The aromatic hydrocarbon biphenyl is a widely distributed environmental pollutant. Whereas the aerobic degradation of biphenyl has been extensively studied, knowledge of the anaerobic biphenyl-oxidizing bacteria and their biochemical degradation pathway is scarce. Here, we report on an enrichment culture that oxidized biphenyl completely to carbon dioxide under sulfate-reducing conditions. The ...

Aqueous dispersions of graphene oxide (GO) have been found to emit a structured, strongly pH-dependent visible fluorescence. Based on experimental results and model computations, this is proposed to arise from quasi-molecular fluorophores, similar to polycyclic aromatic compounds, formed by the electronic coupling of carboxylic acid groups with nearby carbon atoms of graphene. Sharp and structu...

abstract low molecular weight carboxylic acids (lmw) play an important role in improving the bioavailability of soil nutrients. nonexchangeable soil k, trapped between the interlayers of clay minerals, is an important source of k for plants in many soils. the objectives of this study were to determine the effect of selected lmw organic acids on the release of k from micaceous minerals and to in...

The fluorescent derivatization of aromatic carboxylic acids by the catalytic activity of horseradish peroxidase (HRP) in the presence of excess H2O2 was investigated. Four monocarboxylic acids, nine dicarboxylic acids, and two tricarboxylic acids, all of which are non- or weakly fluorescent, were effectively converted into fluorescent compounds using this new method. This technique was further ...

Mn(II) salen complex immobilized on nano silicagel was prepared by incorporating Mn(II) salen complex into a nanosilica matrix and characterized by TGA, XRD, atomic absorption spectroscopy and was successfully applied as catalyst for the oxidation of alcohols. Oxidation of a series of alcohols in acetonitrile over immobilized Mn(II) salen complex using tetrabutylammonium peroxymonosulfate (TBAO...

The use of an inorganic phase in water-in-oil (w/o) microemulsion has recently received considerable attention for preparing metal oxide nanoparticles. This is a technique, which allows preparation of ultrafine metal oxide nanoparticles within the size range 40 to 80 nm. Preparation of nano chromium (III) oxide studied investigated in the inverse microemulsion system. Therefore the nucleation o...

1. In a previous study the administration of benzoate, a-naphthoate, diethylstilbestrol disulfate and various aromatic carboxylic acids to adrenalectomized rats was shown to increase hepatic tyrosine transaminase (L-tyrosine:2-oxoglutarate aminotransferase, EC 2.6.1.5) levels several fold. The action of benzoate was strongly inhibited by the concurrent administration of puromycin or actinomycin...

The carbonaceous chondrite meteorites are fragments of asteroids that have remained relatively unprocessed since the formation of the solar system 4.6 billion years ago. These carbon-rich objects contain a variety of extraterrestrial organic molecules that constitute a record of chemical evolution prior to the origin of life. Compound classes include aliphatic hydrocarbons, aromatic hydrocarbon...