• Bulletin of the Korean Chemical Society
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• v.21 no.5
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• pp.471-476
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• 2000

Liquid chromatography/mass spectrometry with an atmospheric pressure chemical ionization interface (LC/APCI/MS) is evaluated for the simultaneous determination of carbamate pesticides and organophosphorus pesticides in a single chromatographic analysis. APCI mass spectra of those compounds were obtrained to study their ionization characteristics. APCI provided abundant ions such as protonated molecules and characteristic fragment ions for carbamate pesticides and organophosphorus pesticides. To evaluate the feasibility of the LC/APCI/MS for a routine quantitative analysis, the linearity and repeatability of LC/APCI/MS were examined by measuring standard solution mixtures of five carbamate pesticides and four organophosphorus pesticides over the range of 1 to 100 ㎍/mL. Teh peak areas in chromatograms of characteristic ions for those compounds showed less than 3% of variation from run to run. The standard calibration curves for the nine pesticides show good linearity in the concentration range. The detection limits of the LC/APCI/MS system for those compounds range from 0.006 to 0.2 ng.

• Research in Plant Disease
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• v.18 no.3
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• pp.175-185
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• 2012

The problems caused by synthetic pesticides have led the need for effective biodegradable pesticides with greater selectivity. Botanical pesticides are generally recognized as safe in agriculture systems. Thus, they have been regarded as attractive alternatives to synthetic chemical pesticides for the pest management. Both lower efficacy and higher costs of production make botanicals more expensive to use than conventional pesticides. Moreover, only a small portion of plant-derived metabolites among a number of bioactive metabolites are in use because commercialization of botanicals is inhibited by several problems such as toxicity, or high production cost. However, with the growing acceptance of botanical pesticides as an efficient crop protection alternative resulting in increasing demand, plant-based pesticides will play a significant role in achieving sustainable agriculture in future.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1586-1592
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• 2012

A series of Novel Mannich bases has been synthesized and evaluated $in$ $vitro$ cytotoxic activity against the human hepatocellular carcinoma (HepG2), human lung carcinoma (SK-LU-1), and human breast cancer (MCF-7). Compound $\mathbf{9f}$ was found to be most potent against three cell lines with $IC_{50}$ values of 1.57, 1.16 and 1.21 ${\mu}g$/mL, respectively. In addition, compounds $\mathbf{9g}$, $\mathbf{10f}$ exhibited very significant activity against MCF-7 cell line with $IC_{50}$ values of 2.0 ${\mu}g$/mL.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.537-544
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• 2007

This study was carried out to investigate adsorption characteristics of residual pesticides on an adsorbent. $Bauxsol^{TM}$ and mackban-stone as adsorbent were used. Analytical method for residual pesticides was established by GC/NPD and $GC/{\mu}ECD$. Pesticides used in this study were ${\alpha}$-endosulfan, ${\beta}$-endosulfan, pendimethalin and chlorpyrifos-methyl, fenitrothion, and recovery rates were more than 97%. Adsorption rate on an adsorbent was decreased in order of endosulfan, chlorpyrifos-methyl, pendimethalin, fenitrothion. Organochlorine pesticides showed higher removal rate than the other pesticides. $Bauxsol^{TM}$ gave both chemical decomposition and physical adsorption. Mackban-stone gave only physical adsorption on the other hand. The high pH and chloric ions structure of eluted solution have greatly affected at chemical resolution. The removal rate of pesticides was increased due to the physical property of adsorbent, i.e. high porosity. The above adsorbent is to be a candidate to remove residual pesticides in water and pond of links.

• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.84-97
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• 1983

Under the limited arable land, the enhancement of agricultural productivity is indispensable to provide the food demand which is concomitant with the rapid increase in population. From this viewpoint, the upbringing and dissemination of high-yielding varieties has been promoted continuously and several modifications in cultural practices, including heavy fertilization, dense planting, and early transplanting, also have been gradually developed. However these changes in cultivation have led to the increased outbreak of insect pests and diseases. And this unexpected results have accelerated the number and complexity of pesticides employed as well as their consumption. Even though pesticides are essential materials contributing to the steady production of agricultural crops, large scale consumption of them has given rise to several adverse impacts, such as mammalian hazard and/or environmental contamination. In this respect, recent development of new pesticides has been concentrated on 'safe pesticide', as it were, that has the highly selective properties without unfavorable side influences on other ecosystem. According to literature cited up to now, feasibilities of safe pesticide development would be summarized as two categories. One of them is the development of chemical pesticides, which include the molecular structure modification of established pesticides for increased safety and synthesis of new safe chemicals which can attack the vulnerable point of physio-ecological characteristics in insect pests and diseases. The other is the biological pesticides which comprise natural enemies and microorganisms to act selectively on confined insect pests and diseases, In addition, improvement of physico-chemical properties of available pesticide formulations would be one of the desirable means for safe pesticide development in view of efficacy enhancement and minimization of hazardous properties or safe pesticide development, various approaches are feasible and needed to study, however, long period and much financial outlay are necessary to develop a new item. And under the present situation in Korea, there are many difficulties for performing research on all the possible routes. Therefore, combined pesticides by the reasonable combination of already registered resticides evaluated as the fairly safe pesticides and safe formulation based on their physico-chemical properties would be developed primarily. And many efforts would be given gradually for the development of new chemical and biological pesticides.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.560-568
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• 1991

