• Korean journal of applied entomology
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• v.10 no.1
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• pp.13-22
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• 1971

This experiment was conducted to investigate the differences of the in vitro inhibitory effect of various organephobphorua insecticides on the chlinesterase from rice stem borer and those of the toxicity of them against the insect, with special references to the relationship between the cholinesterase inhibition and the toxicity. The results obtained were summarized as follows: Phosphate compounds shelved stronger inhibitory effect on the cholinesterase than thhiophosphate compounds, but was not stronger in toxicity than the latter. Diethoxy compounds were not always stronger than dimethoxy in cholinesterase inhibition and the toxicity of organophosphorus insecticides. The organophosphorus insecticides that inhibited strongly the cholinesterase were not always stronger in the toxicity.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1681-1686
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• 2014

A series of hybrid molecules between (${\alpha}$)-lipoic acid (ALA) and 4-amino-1-benzyl piperidines were synthesized and their in vitro cholinesterase (acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)) inhibitory activities were evaluated. Even though the parent compounds did not exhibit any inhibitory activity against cholinesterase (ChE) with the exception of compound 14 ($IC_{50}=255.26{\pm}4.41$ against BuChE), all hybrid molecules demonstrated BuChE inhibitory activity. Some hybrid compounds also displayed AChE inhibitory activity. Specifically, compound 17 was shown to be an effective inhibitor against both AChE ($IC_{50}=1.75{\pm}0.30{\mu}M$) and BuChE ($IC_{50}=5.61{\pm}1.25{\mu}M$) comparable to galantamine ($IC_{50}=1.7{\pm}0.9{\mu}M$ against AChE and $IC_{50}=9.4{\pm}2.5{\mu}M$ against BuChE). Inhibition kinetic studies using compound 17 indicated a mixed inhibition type for AChE and a noncompetitive inhibition type for BuChE. Its binding affinity ($K_i$) values to AChE and BuChE were $3.8{\pm}0.005{\mu}M$ and $7.0{\pm}0.04{\mu}M$, respectively.

• Journal of Environmental Science International
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• v.11 no.4
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• pp.391-397
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• 2002

This study was carried out with the inhibition of the cholinesterase activity by carbamate insecticides in the chicken in vivo and in vitro. The optimum pH of cholinesterase was 8.0. The cholinesterase activity used the acetylcholin as substrate in plasma was 24.6 $\mu$mol/min/g protein. After oral administration with 0.32 mg/kg of BPMC as carbamate pesticide, the cholinesterase activity was inhibited to 60% of control after 15min in vivo. Then the recovery of cholinesterase activity followed to 97% of control after 12hr. I$_{50}$, such as concentration required for 50% inhibition of enzyme activity, of phenyl N-methylcarbamate were 329 $\mu\textrm{g}$/$\ell$ of XMC, 214 $\mu\textrm{g}$/$\ell$ of metolcarb, 111 $\mu\textrm{g}$/$\ell$ of BPMC, 107 $\mu\textrm{g}$/$\ell$ of propoxur and 104 $\mu\textrm{g}$/$\ell$ of isoprocarb. I$_{50}$ of aromatic N-methylcarbamate were 280 $\mu\textrm{g}$/$\ell$ of carbaryl and 114 $\mu\textrm{g}$/$\ell$ carbofuran.ran.

• Journal of the Korean Chemical Society
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• v.60 no.2
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• pp.125-130
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• 2016

With the goal of developing Alzheimer’s disease therapeutics, we have designed and synthesized new triazole linked decursinol derivatives having potency inhibitory activities against cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)]. Since inhibition of cholinesterase (ChE) is still considered to be one of the most effective targets to treat AD patients, many new classes of ChE inhibitors have been synthesized. In an effort of identifying new type of cholinergic drug, decursinol derivatives 11-17 have been synthesized between decursinol and other biological interesting compounds such as lipoic acid, polyphenols, etc by using the click reaction and then evaluated their biological activities. Compound 12 (IC₅₀ = 5.89 ± 0.31 mM against BuChE) showed more effective inhibitory activity against BuChE than galantamine (IC₅₀ = 9.4 ± 2.5 mM). Decursinol derivatives can be considered a new class inhibitor for BuChE and can be applied to be a novel drug candidate to treat AD patients.

• Environmental Analysis Health and Toxicology
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• v.2 no.1_2
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• pp.17-24
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• 1987

Changes in cholinesterase (ChE) activity, electrophoretic pattern of ChE and histopathologic state on the mice serum, brain and liver by administration of organophos-phorous insecticides were studied. The mice ChE activities on serum, brain and liver decreased by increasing of concentration and time both administration of malathion and DDVP, whereas on serum and brain the activities of the 7 days after administration decreased, and then presented the gradually slight recovery in course of time. The ChE on serum and liver showed many isozyme bands by polyacrylamide gel electrophoresis but several on brain. And isozyme bands disappeared and diffused by administration of organophosphorous insecticides and development of time. The mice liver with administration group of malathion on histopathologic test showed midzonal necrosis between central vein and portal area, and with administration group of DDVP mainly presented portal necrosis on location of potal area.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3322-3326
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• 2013

A series of hybrid molecules between (${\alpha}$)-lipoic acid (ALA) and benzyl piperazines were synthesized and their in vitro cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)] inhibitory activities were evaluated. Even though the parent compounds did not show any inhibitory activity against cholinesterase (ChE), all hybrid molecules showed BuChE inhibitory activity. Some hybrid compounds also displayed AChE inhibitory activity. Specifically, ALA-1-(3-methylbenzyl)piperazine (15) was shown to be an effective inhibitor of both BuChE ($IC_{50}=2.3{\pm}0.7{\mu}M$) and AChE ($IC_{50}=30.31{\pm}0.64{\mu}M$). An inhibition kinetic study using compound 15 indicated a mixed inhibition type. Its binding affinity ($K_i$) value to BuChE is $2.91{\pm}0.15{\mu}M$.

