• Archives of Pharmacal Research
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• v.15 no.3
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• pp.215-219
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• 1992

S. fradiae exhibited the highest acetanilide p-hydroxylation activity among the Streptomyces spp. screened. Studies with inhibitors (metyrapone, 2. 6-dichloroindophenol, $\alpha,\alpha'$-dipyridyl, o-phenanthroline) and an absorption peak after CO treatment suggested that S. fradiae hydroxylase activity was due to cytochrome p-450. This hydroxylase activity was increased to ten times in the cell extract containing 0.5 mM sodium azide. Furthermore, the sedimentary activity in $105,000\times{g}$ centrifugal forces and solubilization of the activity with Triton-X 100 implied that this enzyme was membrane bound monooxygenase. pH Optimum of the enzyme was 6.5 in membrane bound state.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.105-115
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• 1996

In this paper, we reviewed the degradation factors of diazinon which was known to be easily degraded by soil microorganisms and lost of its activity. Under submerged soil condition, the contribution of microorganisms to diazinon degradation was about 40% and these microorganisms preferred soil humus as substrates to diazinon itself. The effect of monooxygenase activity in submerged soil was more important than esterase activity on diazinon degradation and these enzymes were inhibited by several chemicals such as piperonyl butoxide(PBO), EPN and tricyclazole. From these results, new formulation type of diazinon (PBO and triphenyl phosphate were added to commercial diazinon formulation by 0.1% respectively.) and diazinon mixture formulation (diazinon was mixed with EPN, tricyclazole and carbofuran in equal amount) were prepared. The new formulation type of diazinon showed better insecticidal activity by 12% and more delayed diazinon degradation in ten days than commercial diazinon.

• Korean Journal of Pharmacognosy
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• v.50 no.3
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• pp.159-164
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• 2019

Zanthoxylum Peel is widely used as a common spice for a variety of foods. In the orient, it has also been used as traditional agents for treating diseases such as indigestion. Recently, Zanthoxylum Peel has been reported to have anti-cancer activity, anti-microbial activity, and anti-inflammatory activity. Chemical components are known sanshool compounds and xanthoxylin. In this study, we were carried out to investigate the constituents of inhibiting a drug metabolizing enzyme CYP3A4 from Zanthoxylum Peel. CYP3A4 is known as an enzyme involved in drug metabolism as monooxygenase containing the heme. As a result of experiment, we found that bergapten ($IC_{50}=18.21{\mu}M$) and quercetin ($IC_{50}=17.27{\mu}M$) isolated from EtOAc extract of Zanthoxylum Peel showed remarkable CYP3A4-inhibiting activities. Structures of the isolated active compounds were established by chemical and spectroscopic means.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.463-467
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• 1995

In vitro metabolism study of ${\alpha}$-endosulfan by liver and kidney microsomal cytochrome P-450 monooxygenase system of the mouse(Balb/C) was performed. ${\alpha}$-Endosulfan was metabolized to endosulfan lactone(EL), endosulfan hydroxyether(EHE), endosulfan alcohol(EA), endosulfan sulfate(ES), endosulfan ether(EE) and ${\beta}$-endosulfan(${\beta}$-E). The main metabolites of ${\alpha}$-endosulfan were EL(13.2%) and EA(11.5%) in liver microsome and EA(17.4%) md EHE(19.3%) in kidney microsome. The $^{14}C$-activity of organic extractable fraction and water soluble fraction were 63.4% and 31.7% in liver micosome incubates respectively. The water soluble metabolites were EA(83.9%), EHE(4.5%) and ES(2.3). Piperonyl butoxide treatment inhibited the formation of EE by 86%, EA by 92% and EHE, EL and ES were barely formed.

• Journal of Life Science
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• v.8 no.6
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• pp.695-701
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• 1998

This study was carried out to investigate levels of the components of microsomal mixed function oxidase (MFO) system and activities of the hepatic microsomal cytochrome P45O (P45O)-dependent monooxygenases of grass snake (Natrix tigrina Lateralis) and to compare with those of rat. The levels of P45O and cytochrome b$_{5}$, (b$_{5}$) of snake were much lower than those in rat. NADPH-cytochrome c reductase activity in the snake was also only 40% of that in the rat. Activities of 7-ethoxycoumarin 0-deethylase (ECOD) and benzphetamine N-demethylase (BPDM) of snake hepatic microsomes, when compared with those of rat, were markedly low. But, aryl hydrocarbon hydroxylase (AHH) and testosterone hydroxylase (TSH) activities were nearly the same or higher than those of the rat. Of the P45O-dependent TSHs measured, 7$\alpha$-hydroxylase activity was the highest in snake, whereas, 6$\beta$-hydroxylase activity was the highest in rat. However, stereoselectivity of the enzyme from the snake to C2 and C6 positions of testoste-rone was the same as rat. The result of radioimmunoassay (RIA) for the identification of five P45O isozymes with MAbs shows that relatively high content of ethanol-inducible P45O isozyme, CYP2El, exists in the rat, whereas MC-inducible P45O isozyme, CYP2A1/1A2, does in the snake. From the analyses of SDS-PAGE and RIA of partially pu-rified P45O, we suggest the possibility of the presence of a certain P45O isozyme(s) in hepatic microsomes of snake different from those of rat.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.21-26
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• 1984