The simultaneous determination method which simply determined regulated pesticides was investigated. Sample was extracted with acetone-methanol and partitioned with methylene chloride after addition of saturated NaCl solution. Entract was purified by Bio-Beads S-X3 column using cyclohexane-methylene chloride (1 : 1) as eluate. The determination of pesticides was performed by BP-1 capillary column gas chromatography using ECD and NPD. The average recoveries of pesticides in rice and soy fbean were over 83% and 81%, respectively. It was possible to detect pesticides in rice up to 0.002 ppm by $\alpha-BHC$ and up to 0.05 ppm by carbaryl and in soy bean up to 0.01 ppm by ${\alpha}$-BHC and up to 0.3 ppm by carbaryl.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.344-344
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• 2009

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.11-20
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• 2012

As increasing the use of pesticides both in number and amount to boost crop production, consumer concerns over food quality and safety with respect to residual pesticides are also continuously increasing. However, there is still lacking of information that can effectively help to remove residual pesticides in foods. In recent years, contaminant removal by gas (or) glow discharge plasma (GDP) attracts great interests on environmental scientists because of its high removal efficiency and environmental compatibility. It was shown to be effective for the removal of some organophosphorus pesticides, phenols, benzoic acid, dyes, and nitrobenzene on solid substrate or in aqueous solution. This work mainly focuses on the removal of wide range of residual pesticides from fresh fruits and vegetables. As for preliminary study, the experiments were carried out to investigate whether GDP can be used as an effective tool for degrading target pesticides or not. With this objective, 60 selected pesticides drop wised onto glass slides were exposed to two types of GDP, dielectric barrier discharge plasma (DBDP) and low pressure discharge plasma (LPDP), for 5 min. Then, they were washed with 2 mL MeCN which were collected and used for determination of remaining concentration of pesticides using LC-MS/MS. Among selected pesticides, degradation of 18 pesticides (endosulfan-total was counted as one pesticide) by GDP could not be examined because control treatments, which were left in ambient environment, of those pesticides recovered less than 70% or even did not recover. However, majority of tested pesticides (42) were degraded by both types of GDP with satisfactory recovery (>80%) of control sample. Pesticides degradation ranged from 66.88% to 100% were achieved by both types of plasma except clothianidin which degradation in LPDP was 26.9%. The results clearly indicate that both types of gas discharge plasma are promising tools for degrading wide range of pesticides on glass substrate.

• Korean Journal of Weed Science
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• v.17 no.1
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• pp.112-123
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• 1997

Chemical pesticides have been re used for a long time to protect crops from diseases, insects, and weeds ; ample and secure supply of foods in present days would not be possible without them. However, concerns on the risk of using chemical pesticides rising steadily in recent years forced discard many of them and seek an alternate, environment-friendly control strategies. Microbial pesticide is regarded as one of the most promising methods because if properly developed, it will be effective, cheap, and environment-safe. Currently, about 180 microbial pesticides are under development throughout the world and at least 20 of them including B.t. and antibiotics are registered in Korea. This paper discusses some of the successful examples, intriguing problems, and future prospects of microbial pesticides.

• The Korean Journal of Zoology
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• v.20 no.1
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• pp.19-28
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• 1977

In order to evaluate the mutagenic potential in animal for these pesticides which were proved to be mutagenic in the bacterial screening system with a metabolic activation in vitro, we have studied in vivo cytogenetic effects on mouse bone marrow by means of the micronucleus test. The clastogenic activity of the chemical is evaluated as the frequency of micronuclei in polychromatic erythrocytes. We have tested six pesticides, insecticides, DDVP and trichlorfon, fungicide, TMTD, herbicides, NIP and MO and growth regula색, maleic hydrazide. It was found that among the tested pesticides only TMTD exhibited minimal activity in inducing micronuclei. Organophosphorus insecticide DDVP that is the most broadly used and economically important chemical, did not increase the micronuclei frequencies in mouse bone marrow cells as with the all other pesticides tested.