• Korean Journal of Pharmacognosy
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• v.34 no.1 s.132
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• pp.14-17
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• 2003

In the course of screening Korean natural plants for acetylcholinesterase (AChE) inhibitory activity, we found that a methanolic extract of the leaves of Securinega suffruticosa showed significant inhibitory effects on AChE. Bioassay-guided fractionation of the methanolic extract resulted in the isolation of dihydrosecurinine, as a active principle. This compound inhibited AChE activity in a dose-dependent manner, and the $IC_{50}$ value of dihydrosecurinine was $18.9\;{\mu}g$.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.185-188
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• 2010

• Applied Biological Chemistry
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• v.38 no.2
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• pp.174-178
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• 1995

The purpose of this study was to investigate a role of cytochrome $P_{450}$, for the toxicity of the phosalone in in vitro and in vivo bioactivation systems. The bimolecular inhibition rate constants$(k_i)$ of the phosalone to acetylcholinesterase(AChE) and butyrylcholinesterase(BuChE) were approximately $10^2M^{-1}{\cdot}min^{-1}$, respectively, which meant a poor inhibitor. The potency of the phosalone as an inhibitor of AChE and BuChE was increased about 300 and 40 fold, respectively, when the inhibitor and the ChE were incubated with microsomes fortified with NADPH compared with microsome alone. Piperonyl butoxide(PB) addition to these coupled systems greatly reduced the inhibition of both target enzymes by blocking a bioactivation process. The $I_{50}$ value of the Phosalone alone for rat brain AChE was 170 mg/kg. When PB was pretreated, that value was altered to 42.5 mg/kg. PB pretreatment synergized the inhibition of brain AChE with four times. Rat blood erythrocyte AChE and plasma BuChE were similarly inhibited in vivo by the phosalone and PB pretreatment didn't affect significantly the pattern of the inhibition. The in vivo studies showed different results in the role of cytochrome $P_{450}$ from those of the in vitro studies.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.215-219
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• 2002

Over the past decade there has been a resurgence of interest in botanical products for their medicinal uses. This present study was designed to screen medicinal plants for the treatment of brain diseases such as Alzheimer's disease or aging. We tested the effects of the water extracts from 41 species medicinal plants on acetylcholinesterase (AChE) inhibition and antioxidant activity in vitro. Among them, Euodia rutaecarpa, Rubus coreanus, Achyranthes japonica, Morus alba, Salvia miltiorrhiza, Liriope platyphylla, and Rheum palmatum showed relatively AChE inhibition potency over 80%. Among the 7 medicinal plants investigated, E. rutaecarpa showed an 25%, 65%, and 93% inhibitions on AChE activity at 2.5, 12.5, and 25 ㎍/㎖ of the extract, respectively and was found to be one of most potent AChE inhibitor. The water extracts from 4 species (E. rutaecarpa, R. coreanus, A. iaponica, and M. alba) were tested on their antioxidant capacities using radical scavenging effect against ABTS/sup ㆍ+/. Among the 4 medicinal plants investigated, both R. coreanus and E. rutaecarpa showed significant antioxidant capacity. Therefore, E. rutaecarpa and R. coreanus are expected to ameliorate the clinical symptoms in Alzheimer's disease due to significant AChE inhibition and radical scavenging effect.

• KSBB Journal
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• v.17 no.2
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• pp.158-161
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• 2002

In this study, a prototype fiber-optic biosensor was fabricated using the inhibition of enzyme reaction by organophosphorus compounds to detect organophosphorus compounds, which is nervous toxic material an? is used as chemical weapon and pesticide. Enzyme, substrate, and inhibitor for enzyme reaction were acetylcholinesterase (key enzyme in nervous cell), acetylthiocholine iodide, and paraoxon (a kind of organophosphorus compounds), respectively. The detection principle of sensor is the detection of enzyme reaction inhibited by organophosphorus compounds by the quantitative measurement of acetic acid, which was achieved by absorbance measurement using litmus solution that maximum absorbance band is changed by pH. To fabricate prototype fiber-optic biosensor, high bright LED and photodiode was used as light source and light intensity detector, respectively. From the experimental results using a prototype biosensor, the linear change of sensor signal was obtained in a range of 0-2 ppm inhibitor concentrations. From these results, it was verified that the quantitative measurement of organophosphorus compounds could be achieved fast (within 2 minutes) and accurately by a prototype fiber-optic biosensor.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.384-388
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• 2008

Alzheimer's disease (AD) is the most common neurodegenerative disorder and is responsible for more than 50% of all dementia cases. There is significant interest in finding new sources of compounds that inhibit acetylcholinesterase (AChE) to be used in the treatment of AD, since only a few AChE inhibitors, such as galanthamine, physostigmine, and tacrine, are available for clinical use. In the present study, ICR mice were treated with a 1 mg/kg scopolamine, which caused impaired cognitive ability. The steady consumption of a water extract of Chrysanthemum indicum Linne flowers for 3 months significantly prevented the scopolamine induced deficit of the spatial cognitive capability of mice. It also improved long-term memory in mice with amnesia induced by scopolamine, as assessed by the Morris water maze and passive avoidance tests. In addition, water extract consumption significantly decreased AChE activity in mouse brain, leading to inhibition of acetylcholine hydrolysis.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.265-269
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• 2007

There is significant interest in finding new sources of acetylcholinesterase (AChE) inhibitors for use in treating Alzheimer's disease, since only a few AChE inhibitors are available for clinical use, such as galanthamine, physostigmine, and tacrine. The ethanol extract of Chrysanthemum indicum Linne flowers was analyzed and found to markedly decrease AChE activity. Acaciin and $acacetin-7-O-{\beta}-D-galactopyranoside$ were identified as the active compounds responsible for the AChE inhibition by using an activity-guided fractionation strategy. The relationship between structure and activity for five flavonoids (acaciin, $acacetin-7-O-{\beta}-D-galactopyranoside$, luteolin, and two other commercially available flavonoids, i.e., apigenin and acacetin) was also investigated, revealing that the presence of methoxy groups at C-4' in the B ring and a sugar at O-7 in ring A appear to be essential for the inhibition of AChE.

• The Korean Journal of Food And Nutrition
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• v.24 no.2
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• pp.153-158
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• 2011

This study was performed to develop new anti-obesity agents from medicinal plants for functional food industry. We prepared lipase inhibitor-containing ethanol extracts from Desmodium oxyphyllu DC. and its nutritional characteristics, stability of temperature and pH and physiological functionalities were investigated. Crude lipid content and curde protein content of ethanol extract from Desmodium oxyphyllum DC. were 26.5% and 5.7%, respectively and its asparagine content was 4,860 mg/100 g, dry basis. The ethanol extracts were also stable from pH 3.0 to pH 9.0 and below $80^{\circ}C$. The ethanol extract were showed high lipase inhibitory activity of 74.2% and acetylcholinesterase inhibitory activity of 68.4%.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.438-443
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• 1991

This study was designed to examine the effects of diphenhydramine and papaverine on the toxic manifestations of cholinesterase inhibitors. It was found that papaverine increase acetylcholinesterase activity in cerebral cortex of mice. Papaverine pretreatment tended to increase acetylcholinesterase activity against the actions of neostigmine and physostigmine. When diphenhydramine (20~30 mg/kg, s.c.) was treated 20 min before the administration of cholinesterase inhibitor, it significantly extended the onset latency in the signs of toxicosis which were characteristically produced by physostigmine (0.25~1.5 mg/kg, s.c.) or neostigmine (0.125~0.5 mg/kg, s.c.), and it also prevented lethality in all of the animals.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.387-391
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• 2009