Abstract
Candida species are considered commensal micro-organisms as they can be found to occur naturally in humans. However, under certain circumstances Candida species can become pathogenic and result in the development of a fungal infection known as candidiasis. For many years, antifungal medications have been regarded as a primary means of treatment for candidiasis, however, overuse of this class of drugs has led to increasing rates of antifungal treatment resistance. The Echinacea species, specifically Echinacea angustifolia (E. angustifolia) (DC.) Hell. and Echinacea purpurea (E. purpurea) (L.) Moench, are commonly used medicinal plants which have been shown to exhibit antifungal properties when used individually, however, their combined properties as a mother tincture preparation on Candida species are unknown.
The aim of this quantitative in vitro study is to determine the antifungal properties of a combination of E. purpurea and E. angustifolia as a mother tincture preparation on clinically relevant Candida strains in vitro. This study was conducted at the Water and Health Research Centre (WHRC) at the University of Johannesburg, Doornfontein campus, under the supervision of qualified laboratory technicians with relevant permission obtained. The antimicrobial activity of the E. angustifolia and E. purpurea mother tincture combination was tested by means of exposing clinically isolated Candida strains, obtained from Lancet Laboratories, to varying concentrations of the compounds. This was done using the microdilution method in 96 well plates to determine the Minimum Inhibitory Concentration (MIC) of the compounds. Controls included fluconazole, the yeast control, the solvent control (ethanol of 64%) and the media control. The tests were conducted in triplicate and repeated on three different days to test the repeatability and reproducibility of the experiments.
The results of this study showed that the E. purpurea and E. angustifolia mother tincture combination produced a clear growth inhibition effect on the yeast strains. The tinctures showed an inhibitory effect on all the various Candida strains, with the exception of the repeat test on one strain (C. auris) that did not show growth inhibition after 24 hours. C. auris was however inhibited by the ethanol control. Furthermore, the results showed that the growth inhibition effect decreased after 48 hours.
E. pupurea and E. angustifolia homoeopathic mother tincture combination did yield a noteworthy degree of inhibition of fungal growth against a good percentage of the Candida strains utilized in this study. This study contributes to the body of antimicrobial research involving E. pupurea and E. angustifolia homoeopathic mother tinctures.