Suppression of Urinary Odor Generation by <i>β</i>-Glucuronidase Inhibitors

Abstract

Phenols are a group of odorous components that are released from rotten human urine. Just after urination, the most abundant urinary phenols exist in odorless conjugates with glucuronic acid or sulfate. In this study, we analyzed these two types of conjugates in rotten human urine using LC-MS/MS and found that only the glucuronic acid conjugates (glucuronides) underwent degradation. This suggested that suppression of glucuronide degradation would effectively reduce urinary odor generation. Thus, about 200 fragrance chemicals were examined in an attempt to find an inhibitor of the bacterial enzyme involved in glucuronide degradation ( β-glucuronidase). Macrocyclic compounds, such as 8-cyclohexadecen-1-one, exhibited strong inhibitory activity against β-glucuronidase and were effective at reducing urinary odor generation.