Green synthesis of silver nanoparticles using Zingiber officinale and Thymus vulgaris extracts: characterisation, cell cytotoxicity, and its antifungal activity against Candida albicans in comparison to fluconazole.

Fluconazole (FLZ) application as a highly successful commercial antifungal azole agent to treat the fungal infections is limited due to emergence of FLZ-resistant candida. In this study, the potential of green synthesised silver nanoparticles (NPs) as an antifungal agent against Candida albicans fungal pathogen is investigated. The extract of ginger (Zingiber officinale) and thyme (Thymus vulgaris) plays as reducing agent, capping agent and antifungal agent. The UV-visible spectroscopy shows the peak of surface plasmon resonance of synthesised Ag NPs after a period of time. The synthesised Ag NPs are spherical, with average sizes of 12 and 18 nm based on ginger and thyme extract, respectively. Fourier transform infrared spectroscopy confirms the adsorption of the plant extract on the surface of the as-prepared Ag NPs. Based on the minimum inhibitory concentration (MIC) method against Candida albicans, the antifungal activity of as-prepared green synthesised Ag NPs shows higher inhibitory in comparison to FLZ. Finally, the Ag NPs synthesised via thyme extract shows no cytotoxicity with concentration below 3.5 ppm, which can be considered as an appropriate candidate instead of FLZ to treat the superficial fungal infections.

The effect of betamethasone and IFN-gamma on replication of Toxoplasma gondii (RH strain) and nitric oxide production in Hela cell culture.

Toxoplasmosis is a protozoal infection caused by Toxoplasma gondii. Toxoplasmosis produce severe damage in patients who are immunosuppressed. In those who are immunosuppressed, latent infection can be reactivated resulting in acute disseminating disease. Betamethasone is a synthetic glycocorticoid, used as an anti-inflammatory and immunosuppressant in a wide variety of disorders. The aim of this study was evaluation of betamethasone as an immunosuppressor drug on infected cells by Toxoplasma gondii. In this study, at first HeLa cells were grown in 24 well culture plates in culture medium . When confluent monolayer was obtained, we compared 6 groups to evaluate the effect of betamethasone as a corticosteroid drug (two concentrations 4 and 40 micro g/ml) and the effect of IFN-gamma (100 IU/ml ) on growth, replication and Nitric Oxide (NO) production. The results showed, that high number of plaques were seen in group with 40 mug/ml of betamethasone and the lowest number of plaques were seen in group with 100 IU of IFN-gamma. The difference between plaque number in control and groups treated with IFN-gamma and betamethasone was significant (P<0.05). The groups with betamethasone or IFN-gamma without tachyzoites did not show any effect on cell structures. Replication rates in the wells treated with IFN-gamma were decreased significantly 72 h post inoculation in comparison with control group (P<0.05). There was no significant difference among different groups in NO production. The results indicated that betamethasone increase the invasion of tachyzoites to host cells in vitro.