• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.176-186
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• 2022

Continued fenvalerate use has caused serious environmental pollution and requires large-scale remediation. Dibutyl phthalate (DBP) was discovered in fenvalerate metabolites degraded by Citrobacter freundii CD-9. Coculturing is an effective method for bioremediation, but few studies have analyzed the degradation pathways and potential mechanisms of cocultures. Here, a DBP-degrading strain (BDBP 071) was isolated from soil contaminated with pyrethroid pesticides (PPs) and identified as Stenotrophomonas acidaminiphila. The optimum conditions for DBP degradation were determined by response surface methodology (RSM) analysis to be 30.9 mg/l DBP concentration, pH 7.5, at a culture temperature of 37.2℃. Under the optimized conditions, approximately 88% of DBP was degraded within 48 h and five metabolites were detected. Coculturing C. freundii CD-9 and S. acidaminiphila BDBP 071 promoted fenvalerate degradation. When CD-9 was cultured for 16 h before adding BDBP 071, the strain inoculation ratio was 5:5 (v/v), fenvalerate concentration was 75.0 mg/l, fenvalerate was degraded to 84.37 ± 1.25%, and DBP level was reduced by 5.21 mg/l. In addition, 12 fenvalerate metabolites were identified and a pathway for fenvalerate degradation by the cocultured strains was proposed. These results provide theoretical data for further exploration of the mechanisms used by this coculture system to degrade fenvalerate and DBP, and also offer a promising method for effective bioremediation of PPs and their related metabolites in polluted environments.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.696-700
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• 1999

The effects and behaviors of heavy metals incoming from industrial by-products were investigated in cement clinker reaction. The raw meal containing 500 ppm of heavy metal ion such as Cu, Cd, Cr, and Pb was calcined at $1450^{\circ}C$ for 30 minutes. Burnability index, fixation concentration of heavy metals in clinker, and apportionment ratio were analyzed. Pb had a minimum fixation concentration of under 5% and Cr had a maximum over 85%. The burnability of Cr containing clinker was lower than that of others as the result of higher value of 3.41% of free lime after calcination at $1450^{\circ}C$. Cu, Cd, and Pb had not any significant effects on the clinker reactitivity. The volatility of heavy metals produced lots of macropores and micropores in clinker and minerals. Cd and Cr were the major apportionments in alite and belite and Cu in interstitial phase. Pb was existed under the detection limit of EDAX analysis due to its higher volatility.

• Korean Journal of Ecology and Environment
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• v.53 no.1
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• pp.91-101
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• 2020

Stormwater runoff is known as a major non-point water pollution source that transports heavy metals, which have accumulated in road surface, to stream and coastal area. Dissolved and particulate metals in stormwater runoffs have been investigated to understand the outflow characteristics of heavy metals during rainfall events and to identify their pollution sources. The concentration of dissolved Co and Ni decreased after the outflow with high concentrations at the beginning of the rainfall, and other metals showed different characteristics depending on the rainfall and rate of discharge. Particulate metals showed a similar trend with the temporal variation of suspended solids concentration in stormwater runoffs. The results of geo-accumulation index (I_geo) indicated that the stormwater runoffs from industrial region were very highly polluted with Cu, Zn and Cd. As a result of comparing the metal concentrations of <125 ㎛ for road dust near the study area, Cu, Zn and Cd were originated from inside of metal manufacturing facilities rather than traffic activities at road surface and these metals accumulated on the surface area of facilities were transported to the water environments during stormwater event. The average discharged amounts of heavy metals for one rainfall event were Cr 128 g, Co 12.35 g, Ni 98.5 g, Cu 607.5 g, Zn 8,429.5 g, As 6.95 g, Cd 3.7 g, Pb 251.75 g, indicating that metal runoff loads in the stormwater runoffs are closely related to surrounding industry types.

