Antibacterial effect of brilliant blue food dye

Brilliant blue is largely found in ice cream, canned processed peas, packet soups, blue raspberry flavored products, dairy products, sweets and drinks. It is also used in soaps, shampoos, mouthwash and other hygiene and cosmetics applications (Archived from Florida). This study was aimed to investigate the antimicrobial effects of Brilliant blue on Bacillus subtilis as a gram positive bacterial strain and Pseudomonas aeruginosa as a gram negative bacterial strain with MIC, MBC, and disk diffusion assay. MIC values of Brilliant blue against Bacillus subtilis was 5µg/ml, and MBC values was 60 µg/ml and MIC values of Brilliant blue against Pseudomonas aeruginosa are 10 µg/ml, and MBC values was 80 µg/ mL. In this study Brilliant blue had only a bacteriostatic effect on two bacterial strains. The result of disk diffusion assay showed that Brilliant blue (0.625, 1.25, and 1.875 µg) has not antimicrobial activity against Bacillus subtilis and Pseudomonas aeruginosa. It can be concluded that Brilliant blue might not pose a potential risk for our bacterial flora. However, it must be evaluated with different new studies.