Zein Nanoparticles Containing Arginine-Phenylalanine-Based Surfactants: Stability, Antimicrobial and Hemolytic Activity

Abstract

Although cationic surfactants have a remarkable antimicrobial activity, they present an intrinsic toxicity that discourages their usage. In this work novel zein nanoparticles loaded with arginine-phenylalanine-based surfactants are presented. The nanoparticles were loaded with two single polar head (LAM and PNHC12) and two with double amino acid polar head surfactants, arginine-phenylalanine (C12PAM, PANHC12). The formulations were characterized and their stability checked up to 365 days. Furthermore, the antimicrobial and hemolytic activities were investigated. Finally, NMR and molecular docking studies were carried out to elucidate the possible interaction mechanisms of surfactant-zein. The nanoparticles were obtained with satisfactory size, zeta potential and dispersibility. The surfactants containing arginine-phenylalanine residues were found to be more stable. The nanoencapsulation maintained the antimicrobial activities unaltered in comparison to the surfactants’ solutions. These results are in agreement with the NMR and docking findings, suggesting that zein interacts with the surfactants by the aromatic rings of phenylalanine. As a result, the cationic charges and part of the aliphatic chains are freely available to attack the bacteria and fungi, while not available to disrupt the cellular membranes. This approach opens new possibilities for using cationic surfactants and benefits from their extraordinary antimicrobial responses for several applications.

Zein Nanoparticles Containing Arginine-Based Surfactants: Physicochemical Characterization and Effect on the Biological Properties

“…In fact, the NpC 9 (LA) 2 -nanoparticles were not active against any bacteria tested unlike its solution, which presented still a good activity. The same behavior has been observed when phenylalanine-arginine surfactants were loaded to the zein nanoparticles [34].…”

“…This reduction in the hemolytic activity for the nanoparticles can be due to the interactions found between the hydrophobic residues of the zein and the hydrophobic regions of the surfactant, which would make the surfactant more internalized or immobilized. This internalization would induce the reduction of both the antimicrobial properties and the hemolytic activity [34]. This behavior can be also related to the morphology and size of the aggregates formed by every compound.…”

“…Few cases of low/lack of activity of the surfactant-nanoparticles were observed. The development of antibacterial nanoparticles is a promising approach for combating drug resistance [34]. Most of the antibiotic resistance mechanisms are irrelevant for antibacterial nanoparticles because the mode of action of these aggregates mainly involves direct contact with the bacterial cell wall and its disruption.…”

Phenylalanine and Tryptophan-Based Surfactants as New Antibacterial Agents: Characterization, Self-Aggregation Properties, and DPPC/Surfactants Vesicles Formulation

“…Molecular docking studies were carried out to understand the observed antimicrobial activities of the prepared surfactants and to shed light on the binding modes between docked ligands and enzyme targets [ 69 , 70 , 71 ].…”

“…bial activities of the prepared surfactants and to shed light on the binding modes between docked ligands and enzyme targets [69][70][71].…”