A Novel Nano-Antimicrobial Polymer Engineered with Chitosan Nanoparticles and Bioactive Peptides as Promising Food Biopreservative Effective against Foodborne Pathogen E. coli O157-Caused Epithelial Barrier Dysfunction and Inflammatory Responses.

Ming Kuang,Haitao Yu,Tao Huang,Han Chen,Mingchao Sun,Shiyan Qiao,Xiumei Shi,Jiaqi Zhang

doi:10.3390/ijms222413580

Abstract

For food quality and safety issues, the emergence of foodborne pathogenic bacteria has further accelerated the spread of antibiotic residues and drug resistance genes. To alleviate the harm caused by bacterial infections, it is necessary to seek novel antimicrobial agents as biopreservatives to prevent microbial spoilage. Nanoantimicrobials have been widely used in the direct treatment of bacterial infections. CNMs, formed by chitosan nanoparticles and peptides, are promising antibiotic alternatives for use as excellent new antibacterial drugs against pathogenic bacteria. Herein, the current study evaluated the function of CNMs in the protection of foodborne pathogen Escherichia coli (E. coli) O157 infection using an intestinal epithelial cell model. Antibacterial activity assays indicated that CNMs exerted excellent bactericidal activity against E. coli O157. Assessment of the cytotoxicity risks toward cells demonstrated that 0.0125–0.02% of CNMs did not cause toxicity, but 0.4% of CNMs caused cytotoxicity. Additionally, CNMs did not induced genotoxicity either. CNMs protected against E. coli O157-induced barrier dysfunction by increasing transepithelial electrical resistance, decreasing lactate dehydrogenase and promoting the protein expression of occludin. CNMs were further found to ameliorate inflammation via modulation of tumor factor α, toll-like receptor 4 and nuclear factor κB (NF-κB) expression via inhibition of mitogen-activated protein kinase and NF-κB activation and improved antioxidant activity. Taken together, CNMs could protect the host against E. coli O157-induced intestinal barrier damage and inflammation, showing that CNMs have great advantages and potential application as novel antimicrobial polymers in the food industry as food biopreservatives, bringing new hope for the treatment of bacterial infections.

Highlights

Despite the development and application of a large number of antibiotics, bacterial infections continue to pose a serious threat to human health; for instance, morbidities and mortality increases in intestinal inflammatory disease (IBD) induced by enteric diseases are universal problems [1,2,3,4]
The results show that CNMs did not cause cytotoxicity to intestinal epithelial cell (IPEC)-J2 even though they were 4 × minimum inhibitory concentration (MIC)
We evaluated the potential protective capacity of CNMs, a novel antimicrobial engineered with antimicrobial peptides and chitosan nanoparticles, against foodborne pathogenic E. coli O157 infection in an IPEC-J2 cell model

Summary

Introduction

Despite the development and application of a large number of antibiotics, bacterial infections continue to pose a serious threat to human health; for instance, morbidities and mortality increases in intestinal inflammatory disease (IBD) induced by enteric diseases are universal problems [1,2,3,4]. For severe drug-resistant bacterial infections, it is important to develop an effective treatment strategy. To meet the growing consumer demand for safe ready-to-eat foods, an attractive alternative to chemical preservatives is needed. Among these emerging approaches, nano-antimicrobials show great potential in the treatment of severe drug-resistant bacterial infections due to their excellent size effect, specific physicochemical properties and ease of modification [13]

Methods

Results

Discussion

Conclusion