The effect of some unsubstituted aromatic amines and their oand p-hydroxylated derivatives on isolated rat-liver mito chondria has been studied. The o-hydroxylated amines inhibited oxygen uptake in the presence of nicotinamide adenine dinucleotide-dependent respiratory substrates. Of the other compounds only l-amino-4-naphthol inhibited oxygen uptake. The Buccinate oxidase system was inhibited ...

Microbial desulfurization, or biodesulfurization (BDS), of fuels is a promising technology because it can desulfurize compounds that are recalcitrant to the current standard technology in the oil industry. One of the obstacles to the commercialization of BDS is the reduction in biocatalyst activity concomitant with the accumulation of the end product, 2-hydroxybiphenyl (HBP), during the process...

We investigated the biodesulfurization potential of a mixed culture AK6 enriched from petroleum hydrocarbons-polluted soil with dibenzothiophene (DBT) as a sulfur source. In addition to DBT, AK6 utilized the following compounds as sulfur sources: 4-methyldibenzothiophene (4-MDBT), benzothiophene (BT), and 4,6- dimethyldibenzothiophene (4,6-DM-DBT). None of these compounds supported the growth o...

Biphenyl metabolism in Aspergillus toxicarius occurs by successive hydroxylations in the 4- and 4'-positions, followed by conjugation with sulfate to produce 4-hydroxybiphenyl-O-sulfonic acid and 4,4'-dihydroxybiphenyl-O-sulfonic acid. The hydroxylation reactions normally occur only after a prolonged lag period after which the appearance of the monohydroxylated compound precedes the dihydroxyla...

Biodesulfurization was monitored in a recombinant Pseudomonas putida CECT5279 strain. DszB desulfinase activity reached a sharp maximum at the early exponential phase, but it rapidly decreased at later growth phases. A model two-step resting-cell process combining sequentially P. putida cells from the late and early exponential growth phases was designed to significantly increase biodesulfuriza...

Benzene, diphenyl sulfone (DPS), para-hydroxybiphenyl (PPP), ortho-hydroxybiphenyl (OPP), higher hydroxybiphenyls, and alkylated benzenes were found in a small lake receiving contaminated groundwater discharge from the Industri-Plex Superfund site (Woburn, MA) in the Aberjona watershed in eastern Massachusetts. All of these chemicals may derive from the former phenol manufacturing activities pr...

Biotransformation in carcinogen-induced diploid and polyploid hepatocytes was studied using isozyme-selective substrates for several enzyme pathways. Diploid hepatocytes were induced by partial hepatectomy, a single injection of diethylnitrosamine, and 4 weeks of 2-acetylaminofluorene (2-AAF) feeding. Then, after an additional 3-5 weeks on the control diet, diploid and polyploid hepatocytes wer...