Blue light emitting diodes enhance the antivirulence effects of Curcumin against .

Growing concern about the increasing frequency of resistance of to the available antimicrobial agents worldwide has encouraged the search for new strategies in treating and eradicating infections. Endoscopic blue-light therapy has been used in patients with gastritis with limited success due to subsequent repopulation with . Clinical trials using Curcumin could not eradicate infection either. We studied the effect of blue light emitting diodes (LEDs) in conjunction with Curcumin on , since this has not been previously reported. We examined the effect of Curcumin with and without irradiation with blue LEDs on the viability of and four key factors important for colonization and establishment of infection, namely urease production, motility, adhesion and biofilm formation. We found that a combination of Curcumin and blue LEDs caused significant reductions in viability, urease production, motility, haemagglutination activity, as well as increased disruption of mature preformed biofilms of , in comparison to Curcumin alone (<0.0001), at sublethal concentrations of Curcumin. Targeting the virulence factors of with blue LED photoactivated Curcumin would theoretically cripple this pathogen from colonizing and causing tissue damage and perhaps overcome the problem of repopulation with that often occurs following endoscopic blue-light therapy.