Lactoferrin-Chitosan-TPP Nanoparticles: Antibacterial Action and Extension of Strawberry Shelf-Life

Abstract

The aim of the present study was to produce lactoferrin (L) and chitosan (C) nanoparticles by ionic crosslinking with TPP and thereby increase the antimicrobial activity of biopolymers. The nanoparticles were synthesized in different proportions of biopolymers and TPP and characterized regarding their size, zeta potential, morphology, chemical interactions, structural characteristics and antibacterial activity. They were also applied as coatings on strawberries with the aim of increasing fruit shelf-life. Circular dichroism spectra revealed that the addition of TPP altered the secondary structure of lactoferrin. The nanoparticles 3.5L:5.5C:1TPP and 4.5L:4.5C:1TPP showed higher zeta potential values and lower hydrodynamic diameters (+39.30 mV, 81.87 nm and + 33.07 mV, 97.67 nm, respectively) and intense bacteriostatic action against S. aureus (0.0370 mg/ml and 0.0463 mg/ml, respectively).The minimum inhibitory concentration of these nanoparticles was three times lower than those of pure biopolymers. When applied to strawberries coating, the nanoparticles delayed the ripening and degradation of the fruit. These results con rm that it is possible to intensify the antimicrobial properties of lactoferrin and chitosan through ionic crosslinking with TPP and, thus, expand their use as natural food preservatives.

Improving chitosan properties through ionic and chemical cross‐linking and their impact on emulsified systems

“…The transmission electron microscope LEO 906 (ZEISS, Germany) was used to investigate the morphology of CS particles and to evaluate their size and was based on the methodology of Duarte et al . (2023).…”

“…The MIC was evaluated according to the method described by Duarte et al . (2023). The MBC was determined by the agar plate method adapted from Yue et al .…”

“…The size results were presented as the mode of number size distribution. The transmission electron microscope LEO 906 (ZEISS, Germany) was used to investigate the morphology of CS particles and to evaluate their size and was based on the methodology of Duarte et al (2023). Spectra of CS particles and pure materials added of 1% (w w À1 ) KBr were obtained in the FTIR spectrophotometer IRPrestige-21 (Shimadzu, Japan) from 4000 to 400 cm À1 with a resolution of 4 cm À1 .…”

“…The strains were donated by the Department of Food Science of The University of Campinas. The MIC was evaluated according to the method described by Duarte et al (2023). The MBC was determined by the agar plate method adapted from Yue et al (2021).…”

Effect of dielectric barrier discharge cold plasma on the bio-nanocomposite film and its potential to preserve the quality of strawberry under modified atmosphere packaging

“…Strawberry is a perishable fruit and its shelf life is not too much due to the physiological properties (Duarte et al, 2023). Modified atmosphere packaging (MAP) is a well-proven method to extend the life of fresh fruit and vegetables (Alzuabi et al, 2023;Olveira-Bouzas et al, 2023. Although several research has been carried out on the effect of MAP on the shelf life of strawberries under different material films condition (Robles-Flores et al, 2018;de Oliveira Filho et al, 2022;pasha et al, 2023) no study (to the best of our knowledge) has been performed on the effect of cold plasma on the packaging film based on cellulose/chitosan nano-composite that leads to influence on the quality of strawberries.…”