Antimicrobial activity of traditional and newly synthetized surface-active agents as a basis for the creation of new disinfectants

Abstract

Aim. The main goal of the study was to investigate the antibacterial and fungicidal properties of the traditional and newly synthesized surfactants of different classes, compare the analysis of their antimicrobial activity and find out the prospects for further use for the creation of disinfectants. Methods. The biocidal activity of the studied cationic, anionic and nonionic surfactants was determined in relation to representatives of the species Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, as well as fungi Candida albicans. The detection of antibacterial and fungicidal effect and determination of minimum inhibitory concentrations (MIC) was carried out by cultivation of the test cultures of microorganisms in Nutrient Broth (NB, Himedia, India) for 24–48 hours at 37 °С in the presence of different concentrations of experimental surfactants (1000–0.1 ppm). The number of cells that remained viable after exposure to surfactants was determined by optical density in McFarland units, which were then converted to the number of cells in 1 ml using the standard McFarland scale. Results. The newly synthesized guanidine-containing oligomer at concentrations of 1000 and 100 ppm inhibited the growth of all test cultures without exception by 100 %. The biocidal effect on the representatives of various taxonomic groups of microorganisms differed in its effectiveness for various anionic surfactants (trilon B, surfactant 2 and surfactant 3) even at the highest concentration of 1000 ppm. In particular, only trilon B completely inhibited the growth of all test cultures. However, at the concentrations indicated above, the examined cationic (surfactant 1 and triethanolamine) and nonionic (OP-10 and triton X-100) exhibited a rather low antimicrobial activity. Conclusions. The results obtained indicate that the guanidine-containing oligomer exhibited the highest antimicrobial activity among the investigated surfactants. Therefore, it can be considered a promising surfactant for further use in the creation of broad-spectrum antimicrobial agents. Enhancement of the biocidal effect of newly created disinfectants can be implemented by introducing the studied anionic and nonionic detergents, and glutaraldehyde can be used to stabilize them or enhance their antimicrobial activity. Instead, the application of cationic surfactants used in the work is impractical.