Аннотация:Lysozyme is an enzyme with bacteriolytic activity. Lysozyme is also involved in the regulation of the immune response, as an opsonin and a necessary factor in the functioning of antigen-presenting phagocytic immune cells. Thus, substances which harm the bacteriolytic activity of lysozyme are also potentially able to affect the functionality of the immune system.Sodium lauryl sulfate (also called dodecyl sulfate, SDS) is a surfactant, often applied as a basic component of cosmetic remedies, particularly shampoos and toothpastes. In the following research we have discovered inhibition of lysozyme activity by sodium lauryl sulfate in concentrations two to three orders of magnitudelower than the permissible concentrations of this substance in cosmetics (35 mM in toothpastes, 870 mM in shampoos).As a result of the research, the concentrations of sodium lauryl sulfate were determined at which the activity of lysozyme decreases by 50% (IC50). При pH 7.0 (the pH value characteristic for human oral cavity) the value of IC50 equals 0.26 ± 0.03mM, at pH 8.5 (human scalp pH value) it equals 0.29 ± 0.04mM. There is evidence in the literature about skin diseases caused by the action of sodium laurylsulfate. Our research demonstrates that at least one of the factors of the negative impact caused by this surfactant is inhibition of lysozyme. The data obtained show the necessity of revising the standards for the content of sodium lauryl sulfate in cosmetics.
