Membranas de quitosana contendo metabólitos produzidos pela bactérias probiótica Lactococcus lactis subsp. lactis NCDO 2118 para cicatrização de feridas de queimaduras e úlceras do pé diabético

Abstract

Chronic wounds, such as diabetic foot ulcers (DFUs) and burns, represent a significant clinical challenge due to their pathophysiological complexity and high risk of infection. In this context, chitosan-based biomaterials have stood out for their bioactive properties, including biocompatibility, antimicrobial activity, and ability to modulate the inflammatory response. In addition, postbiotics—bacterial metabolites with therapeutic effects—are emerging as a promising strategy to enhance healing. So, this study proposes the development and characterization of chitosan membranes containing postbiotics produced by the bacterium Lactococcus lactis subsp. lactis NCDO 2118 for the treatment of burn wounds and diabetic foot ulcers (DFU). The approach integrates two main stages: (1) a systematic review and meta-analysis following PRISMA 2020 guidelines, assessing methodological bias using SYRCLE and MINORS tools, to evaluate the efficacy of chitosan-based dressings; and (2) the synthesis and initial characterization of chitosan membranes loaded with bioactive metabolites (GABA and Hsp65). Meta-analysis revealed a significant effect of chitosan on wound healing (SMD = 2.48; p < 0.001), with sustained release, mechanical strength, and low contact angle identified as key predictors of therapeutic efficacy. The developed membranes showed structural integrity, flexibility, but without any significative antimicrobial activity against common pathogens in chronic wounds (Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 700603, Acinetobacter baumannii ATCC 19606 and Proteus mirabilis ATCC 15290). The combination of postbiotics with chitosan’s bioactive properties opens new perspectives for the development of more effective, safe, and low-cost therapies.