Antimicrobial resistance is an imminent threat to the effective prevention and treatment of
bacterial infections and alternative antimicrobial strategies are desperately needed.
Antimicrobial peptides (AMPs) may be promising alternatives to current
antibiotics or act as adjuvants to enhance
antibiotic potency. Additionally, the use of biodegradable
lipid nanoparticles can enhance the antibacterial activity of
antibiotics and
antimicrobial peptides. In this study, the interaction of the AMPs,
nisin Z and
melittin, with conventional
antibiotics was investigated on Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. The effectiveness of nanostructured
lipid carriers (NLCs) for the entrapment of
nisin Z was also evaluated. Findings revealed that
nisin Z exhibited additive interactions with numerous conventional
antibiotics. Notable synergism was observed for
novobiocin-
nisin Z combinations. The addition of the non-
antibiotic adjuvant
EDTA significantly improved the antimicrobial activity of free
nisin Z towards E.coli. NLCs containing
nisin Z were effective against Gram-positive species at physiological pH, with an increase in effectiveness in the presence of
EDTA. Results indicate that
nisin Z may be advantageous as an adjuvant in antimicrobial
chemotherapy, while contributing in the battle against antibiotic resistance. NLCs have the potential to enhance the antibacterial activity of
nisin Z towards Gram-positive bacterial species associated with skin
infections.