The spermicidal compound nonoxynol-9 increases adhesion of Candida species to human epithelial cells in vitro

All 25 strains of Candida spp. tested were able to grow in medium supplemented with 25% nonoxynol-9 in vitro. Adhesion of Candida spp. to HeLa cells was found to increase in the presence of 5% nonoxynol-9 (2.2- to 6.6-fold; P less than 0.001) and, to a lesser extent, in 12.5% nonoxynol-9. Adhesion of Candida strains cultured in medium supplemented with nonoxynol-9 varied, with five of six strains of Candida albicans and the single strain of Candida tropicalis demonstrating increases of 1.4 to 4.0 times control levels (P less than 0.05). The increased adhesion did not correlate with altered yeast cell surface hydrophobicity or germ tube formation.