The Antifungal and Antibiofilm Activities of Caffeine against Candida albicans on Polymethyl Methacrylate Denture Base Material

Abstract

Background: In this study, the effect of pure caffeine was established against Candida albicans (C. albicans) using different microbiological techniques. Methods: Broth microdilution and colony forming units (CFUs) assays were used to detect the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). The Live/Dead fluorescent dyes were implemented to determine the yeast viability. Polymethyl methacrylate acrylic resin (PMMA) discs were prepared to evaluate caffeine’s effects against adherent C. albicans using microplate reader, CFUs, and scanning electron microscope (SEM). Results: caffeine’s MIC was detected around 30 mg/mL, while the MFC was considered at 60 mg/mL. In an agar-well diffusion test, the inhibition zones were wider in caffeine groups. The Live/Dead viability test verified caffeine’s antifungal effects. The optical density of the adherent C. albicans on PMMA discs were lower at 620 nm or 410 nm in caffeine groups. CFU count was also reduced by caffeine treatments. SEM revealed the lower adherent C. albicans count in caffeine groups. The effect of caffeine was dose-dependent at which the 60 mg/mL dose demonstrated the most prominent effect. Conclusion: The study reinforced caffeine’s antifungal and antibiofilm properties and suggested it as an additive, or even an alternative, disinfectant solution for fungal biofilms on denture surfaces.

Azorean Black Tea (Camellia sinensis) Antidermatophytic and Fungicidal Properties

“…Theaflavins are known to be present in black teas, since it results from the fermentation process that leads to the oxidation of the catechins to theaflavins [27], which present antifungal activity [30]. Caffein was also identified in the ABT extract, which was expected because black tea is known to contain this compound [52], and also presents antifungal activity [40]. Theaflavins, catechins and caffein were also reported in Azorean Black Tea from other producers (the Gorreana Tea Factory), and their proportions vary depending on the plant part used and on the fermentation time and temperature [49].…”

“…Several polyphenolic compounds, such as the catechins galloyl-(epi)gallocatechin-(epi)gallocatechin, (epi)gallocatechin, (epi)gallocatechin gallate and the theaflavin gallate, as well as methylxanthine caffein, have been identified in the ABT extract, and since catechins and caffein are described for their antifungal activity [30,40], the antidermatophytic activity of the ABT extract was evaluated.…”

In Vitro Evaluation of Candida albicans Adhesion and Related Surface Properties of CAD/CAM Denture Base Resins

“…The biofilm assay by determination of CFU is a common microbiological research technique; however, this process is laborious, tedious, and time-consuming. 23 Future research should focus on studying the biofilm of C. albicans using other methods such as Cell Proliferation Assay Kits. This study is limited as the effect of aging or denture cleaning routines on the tested properties was not tested.…”

“…To remove nonadherent cells, the specimens were washed three times with phosphate buffer saline (PBS), then scraped and vortex for 2 minutes at 3,000 rpm to dislodge the adherent cells from the specimens. 22 23 24 To enumerate CFU count, 10-fold dilution in PBS was performed, before a volume of 100 µL was directly platted onto SDA plates and incubated at 30°C for 48 hours. The experiment was performed blindly in triplicates with positive and negative controls to ensure reproducibility.…”

The Inhibitory Effect of Sodium Bicarbonate, Phylex and Seaweed Extract Against Penicillium digitatum Causing Green Rot Disease in Local Lemon Fruits

“…A significant effect was observed when Sodium bicarbonate or Sodium carbonate used to control the growth of P.digitatum in orange fruits after harvesting. Recent studies, also indicated that using of Sodium bicarbonate and Sodium carbonate salts protected the fruits from P. digitatum and P. italicum infections and possible re-infection during storage [67,68].…”