In this study, in vitro antidermatophytic activity against Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis, and Microsporum gypseum was studied by disk diffusion test and assessment of minimum inhibitory concentration (MIC) using CLSI broth macrodilution method (M38-A2). Moreover, antileishmanial and cytotoxicity activity of B. vulgaris and berberine against promastigotes of Leishmania major and Leishmania tropica were evaluated by colorimetric MTT assay. The findings indicated that the various extracts of B. vulgaris particularly berberine showed high potential antidermatophytic against pathogenic dermatophytes tested with MIC values varying from 0.125 to >4 mg/mL. The results revealed that B. vulgaris extracts as well as berberine were effective in inhibiting L. major and L. tropica promastigotes growth in a dose-dependent manner with IC₅₀ (50% inhibitory concentration) values varying from 2.1 to 26.6 μg/mL. Moreover, it could be observed that berberine as compared with B. vulgaris exhibited more cytotoxicity against murine macrophages with CC₅₀ (cytotoxicity concentration for 50% of cells) values varying from 27.3 to 362.6 μg/mL. Results of this investigation were the first step in the search for new antidermatophytic and antileishmanial drugs. However, further works are required to evaluate exact effect of these extracts in animal models as well as volunteer human subjects.

Leishmaniasis is a complex disease with a broad spectrum of clinical presentations. We evaluated the anti-leishmanial effects of Nigella sativa L. (Ranunculaceae) against Leishmania tropica and Leishmania infantum with an in vitro model. Antileishmanial effects of essential oil and methanolic extract of N. sativa (0-200 µg/mL) and thymoquinone (0-25 µg/mL) on promastigotes of both species and their cytotoxicity activities against murine macrophages were evaluated using the MTT assay at 24, 48, and 72 h. Moreover, their leishmanicidal effects against amastigotes were investigated in a macrophage model, for 48 and 72 h. The findings showed that essential oil (L. tropica IC50 9.3 μg/mL and L. infantum IC50 11.7 μg/mL) and methanolic extract (L. tropica IC50 14.8 μg/mL and L. infantum IC50 15.7 μg/mL) of N. sativa, particularly thymoquinone (L. tropica IC50 1.16 μg/mL and L. infantum IC50 1.47 μg/mL), had potent antileishmanial activity on promastigotes of both species after 72 h. In addition, essential oil (L. tropica IC50 21.4 μg/mL and L. infantum IC50 26.3 μg/mL), methanolic extract (L. tropica IC50 30.8 μg/mL and L. infantum IC50 34.6 μg/mL), and thymoquinone (L. tropica IC50 2.1 μg/mL and L. infantum IC50 2.6 μg/mL) mediated a significant decrease in the growth rate of amastigote forms of both species. Thymoquinone (CC50 38.8 μg/mL) exhibited higher cytotoxic effects against murine macrophages than the other extracts. N. sativa, especially its active principle, thymoquinone, showed a potent leishmanicidal activity against L. tropica and L.infantum with an in vitro model.

Mahmoudvand H, et al. Korean J Parasitol. 2014 Dec;52(6):653-659. http://dx.doi.org/10.3347/kjp.2014.52.6.653