• Applied Chemistry for Engineering
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• v.30 no.4
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• pp.429-434
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• 2019

A lateral flow immunoassay platform utilizing antibody functionalized water soluble CdSe/ZnS semiconductor quantum dots (QDs) was developed for the analysis of human serum amyloid A-1 (hSAA1) in a buffer solution. hSAA1 was chosen as a target protein because it is regarded as a potential biomarker associated with early diagnosis and prognosis in patients of lung cancer. The immunoassay strip on a nitrocellulose membrane was fabricated by spraying two lines composed of a test line with a monoclonal antibody against hSAA1 (10G1) (anti hSAA1) and a control line of anti-chicken IgY. While the CdSe/ZnS QDs synthesized in an organic phase were transferred to a water phase by ligand exchange using carboxylic acid modified alkane thiol. The QDs was then conjugated to monoclonal antibody against hSAA1 (14F8) [anti hSAA1 (14F8)] and used as a fluorescent detection probe. The sequential lateral flow of hSAA1 in different concentration and QDs-anti hSAA1 (14F8) complex allowed to form the surface sandwich complex of anti hSAA1 (10G1)/hSAA1/QD-anti hSAA1 (14F8), which was then analyzed using fluorescence microscope. A 100 nM concentration of hSAA1 protein can be detected by naked eyes under an optimized lateral flow buffer condition with a sensing time of 5 mins.

• Applied Microscopy
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• v.47 no.3
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• pp.148-156
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• 2017

The wide distribution of redox-sensitive elements (RSE) as arsenic (As), cadmium (Cd), selenium (Se), and strontium (Sr) in the top soil of Siwaqa area are related to the weathering action of alkaline surface and groundwater on the parent rocks. The bioavailability, distribution, sorption, and ecotoxicity of As, Cd, Se, and Sr, of the wild plants and top soils in the study area were investigated. A total number of 23 surface soil samples and 23 plant samples were collected and analyzed for the most toxic elements. The uptake of elements by plants was dependent on the plant species and the concentration of elements in the soil. For example, Sr was the highest concentration in soil samples and plants, while Se was the lowest concentration in soil samples and pants. For the plants, the results showed that Bellevalia sp. had the highest elements uptake, while Allium rothii had the lowest elements uptake. The results of this work provide a valuable knowledge for understanding the bioavailability of some toxic elements in the soil and plants of Central Jordan. The results are expected to be of great help for the Jordanian Uranium Mining Company during their environmental risk assessments.

• KSBB Journal
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• v.11 no.2
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• pp.173-180
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• 1996

The contamination of the environment by heavy metals results in a serious public health problem due to the toxicity of those pollutants even at low concentrations. Microorganisms may be used to remediate wastewaters contamlialtd with heavy metals. The waste S. cerevisiae is an inexpensive readily available source of biomass for bioremediation of wastewater. S. cerevisiae was investigated for their ability to absorb Pb. The crushed biomass of S. cerevisiae exhibited higher Pb uptake capacity than the living S. cerevisiae and the sterilized S. cerevisiae. At the same metal concentration, metal uptake per unit concentration or adsorbent decreased when the biomass concentration rises. The order of the biosorption capacity of the living S. cerevisiae was Pb>Cu>Cd=Co>Cr. When S. cerevisiae was pretreated with 0.1 M NaOH, Pb uptake was increased by 150 percent and 0.1 M HC1, 0.1 M $H_2S_O4$ solutions were efficient in the desorption of Pb. The sorption equilibrium of Pb ions can be described by the Freundlich and Langmuir models.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.485-494
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• 1992

This study dealt with the concentration of heavy metals in mussels, Mylitus edulis and oysters, Crassostrea gigas, in different habitats around the Korean coastal waters during 1985-1989. The high levels of heavy metal concentration in two bivalves were found at Station 1, 2, 5, 23 and 25, while the low levels were found at stations in Chinhae Bay. Oysters were more effective bioaccumulators of Cu, Zn and Hg than mussels showing the ratios of 16:1 for Cu, 1.63:1 for Cd, 1.36:1 for Pb, 7.61:1 for Zn and 2.08:1 for Hg. The larger mussels were, the higher the concentrations of five metals.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.613-616
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• 2001

