Epoxide hydrolase activities in Drosophila melanogaster

Epoxide hydrolase (EH) activity in Drosophila melanogaster cell fractions was characterized using juvenile hormone (JH III) and $\text{cis-}\text{stilbene}$ oxide (CSO) as substrates. A comparison of detergents indicated that 0.3% Lubrol PX was relatively effective for solubilizing EH activity from the 20,000 and 100,000 g pellets. The effect of inhibitors, pH, temperature, salt and organic solvents on EH activity depended on the substrate and cell fraction tested, which suggested there were multiple activities present. For initial purification, polyethylene glycol was useful for precipitating EH activity from the 100,000 g supernatant.