmed by FT-IR and SEM. Heavy metal adsorption capability of pristine and surface modified adsorbents was also evaluated. Overall, heavy metal adsorption capability was increased by surface modification due to electrostatic interaction between the carboxyl groups and heavy metal ions. Fibrous PP/PE showed lower improvement compared to granular PP media because pore blockage occurred by the surface modification step, thereby inhibiting mass transfer.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_4호
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• pp.189-196
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• 2001

The blue green alga, Microcystis aeruginosa, was found to accumulate proline under the stressful concentration of cupric ions. The changes of proline level in Microcystis aeruginosa in response to copper(Cu) have been monitored and the function of the accumulated proline was studied with respect to its effect on Cu uptake. Exposure of Microcystis aeruginosa elevated concentrations of Cu led to accumulation of fee proline depending on the concentrations of the metal in the external medium. The greater the toxicity or accumulation of the metal, the higher the amount of proline in algal cells were found. When proline was exogenously supplied prior to Cu treatment, the absorption of Cu was markedly reduced. When exogenous proline was supplied after Cu treatment, it resulted in a remarkable desorption of the adsorbed Cu immediately after the addition of proline. Pretreatment of Microcystis aeruginosa with proline counteracted with metal-induced lipid peroxidation. The results of the present study showed a protective elect of proline on metal toxicity through inhibition of lipid peroxidation and suggested that the accumulation of proline may be related to the tolerance mechanism for dealing with Cu stress.

• 생명과학회지
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• 제19권5호
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• pp.553-560
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• 2009

$P_{1/2}$ 값을 참고로 비교한 알긴산, 폴리글루론산 및 폴리만뉴론산의 금속이온들에 대한 상대적인 친화성은 다음과 같다; 1) 알긴산: $Cu^{2+}$ > $Cd^{2+}$ > $Pb^{2+}$ > $Fe^{3+}$ >> $Zn^{2+}$ > $Sr^{2+}$ > $Ca^{2+}$ > $Co^{2+}$ >> $Cr^{6+}$ > $Mn^{2+}$ >> $Hg^{2+}$, $Mg^{2+}$, $Rb^+$, 2) 폴리글루론산: $Cd^{2+}$ > $Cu^{2+}$ > $Pb^{2+}$ > $Fe^{3+}$ >> $Ca^{2+}$ > $Sr^{2+}$, $Zn^{2+}$, $Co^{2+}$ >> $Mn^{2+}$ > $Cr^{6+}$ >> $Hg^{2+}$, $Mg^{2+}$, $Rb^+$, 그리고 3) 폴리만뉴론산: $Cd^{2+}$, $Cu^{2+}$ > $Fe^{3+}$ > $Pb^{2+}$ > $Ca^{2+}$ > $Zn^{2+}$ > $Sr^{2+}$ > $Co^{2+}$ > $Cr^{6+}$ >> $Mn^{2+}$ >> $Hg^{2+}$, $Mg^{2+}$, $Rb^+$. 알기산 1 g에 흡착하는 $Cd^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Pb^{2+}$, 및 $Zn^{2+}$의 양은 $363.5{\pm}45.0$, $226.3{\pm}9.2$, $1,299.4{\pm}$81.3, 500.7${\pm}$27.7 및 165.9${\pm}$11.4 mg이었으며, 폴리글루론산 1g에 흡착하는 $Cd^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Pb^{2+}$, 및 $Zn^{2+}$의 양은 354.5${\pm}$26.5, 177.6${\pm}$8.7, 1,288.6${\pm}$60.1, 424.0${\pm}$7.4 및 140.2${\pm}$28.5 mg이었으나, 폴리만뉴론산 1 g에 흡착하는 $Cd^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Pb^{2+}$, 및 $Zn^{2+}$의 양은 329.0${\pm}$10.3, 226.9${\pm}$1.9, 1,635.6${\pm}$11.1, 419.8${\pm}$12.6 및 251.0${\pm}$49.1 mg이었다. 폴리만뉴론산은 알긴산보다 높은 용해도와 폴리글루론산보다 높은 금속이온에 대한 친화성 때문에 독성이 높은 중금속이나 경제성이 높은 금속을 선택적으로 분리하는 데 사용할 수 있을 것이다.

