Fabrication and characterization of polylactic acid coaxial antibacterial nanofibers embedded with cinnamaldehyde/tea polyphenol with food packaging potential

Polylactic acid (PLA) is a promising food packaging material with biocompatible, nontoxic and biodegradable. In order to reduce the deterioration of aquatic products caused by microorganisms, PLA coaxial nanofiber films with cinnamaldehyde (CMA), tea polyphenol (TP) and its composite as core materials were prepared by using coaxial electrospinning technology. Its microscopic morphology and structure were characterized separately, and its thermal stability, wettability and mechanical properties were determined. The antibacterial activity and antibacterial mechanism of nanofiber films were studied with Shewanella putrefaciens (S. putrefaciens) which is the dominant spoilage of aquatic products as the target of action. The results show that the CMA/TP (m/m = 2:5)-PLA coaxial nanofibers have small diameter, uniform distribution, smooth surface, no pores and fracture. At the same time, the film has strong hydrophobicity, good thermal stability and mechanical properties. Its antibacterial performance is better than that of single-core nanofiber films, which effectively destroys the cell membrane of S. putrefaciens, increases the permeability of cell membrane, and interferes with the synthesis and expression of its protein. The coaxial nanofiber films with CMA, TP and its composite as core material can be used as a fresh-keeping material with antibacterial properties, and has potential application value in the field of food preservation.