Investigation of the effect of curcumin and nystatin, independently and in combination, on Candida albicans biofilm formation in laboratory settings

Objective: Biofilm formation is an important factor in the pathogenesis of Candida albicans , which leads to persistent infection and antibiotic resistance in humans. We investigated the in vitro activities of antibiotic nystatin and curcumin, either alone or in combination against biofilms of Candida albicans . Methods The Mycology Laboratory at Golestan University of Medical Sciences in Grogan, Iran gathered 399 clinical isolates of Candida albicans, with 168 (42%) from urinary tract infections (UTI) and 231 (58%) from vulvovaginal candidiasis (VVC). To determine antifungal susceptibility and biofilm formation, the microdilution broth and tetrazolium salt (XTT) reduction assays were conducted. Results In a concentration-dependent pattern, nystatin and curcumin significantly reduced biofilm formation in all strains. Curcumin was observed to have a detachment effect on biofilms at concentrations of 8 µg/ml, 16 µg/ml, and 32 µg/ml. The sub-MIC, MIC, and 2MIC values of nystatin ranged from 6 to 12 µg/mL, 8 to 16 µg/mL, and 32 to 64 µg/mL, respectively. When combined with curcumin, the inhibition of biofilm formation by antifungals was significantly reduced by 4- to 32-fold. Conclusions The combination of nystatin and curcumin exhibited impressive effectiveness in countering biofilms, including their prevention and combat in Candida albicans .