Antifungal Activity of Black Tea Polyphenols (Catechins and Theaflavins) against <i>Candida </i>Species

Abstract

Background/Aims: The polyphenols catechins and theaflavins in black tea have been shown to possess many medicinal properties, including anticancer activity and some antifungal characteristics, but there have been few studies of their anti-Candida activity. In this paper we report the results of our study of the anti-Candida activity of tea polyphenols. Methods: The effects of 4 different concentrations of catechins and theaflavins were evaluated on 5 isolates each of 5 Candida species employing an agar diffusion growth inhibition assay. The minimum inhibitory concentration (MIC) of the polyphenols against C. albicans was determined. The post-antifungal effect (PAFE) of the polyphenols for C. albicans was investigated. C. albicans cells exposed to polyphenols were studied using a scanning electron microscope (SEM). Results: Both polyphenols showed anti-Candida activity against all tested Candida species and demonstrated a MIC of 6.25 mg/ml for C. albicans. C. glabrata was found to be the most sensitive species followed by C. parapsilosis, C. albicans, C. krusei and C. tropicalis (p < 0.05 for all). Significant intraspecies variations in sensitivity were noted among C. parapsilosis and C. tropicalis (p < 0.001) for both polyphenols. Theaflavins displayed standard PAFE while catechins showed a paradoxical PAFE with all isolates of C. albicans. SEM revealed considerable cell wall damage of C. albicans cells exposed to the polyphenols. Conclusion: The study reveals for the first time the anti-Candida properties of black tea polyphenols that may find therapeutic applications in future.

Antioxidant and antifungal activities of Camellia sinensis (L.) Kuntze leaves obtained by different forms of production

“…(Martinez and Garcia-Casanovas., 2006). Black tea polyphenols (catechins and theaflavins) present activity on Candida species (Sitheeque et al, 2009), but when Almajano et al, (2008) comparatively analyzed infusion teas, the anticandidal activity was higher in non-fermented teas. However, their study was performed in a different strain of Candida, C. albicans ATCC 1002, under extractive conditions with a different methodology than the present study.…”

In vitro antifungal activity against Candida species of Sri Lankan orthodox black tea (Camellia sinensis L.) belonging to different agro-climatic elevations

“…The polyphenols, catechins and theaflavins isolated from Sri Lankan black tea, although the grades are not specified, are shown to have antifungal activities against 5 Candida species: C. albicans, Candida glabrata, Candida parapsilosis, Candida krusei, and Candida tropicalis [8]. We have previously shown that the three grades of tea used in this study contained substantial amounts of catechin and theaflavins [11,12].…”

“…and OP) belonging to the three agro-climatic elevations (low, mid and high) of the country [4]. The in vitro technique used to ascertain the antifungal activity was a widely employed inexpensive and well-established method [7,8]. Methanolic extracts were employed since they were the most common solvent used in investigation of plant products for anti-fungal activity [9,10].…”

“…Satheeque et al [8] have shown that catechins and theaflavins extracted from Sri Lankan black tea (grade or agro-climatic elevations were not specified) have anti-fungal activity against C. tropicalis.…”

Black and white teas as potential agents to combine with amphotericin B and protect red blood cells from amphotericin B-mediated toxicity

“…Previous work has demonstrated the antifungal activity of white and black teas, which is due to the differential preparation of the terminal leaves and apical buds of the plant Camellia sinensis (L.) (Almajano et al, 2008;Friedman, 2007;Sitheeque et al, 2009). One study demonstrated that the antifungal activity of these teas and their individual component, theaflavin digallate inhibited the growth of Trichophyton mentagrophytes and Trichophyton rubrum (Okubo et al, 1991).…”