Green Tea and Struvite Crystals in Relation to Infectious Urinary Stones: The Role of (−)-Epicatechin

Abstract

The influence of (−)-epicatechin, a component of green tea, on the nucleation and growth of struvite crystals, the main component of infectious urinary stones, is studied. The struvite crystallization process was performed in the solution of artificial urine, and the activity of urease−bacterial enzyme was simulated in a chemical way. The effect of the tested substance on the crystallization processes was monitored by spectrophotometric measurements and microscopic observations. The results obtained show that, in the presence of (−)-epicatechin, struvite nucleation occurs faster when compared with the control test. This means that its nucleation is shifted toward lower pH values. It has been also found that the presence of the tested substance can lead to an increase in the mass of struvite formed in artificial urine. The experimental results are explained on the basis of theoretical chemical speciation analysis of chemical complexes formed in artificial urine. This chemical speciation analysis demonstrat...