• Journal of Environmental Science International
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• v.19 no.12
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• pp.1335-1341
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• 2010

Voltammetric diagnostics of pesticide thiram was studied in plant leafs in vivo fluid with DNA immobilized on a carbon nanotube electrode (DCE). Sensor properties of carbon nanotube (CE) and DNA immobilized nanotube were compared. DCE was more effective than CE in target detecting. The parameters such as pH strength, stripping accumulation, amplitude, and increment potential were examined to find the optimum condition for detection of pesticide thiram in a sesame leaf. The optimized conditions were as follows 550 Hz frequency, 0.15 V amplitude, 0.005 V increment potential, -1.2 V initial potential, 4.78 pH, 500 sec accumulation time. Under optimum condition, the detection limit of thiram was attained at 0.01ng/L.

• Environmental Engineering Research
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• v.14 no.4
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• pp.226-236
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• 2009

The performance of phytoremediation has proven effective in the removal of nutrients and metals from aqueous systems. However, little information is available regarding the behavior of pesticides and their removal pathways in aquatic environments involving plant-uptake. A detailed understanding of the kinetics of pesticide removal by plants and information on compound/plant partition coefficients can lead to an effective design of the phytoremediation process for anthropogenic pesticide reduction. It was determined that the reduction rates of four organophosphorus (OP) and two organochlorine (OC) pesticides (diazinon, fenitrothion, malathion, parathion, dieldrin, hexachlorobenzene [HCB]) could be simulated by first-order reaction kinetics. The magnitude of k was dependent on the pesticide species and found within the range of 0.409 - 0.580 $d^{-1}$. Analytical results obtained by mass balances suggested that differential chemical stability, including diversity of molecular structure, half-lives, and water solubility, would greatly influence the removal mechanisms and pathways of OPs and OCs in a phytoreactor (PR). In the case of OP pesticides, plant accumulation was an important pathway for the removal of fenitrothion and parathion from water, while pesticide sorption in suspended matter (SM) was an important pathway for removal of dieldrin and HCB. The magnitude of the pesticide migration factor (${\Large M}_p^{pesticide}$) is a good indication of determining the tendency of pesticide movement from below- to above-ground biomass. The uncertainties related to the different phenomena involved in the laboratory phyto-experiment are also discussed.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.255-263
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• 1993

The demand of safety assessment for pesticide residues in foods is growing in Korea. In order to assess the actual dietary exposure toward pesticide residues, the problems in utilization of pesticide residue data were reviewed and optimization of food factors applicable to Korean population was conducted. The problems and current status in setting pesticide residue tolerance-domestic and foreign-in foods were also argued. The conclusion is summarized as follows: (1) Anticipated residue estimates(ARE) calculated from field trial residue data, the percentage of crop treated, and the effects of cooking or processing should be utilized for dietary exposure assessment in a real sense. (2) Average daily intake of total foods per person in Korea was 1,104g in 1970's and 1,240g in 1980's. Much variation was observed between the two decades by food commodities. (3) Pesticide residue tolerances in Korea have been established at relatively lower levels in comparison with FAO/WHO or western countries. More extensive studies and data accumulation as related to tolerance setting are called for in future for the sake of health protection and smooth interstate trade.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.1-20
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• 1998

Chlorsulfuron, one of sulfonylurea herbicides acts through inhibition of acetolactate syuthase (EC 4.1.3.18; ALS, also known as acetohydroxyacid synthase) in the branched-chain amino acid biosynthesis process. After chlorsulfuron-ALS interaction, many physiological and metabolic disruptions occur in plants. However, it is not clear how this chlorsulfuron-ALS interaction affects those physiological and metabolic processes and how this interaction leads subsequently to plant death. Several researchers suggested that the death of chlorsulfuron-treated plants might be due to a shortage of the branched-chain amino acids, an accumulation of toxic metabolites, and/or a depletion of photoassimilates. It remains as a mystery presently, however, if such changes result in the plant death. In this review, we discussed how the chlorsulfuran-ALS interaction leads to physiological and metabolic disruptions in plants.

• Journal of Applied Biological Chemistry
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• v.56 no.2
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• pp.109-112
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• 2013

Azole fungicides are one of the most wide-spread antifungal compounds in agriculture and pharmaceutical applications. Their major mode of action is the inhibition of ergosterol biosynthesis, giving depletion of ergosterol, precursors and abnormal steroids. However, metabolic consequences of such inhibition, other than steroidal metabolitesare not well established. Comprehensive metabolic profiles of Saccharomyces cerevisiae has been presented in this study. Wild type yeast was treated either with glucose as control or azole fungicide (ketoconazole). Both polar metabolites and lipids were analyzed with gas chromatography-mass spectrometry. Approximately over 180 metabolites were characterized, among which 18 of them were accumulated or depleted by fungicide treatment. Steroid profile gives the most prominent differences, including the accumulation of lanosterol and the depletion of zymosterol and ergosterol. However, the polar metabolite profile was also highly different in pesticide treatment. The concentration of proline and its precursors, glutamate and ornithine were markedly reduced by ketoconazole. Lysine and glycine level was also decreased while the concentrations of serine and homoserine were increased. The overall metabolic profile indicates that azole fungicide treatment induces the depletion of many polar metabolites, which are important in stress response.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1050-1053
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• 2000

