Biphenyl hydroxylation

Table VI. Bromobenzene and Biphenyl Hydroxylation via the Hepatic MFO System in Normal and Ascorbic Acid Deficient Guinea Pigs...

Billings RE, McMahon RE. 1978. Microsomal biphenyl hydroxylation the formation of... 

Gardner AM, Chen JT, Roach JAG, et al. 1973. Polychlorinated biphenyls Hydroxylated urinary metabolites of 2,5,2, 5 -tetrachlorobiphenyl identified in rabbits. Biochem Biophys Res Commun 55 1377-1384. 

Intestinal microsomal metabolism can be monitored via biphenyl hydroxylation as well. Biphenyl hydroxylase assays are more sensitive than some other hydroxylase assays which has permitted measurements of the low constituative enzyme levels in intestinal mucosa and some other extrahepatic tissues (56-59) ... 

Arylhydrocarbon Hydroxylase. Benzo(a)pyrene (BaP) is considered an ideal model compound for monitoring arylhydrocarbon hydroxylase (AAH) MFO levels in rats. Its metabolism has been widely investigated in both rat liver and extrahepatic tissues (40-41,61 -70). Arylhydrocarbon hydroxylase has been compared to biphenyl hydroxylase in the intestines of rats (25,28). Intestinal AAH has been shown to be induced up to 30-fold with cytochrome P-448-type inducers, while being insensitive to P-450-type induction. Therefore, we have used intestinal AAH in conjunction with biphenyl hydroxylation, to evaluate the effects of dietary fibers on intestinal metabolism. 

Arcaro KF, Vakharia DD, Yang Y, et al. 1998. Lack of synergy by mixtures of weakly estrogenic hydroxylated polychlorinated biphenyls and pesticides. Environ Health Perspect 106(Suppl. 4) 1041-1046. 

For polychlorinated biphenyls (PCBs), rate constants were highly dependent on the number of chlorine atoms, and calculated atmospheric lifetimes varied from 2 d for 3-chlorobiphenyl to 34 d for 236-25 pentachlorobiphenyl (Anderson and Hites 1996). It was estimated that loss by hydroxy-lation in the atmosphere was a primary process for the removal of PCBs from the environment. It was later shown that the products were chlorinated benzoic acids produced by initial reaction with a hydroxyl radical at the 1-position followed by transannular dioxygenation at the 2- and 5-positions followed by ring fission (Brubaker and Hites 1998). Reactions of hydroxyl radicals with polychlorinated dibenzo[l,4]dioxins and dibenzofurans also play an important role for their removal from the atmosphere (Brubaker and Hites 1997). The gas phase and the particulate phase are in equilibrium, and the results show that gas-phase reactions with hydroxyl radicals are important for the... 

Considerable attention has been directed to the formation of nitroarenes that may be formed by several mechanisms (a) initial reaction with hydroxyl radicals followed by reactions with nitrate radicals or NO2 and (b) direct reaction with nitrate radicals. The first is important for arenes in the troposphere, whereas the second is a thermal reaction that occurs during combustion of arenes. The kinetics of formation of nitroarenes by gas-phase reaction with N2O5 has been examined for naphthalene (Pitts et al. 1985a) and methylnaphthalenes (Zielinska et al. 1989) biphenyl (Atkinson et al. 1987b,c) acephenanthrylene (Zielinska et al. 1988) and for adsorbed pyrene (Pitts et al. 1985b). Both... 

Seigle-Murandi FM, SMA Krivobok, RL Steiman, J-LA Benoit-Guyod, G-A Thiault (1991) Biphenyl oxide hydroxylation by Cunninghamella echinulata. J Agric Food Chem 39 428-430. 

Buckman AH, CS Wong, EA Chow, SB Brown, KR Solomon, AT Fisk (2006) Biotransformation of polychlorinated biphenyls (PCBs) and bioformation of hydroxylated PCBs in fish. Aquat Toxicol 78 176-185. 

Golbeck JH, SA Albaugh, R Radmer (1983) Metabolism of biphenyl by Aspergillus toxicarius induction of hydroxylating activity and accumulation of water-soluble conjugates. J Bacteriol 156 49-57. 

Smith RV, PJ Davis, AM Clark, S Glover-Milton (1980) Hydroxylations of biphenyl by fungi. J Appl Bacterial 49 65-73. 

Smith RV, PJ Davis, AM Vlark, SK Prasatik (1981) Mechanism of hydroxylation of biphenyl by Cunningha-mella echinulata. Biochem J 196 369-371. 

Wiegel J, X Zhang, Q Wu (1999) Anaerobic dehalogenation of hydroxylated polychlorinated biphenyls by Desulfitobacterium dehalogenans. Appl Environ Microbiol 65 2217-2221. 

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