The balance between metabolic activation of xenobiotics and detoxification of their active metabolites may playa vital role in controlling mutagenic and carcinogenic processes. To assess the possible role of P. ginseng C.A. Meyer in detoxification of xenobiotics, we studied the effects of ginseng on several parameters of the monooxygenasd system, including benzo(a) pyrene monooxygenase(AHH) and benzo(a) pyrene epoxide hydratase(EH) as well as effects of ginseng on the conjugation system. Test animals receiving ginseng saponin-fraction induced epoxide hydratase activity to over $150\%$ (20mg/kg b.w.) of the control and increased glutathione transferase activity (GSH-T) up to $140\%$ (20mg/kg b.w.) of the control, whereas no significant changes were observed in the benzopyrene monooxygenase activity (AHH). Such a selective induction of the inactivation enzyme epoxide hydratase, combined with a marked elevation of the detoxifying enzyme glutathione transferase, without a concurrent induction of benzopyrene monooxygenase which is responsible for the formation of carcinogenic intermediates, demonstrates that ginseng has the potential to alter the metabolic course of carcinogenic polycyclic aromatic hydrocarbons, and thereby enhance detoxification. Thus, ginseng may play an important role in the prevention of tumors caused by carcinogens.

• Journal of Soil and Groundwater Environment
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• v.21 no.4
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• pp.50-59
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• 2016

Spatial and temporal changes in nitrification activities and distribution of microbial population of ammonia oxidizing bacteria (AOB) and ammonia oxidizing archaea (AOA) in paddy soils were investigated. Soil samples were collected in March and October 2015 from rice paddy with and without the presence of confined animal feeding operations. Incubation experiments and quantitative polymerase chain reaction showed that AOA's contribution to nitrification kinetics was much higher in locations where organic nitrogen in animal waste is expected to significantly contribute to overall nitrogen budget, and temporal variations in nitrification kinetics were much smaller for AOA than AOB. These differences were interpreted to indicate that different microbial responses of two microbial populations to the types and concentrations of nitrogen substrates were the main determining factors of nitrification processes in the paddy soils. The copy numbers of ammonium monooxygenase gene showed that AOA colonized the paddy soils in higher numbers than AOB with stable distribution while AOB showed variation especially in March. Although small in numbers, AOB population turned out to exert more influence on nitrification potential than AOA, which was attributed to higher fluctuation in AOB cell numbers and nitrification reaction rate per cells.

• Journal of Life Science
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• v.12 no.5
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• pp.561-565
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• 2002

Pseudomonas sp. EL-041 was previously isolated from phenol-acclimated activated sludge. This bacterium was capable of degrading phenol and cometabolizing trichloroethylene (TCE). In this study, we report the identification of trichloroethylene- degrading enzyme in Pseudomonas sp. EL-041 by the investigation of enzyme activity and DNA sequencing of specific phenol oxygenase gene. As the results of experiment, trichloroethylene-degrading enzyme in Pseudomonas sp. EL-041 was monooxygenase and suspected to phenol hydroxylase.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.511-518
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• 2006

A gene cluster for cyclohexanone oxidation was cloned from Rhodococcus sp. TK6, which is capable of growth on cyclohexanone as the sole carbon source. The 9,185-bp DNA sequence analysis revealed seven potential open reading frames (ORFs), designated as ssd-chnR-chnD-chnC-chnB-chnE-partial pcd. The chnBCDE genes encode enzymes for the four-step conversion of cyclohexanone to adipic acid, catalyzed by cyclohexanone monooxygenase (ChnB), $\varepsilon-caprolactone$ hydrolase (ChnC), 6-hydroxyhexanoate dehydrogenase (ChnD), and 6-oxohexanoate dehydrogenase (ChnE). Furthermore, the presence of a regulatory element in the downstream region of the chnD gene supports the notion that chnR is a putative regulatory gene. Among them, the activity of ChnB was confirmed and characterized, following their expression and purification in Escherichia coli harboring the modified chnB gene (chnB gene with 6 successive codons for His at the 3' terminus).

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.47-55
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• 2014

Arthrobacter chlorophenolicus A6 possesses several monooxygenases (CphC-I, CphC-II, and CphB) that can catalyze the transformation of 4-chlorophenol (4-CP) to hydroxylated intermediates in the initial steps of substrate metabolism. The corresponding genes of the monooxygenases were cloned, and the competent cells were transformed with these recombinant plasmids. Although CphC-II and CphB were expressed as insoluble forms, CphC-I was successfully expressed as a soluble form and isolated by purification. The specific activity of the purified CphC-I was analyzed by using 4-CP, 4-chlorocatechol (4-CC), and catechol (CAT) as substrates. The specific activities for 4-CP, 4-CC, and CAT were determined to be 0.312 U/mg, 0.462 U/mg, 0.246 U/mg, respectively. The results of this study indicated that CphC-I is able to catalyze the degradation of 4-CC and CAT in addition to 4-CP, which is a primary substrate. This research is expected to provide the fundamental information for the development of an eco-friendly biochemical degradation of aromatic hydrocarbons.