In the past two decades, few reports have confirmed the various antibacterial activities of total extract from the seeds of Nigella sativa (Black cumin). In attempts to identify the active ingredients in this extract, the seeds were extracted with hexane. The volatile oil obtained from the crude extract was shown to contain at least three distinct compounds, thymoquinone, p-cymene, and α-pinene, as confirmed by GC/MS and NMR spectroscopy. While p-cymene and α-pinene showed no antibacterial activities, thymoquinone, exhibited remarkable inhibition of the growth of various strains of bacteria. For instance, the IC50 and the Minimal Inhibitory Concentration (MIC) for thymoquinone were found to be 1.31 μg/mL and 3.6 μg/mL respectively, when tested against the gram-positive bacteria, S. aureus. It is also found that thymoquinone significantly inhibites the protein and RNA synthesis in S. aureus.
","abstract_html":"<p>In the past two decades, few reports have confirmed the various antibacterial activities of total extract from the seeds of <em>Nigella sativa</em> (Black cumin). In attempts to identify the active ingredients in this extract, the seeds were extracted with hexane. The volatile oil obtained from the crude extract was shown to contain at least three distinct compounds, <em>thymoquinone</em>, <em>p-cymene</em>, and <em>α-pinene</em>, as confirmed by GC/MS and NMR spectroscopy. While <em>p-cymene</em> and α-pinene showed no antibacterial activities, <em>thymoquinone</em>, exhibited remarkable inhibition of the growth of various strains of bacteria. For instance, the IC<sub>50</sub> and the Minimal Inhibitory Concentration (MIC) for <em>thymoquinone</em> were found to be 1.31 μg/mL and 3.6 μg/mL respectively, when tested against the gram-positive bacteria, <em>S. aureus</em>. It is also found that <em>thymoquinone</em> significantly inhibites the protein and RNA synthesis in <em>S. aureus</em>.</p>","abstract_has_math":false,"creators":["Kahsai, Alem Welderufael"],"institution":null,"degree_name":"MS (Master of Science)","degree_level":"Thesis - restricted","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2002,"date_issued":"2002-08-16T07:00:00Z","date_published":"2002-08-16T07:00:00Z","updated_at":"2026-07-24T02:19:21Z","subjects":["Nigella sativa","Black seed","Thymoquinone","antibacterial","Chemistry","Physical Sciences and Mathematics"],"languages":[],"rights":["Copyright by the authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://dc.etsu.edu/etd/692","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Kahsai, Alem Welderufael"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2002-08-16T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - restricted"]},{"key":"thesis:degree_name","label":"Degree Name","values":["MS (Master of Science)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Nigella sativa","Black seed","Thymoquinone","antibacterial","Chemistry","Physical Sciences and Mathematics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Copyright by the authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://dc.etsu.edu/context/etd/article/1849/viewcontent/KashaiA072502.pdf","https://dc.etsu.edu/etd/692"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["In the past two decades, few reports have confirmed the various antibacterial activities of total extract from the seeds of Nigella sativa (Black cumin). In attempts to identify the active ingredients in this extract, the seeds were extracted with hexane. The volatile oil obtained from the crude extract was shown to contain at least three distinct compounds, thymoquinone, p-cymene, and α-pinene, as confirmed by GC/MS and NMR spectroscopy. While p-cymene and α-pinene showed no antibacterial activities, thymoquinone, exhibited remarkable inhibition of the growth of various strains of bacteria. For instance, the IC50 and the Minimal Inhibitory Concentration (MIC) for thymoquinone were found to be 1.31 μg/mL and 3.6 μg/mL respectively, when tested against the gram-positive bacteria, S. aureus. It is also found that thymoquinone significantly inhibites the protein and RNA synthesis in S. aureus.
"]},{"key":"dc:title","label":"Title","values":["Isolation and Characterization of Active Ingredients from Nigella Sativa for Antibacterial Screening."]}]}],"canonical_facts":{"dc:creator":["Kahsai, Alem Welderufael"],"dc:date.issued":["2002-08-16T07:00:00Z"],"dc:description.abstract":["In the past two decades, few reports have confirmed the various antibacterial activities of total extract from the seeds of Nigella sativa (Black cumin). In attempts to identify the active ingredients in this extract, the seeds were extracted with hexane. The volatile oil obtained from the crude extract was shown to contain at least three distinct compounds, thymoquinone, p-cymene, and α-pinene, as confirmed by GC/MS and NMR spectroscopy. While p-cymene and α-pinene showed no antibacterial activities, thymoquinone, exhibited remarkable inhibition of the growth of various strains of bacteria. For instance, the IC50 and the Minimal Inhibitory Concentration (MIC) for thymoquinone were found to be 1.31 μg/mL and 3.6 μg/mL respectively, when tested against the gram-positive bacteria, S. aureus. It is also found that thymoquinone significantly inhibites the protein and RNA synthesis in S. aureus.
"],"dc:identifier":["https://dc.etsu.edu/context/etd/article/1849/viewcontent/KashaiA072502.pdf","https://dc.etsu.edu/etd/692"],"dc:rights":["Copyright by the authors."],"dc:subject":["Nigella sativa","Black seed","Thymoquinone","antibacterial","Chemistry","Physical Sciences and Mathematics"],"dc:title":["Isolation and Characterization of Active Ingredients from Nigella Sativa for Antibacterial Screening."],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["Thesis - restricted"],"thesis:degree_name":["MS (Master of Science)"]},"updated_at":"2026-07-24T02:19:21Z"}