• International Journal of Oral Biology
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• v.35 no.4
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• pp.169-175
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• 2010

Cholinesterase (ChE) is one of the most ubiquitous enzymes and in addition to its well characterized catalytic function, the morphogenetic involvement of ChE has also been demonstrated in neuronal tissues and in non-neuronal tissues such as bone and cartilage. We have previously reported that during mouse tooth development, acetylcholinesterase (AChE) activity is dynamically localized in the dental epithelium and its derivatives whereas butyrylcholinesterase (BuChE) activity is localized in the dental follicles. To test the functional conservation of ChE in tooth morphogenesis among different species, we performed cholinesterase histochemistry following the use of specific inhibitors of developing molar and incisors in the hamster from embryonic day 11 (E11) to postnatal day 1 (P1). In the developing molar in hamster, the localization of ChE activity was found to be very similar to that of the mouse. At the bud stage, no ChE activity was found in the tooth buds, but was first detectable in the dental epithelium and dental follicles at the cap and bell stages. AChE activity was found to be principally localized in the dental epithelium whereas BuChE activity was observed in the dental follicle. In contrast to the ChE activity in the molars, BuChE activity was specifically observed in the secretory ameloblasts of the incisors, whilst no AChE activity was found in the dental epithelium of incisors. The subtype and localization of ChE activity in the dental epithelium of the incisor thus differed from those of the molar in hamster. In addition, these patterns also differed from the ChE activity in the mouse incisor. These results strongly suggest that ChE may play roles in the differentiation of the dental epithelium and dental follicle in hamster, and that morphogenetic subtypes of ChE may be variable among species and tooth types.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.12-18
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• 2001

The effects of organophosphorus were examined with inhibition of the cholinesterase activity on tile chicken plasma in vivo and in vitro. The cholinesterase activity in chicken plasma determined by tile Ellman mettled was $23{\mu}mol$/min/g protein. After oral administration with 0.2 and 0.5 times of organophosphorus terbufos $LD_{50}$(1.81 mg/kg), cholinesterase activity were inhibited to 36% and 96% of control after 15min in vivo, respectively. After oral administration with 0.2 and 0.5 times of terbufos $LD_{50}$(1.81 mg/kg), then the recovery of cholinesterase activity followed to 99% and 56% of control after 11hr, respectively. Ki of phosphorodithioate and phosphorothioate with P=S was $74{\sim}322\;mole^{-1}min^{-1}$ in vitro. Ki of phosphate and phosphorothiolate with P=O was $13898{\sim}79610\;mole^{-1}min^{-1}$. Toxicology of organophosphorus with P=S was higher than that of organophosphorus with P=S by oxidation. $pI_{50}$ of phosphorodithioate and phosphorothioate with P=S was $21{\sim}102$ mg/L. $pI_{50}$ of phosphate and phosphorothiolate with P=O was $0.519{\sim}0.071$ mg/L. Enzyme-Inhibition method with cholinesterase was the rapid bioassay method to detect the organohpophorus pesticides in vitro.

• Journal of Preventive Medicine and Public Health
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• v.25 no.2 s.38
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• pp.180-188
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• 1992

The effects of multiple exposures to pesticides on plasma cholinesterase(ChE) activities and urinary p-nitrophenol excretion were evaluated in rats. Rats were received single dose i.p. with $LD_{50}/100(mg/kg)$ of organophosphorous(OP), organophosphorous-organochroline(OP-OC), organophosphorous-carbamate(OP-CAB), organophosphorous-organoarsenate(OP-OA) pesticides for 4 consecutive days. In repeated administration of pesticides, plasma ChE activities were decreased, but urinary p-nitrophenol were increased after the first injection and then decreased gradually The recovery rates of ChE activities and p-nitrophenol excretion at 48 hours after the fourth Injection were delayed in comparision with the baseline value of 24 hours before the first injection. Statistical significances were found between OP and other groups except OP-OA group after the second injection in plasma ChE activities, but in urinary p-nitrophenol excretion there was statistical significance only between OP and OP-CAB.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.265-272
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• 2002

This study was carried out with the detection for multiresidue of the organophosphorus pesticides such as malathion, parathion. diazinon, and carbamate pesticide such as carbaryl, by enzyme-inhibition method. The acetylcholinesterase (AChE) and cholinesterase (ChE) activities in chicken brain determined by the Ellman's method were 166.6 and 5.8 $\mu$mol/min/g protein, and in chicken plasma were 23.1 and 8.3 $\mu$mol/min/g protein, respectively. The optimum pH of AChE and ChE was 8.2 and 7.8, respectively. The Km of AChE and ChE was 0.034 and 0.045 mM, respectively. I$\_$50/ for AChE and ChE by some organophosphorus was 55.82 and 99.42 mg/L of malathion, 31.16 and 29.13 mg/L of parathion, and 17.89 and 19.62 mg/L of diazinon, respectively. I$\_$50/ for AChE and ChE by carbaryl of carbamate was 0.10 and 0.05 mg/L, respectively. The 0.07 mg/L of drinking water advisory level for carbaryl could be detected with I$\_$50/ of AChE and ChE. Enzyme-Inhibition (EI) method with AChE and ChE was used the multiresidue method to detect the 1 mg/L of the carbamate pesticides.