Infection and Drug Resistance (Oct 2019)
Different Effects Of Amniotic Membrane Homogenate On The Growth Of Uropathogenic Escherichia coli, Staphylococcus aureus And Serratia marcescens
Abstract
Tina Šket,1 Taja Železnik Ramuta,1 Marjanca Starčič Erjavec,2 Mateja Erdani Kreft1 1Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia; 2Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, SloveniaCorrespondence: Mateja Erdani KreftFaculty of Medicine, Institute of Cell Biology, University of Ljubljana, Vrazov trg 2, Ljubljana SI-1000, SloveniaTel +386 1 543 76 85Fax +386 1 543 76 81Email [email protected]: Due to the emergence and spread of bacterial strains resistant to antibiotics, the development of new antimicrobials is imperative. The antimicrobial effect of the amniotic membrane (AM) has been explored to a limited extent so far.Materials and methods: We collected 12 biological samples of AM homogenates and tested their antimicrobial effect on 4 pathogens, including the clinical strain of uropathogenic Escherichia coli (UPEC), the wild-type strain of Staphylococcus aureus, and the wild-type strain and a clinical strain of Serratia marcescens. To quantify the antibacterial effect of AM, we monitored the effect of AM homogenate on bacterial growth using plate count method and agar diffusion method. Additionally, minimal inhibitory concentrations (MICs) for AM homogenate dilutions were determined and S. marcescens growth in AM homogenate alone was evaluated.Results: Our results demonstrated that AM homogenate had a bacteriostatic effect on studied UPEC and S. aureus. Interestingly, when used in lower concentrations, the AM homogenate had a bactericidal effect on both strains. In contrast, S. marcescens was completely resistant to the growth-inhibitory substances of AM homogenate. Its growth was slightly accelerated in liquid culture medium in the presence of AM homogenate and the strain was able to grow in undiluted, 2-fold and 4-fold diluted AM homogenate.Conclusion: Obtained results illustrated that AM homogenate could be a candidate for treatments and prevention of UPEC and S. aureus infections, but not that of S. marcescens, whose growth is enhanced by AM homogenate. Moreover, the established liquid culture medium assay can be used as a time- and cost-effective method for a personalized evaluation of drug effect on the growth of chosen bacterial strains with parallel testing of resistance or susceptibility to multiple drugs. The susceptibility of bacteria to AM homogenate in solid and liquid culture media is encouraging for its use in biomedical applications.Keywords: antimicrobial agent, growth inhibition, liquid culture medium, agar diffusion method, bacteriostatic, bactericidal