The effect of codopants on the electroluminescent properties for SrS-Ce based thin films was studied. The active layer was deposited by electron beam with sulfur The wavelength of eletroluminecence shifted with codopants and their concentrations. The intensity ratio of blue to green were found In the CeP-doped device, but the highest total intensity of luminance showed about 850cd/$m^2$ in the CeCl$_3$+KCL-doped device, which indicates that codopants are playing an important role of luminance. At any device, the luminance was the strongest at 0.2 mol% concentration among the concentration studied, suggesting the existence of optimum concentration. By post-annealing Luminance of most devices was improved, but the shift of wavelength was not observed.

• Journal of Preventive Medicine and Public Health
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• v.20 no.1 s.21
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• pp.49-55
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• 1987

The results of this study which had been investigated for the purpose of analyzing heavy metal concentrations in women's blood and urine, their correlation degree and significane of cadmium as indicator of accumulated heavy metals are as follows. 1) In blood, concentrations of Cd, Pb, Cu and Zn are respectively $0.0110{\pm}0.14ug/ml,\;0.308{\pm}138ug/ml,\;0.899{\pm}0.153ug/ml$ and $5.432{\pm}1.020ug/ml$. 2) In urine, concentratitons of Cd, Pb, Cu and Zn are respectively $0.003{\pm}0.12ug/ml,\;0.025{\pm}0.18ug/ml,\;0.013{\pm}0.12ug/ml$ and $0.277{\pm}0.192ug/ml$. 3) Correlation coefficients between blood and urine are only significant in Zn (r=0.363, p<0.01). 4) In blood, correlation coefficients of Cd concentration and Pb, Zn are respectively 0.518 (p<0.01). 5) Correlation coefficients between Cd concentration in blood and Pb, Cu and Zn in urine are respectively r=-0.012, r=0.027, r=0.241 (p<0.05), and only Cd concentration and Zn is significant.

• Toxicological Research
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• v.26 no.2
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• pp.157-162
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• 2010

In this study, we investigated the atmospheric heavy metal concentrations in the particulate matter inside the subway stations of Seoul. In particular, we examined the correlation between the heavy metals and studied the effect of the heavy metals on cell proliferation. In six selected subway stations in Seoul, particulate matter was captured at the platforms and 11 types of heavy metals were analyzed. The results showed that the mean concentration of iron was the highest out of the heavy metals in particulate matter, followed by copper, potassium, calcium, zinc, nickel, sodium, manganese, magnesium, chromium and cadmium in that order. The correlation analysis showed that the correlations between the heavy metals was highest in the following order: (Cu vs Zn), (Ca vs Na), (Ca vs Mn), (Ni vs Cr), (Na vs Mn), (Cr vs Cd), (Zn vs Cd), (Cu vs Cd), (Ni vs Cd), (Cu vs Ni), (K vs Zn), (Cu vs K), (Cu vs Cr), (K vs Cd), (Zn vs Cr), (K vs Ni), (Zn vs Ni), (K vs Cr), and (Fe vs Cu). The correlation coefficient between zinc and copper was 0.937, indicating the highest correlation. Copper, zinc, nickel, chromium and cadmium, which are generated from artificial sources in general, showed correlations with many of the other metals and the correlation coefficients were also relatively high. The effect of the heavy metals on cell proliferation was also investigated in this study. Cultured cell was exposed to 10 mg/l or 100 mg/l of iron, copper, calcium, zinc, nickel, manganese, magnesium, chromium and cadmium for 24 hours. The cell proliferation in all the heavy metal-treated groups was not inhibited at 10 mg/l of the heavy metal concentration. The only exception to this was with the cadmium-treated group which showed a strong cell proliferation inhibition. This study provides the fundamental data for the understanding of simultaneous heavy metal exposure tendency at the time of particulate matter exposure in subway stations and the identification of heavy metal sources. Moreover, this study can be used as the fundamental data for the cell toxicity study of the subway-oriented heavy metal-containing particulate matter.