IADR Abstract Archives
Antibacterial Effects of Black Cumin Seed Components on Fusobacterium Biofilm
Objectives: Methyl mercaptan (CH3SH) produced by oral bacteria is a principal contributor to oral malodor. Black cumin seed (Nigella sativa L., BCS) essential oil has antibacterial activity and deodorizing effects on CH3SH. The main component of BCS is thymoquinone (TQ), but the effects of specific BCS components on biofilm bacteria that produce oral malodor are unclear. In this study, we examined the antibacterial effects of BCS components on a single species biofilm of Fusobacterium nucleatum (Fn).
Methods: A solution of Fn was diluted 32 times and cultivated in a in 96-well microtiter plate in tryptic soy broth (TSB) or TSB containing membrane vesicles from Streptococcus mutans GS-5. After cultivation, planktonic bacteria were removed and the formed biofilms were washed with phosphate buffered saline (PBS). The biofilms were then incubated with 0.01, 0.025, or 0.05% TQ or an antibacterial agent [thymol, cetylpyridinium chloride (CPC), or isopropyl methyl phenol (IPMP)] in model mouthwash at room temperature for 3 min. Then, the films were washed with PBS, stained with a live/dead cell staining kit, and observed by confocal laser scanning microscope. The Fn biofilms were quantified by optical density readings at 492 nm after staining with Gram-Hucker solution.
Results: TQ, thymol, CPC, and IPMP increased the ratio of dead cells to live cells more than model mouthwash with no antibacterial agent. Except for TQ, this occurred in a dose-dependent manner. A low concentration of TQ, which is a commercially acceptable mouth-wash level, had antibacterial effects against Fn biofilm formation. There were no differences between the level of Fn biofilm formation with TQ and other antibacterial agents at the 0.01% level.
Conclusions: The BCS component TQ has antibacterial effects on malodorous microbes such as Fn in biofilms, and a deodorizing effect on CH3SH. BCS is a useful material for prevention of oral malodor.
Methods: A solution of Fn was diluted 32 times and cultivated in a in 96-well microtiter plate in tryptic soy broth (TSB) or TSB containing membrane vesicles from Streptococcus mutans GS-5. After cultivation, planktonic bacteria were removed and the formed biofilms were washed with phosphate buffered saline (PBS). The biofilms were then incubated with 0.01, 0.025, or 0.05% TQ or an antibacterial agent [thymol, cetylpyridinium chloride (CPC), or isopropyl methyl phenol (IPMP)] in model mouthwash at room temperature for 3 min. Then, the films were washed with PBS, stained with a live/dead cell staining kit, and observed by confocal laser scanning microscope. The Fn biofilms were quantified by optical density readings at 492 nm after staining with Gram-Hucker solution.
Results: TQ, thymol, CPC, and IPMP increased the ratio of dead cells to live cells more than model mouthwash with no antibacterial agent. Except for TQ, this occurred in a dose-dependent manner. A low concentration of TQ, which is a commercially acceptable mouth-wash level, had antibacterial effects against Fn biofilm formation. There were no differences between the level of Fn biofilm formation with TQ and other antibacterial agents at the 0.01% level.
Conclusions: The BCS component TQ has antibacterial effects on malodorous microbes such as Fn in biofilms, and a deodorizing effect on CH3SH. BCS is a useful material for prevention of oral malodor.