Enzymatic profile, adhesive and invasive properties of Candida albicans under the influence of selected plant essential oils.

Abstract

The influence of essential oils (EOs) used at sublethal level, on the presence and intensity of Candida albicans virulence factors was evaluated. Minimal inhibitory concentrations (MICs) of Lemon balm, Citronella, Geranium and Clove oils were established as 0.097% (v/v). Using the agar plates with substrates for proteases, phospholipases and hemolysins it was shown that C. albicans ATCC 10231 and C. albicans ATCC 90028 strains differed in the type and amount of enzymes produced. No significant difference in their total amount could be detected after pretreatment for 24 h with EOs at ½ MIC. However, the short-term (1 h) acting oils at MIC caused a statistically significant reduction in this activity. In the API ZYM test it was demonstrated that both strains exhibited activity of the same 9 out of 19 enzyme types and that EOs caused a significant decrease in the release of some of them. In the presence of subMIC of EOs, or when the fungus had previously been exposed to the MIC of oil, germ tubes formation was significantly and irreversibly reduced. Such C. albicans spotted on the Spider agar containing EOs at subMICs were unable to penetrate the agar. A significant decrease in the C. albicans adhesion to the fibroblast monolayer with respect to controls was also demonstrated when yeasts had been exposed to EOs at MIC (1 h) in liquid medium. Thus, it has been shown that tested oils, used even at subMIC, exhibit significant activity reducing the presence/quantity of important C. albicans virulence factors.

Interactions between Terpinen-4-ol and Nystatin on biofilm of Candida albicans and Candida tropicalis

“…A statistically significant decrease in the adherence of Candida albicans (ATCC 10231) to fibroblasts compared to controls was demonstrated in a study where the organisms were exposed to MIC of essential oils (lemon balm, citronella, geranium clove). However, when the same test was carried out in the presence of half of the CIM, as in this study, their adhesion ability was not significantly affected, which corroborates our results (24). According to Sun et al (11), the resistance of Candida albicans biofilms to the penetration of liquid antimicrobials, including terpinen-4ol, is limited due to its low wettability.…”

Efficacy of citronella and cinnamon essential oils on Candida albicans biofilms

“…Previous studies have indeed demonstrated the antimicrobial activity of essential oils from cinnamon and citronella [20,22,30,31]. However, the MIC and MFC values encountered in the present study were lower than those reported by others.…”

Antimicrobial and Cytotoxic Properties of Bisquaternary Ammonium Bromides of Different Spacer Length

“…The surfactants 8–6–8, 8–7–8, 8–8–8, 8–9–8 were tested against the selected microbes for their inhibitory activity using a modified broth microdilution method, as described previously (Budzyńska et al, ; Budzyńska, Sadowska, Więckowska‐Szakiel, & Różalska, ; Yin et al, ). Briefly, serial twofold dilutions of surfactants (concentrations at range: 5.47–10.18 μmol·cm −3 ) were prepared in TSB or RPMI‐1640 media and deposited at volume 100 μL in triplicate in the 96‐well flat‐bottom polystyrene microplates (Nunc, Denmark).…”