Effect of sodium sulfate on the hydrolysis of 17-hydroxycorticosteroid- and p-nitrophenyl-glucuronides with beta-glucuronidase preparations from bovine liver.

Previous papers dealt with the discovery that hydrolysis of 17-hydroxycorticosteroid glucuronides in urine with beta-glucuronidase preparations from bovine liver is increased by adding sodium sulfate to the incubation medium. Here, we conclude that sodium sulfate not only increases the activity of bovine liver beta-glucuronidase on 17-hydroxycorticosteroid glucuronides and p-nitrophenyl glucuronides, but also removes the inhibitory activity of substances of high molecular weight in urine and, moreover, inhibits urine putrefaction during the hydrolysis. The net effect is an increased yield of urinary 17-hydroxycorticosteroids. In the incubation with sodium sulfate (Na2SO4, final concentration 80 g/liter, 500 Fishman units of beta-glucuronidase per milliliter of urine, pH 5.0, 48 degrees C, 18 h) the analytical recovery of 17-hydroxycorticosteroid glucuronides added to 12 urine samples proved to be 98 +/- 1.8% (95-100).