Research Article

Effect of Tyrosol and Farnesol on Virulence and Antibiotic Resistance of Clinical Isolates of Pseudomonas aeruginosa

Table 1

Effect of farnesol and tyrosol on hemolysin production in Egyptian isolates of P. aeruginosa.

Isolate numberControlTyrosol effectFarnesol effect
Hemolysis percent caused by the isolateBefore normalizationAfter normalizationBefore normalizationAfter normalization


The values in the control column represent the levels of hemolysin production by the isolates (SD = 30.6), indicated by hemolysis percent, without addition of farnesol and tyrosol. The values in the columns of tyrosol and farnesol stand for either nonnormalized values (SD = 10.2 and 13.5 for tyrosol and farnesol, resp.) or normalized values. The latter values indicate the percent of either decrease (negative values) or increase (positive values) in the production of hemolysin after normalization to untreated samples (control). All values represent the mean of three independent experiments.