Inhibitory Effect of Standardized Extract and Fractions of Nigella sativa L. on Nystatin Susceptible and Clinically Nystatin Resistant Candida albicans.

INTRODUCTION: Candidiasis infection is caused by different species of Candida, which are characterized by host immunologic weakness. Black cumin seeds (Nigella sativa) have shown an inhibitory effect against Candida albicans. In this work, the inhibitory effect of standardized extract and different fractions of Nigella sativa seeds has been evaluated on both nystatin-susceptible and resistant strain of C. albicans. MATERIALS AND METHODS: Canadida albicans (NSCA) with ATCC 76645 and nystatin-resistant Candida albicans (NRCA) were prepared from oral samples of HIV individuals. Total extract and different fractions of N. sativa were prepared using maceration and sonication methods. Thymoquinone (TQ) content of the plant was determined by spectrophotometric method. Total extract (TTE) and the fractions along with TQ were evaluated on NSCA and NRCA by the microdilution method. RESULTS: TQ content of the plant was 0.92 ± 0.37g/100g dried extract. The least MIC and MFC (62.5 and 125 µg/ml, respectively) were due to petroleum ether fraction (PEF) against both NSCA and NRCA, followed by chloroform fraction (CHF) with MIC and MFC of 125 and 250 µg/ml, respectively. TQ exhibited MIC of 0.78 and 3.12 µg/ml against NSCA and NRCA, stronger than nystatin (MIC of 2 and 16 µg/ml, respectively). Thymoquinone was detected in the PEF and CHF. CONCLUSION: Considering more inhibitory effects of PEF and CHF than TTE, we can conclude that active components of the plant belong to non-polar compounds. PEF showed identical inhibitory effects on NRCA and NSCA, which is a valuable result for finding novel medicaments against NRCA infections.

Trachyspermum ammi aromatic water: A traditional drink with considerable anti-Candida activity.

BACKGROUND AND PURPOSE: Aromatic waters (AWs) are therapeutic distillates, which harbor both essential oil and water-soluble components of a plant. Due to the dispersion of the light amount of essence through the AWs, they have their specific pleasant smell, taste, and medicinal properties. In Iranian traditional medicine, Trachyspermum ammi AW is used to treat gastrointestinal disorders. The present study was conducted to determine the chemical composition of the essential oil extracted from T. ammi AW and its antifungal activities against Candida species. MATERIALS AND METHODS: The composition of the essential oil extracted from T. ammi AW was analyzed by gas chromatography-mass spectrometry. In addition, the evaluation of the antifungal activity of AW against Candida species was performed using broth microdilution methods as recommended by the Clinical Laboratory Standard Institute. Moreover, the biofilm formation inhibition, antioxidant properties, and experimental activity of AW were determined in an animal model. RESULTS: According to the results, thymol (78.08%) was the major compound of EO, followed by carvacrol (8.20%) and carvotanacetone (6.50%). Furthermore, T. ammi AW exhibited antifungal activities against the examined fungi and inhibited the biofilm formation of C. albicans at a concentration of up to 0.25 V/V. Histopathological analyses revealed that Candida colonization declined in the mice following the administration ofT. ammi AW in a therapeutic trial. CONCLUSION: It seems that the presence of phenolic monoterpenes in AW has resulted in antifungal effects. Pleasant odor and antioxidant properties are extra bonuses to the antimicrobial effects of this plant. Based on the findings, AW might have the potential to be used in the management of alimentary candidiasis or oral hygienic products.

In vitro and in vivo antidermatophytic activities of some Iranian medicinal plants.

In the last decades, the number of people suffering from dermatophytoses has seriously increased, which may be due to the development of resistant strains to a range of antifungal drugs. The present study was aimed to evaluate the antidermatophytic properties of eight extracts from the selected spices and herbs, which were ethno-medicinally used in Iran against Trichophyton mentagrophytes, Trichophyton interdigitale, Microsporum canis, and Microsporum gypseum (10 strain of each). The in vitro antifungal activities of the extracts from four spices and four plants were evaluated by the broth macro dilution method against four dermatophyte strains. In addition, the in vivo therapeutic effects of Myrtus communis L. and Cinnamomum zeylanicum Blume extracts (the most active extracts) on dermatophytosis induced by M. canis and T. mentagrophytes in guinea pigs were evaluated. Results of in vitro antifungal assay revealed that all the tested extracts demonstrated both fungistatic and fungicidal activities with the geometric mean (GM) MIC ranging from 0.058 to 3.73 mg/ml and GM (MFC) ranging from 0.058 to 7.46 mg/ml, respectively. Two extracts (M. communis and C. zeylanicum) significantly inhibited the growth of all the tested dermatophytes, while other extracts demonstrated weak (MICs of >0.625 mg/ml) to moderate (MICs ranging from 100 to 0.625 mg/ml) activities. In vivo antidermatophytic assay demonstrated that clotrimazole cured T. mentagrophytes and M. canis infection on days 21 and 17, respectively, whereas M. communis and C. zeylanicum extracts significantly (p < 0.05) cured T. mentagrophytes and M. canis infection on days 9 and 13 as well as 9, 11, respectively. Phytochemical screening showed the presence of flavonoids, tannins, phenols, and alkaloids in M. communis and alkaloids, flavonoids, and tannins in C. zeylanicum. Findings of the present study also provided the scientific evidence that natural plants could be used in traditional medicine for the prevention and treatment of dermatophytic infections.