Biological evaluation of residual malathion after 168 hrs of single dipping exposure of White Leghorn hens to different concentrations (0, 0.5, 1.0 and 1.5%) of pesticides was investigated. Thirty-two male albino rats divided into four groups of eight each were kept on 20% isoproteinous diet prepared from the meat of these malathion dipped hens. After 30 days feeding trial, the rats were killed by decapitation. No significant change was found in erythrocytes. However, the triglyceride concentration in brain tissue was increased significantly (p<0.05) when dose level of pesticide was 1% in dipping solution. Similarly, malathion exposed poultry meat failed in altering any significant change in the pancreatic amylase and lipase activities of rats. This study concludes the virtual absence of toxic accumulation of pesticide in the meat of birds after 168 hrs of exposure in usual concentration range upto 1.5%.

• Journal of Ginseng Research
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• v.48 no.1
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• pp.98-102
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• 2024

Background: Ginseng (Panax ginseng Meyer) is a perennial plant belonging to the Araliaceae family that is known to have various beneficial effects including improving memory loss and spatial cognitive ability, and anti-cancer and anti-diabetes activity. Its functional benefits also include improving liver function, regulating blood pressure, stress, and providing antioxidant activity. Usually, various agrochemicals are used in cultivating ginseng preventing from many diseases. Methods: FCGP (field cultivated ginseng in pot) was implemented by imitating MCWG (mountain cultivated wild ginseng). Pesticide analysis of pot cultivation was carried out and the contents of bioactive components such as ginsenoside were also analyzed. Results: FCGP ginsenoside content was higher than that of FCG (field cultivated ginseng) and MCWG. FCGP has been shown to have a relatively high antioxidant effect compared with cultivated ginseng. Conclusion: It was confirmed that ginseng can be grown for 6 years without resorting to use of pesticides. In addition, it was confirmed that effective accumulation of physiologically active ingredients such as ginsenoside is possible. Our result represents FCGP is a novel method of pesticide-free ginseng cultivation

• Journal of the Korean Society of Urban Environment
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• v.18 no.4
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• pp.391-399
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• 2018

In this study, Diazinon which is the most widely used organophosphorus pesticides (OPPs) among pesticides was removed by ozone/hydrogen peroxide advanced oxidation process (Peroxone AOP). Diazinon is mainly found in groundwater, drinking water, rivers and ponds that are near agricultural areas using the pesticide. Accumulation of Diazinon on the body in the form of metabolites causes neurotoxicity, confusion, dizziness and vomiting. Diazinon is not easily removed by conventional water treatment processes. This study investigated the Diazinon removal characteristics with OH radicals with strong oxidizing power generated by using ozone and hydrogen peroxide. We determined optimal hydrogen peroxide/ozone injection molar ratio and confirmed the elimination reaction to initial Diazinon concentration, pH and DOC concentration, which are factors influencing the removal efficiency. Domestic researches on pesticide removal in the environment are much less than the cases of overseas. This study is expected to provide a basis for the process design for pesticide removal.

• Journal of Environmental Science International
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• v.8 no.1
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• pp.19-26
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• 1999

The degree of pesticides accumulation in tap water in Taejon from June 1995 to Apr 1996 was measured by Ellman's coupled enzyme assay. Since organic phosphate and carbamate pesticides specifically inhibit the neurotransmitter modulating enzyme acetylcholinesterase(AChE), the enzyme activity can be used as a diagnosis for the pesticides accumulation in water and various samples. During the period of this study, the enzyme activity was changed almost every week. The lowest enzyme activity was 64 % of that of the control reaction and there are several days showing about 100 % enzyme activity. In general, the enzyme activity is higher in summer than other seasons especially early spring times. The pH value of tap water was very close to neutral(pH 7.0) and it seems that the enzyme activity was not affected by the small pH changes. Either boiling of tap water or addition of NaOH solution decomposed the pesticide components. These results show that AChE assay is a convenient, sensitive, and reliable method for detection of pesticides in water samples.

• Analytical Science and Technology
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• v.15 no.6
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• pp.489-495
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• 2002

In this study, we determined distribution status of organonitrogen pesticides such as trifluralin, atrazine, metribuzin, alachlor, malathion, nitrofen, permethrin, cypermethrin, fenvalerate, and parathion accumulated in the fresh water fishes and amphibians. We collected those samples at 31 sites from the basin of major rivers, and separated the muscular tissue as a final sample for analysis. In the pretreatment process, lipid was eliminated by using acetonitrile and n-hexane, and pesticides were reextracted with dichloromethane. The extract was dehydrated and concentrated, and then cleaned it up by passing the Florisil column, and pesticide content was finally determined by using a GC-MS system after introducing isotope labelled references. The accumulation level was observed in the range of $0.17{\sim}6.8{\mu}g/kg$ in amphibians and $0.26{\sim}16{\mu}g/kg$ in fishes including cypermethrin as $16{\mu}g/kg$.