Inhibition of urease activity in the urinary tract pathogens Staphylococcus saprophyticus and Proteus mirabilis by Uva Ursi

Abstract

This study was designed to compare the sensitivities of ureases from Staphylococcus saprophyticus and Proteus mirabilis to different over-the-counter preparations of Uva Ursi (Arctostaphylos uva-ursi) and to determine if they can inhibit the increase in pH that occurs in cultures as a result of urease activity. The Nature’s Answer® Uva Ursi preparation was the more effective inhibitor in cell-free extracts. Neither enzyme was inhibited by arbutin, but the enzymes were partially inhibited by hydroquinone and 1,4-benzoquinone. The Nature’s Answer® Uva Ursi preparation and 1,4-benzoquinone could partially inhibit urease in whole cells of S. saprophyticus and P. mirabilis. Exposure of S. saprophyticus cultures in artificial urine medium to Nature’s Answer® Uva Ursi slowed the increase in pH. Uva Ursi preparations should be used with caution for the treatment of urinary tract infections since they vary in concentration and bacterial pathogens with urease activity differ in their sensitivity to them.