Abstract
D-Glucaric acid, a β-glucuronidase inhibitor, in various mammalian urine was determined by using both chemical and enzymic methods. The different results obtained from two methods and the high recovery of added D-glucaric acid Obtained from enzymic method suggested the presence of a strong inhibitor of β-glucuronidase other than D-glucaric acid in guinea-pig urine. It was a non-dialyzable inhibitor of β-glucuronidase. Sodium chloride was added to guinea-pig urine dialyzed to 0.58M to precipitate Tamm-Horsfall mucoprotein. After centrifugation at 7970×g, a non-dialyzable β-glucuronidase inhibitor was isolated and extensively purified from the spernatant by Sephadex G-50 chromatography, by treatment with pronase-P, trypsin, and papain in order to remove the contamination of denatured proteins, and by preparative paper electrophoresis. The purified inhibitor of β-glucuronidase was judged homogeneous by polyacrylamide gel electrophoresis and Sephadex G-100 chromatography.
