Characterizing four Iranian monofloral honeys and their in vitro effects onCandida albicans growth and biofilm formation

The purpose of this study is to investigate the effect of pure honey of thyme, Citrus aurantium, jujube,and barberry on the inhibition of biofilm formation by the resistant strain of Candida albicans. In thisstudy, two yeast strains, O۳۱ and G۱۰۹, were isolated from patients undergoing endoscopy. As weknow, Candida albicans yeast contamination is one of the challenges in medical science today, especiallyregarding the contamination of medical devices through their biofilm formation. On the other hand, theresistance of these yeasts to various drugs and antifungal substances is increasing, which has forcedresearchers to look for alternative treatment methods to treat and remove this microorganism andprevent biofilm formation by it. In this area, the use of honey has opened new doors for researchers touse these natural compounds to inhibit the growth and formation of biofilm by yeasts. The effect ofthyme Citrus aurantium, jujube, and barberry honey on these yeasts was investigated in this studythrough different methods. These methods include well-diffusion, microplate method and biofilm assay.Materials and methods: After separating pure and single flower honeys and their detailed andcomprehensive analysis, each of these honeys in the microbiology laboratory of Shahid BeheshtiUniversity in different concentrations of ۱۰۰, ۹۵, ۹۰, ۸۵, ۸۰, And ۷۵% were prepared. To controlwhether these honeys are contaminated or not, they were placed in the incubator at ۳۷ degrees Celsiusfor ۲۴ hours. After making sure that the honeys are not contaminated, the well-diffusion method wasperformed on the BHI agar medium. After that, microplates containing different concentrations of eachhoney, two yeast suspensions, and liquid BHI medium were placed in the incubator, the contents ofeach well were spread on the BHI agar plate. Finally, the formation or non-formation of biofilm by twoyeast strains was investigated by biofilm assay method. Results: Although no inhibition zone wasobserved during the well-diffusion, but with the increase in honey concentration, the growth rate ofyeasts decreased significantly. The same result was also observed in the microplate method. As a resultof the biofilm evaluation method, no biofilm was formed in the presence of all concentrations of honeyfor one of the strains while for the other, the concentrations above ۸۰ percent inhibited the formationof biofilm. Discussion: The obtained results indicate that the growth of yeasts decreases significantlywith the increase in the concentration of honey used, especially Citrus aurantium honey. Thenoteworthy point in this topic is the absence of biofilm formation in the presence of honey, which canbe a solution to the challenges in the field of contamination of medical devices

کلیدواژه ها:

Candida albicans ، honey ، biofilm ، barberry ، jujube ، Citrus aurantium ، thyme.