[ODP-222] Inhibitory effect of thymoquinone on biofilm formation of Fusobacterium nucleatum
Fusobacterium nucleatum (FN) deeply integrates into subgingival plaque formation by intercalating the early and late bacterial colonizers on tooth surfaces. In addition, inflammatory responses to FN are associated with the progression of periodontitis. Nigella sativa Lin. seed, which is known as black cumin (BC), has been used as a herbal medicine to treat ailments such as asthma and infectious diseases. This study examined the inhibitory effect of BC oil and its active components, thymol (TM) and thymoquinone (TQ), on biofilm formation and inflammation induced by FN. FN containing biofilms were prepared by co cultivation with an early dental colonizer, Actinomyces naeslundii (AN). The stability and biomass of FN/AN dual species biofilms were significantly higher than those with FN alone. This effect was observed even with prefixed cells, indicating that FN/AN co aggregation is mediated by physicochemical interactions of cell surface molecules. FN/AN biofilm formation was significantly inhibited by 0.1% TM or TQ. TQ dose dependently suppressed TNF α production from a human monocytic cell line, THP 1, which was exposed to FN, yet showed no toxicity to the cell. These results indicate that oral hygiene care using TQ is expected to reduce FN associated biofilm and inflammation in subgingival tissue.