Titanium dioxide effect on bacteriolytic activity and intrinsic fluorescence of lysozyme

The effect of the white pigment titanium dioxide (TiO2) on the protein enzyme, the bacteriolytic component of the innate immune system, lysozyme, was evaluated. The effects of TiO2 in the form of nanoparticles, microparticles and particles used in the food industry at concentrations of 0.001-0.0001 mg/ml, corresponding to the calculated average daily intake and 10-fold dilution, were studied. It was found that a lower concentration of TiO2 (0.0001 mg/ml) of all particles types acts more efficiently, significantly reducing after 30 minutes, and completely blocking the own fluorescence of recombinant lysozyme after 60 minutes. TiO2 particles of three types at a higher concentration (0.001 mg/ml) completely block the intrinsic fluorescence of recombinant lysozyme after 60 minutes. After 30 minutes only microparticles cause a decrease in the intrinsic protein fluorescence. The inhibition of the bacteriolytic activity of recombinant lysozyme against the culture of K. pneumoniae under the action of nanoparticles, microparticles and particles of food TiO2 at concentrations of 0.001-0.0001 mg/ml was revealed.