Author(s)

Maria Nagyova¹, Leonard Siegfried¹, Daniel Jancura², Daniel Jancura², Zuzana Nadova^2*

¹Department of Medical and Clinical Microbiology, Faculty of Medicine, Pavol Jozef Safarik University, Kosice, Slovakia.
²Department of Biophysics, Institute of Physics, Faculty of Science, Pavol Jozef Safarik University in Kosice, Kosice, Slovakia.

Resistance against commonly used antibiotics is a serious clinical problem in recent medical practice. There exist several bacterial strains in which the possibilities of their inhibition are very limited due to multidrug resistance. Antimicrobial photodynamic therapy (aPDT) represents an option how to effectively suppress the growth of resistant pathogens. In this work we have studied interactions of potent photosensitizer hypericin (Hyp) with hospital-related gram positive (Gram+) and gram negative (Gram-) bacterial strains and the effects of photodynamic activated Hyp on bacterial susceptibility and/or resistance of these strains to antibiotics. We demonstrated a significant influence of photoactivated Hyp on growth of Staphylococcus aureus and Enterococcus sp. We have also shown that it is extremely important to use the effective concentrations of Hyp for aPDT, which completely inhibit the growth of microorganisms. Otherwise, there appears an increase in resistance, probably due to the activation of efflux mechanisms, which are involved in the efflux of Hyp and antibiotics as well.

Antimicrobial Photodynamic Therapy, Hypericin, Antibiotic Resistance, Methicillin-Resistant Staphylococcus aureus, Vancomycin-Resistant Enterococcus sp.

Nagyova, M. , Siegfried, L. , Jancura, D. , Jancura, D. and Nadova, Z. (2022) Effect of Photoactivated Hypericin on Growth and Antibiotic Susceptibility of Hospital-Related Staphylococcus aureus and Enterococcus sp. Clinical Strains. Advances in Biological Chemistry, 12, 116-129. doi: 10.4236/abc.2022.124010.