Zearalenone (ZEA) and its derivatives are mycotoxins with estrogenic effects on mammals. The biotransformation for ZEA in animals involves the formation of two major metabolites, α- and β-zearalenol (α-ZOL and β-ZOL), which are subsequently conjugated with glucuronic acid. The capability of Saccharomyces cerevisiae strains isolated from silage to eliminate ZEA and its derivatives α-ZOL and β-ZO...

Enzyme catalyzed biotransformation of the energetic chemical octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is not known. The present study describes a xanthine oxidase (XO) catalyzed biotransformation of HMX to provide insight into the biodegradation pathway of this energetic chemical. The rates of biotransformation under aerobic and anaerobic conditions were 1.6+/-0.2 and 10.5+/-0.9 n...

A chimeric oxygenase, in which the P450cam domain was fused to the reductase host domains of a P450RhF from Rhodococcus sp. strain NCIMB 9784 was optimised to allow for a biotransformation at 30 mM substrate in 80% overall yield, with the linker region between P450 and FMN domain proving to be important for the effective biotransformation of (+)-camphor to 5-exo-hydroxycamphor.

A detailed study of the biotransformation of 6- and 7-methoxyflavones by four fungal strains (Aspergillus niger strains MB, KB, and SBP; Penicillium chermesinum 113) was carried out. Products of demethylation and also demethylation combined with hydroxylation at C-4' were identified. The biotransformation products were stronger antioxidants than the substrates.

The preparation of some ring A and B epoxy steroids derived from testosterone, pregnenolone and epiandrosterone using m-chloroperbenzoic acid is described. The biotransformation of the epoxy products by the fungus Mucor plumbeus are performed. The introduction of the epoxy group into the steroids moiety has affected the biotransformation results and gave only hydrolyzed products.

The hereditary liver disease, acute intermittent porphyria (ALP), 1 is characterized clinically by a disabling, sometimes lethal, neurological-visceral symptom complex and biochemically by excessive activity of the porphyrin-heme biosynthetic pathway (1-3). The mitochondrial enzyme 6-aminolevulinate synthetase (ALAS), which is rate limiting for this pathway (4), is found at high levels of activ...

Selenium (Se) is an element that has been of environmental concern in aquatic systems that drain arid regions heavily used for agricultural purposes. As hypersaline conditions are associated with these ecosystems, this study examined the effect of hypersaline water on the uptake, biotransformation, and toxicity of seleno-L-methionine (SeMe) in juvenile rainbow trout. Fish were acclimated for 5 ...

This study set out to clarify whether the inhibition of sterol or nonsterol derivatives arising from mevalonate biotransformation plays a major role in the in vivo anti-inflammatory action of statins. Hepatic synthesis of all these derivatives was inhibited in mice by administered statins, whereas squalestatin inhibited only sterol derivatives. Using a short-term treatment schedule, we found th...

Benzbromarone (BBR) is effective in the treatment of gout; however, clinical findings have shown it can also cause fatal hepatic failure. Our early studies demonstrated that CYP3A catalyzed the biotransformation of BBR to epoxide intermediate(s) that reacted with sulfur nucleophiles of protein to form protein covalent binding both in vitro and in vivo. The present study attempted to define the ...

Hepatic cytosolic alcohol and aldehyde dehydrogenases (ADHs and ALDHs) catalyze the biotransformation of xenobiotics (e.g., cyclophosphamide and ethanol) and vitamin A. Because age-dependent hepatic abundance of these proteins is unknown, we quantified protein expression of ADHs and ALDH1A1 in a large cohort of pediatric and adult human livers by liquid chromatography coupled with tandem mass s...