[Efficiency of ethanol of Thonningia sanguinea against Cryptococcus neoformans]

Herbal treatment of infectious diseases is a common practice in traditional society. One of the herbs used by African populations against skin and systemic infectious diseases is Thonningia sanguinea (THOS). In the Ivory Coast, Togo, and Ghana, this herb is used to prepare traditional remedies for diarrhoeas, asthma and mycoses. The latter account for a substantial number of the opportunistic infections associated with HIV/AIDS. Some species of eumycetes, such as Cryptococcus neoformans, infect mainly immunocompromised patients but can sometimes infect immunocompetent hosts and they are often fatal. In this study we evaluated the antimicrobial activity of aqueous extracts of T. sanguinea against C. neoformans (and several other microorganisms). We first assessed the fungal growth in vitro on agar medium. We then incubated the cultures for 48 h with various concentrations of THOS to determine the percentage of survival according to the concentration of THOS and the concentration required for 50% inhibition (IC50). The minimum fungicidal concentration (MFC) of the total aqueous extract was 6.25 mg/mL. (THOS was thus most effective against C. neoformans). Accordingly we sought to improve the extract by preparing it with ethanol. This solution yielded an IC50=0.06 mg/mL and an MFC=0.098 mg/mL against C. neoformans.