Carbohydrate nanoparticle-based delivery system as carrier to prolong the efficacy of antimicrobial peptides
Abstract
The prolonged efficacy of antimicrobial peptides is important for reducing the risk of pathogen contamination and thus improving food safety. In this work, nisin and epsilon-poly-L-lysine (EPL) were used as the peptide models, Listeria monocytogenes and E. coli O157:H7 were selected as pathogen models. Phytoglycogen (PG), a dendrimer-like carbohydrate polymer from maize mutant was used to prepare phytoglycogen octenyl succinate (PG-OS), an amphiphilic, negatively charged nanoparticle to deliver antimicrobial peptides. Two types of delivery system were designed and tested: nanoparticle dispersion and nanoparticle-stabilized emulsion. The result showed that PG-OS nanoparticles were effective to prolong the efficacy of nisin against Listeria, and PG-OS-stabilized emulsion was superior to prolong the efficacies of both nisin and EPL against Listeria and E. coli, respectively. For example, PG-OS emulsion retained an effective inhibitory activity of nisin against Listeria after 50 days storage, compared with only 5 days for nisin only. In addition, PG-OS emulsion retained an effective inhibition of EPL against E. coli for over 20 days, compared with 10 days of EPL-only solution. To understand the retention of peptides with delivery systems, the adsorption and availability of peptides was also studied using other approaches. In general, this work demonstrated a novel strategy to enhance food safety and may also benefit other application areas.
Degree
Ph.D.
Advisors
Yao, Purdue University.
Subject Area
Food Science
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