Nisin adsorption on hydrophilic and hydrophobic surfaces: evidence of its interactions and antibacterial activity

Abstract

Study of peptides adsorption on surfaces remains a current challenge in literature. A complementary approach, combining X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to investigate the antimicrobial peptide nisin adsorption on hydrophilic and hydrophobic surfaces. The native low density polyethylene was used as hydrophobic support and it was grafted with acrylic acid to render it hydrophilic. XPS permitted to confirm nisin adsorption and to determine its amount on the surfaces. ToF-SIMS permitted to identify the adsorbed bacteriocin type and to observe its distribution and orientation behavior on both types of surfaces. Nisin was more oriented by its hydrophobic side to the hydrophobic substrate and by its hydrophilic side to the outer layers of the adsorbed peptide, in contrast to what was observed on the hydrophilic substrate. A correlation was found between XPS and ToF-SIMS results, the types of interactions on both surfaces and the observed antibacterial activity. Such interfacial studies are crucial for better understanding the peptides interactions and adsorption on surfaces and must be considered when setting up antimicrobial surfaces.

Dual functional nisin-multi-walled carbon nanotubes coated filters for bacterial capture and inactivation

“…The majority of the residues in the N-terminal are hydrophobic except a single charged residue Lys 12, whereas the C-terminal contains most charged and hydrophilic residues [ 36 ]. Upon absorption on MWCNTs’ surfaces, nisin molecules were mostly oriented with their hydrophobic side facing to the hydrophobic substrate and their hydrophilic side facing to the outer layers of the adsorbed peptide, which is in contrast to the observation on the hydrophilic substrates [ 37 ]. Such molecular orientation contributed to the high hydrophilic property (the lower contact angles) on the MWCNTs-nisin surfaces.…”

Application of Nanofibrillated Cellulose on BOPP/LDPE Film as Oxygen Barrier and Antimicrobial Coating Based on Cold Plasma Treatment

“…The decrease in SWCA after plasma treatment clearly indicates that the surface of the LDPE is transformed from hydrophobic to hydrophilic as compared with the untreated film. Several studies attribute the change in hydrophilicity to the generation of polar function groups on the surface of LDPE by oxygen plasma [16,37,38]. The change of surface chemistry before and after plasma treatment could also be revealed by AFM phase images as shown Figure 1b,c.…”

Variable Characteristics of Bacteriocin-Producing Streptococcus salivarius Strains Isolated from Malaysian Subjects

“…Lactic acid bacteria are generally considered to be non-pathogenic (with some exceptions such as Streptococcus mutans which causes dental caries) and can produce different kinds of bacteriocins such as nisin produced by Lactococcus lactis [4]–[7], plantaricins produced by Lactobacillus plantarum [8]–[10], mutacins produced by Streptococcus mutans [11]–[15] and salivaricins produced by Streptococcus salivarius [16]–[20]. S. salivarius is a species of lactic acid bacteria colonizing the human oral cavity [21].…”