Combined Effect of Optical Radiation of the Blue and Red Spectra and Antiseptic Drugs on the Ability to Form Biofilm of Proteus mirabilis Isolates

The relevance of this topic is related to the need of developing rational antimicrobial therapy, the use of which will provide an opportunity to prevent the emergence of resistant to antimicrobial drugs of microorganisms. Despite the progress in the development and improvement of existing methods of antimicrobial therapy of purulent inflammatory processes, this problem remains a priority in modern medicine and microbiology. It happens due to the extremely high growth of antibiotic resistant strains of microorganisms, which is associated with the ability of bacteria to form a protective biofilm around them. Thus, the purpose of this study was to check the complex action of antiseptic drugs that are widely used in practical medicine, and the optical radiation of blue and red spectra on the ability to form biofilm by Proteus mirabilis isolates. Materials and methods. The object of the study was antiseptic drugs (chlorhexidine and hydrogen peroxide) and Proteus mirabilis, isolated from patients with purulent-inflammatory processes. Enzymatic identification of microorganisms was carried out using identification kits. The synchronization of periodic culture was carried out after establishing the kinetics growth of asynchronous culture. Measurement of the optical density of microorganisms' biofilm was carried out after one-hour incubation by comparing the optical density of the experimental and control biofilm formed. It helped to determine the degree of biofilm formation. The quantitative expression of the degree of biofilm formation and the ability to aggregate the planktonic cells is the value of the optical density on the Multiskan EX 355 spectrophotometer at 540 nm. The result was determined in conventional units of optical density of biofilm formation by microorganisms. The exposure to in vitro was carried out by LED sources of blue (440-480 nm) and red (620-740 nm) radiation of the photon matrix of the Korobov apparatus "Barva-Flex", which contains an LED matrix with super-fluorescent light-emitting diodes and a power supply. We used the program Exel and Biostat for the statistical processing of the results. Results and discussion. The analysis of the results showed that in the application of optical radiation of the red spectrum, along with the antimicrobial drug chlorhexidine, the suppression of the formation of Proteus mirabilis planktonic cells was 3.2 fold compared with the control objects without irradiation and 5 times the antiseptic preparation of hydrogen peroxide. In the complex application of the LED radiation of the blue spectrum and chlorhexidine, suppression of the suspension culture of Proteus mirabilis was detected in 5.9 times, while in the case of hydrogen peroxide application it was 5.6 times compared with the control objects without irradiation. Analyzing the results of the ability of the biofilm formation with planktonic cells after the complex action of optical radiation of blue and red spectra and antimicrobial agents on suspensions of isolates of proteins, Proteus mirabilis we found out that under the influence of light emitting diodes of the blue spectrum the sensitivity of the isolates to chlorhexidine significantly increases, which prevents the formation of dense bioplates by isolates: the ability to form biofilm is reduced in 10,4 times in comparison with the control values without any influence of optical radiation and in the complex application with an antiseptic preparation of hydrogen peroxide - inhibition of the formation of biofilm – 9.2 times. With the definite ability of day biofilm Proteus mirabilis, which were formed after applying antiseptic drugs and LED radiation on bacterial cultures of isolates, to form planktonic cells, it was established that under the influence of LED radiation of the red spectrum there is a suppression of the formation of planktonic cells in the complex with chlorhexidine – 29.3 times, in combination with hydrogen peroxide.