4-Methyl-5-nitrocatechol (4M5NC) monooxygenase (DntB) from Burkholderia sp. strain DNT catalyzes the second step of 2,4-dinitrotoluene degradation by converting 4M5NC to 2-hydroxy-5-methylquinone with the concomitant removal of the nitro group. DntB is a flavoprotein that has a very narrow substrate range. Here, error-prone PCR was used to create variant DntB M22L/L380I, which accepts the two n...

OBJECTIVES The aim of this study was to evaluate the effect of hypothermia on the in-vivo pharmacokinetics of 4-nitrophenol (4NP) using rat liver homogenate and rat liver perfusion system. METHODS Rat liver homogenate was incubated with 4NP, which is mainly metabolized by cytochrome P450 2E1, at 37, 34, 32 or 28°C. The Michaelis constant (Km ) and maximum elimination velocity (Vmax ) of 4NP w...

In order to investigate nitro-substitutent's effect on degradation of phenols at boron-doped diamond (BDD) anodes, cyclic voltammetries of three nitrophenol isomers: 2-nitrophenol (2NP), 3-nitrophenol (3NP) and 4-nitrophenol (4NP) were studied, and their bulk electrolysis results were compared with phenol's (Ph) under alkaline condition. The voltammetric study showed nitrophenols could be attac...

ABSTRACT: In this project, a nano catalyst (TiO2) and ozone combined with each other and they were used for the removal of 4-nitrophenol (4NP) in industerial wastewater. The effect of some operational parameters such as initial pH (3-9), the concentration of pollutant (20-80 mg/L), and amount of TiO2 were investigated. In O3/TiO2 process, the anion radical  formed before the production of hydro...

ABSTRACT: In this project, a nano catalyst (TiO2) and ozone combined with each other and they were used for the removal of 4-nitrophenol (4NP) in industerial wastewater. The effect of some operational parameters such as initial pH (3-9), the concentration of pollutant (20-80 mg/L), and amount of TiO2 were investigated. In O3/TiO2 process, the anion radical  formed before the production of hydro...

abstract: in this project, a nano catalyst (tio2) and ozone combined with each other and they were used for the removal of 4-nitrophenol (4np) in industerial wastewater. the effect of some operational parameters such as initial ph (3-9), the concentration of pollutant (20-80 mg/l), and amount of tio2 were investigated. in o3/tio2 process, the anion radical  formed before the production of hydro...

The combination of sonolysis and ozonolysis as an advanced oxidation process was investigated to gain insight into factors affecting enhancement of the combined system. Sonolysis, ozonolysis, and a combination of the two were used to facilitate the degradation of three known organic contaminants, nitrobenzene (NB), 4-nitrophenol (4NP), and 4-chlorophenol (4-CP), in water. Experiments were perfo...

The present study has provided a comparison between a conventional ex situ method for the treatment of contaminated soil, a soil slurry bioreactor, with a novel technology in which a contaminant is rapidly and effectively removed from the soil by means of absorptive polymer beads, which are then added to a two-phase partitioning bioreactor (TPPB) for biodegradation of the target molecule. 4-nit...

this research evaluates the efficiency of nanosized zno in the catalytic ozonation of 4-chloro-2-nitrophenol and determines the effect of ph on heterogeneous catalytic ozonation. the combined use of ozone and zno catalyst leads to conversion of 98% 4-chloro-2-nitrophenol during 5 min. in addition, it was found that in zno catalytic ozonation, the degradation efficiency of 4-chloro-2-nitrophenol...