Title : Microbiological activity of bovhyaluronidaze azoximer against microbial biofilms
Abstract:
Background. Biofilm-related infections are most often characterized by low susceptibility to treatment due to the difficulty of antibiotics penetration into the biofilm. This fact repeatedly increases the level of antimicrobial resistance (AMR). In turn, the spread of AMR significantly reduces the effectiveness of available therapy regimens.
Currently there are several notable strategies of microbial biofilm reduction, including enzymatic hydrolysis of the biofilm matrix. The latter has low toxicity and doesn’t characterised by the risk of resistance development, facilitating the antibiotics cell penetration.
Aims. To evaluate the ability of bovhyaluronidaze azoximer to destroy biofilms formed by clinical strains of microorganisms.
Methods. The study included 50 clinical strains of Staphylococcus aureus (25 strains), Staphylococcus epidermidis (6), Enterococcus faecalis (8), Escherichia coli (9), Candida albicans (2), isolated from hospitalized and outpatient patients. Antimicrobial susceptibility testing was performed using broth microdilution method. Biofilm formation culturing with antibiotics, bovhyaluronidaze azoximer and their combinations was assessed in Mueller-Hinton broth and brain heart broth in 96-well plates. Biofilms are fixed with 2,5% glutaraldehyde solution, stained with 0,25% crystal violet solution, which is extracted by 33% acetic acid solution.
Results. All methicillin-resistant strains of S. aureus were able to form biofilms. The optical density values for them were (Me; LQ-UQ) 0,212; 0,079-0,336.
A significant dose-dependent enzymatic destruction of the biofilm matrix of S. aureus as well as C. albicans was noted when applying a concentration of 1000 IU/ml of bovhyaluronidaze azoximer. The most prominent enzymatic destruction of the biofilm matrix of E. coli occurred in concentration of 1000 IU/ml, but also manifested in 250 IU/ml and 64 IU/ml. For all S. epidermidis strains the biofilm matrix was destroyed when treated with bovhyaluronidaze azoximer at a concentration of 250 IU/ml or 1000 IU/ml. The E. faecalis biofilms were found to be safe to the enzyme exposure.
Conclusions. Bovhyaluronidaze azoximer can destroy the matrix of preformed biofilms of methicillin-resistant strains of S. aureus as well as S. epidermidis, E. coli, C. albicans in concentrations of 64-1000 IU/ml, while exerting a dose-depend effective. Bovhyaluronidaze azoximer combining with antibiotics will potentiate its antimicrobial effects by destroying the microbial biofilm matrix formed by microorganisms with multidrug resistance and facilitating the penetration of antibiotics to cellular targets.
