Melittin Inhibition and Eradication Activity for Resistant Polymicrobial Biofilm Isolated from a Dairy Industry after Disinfection

Abstract

The emerging concern about the increase of antibiotic resistance and associated biofilm has encouraged scientists to look for alternative antibiotics such as antimicrobial peptides (AMPs). This study evaluated the ability of melittin to act as an antibacterial biofilm inhibitor and biofilm remover considering isolates from dairy industry. Minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs), minimum biofilm inhibitory concentrations (MBICs), and biofilm removal activities were studied in polymicrobial biofilms produced from isolates. MIC and MBC were set at 1–3 µg/mL and 25–50 µg/mL for Gram-positive and Gram-negative bacteria, respectively. Results demonstrated a good MBIC reaching 85% inhibition ability and a good activity and better penetration in deeper layers against the mixed preformed biofilm, thereby increasing its activity against all isolates also at the lowest tested concentrations. Melittin showed interesting characteristics suggesting its potential to act as an antimicrobial agent for polymicrobial biofilm from dairy industry even in environmental isolates.

Synergistic activity of melittin with mupirocin: A study against methicillin-resistant S. Aureus (MRSA) and methicillin-susceptible S. Aureus (MSSA) isolates

“…The anti-biofilm activities of AMPs are not completely understood. They may affect matrix disruption, binding of DNA, and altering the expression of biofilm-related genes, such as the production of pili, QS systems, cytoplasmic membrane, and flagella assembly or several of these mechanisms ( Park et al, 2014 , Issam et al, 2015 , Galdiero et al, 2019 ).…”

Antimicrobial Susceptibility Testing of Antimicrobial Peptides to Better Predict Efficacy

“…Similarly, the peptidomimetic mPE was able to disrupt the membrane of Candida albicans growing as biofilms (PI uptake) at concentrations 6–12-fold higher (50–100 mg/L) than the MIC vs. planktonic cells (Hua et al, 2010 ). Studies of the activity of AMP vs. polymicrobial biofilms are less frequently reported, but the Herpes simplex-derived AMP gH625-GCGKKKK was able to prevent formation of mixed species biofilms consisting of Candida tropicalis and S. aureus or C. tropicalis and Serratia marcescens as well as eradicating mixed biofilms containing these microbes (de Alteriis et al, 2018 ) as did melittin against a polymicrobial biofilm consisting of selected dairy isolates of bacteria ( P. aeruginosa, Staphylococcus haemolyticus, K. pneumoniae , and Aeromonas caviae ) (Galdiero et al, 2019 ). The de novo AMP ASP-1 was able to eradicate polymicrobial biofilms containing S, aureus, P. aeruginosa, A. baumannii , and K. pneumoniae when formulated into a polyurethane-based dressing (Bayramov et al, 2018 ) and the Komodo dragon-derived peptide DRGN-1 demonstrated moderate eradication activity against mixed biofilms containing P. aeruginosa and S. aureus (Chung et al, 2017 ).…”

Allium ursinum and Allium oschaninii against Klebsiella pneumoniae and Candida albicans Mono- and Polymicrobic Biofilms in In Vitro Static and Dynamic Models

“…A previously described biofilm assay was performed to assess biofilm formation by examined strains, in 96-well polystyrene plates according to Stepanović et al [33,34].…”