• 한국세라믹학회지
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• 제43권2호
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• pp.136-141
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• 2006

The stabilizing behavior of heavy metals in the silicate glass containing Electric Arc Furnace dust (EAF dust) were studied by the Toxic Characterization Leaching Procedure (TCLP) test, and the change of crystalline phase and glass network structure were investigated as a function of EAF dust content added. The glass containing EAF dust of $30\;wt\%$ an oxygen/network former ratio(R) of $2\~3$ allowing a fairly stable network structure thus showed much lower heavy metal leaching concentration than that for containing EAF dust above $50\;wt\%$ at TCLP test. For the glass containing EAF dust $50\~60\;wt\%$, however, the R was over 3, which weakened the glass network structure and increased the heavy metals leachate. Adding the EAF dust to a glass decreased the degree of Si-O-Si symmetry and increased the number of non-bridging oxygen, which decreased the chemical durability of glasses. When the dust content in a glass was over $70\;wt\%$, the Zn and Fe ions reacted to form the spinel crystal rather than to bind to network structure of glass and leaching concentration of those ions from the specimen decreased, so the spinel phase could be attributed to lowering a heavy metal leaching.

• Current Applied Physics
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• 제18권11호
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• pp.1255-1260
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• 2018

In this work, a green and simple one-pot route was developed for the synthesis of highly fluorescent aminofunctionalized graphene quantum dots (a-GQDs) via hydrothermal process without any further modification or surface passivation. We synthesized the a-GQDs using glucose as the carbon source and ammonium as a functionalizing agent without the use of a strong acid, oxidant, or other toxic chemical reagent. The as-obtained aGQDs have a uniform size of 3-4 nm, high contents of amino groups, and show a bright green emission with high quantum yield of 32.8%. Furthermore, the a-GQDs show effective fluorescence quenching for $Cu^{2+}$ ions which can serve as effective fluorescent probe for the detection of $Cu^{2+}$. The fluorescent probe using the obtained aGQDs exhibits high sensitivity and selectivity toward $Cu^{2+}$ with the limit of detection as low as 5.6 nM. The mechanism of the $Cu^{2+}$ induced fluorescence quenching of a-GQDs can be attributed to the electron transfer by the formation of metal complex between $Cu^{2+}$ and the amino groups on the surface of a-GQDs. These results suggest great potential for the simple and green synthesis of functionalized GQDs and a practical sensing platform for $Cu^{2+}$ detection in environmental and biological applications.

• 자원환경지질
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• 제32권6호
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• pp.611-631
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• 1999

Enviromental geochemisty and heary metal contamination at the Kongjueil mine creek were underaken on the basis of physicohemical properties and mineralogy for various kinds of water (surface, mine and ground water),soil, precipitate and sediment collected of April and December in 1998. Hydrgeochemical composition of the water samples are characterized by relatively significant enricant of Ca+Na, alkiali ions $NO_3$ and Cl inground and surfore water, wheras the mine waters are relatively eneripheral water of the mining creek have the characteristics of the (Ca+Mg)-$(HCO_3+SO_4)$type. The pH of the mine water is high acidity (3.24)and high EC (613$\mu$S/cm)compared with those of surface and ground water. The range of $\delta$D and $\delta^{18}O$ values (relative to SMOW) in the waters are shpwn in -50.2 to -61.6% and -7.0 to -8.6$\textperthousand$(d value=5.8 to 8.7). Using computer program, saturation index of albite, calcite, dolomite in mine water are nearly saturated. The gibbiste, kaolinite and smectite are superaturated in the surface and ground water, respectively. Calculated water-mineral reaction and stabilities suggest that weathing of silicate minerals may be stable kaolinite owing to the continuous water-rock reaction. Geochemical modeling showed that mostly toxic heavy metals may exist larfely in the from of metal-sulfate $(MSO_4\;^2)$and free metal $(M^{2+})$ in nmine water. These metals in the ground and surface water could be formed of $CO_3$ and OH complex ions. The average enrichment indices of water samples are 2.72 of the groundwater, 2.26 of the surface water and 14.15 of the acid mine water, normalizing by surface water composition at the non-mining creek, repectively. Characteristics of some major, minor and rate earth elements (Al/Na, K/Na, V/Ni, Cr/V, Ni/Co, La/Ce, Th/Yb, $La_N/Yb_N$, Co/Th, La/Sc and Sc/Th) in soil and sediment are revealed a narrow range and homogeneous compositions may be explained by acidic to intermediate igneous rocks. And these suggested that sediment source of host granitic gneiss colud be due to rocks of high grade metamorphism originated by sedimentary rocks. Maximum concentrations of environmentally toxic elements in sediment and soil are Fe=53.80 wt.% As=660, Cd=4, Cr=175, Cu=158, Mn=1010, Pb=2933, Sb=4 and Zn=3740 ppm, and extremely high concentrations are found are found in the subsurface soil near the ore dump and precipitates. Normalizing by composition of host granitic gneiss, the average enerichment indices are 3.72 of the sediments, 3.48 of the soils, 10.40 of the precipitates of acid mine drainage and 6.25 of the soils near the main adit. The level of enerichment was very severe in mining drainage sediments, while it was not so great in the soils. mineral composition of soil and sediment near the mining area were partly variable being composed of quartz, mica, feldspar, chlorite, vermiculite, bethierin and clay minerals. reddish variable being composed of quartz, mica, feldspar, chlorite, vermiculite, bethierin and clay minerals. Reddish brown precipitation mineral in the acid mine drainage identifies by schwertmanite. From the separated mineralgy, soil and sediment are composed of some pyrite, arsenopyite, chalcopyrite, sphalerite, galena, malachite, goethite and various kinds of hydroxied minerals.

