• The Korean Journal of Ecology
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• v.21 no.3
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• pp.225-231
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• 1998

The studies on the potentiality of biomonitoring heavy metal pollution in coastal region of industrial complex were performed to investigate the heavy metal accumulation and induction of metal-binding protein (MBP) as detoxification process using Rumex maritimus. Bioconcentration in organs and MBP in root of R. maritimus was investigated for the research of the tolerance of heavy metals. The bioconcentration of cadmium and zinc in organs showed 3.6-8.0 times in root higher than in shoot, so it was found that heavy metal accumulated selectively in root. MBP increased absorbance in 254 nm and decreased in 280 nm, because it was composed of high cystein content and low aromatic acids, so absorbance had large difference between 254 nm and 280 nm. The existence of MBP in the 10-20 fraction was ascertained with anion exchange chromatography and it was identified that concentration of heavy metal increased according as an exposure concentration of medium increased in QAE Sephadex A-25 elution profile. These results suggested that MBP could play a role in biomarker determining the bioconcentration of plant. This study demonstrated a possibility that removal ability of heavy metal of R. maritimus resulted from detoxification process and MBP could be utilized as a biomarker of heavy metal pollution.

• The Korean Journal of Ecology
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• v.19 no.6
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• pp.519-527
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• 1996

To examine the possibility of biomonitoring of heavy metal removal ability and soil, a study was performed to investigate the heavy metal removal ability and metal-binding protein (MBP) as detoxification process using Oenanthe stolonifera. After O. stolonifera was exposed to individuals (cadmium, zinc) and mixture (cadmium+zinc)for 4 days, removal rate of heavy metal and pH in the treatment medium was measured. MBP was assayed by means of ion exchange column chromatography. The exposure to mixture (Cd:76.8%, Zn:75%) rather than individuals (Cd:82.9%, Zn:90.4%) showed a synergism raising the toxic effect. Initial removal rate was different for each heavy metal : in case of exposure to cadmium it was over 60% on day 1, while for zinc it was 75~90% on day 4. Throughout the experimental period, pH value of treatment medium continuously decreased, since cortex in the roots may secret organic acid to adjust and prevent toxicity of metals. The existence or MBP in the 70~80 fraction and the presence of Zn-enzyme pool was ascertained with the column chromatography. This study demonstrated a possibility that heavy utilized as a biomarker of heavy metal pollution.

• Journal of Ginseng Research
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• v.16 no.1
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• pp.24-30
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• 1992

Extracts of Panax ginseng root significantly induced tolerance of Fusarium oxysporum to heavy metal, mecury, as the fungal mycelial growth was less inhibited by mercury chloride on potato dextrose medium(PDA) amended with ginseng root than on the PDA with no ginseng amendment. The most favorable concentration of ginseng root powder in detoxification of mercury chloride was 1%. The induced tolerance of F. oxysporum to mercury chloride appeared to be rather due to absorption of ginseng components, and was not related to stimulation of mycelial growth of the fungus per so by ginseng treatment. Ginseng components responsible for inducing tolerance of the fungus to mercury were involved in the water fraction of the ginseng root extract, although the water fraction had no effect on enhancement of the mycelial growth on the medium without mercury chloride. The hexane fraction of ginseng root extract, by which the mycelial growth was stimulated, was not related to the inducement of the tolerance to mercury chloride. However, more tolerance to mercury chloride was noted in PDA with both the water and hexane fractions combined than with either of the two fractions. Six-year-old ginseng roots were more effective in detoxification of mercury chloride than 4-year-old ginsng roots, and American ginseng (P quinquifolium) had no or little effect on inducing tolerance of the fungus to mercury chloride. This method may be used to screen other natural materials for test in the detoxification of mercury chloride.

