Intestinal microsomal biphenyl

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) ... 

Benzo(a)pyrene hydroxylase activities in hepatic and intestinal microsomes of fiber-fed rats are presented in Table VIII. There were no significant differences (0.05 level) among any of the purified fiber treatment groups in either liver or intestinal microsomes. Lab Chow-fed rats had the lowest liver microsomal benzo(a)pyrene hydroxylase (AHH) level. The indication of enhanced intestinal P-448-dependent hydroxylation of biphenyl in the pectin-fed rats (seen as elevated 3-hydroxybiphenyl formation in microsomes, Table Vl) was not supported by these preliminary data. 

Table VI. Biphenyl Hydroxylase Activity in Intestinal Microsomes of Fiber-Fed Rats. ...

Fiber Type Intestine x) Length (cm) Mucosal x) Weight (g) Microsomal x) Protein (mg/g) 2-OH Biphenyl Hydroxylase 3-OH 4- -OH... 

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