• 미생물학회지
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• 제50권1호
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• pp.22-26
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• 2014

Protocatechualdehyde (PA)는 항산화 활성과 항암 활성을 가진 페놀성 물질이다. Streptomyces lincolnensis M-20 균주에서 생산된 PA를 균주 상등액에서 분리, 정제하였다. 항산화 활성을 가진 PA가 구리 이온 존재 하에서는 산화촉진제로 작용하였다. 항산화 활성은 DPPH를 이용한 방법으로 측정하였으며, 구리 이온 존재 하에서 PA의 산화 촉진 작용은 pBR322 플라스미드의 DNA 절단 작용으로 측정하였다. DNA 손상으로 생성되는 활성산소 종의 확인은 활성 산소종의 포집자인 글루타치온에 의해 DNA 절단이 억제되는 것으로 확인하였다. PA와 구리 이온의 복합체 형성은 금속 이온의 킬레이트인 EDTA가 존재할 경우와 존재하지 않을 경우를 자외선/가시광선 분광학적 분석법으로 비교, 확인하였다.

• 대한환경공학회지
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• 제27권11호
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• pp.1146-1152
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• 2005

개시제로 potassium persulfate($K_2S_2O_8$)를 사용하여 methylcellulose(MC)에 중금속 이온과 친화력이 우수한 carboxyl(-COOH)기를 도입하기 위하여 acrylic acid(AA)를 그라프트 공중합시켜 얻어낸 반응생성물(MC-g-AA)을 중금속 이온 흡착제로 적용하였다. MC-g-AA의 그라프트율은 개시제 및 단량체의 농도가 높을수록 증가하였으며 그라프트율 19.7% 이상의 MC-g-AA는 물에 용해되지 않았다. MC-g-AA의 중금속 흡착 특성을 평가하기 위해 MC-g-AA의 기라프트율, 폐수의 pH, 흡착시간, MC-g-AA의 주입량 및 폐수내 $Pb^{2+}$, $Cu^{2+}$ 이온의 농도에 따른 흡착실험을 진행하였다. 흡착실험 결과 MC-g-AA는 pH $4{\sim}6$ 범위에서 $Pb^{2+}$, $Cu^{2+}$ 이온에 대한 높은 흡착량을 나타내었으며 그라프트율 및 초기 중금속 이온의 농도가 높을수록 MC-g-AA의 중금속 흡착량은 증가하였으나 MC-g-AA의 주입량이 늘어날수록 MC-g-AA 단위 무게당 흡착량은 감소하였다. MC-g-AA에 의한 중금속 흡착을 Freundlich 등온흡착 모델로 표현한 $Pb^{2+}$, $Cu^{2+}$ 이온의 l/n은 각각 0.4294, 0.3453로 나타났다.