American Journal of Infectious Diseases and Microbiology
ISSN (Print): 2328-4056 ISSN (Online): 2328-4064 Website: Editor-in-chief: Maysaa El Sayed Zaki
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American Journal of Infectious Diseases and Microbiology. 2014, 2(5), 122-130
DOI: 10.12691/ajidm-2-5-5
Open AccessArticle

N-acetylcysteine Inhibits and Eradicates Candida albicans Biofilms

El-Baky Rehab Mahmoud Abd1, , Dalia Mohamed Mohamed Abo El Ela1 and Gamal Fadl Mamoud Gad1

1Department of Microbiology, Faculty of Pharmacy, Minia University, Minia, Egypt

Pub. Date: November 04, 2014

Cite this paper:
El-Baky Rehab Mahmoud Abd, Dalia Mohamed Mohamed Abo El Ela and Gamal Fadl Mamoud Gad. N-acetylcysteine Inhibits and Eradicates Candida albicans Biofilms. American Journal of Infectious Diseases and Microbiology. 2014; 2(5):122-130. doi: 10.12691/ajidm-2-5-5


N-acetylcysteine (NAC) is used in the treatment of chronic bronchitis that attributed to its mucus dissolving properties. Its ability to reduce biofilm formed by different types of bacteria was proven previously in many studies. Therefore we examined its effect on C. albicans biofilms by testing its effect alone and in combination with ketoconazole using Tissue culture plate assay method (TCP). NAC effects on C. albicans morphology and the texture of biofilms were determined using Scanning electron microscope (SEM). It was found that the inhibitory effect of NAC was concentration dependent. NAC reduced C. albicans adherence by ≥32.8% while ketoconazole reduced adherence by ≥25% in comparison to control. Also, it showed higher disruptive effect (50-95%) than ketoconazole (22-80.7%) on mature biofilms. Using NAC and ketoconazole in combination, a significant inhibitory effect (P<0.01) on both adherence and mature biofilms (54-100%) was seen. NAC reduced the amount of biofilm mass in all tested Candida in concentrations at which their growth was not affected. NAC and ketoconazole combinations showed complete eradication to mature biofilms formed in most of the tested strains. NAC can inhibit C. albicans growth, inhibit dimorphism, which is an important step in biofilm formation, and change the texture of the formed biofilms, what makes NAC an interesting agent to be used as an inhibitor for biofilm formation by C. albicans.

antifungal mature biofilm mucolytics adherence SEM

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