• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.125-137
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• 2020

In recent years, toxic organophosphorus compounds (OPs) have been used for civilians, becoming a great threat to the world. Alternative to the current treatment policy unpredictable for any prevention, researches on bioscavenger as an improved treatment have been actively conducted. Bioscavengers refer to proteins and enzymes that prevent intoxication by inactivating or binding toxic OPs before they reaches the target. In particular, extensive efforts have been made to develop catalytic bioscavengers that quickly detoxify OPs even with a small dose of the protein by performing multiple binding and hydrolysis processes with OPs. This review introduces the latest studies and results for developing catalytic bioscavengers using molecular evolution and protein engineering techniques. We will briefly present some of the remaining challenges on developing enzymes into clinically approved drugs.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.513-522
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• 2019

Catalysts based on organic compounds, transition metal and metal-organic frameworks (MOFs) have been applied to degrade or remove organophosphorus toxic compounds (OPs). During the last 20 years, various MOFs were designed and synthesized to suit application purposes. MOFs with $Zr_6$ based metal node and organic linker were widely used as catalysts due to their tunability for the pore size, porosity, surface area, Lewis acidic sites, and thermal stability. In this review, effect on catalytic efficiency between MOFs properties according to the structure, stability, particle size, number of connected-ligand, organic functional group, and so on will be discussed.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.108-113
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• 1998

Egasyn is accessory protein of ${\beta}$-glucuronidase(${\beta}$-G) in the liver microsomes. Liver microsomal ${\beta}$-G is stabilized within the luminal site of the microsomal vesicles by complexation with egasyn which is one of carboxylesterase isozymes. We investigated the effects of organophosphorus compounds(OPs) such as insecticides on the dissociation of egasyn-${\beta}$-glucuronidase(EG) complex. The EG complex was easily dissociated by administration of OPs, i.e., Fenitrothion, EPN, Phenthionate, and bis-p-nitrophenyl phosphate(BNPP), and resulting ${\beta}$-G dissociated was released into blood, leading to the rapid and transient increase of plasma ${\beta}$-G level with a concomitant decrease of liver microsomal ${\beta}$-G level. In a case of phenthionate treatment, less increase in plasma ${\beta}$-G level was observed, as compared with those of other OPs. This may be explained by a fact that phenthionate was easily hydrolyzed by carboxylesterase. Similarly, carbamate insecticides such as Carbaryl caused rapid increase of plasma ${\beta}$-G level. In contrast, no significant increase of plasma ${\beta}$-G level was observed when pyrethroid insecticides were administered to rats. This is due to a fact that pyrethroids such as Phenthrin and Allethrin were easily hydrolyzed by A-esterase as well as carboxylesterase. On the other hand, addition of OPs to the incubation mixture containing liver microsomes caused the release of ${\beta}$-G from microsomes to the medium. From these in vivo and in vitro data, it is concluded that increase of the plasma ${\beta}$-G level after OPs administration is much more sensitive biomarker than cholinesterase inhibition to acute intoxication of OPs and carbamates.