• Ocean Science Journal
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• v.41 no.1
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• pp.43-51
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• 2006

Concentration and distribution of Fe, Zn, Cu, Cd, Mn, Pb, Ni among subcellular fractions (cellular membrane structures and cytosol) and Zn, Cu, Cd among cytoplasmic proteins in the kidney and digestive gland of mussel Modiolus modiolus living along a polymetallic concentration gradient were studied. It was found in the kidney of M. modiolus from contaminated sites that the Fe percent increased in the "membrane" fraction, whereas Zn, Pb, Ni and Mn percent increased in the cytosol compared to the kidney of the control mussel. Note kidney cytosol of M. modiolus from clean and contaminated sites sequestered major parts of Cu and Cd. In the digestive gland of M. modiolus from contaminated sites Fe, Zn, Cd, Mn, Ni percent increased in the "membrane" fraction, whereas Cu, Pb percent increased in the cytosol compared to digestive gland of control mussel. Gel-filtration chromatography shows kidney of M. modiolus contains increased metallothionein-like protein levels irrespective of ambient dissolved metal concentrations. It was shown that the metal detoxification system in the kidney and digestive gland of M. modiolus was efficient under extremely high ambient metal levels. However, under complex environmental contamination in the kidney of M. modiolus, the metal detoxification capacity of metallothionein-like proteins was damaged.

• Journal of Convergence for Information Technology
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• v.10 no.12
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• pp.208-215
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• 2020

The purpose of this study was to access the effects of detoxification of hair by SUKI(silver tools). The subjects of this study participated 26 persons(EG 13 and CG 13), Experimental group was performed SUKI programs combined with scalp and hair for two times per week, during 8 weeks. The results was of comparison of variations in each groups showed that there was a significant difference(6items) in the experimental group(p<.05). But 2items(Pb, Cs) was not showed it. Among the hazardous heavy metals in research, Al, Ba and Hg showed the greatest reduction rate of difference. Thus, the using of the SUKI tool has been shown to affect some heavy metal emissions (p<.05). In conclusion, it is thought that it can be used as basic data for heavy metal discharge of scalp through continuous research in the future.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1522-1542
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• 2019

To adapt to environmental changes and to maintain cellular homeostasis, microorganisms adjust the intracellular concentrations of biochemical compounds, including metal ions; these are essential for the catalytic function of many enzymes in cells, but excessive amounts of essential metals and heavy metals cause cellular damage. Metal-responsive transcriptional regulators play pivotal roles in metal uptake, pumping out, sequestration, and oxidation or reduction to a less toxic status via regulating the expression of the detoxification-related genes. The sensory and regulatory functions of the metalloregulators have made them as attractive biological parts for synthetic biology, and the exceptional sensitivity and selectivity of metalloregulators toward metal ions have been used in heavy metal biosensors to cope with prevalent heavy metal contamination. Due to their importance, substantial efforts have been made to characterize heavy metal-responsive transcriptional regulators and to develop heavy metal-sensing biosensors. In this review, we summarize the biochemical data for the two major metalloregulator families, SmtB/ArsR and MerR, to describe their metal-binding sites, specific chelating chemistry, and conformational changes. Based on our understanding of the regulatory mechanisms, previously developed metal biosensors are examined to point out their limitations, such as high background noise and a lack of well-characterized biological parts. We discuss several strategies to improve the functionality of the metal biosensors, such as reducing the background noise and amplifying the output signal. From the perspective of making heavy metal biosensors, we suggest that the characterization of novel metalloregulators and the fabrication of exquisitely designed genetic circuits will be required.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.295.1-295.1
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• 2002

Metallothioneins (MTs) are a go up of heavy metal-binding proteins characterized by cystein-rich low molecular weight(6000 - 10.000 Da). They plays a major role in the detoxification of heavy metals and also in scavenging of superoxide radicals. They are known to be induced by heavy metals in various organs of different species and represent a potential biomarker of aquatic heavy metal contamination. (omitted)

• Journal of Life Science
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• v.19 no.12
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• pp.1685-1689
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• 2009

