IADR Abstract Archives
Effect of Black Cumin Seed Oil on Methionine Gamma-lyase from Fusobacterium Nucleatum
Objectives: Methionine gamma-lyase in which oral bacteria catalyzes methionine to produce methyl mercaptan (CH3SH) that is a principal contributor to oral malodor. We have reported that the essential oil extracted from Black cumin (Nigella sativa L.) seed (BC oil) has deodorizing effects on CH3SH at IADR 2016. In this study, we examined the effect of BC oil on the methionine gamma-lyase inhibition to clarify the mechanism of deodorizing effects on CH3SH comparing BC oil ingredients (thymoquinone, thymol) and antibacterial agents (4-isopropyl-3-methylphenol, cetylpyridinium chloride).
Methods: The recombinant methionine gamma-lyase was purified from Escherichia coli that was transformed with FN1419 gene that encodes methionine gamma-lyase in Fusobacterium nucleatum ATCC25586. The recombinant protein was incubated with or without BC oil in the presence of 10 mM methionine and 0.01 mM pyridoxal 5'-phosphate for 30 min at 37 degrees Celsius. The enzymatic activity was determined by measurement of keto acid production from the methionine using the 2,4-dinitrophenylhydrazine method.
Results:
The methionine gamma-lyase activity was strongly inhibited by 0.001% BC oil as same level as 1 mM thymoquinone or 1 mM cetylpyridinium chloride. On the other hand, thymol and 4-isopropyl-3-methylphenol couldn’t inhibit methionine gamma-lyase at the same concentration.
Conclusions: BC oil and it’s ingredient thymoquinone may be a useful material for prevention of oral malodor by inhibiting methionine gamma-lyase.
Methods: The recombinant methionine gamma-lyase was purified from Escherichia coli that was transformed with FN1419 gene that encodes methionine gamma-lyase in Fusobacterium nucleatum ATCC25586. The recombinant protein was incubated with or without BC oil in the presence of 10 mM methionine and 0.01 mM pyridoxal 5'-phosphate for 30 min at 37 degrees Celsius. The enzymatic activity was determined by measurement of keto acid production from the methionine using the 2,4-dinitrophenylhydrazine method.
Results:
The methionine gamma-lyase activity was strongly inhibited by 0.001% BC oil as same level as 1 mM thymoquinone or 1 mM cetylpyridinium chloride. On the other hand, thymol and 4-isopropyl-3-methylphenol couldn’t inhibit methionine gamma-lyase at the same concentration.
Conclusions: BC oil and it’s ingredient thymoquinone may be a useful material for prevention of oral malodor by inhibiting methionine gamma-lyase.