Monitoring of Candida biofilm inhibition by Galenia africana using real-time impedance-based technology.

Background and purpose: Yeasts of the Candida genus are responsible for localized and disseminated infections, especially in immunocompromised populations. These infections are exacerbated by the rapid increase in drug-resistant strains, which limits treatment options and increases patient morbidity and mortality. Therefore, the utilization of easily accessible natural products as alternatives to conventional medicines has gained interest. South Africa is home to a rich biodiverse natural flora of which many are known for their antimicrobial activity, including the antifungal effects of their plant extracts. Galenia africana (kraalbos) is a local indigenous plant found to have various traditional uses, including the treatment and prevention of various human infections.

Materials and methods: In this study, the activity of G. africana against Candida albicans and Candida glabrata preformed biofilm formation and its antibiofilm activity were tested using the xCELLigence system, which monitors biofilm formation in real time using impedance.

Results: Presence of G. africana resulted in a dose-dependent decrease in Candida biofilms and was found to be effective in the prevention of Candida biofilm formation and disruption of the existing Candida biofilms.

Conclusion: The xCELLigence impedance-based system proved to be an effective tool for medication screening. To the best of our knowledge, this is the first reported study to use real-time monitoring of a medicinal plant on microbial biofilm formation.