Use of cashew gum for development of LBL films with antibacterial actibity for applicantion against foodborne pathogens

Abstract

Escherichia coli are one ofthe most common etiological agents of diarrhea in developing countries. The appearance of resistant E. coliprevents these infections treatment, thus antimicrobial peptides and their biotechnological applications can make good alternatives to treat and prevent intestinal infections by these bacteria. The aim of this study was to evaluate the antibacterial activity of PcL342-354C peptide, derived from Cry1Ab16 Toxinfrom Bacillus thuringiensis, againsts trains of E. coli, as well as the synthesis, characterization and evaluation of the antibacterial activity of layer-by-layer(LbL) films containing PcL342-354C. The results showed that the PcL342-354Cpeptide inhibited the growth of E. coliATCC 25922 (Minimal Inhibitory Concentration -MIC-: 31.25 μg/mL), E. coliML1 (MIC: 31.25 μg/mL) and E. coli ATCC 35218 (MIC: 15.62 μg/mL). The Minimal Bactericidal Concentration was250 μg/mL for all strains used,proving a potential antibacterial activity against these Gram-negative bacteria. Morphological effect on E. coli,produced by Cry1Ab16 Toxin derived peptide at MIC, was significant. The morphology of the ITO/Cashew gum/PcL342-354C film was analysed using Atomic Force Microscopy (AFM) which showed an increase of roughness due to the increase in the number of layers. LbL film has antibacterial activity against E. coli NCTC 9001 in both tested conditions (10 and 20 bilayers). Our results indicate that the peptide exhibits an antibacterial potential that can be tapped to develop biomaterials with antibacterial activity for use against foodborne pathogens.