1. Comparison of Chemical Composition and Antibacterial Activity of Nigella sativa Seed Essential Oils Obtained by Different Extraction Method. .
- Author
-
Kokoska, L., Havlik, J., Valterova, I., Sovova, H., Sajfrtova, M., and Jankovska, I.
- Subjects
BLACK cumin ,ESSENTIAL oils ,ANTIBACTERIAL agents ,DISTILLATION ,GAS chromatography ,GRAM-positive bacteria ,GRAM-negative bacteria - Abstract
Nigella sativa L. seed essential oils obtained by hydrodistillation (HD), dry steam distillation (SD), steam distillation of crude oils obtained by solvent extraction (SE-SD), and supercritical fluid extraction (SFE-SD) were tested for their antibacterial activities, using the broth microdilution method and subsequently analyzed by gas chromatography and gas chromatography-mass spectrometry. The results showed that the essential oils tested differed markedly in their chemical compositions and antimicrobial activities. The oils obtained by HD and SD were dominated by p-cymene, whereas the major constituent identified in both volatile fractions obtained by SD of extracted oils was thymoquinone (ranging between 0.36 and 0.38 g/ml, whereas in oils obtained by HD and SD, it constituted only 0.03 and 0.05 g/ml, respectively). Both oils distilled directly from seeds showed lower antimicrobial activity (MICs ≥ 256 and 32 µg/ml for HD and SD, respectively) than those obtained by SE-SD and SFE-SD (MICs ≥ 4 µ/ml). All oil samples were significantly more active against gram-positive than against gram-negative bacteria. Thymoquinone exhibited potent growth-inhibiting activity against gram-positive bacteria, with MICs ranging from 8 to 64 µg/ml. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF