Research Product

An indirect atomic-absorption spectrophotometric (IAAS) method has been applied to the selective determination of aliphatic and phenolic 1,2-diols. Microsomal epoxide hydrolase (E.C. 3.3.2.3.) plays an important role with the cytochrome P450-mediated mixed function oxidase (MFO) system in the metabolism of polyaromatic hydrocarbons and xenobiotics. Specifically, epoxide hydrolase catalyzes the hydrolysis of an epoxide to a 1,2-diol. When styrene epoxide is used as a substrate, styrene glycol can be determined in the presence of unreacted styrene epoxide. Hepatic microsomes from New Zealand white rabbits and freshwater fish, Tilapia aurea, were used. Control animals were compared with those treated with Aroclor 1254 (A) and trans-stilbene oxide (TSO). When a dose of 490 mg kg-1 of TSO was injected into the animals, the epoxide hydrolase activity was induced by 350% and 210% for the rabbit and tilapia, respectively. Inhibition of the enzyme actively was also carried out with the specific epoxide hydrolase inhibitor trichloropropane oxide (TCPO).