Phytochelatins (PCs) are small polypeptides synthesized by PC synthase (PCS). They are present in various living organisms including plants, fission yeast, and some animals. The presumed function of PCs is the sequestration of cytosolic toxic heavy metals like cadmium (Cd) into the vacuoles via vacuolar membrane localized heavy metal tolerance factor 1 (HMT-1). HMT-1 was first identified in fission yeast (SpHMT-1), and later in Caenorhabdtis (CeHMT-1). Recently, its homolog has also been found in PC-deficient Drosophila (DmHMT-1), and this homolog has been shown to be involved in Cd detoxification, as confirmed by the heterologous expression of DmHMT-1 in fission yeast. Therefore, the dependence of HMT-1 on PC in Cd detoxification should be re-evaluated. I heterologously expressed SpHMT-1 in cytosolic PC-deficient yeast, Saccharomycea cerevisiae, to understand the dependence of HMT-1 on PC. Yeast cells expressing SpHMT-1 showed increased tolerance to Cd compared with control cells. This result indicates that SpHMT-1 is not strictly correlated with PC production on its function. Moreover, yeast cells expressing SpHMT-1 showed increased tolerance to exogenously applied glutathione (GSH) compared with control cells, and the tolerance to Cd was further increased by exogenously applied GSH, while tolerance in control cells was not. These results indicate that the function of SpHMT-1 in Cd detoxification does not depend on PCs only, and suggest that SpHMT-1 may sequester cytosolic GSH-Cd complexes into the vacuole.

• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.895-908
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• 2023

Disposal of waste containing heavy metals into the environment is a major threat to human health and can result in toxic or chronic poisoning in aquatic life. In the current study, metal-resistant Raoultella ornithinolytica was isolated from metal-contaminated samples collected from the Tanjaro River, located southwest of Sulaymaniyah, Iraq. R. ornithinolytica was identified by partial amplification of 16S rRNA. The uptake potency of heavy metals was assessed using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and indicated that R. ornithinolytica removed 67, 89, 63.4, 55.6, 56.5, 65, and 61.9% of Cd, Pb, Cr, Ni, Zn, Co, and Fe, respectively. These removal rates were influenced by temperature, pH, and contact time; at 35℃ and pH 5 with a change in the incubation time, the reduction rate improved from 89 to 95% for Pb, from 36.4 to 45% for Cu, and from 55.6 to 64% for Ni. Gene analysis indicated that R. ornithinolytica contained pbrT, chrB, nccA, iroN, and czcA genes, but the pcoD gene was absent. Energy-dispersive X-ray spectroscopy (EDS) images showed evidence of metal ion binding on the cell wall surface with different rates of binding. Transmission electron microscopy (TEM) detected different mechanisms for metal particle localization; cell surface adsorption was the main mechanism for Pb, Zn, and Co uptake, while Cd, Ni, and Fe were accumulated inside the cell. The current study describes, for the first time, the isolation of R. ornithinolytica from metal-contaminated water, which can be used as an eco-friendly biological expedient for the remediation and detoxification of metals from contaminated environments.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.1
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• pp.75-80
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• 2016

This study was conducted to evaluate effect of chemical amendments on reducing bioavailable fraction of heavy metals in soil along with ecotoxicological effect on earthworms, Eisenia fetida. Three different chemical amendments, lime (L), steel slag (SS), and acid mine drainage sludge (AMDS), were applied with varied application ratio (1, 3, 5%). Heavy metal contaminated soil was mixed with chemical amedments and earthworms, Eisenia fetida, were cultivated for 28 days. Bioavailable fraction of heavy metals (Cd, Cu, Pb, and Zn) extracted with 0.1N HCl was monitored and also, mortality, growth, and metal concentration in earthworm were assessed. Result showed that all three amendments had high efficiency to reduce bioavailable fraction of heavy metals in soil. In particular, lime showed the highest reduction rate of Cu (63.9-87.7%), Pb (7.90-24.65%), and Zn (40.83-77.60%) among three amendments. No mortality of earthworm was observed during experimental period except 3% and 5% AMDS treatment indicating that application of chemical amendments is safe in terms of ecotoxicological aspect. However, no positive correlation was observed between reduction of bioavaialble fraction of heavy metals in soil and earthworms. Overall, application of chemical amendments in agricultural field can be adapted for reducing bioavailable fraction of heavy metals and detoxification in soil.