Phagovet

Anti-Salmonella polyvinyl alcohol coating – phage PBSE191

Antibiotic resistance is a growing concern in the food industry, leading to the search for alternative methods to combat bacterial contamination.

One such method is the use of bacteriophages, viruses that specifically infect and kill bacteria.

In a new study, the bacteriophage PBSE191 was characterized and applied to a polyvinyl alcohol (PVA) film.

The phage was found to belong to the Caudoviricetes class and exhibited strong lytic activity against a range of Salmonella isolates, including six different serotypes. It was also able to reduce the bacterial population by 99% within 25 minutes of exposure.

When applied to a 10% PVA film containing 20% sorbitol, the phage remained stable under dry conditions and showed strong antibacterial activity, reducing the bacterial population by 2.0 x 105 CFU/film within 2 hours.

Additionally, when applied as a coating on chicken eggshells, the PBSE191-containing PVA film was able to significantly reduce Salmonella contamination within 24 hours.

These results suggest that the PBSE191 phage has potential as a biocontrol agent for use in food safety applications.

The authors Sangbin Kim, and Yoonjee Chang published their findings in the article ‘Anti-Salmonella polyvinyl alcohol coating containing a virulent phage PBSE191 and its application on chicken eggshell‘, dated 1 December 2022.

Key topics include:

  • The use of bacteriophages as an alternative to antibiotics in the food industry is being explored due to the increase of antibiotic-resistant bacteria.
  • The bacteriophage PBSE191 was characterized and applied to a polyvinyl alcohol film.
  • PBSE191 belongs to the Caudoviricetes class and exhibited strong lytic activity against a range of Salmonella isolates.
  • When applied to a 10% PVA film containing 20% sorbitol, the phage remained stable and showed strong antibacterial activity.
  • The PBSE191-containing PVA film was able to significantly reduce Salmonella contamination on chicken eggshells within 24 hours.
  • The phage remained stable in dry conditions and was strongly released in the polymer.
  • The PBSE191 phage has high potential as a biocontrol agent for use in food safety applications.
Anti-Salmonella polyvinyl alcohol coating containing a virulent phage PBSE191

Abstract

The use of antibiotics in the food industry is avoided due to the increase of antibiotic-resistant bacteria.

Therefore, the bacteriophage is emerging as an alternative agent.

Here, we characterized the Salmonella Enteritidis phage PBSE191 and applied it to a polyvinyl alcohol (PVA) film.

Transmission electron microscopic analysis revealed that it belonged to the Caudoviricetes class, with an icosahedral head and flexible tails.

The phage showed rapid and strong lytic activity within 1 h.

It was active against a broad range of Salmonella isolates, including six serotypes.

In 25 min, 99 % of the initial population was adsorbed to the bacterial cell surface.

The phage was also applied to 10 % (w/v) PVA films and coatings, which were then characterized in terms of phage stability and antibacterial performance, both in vitro and in foods.

The phage remained stable in the 10 % (w/v) PVA solution containing 20 % (w/w, based on PVA weight) sorbitol (PVAS20), indicating that the phage was stable under dry conditions and strongly released in the polymer.

Furthermore, significant bacterial cell reduction (2.0 × 105 CFU/film within 2 h) was observed in the phage-containing PVAS20 films.

In addition, the PBSE191-containing PVAS20 coating on the chicken eggshell surface showed significant anti-Salmonella efficiency (about 2 log CFU reduction) within 24 h.

Overall, the PBSE191 phage possesses a high potential as a biocontrol agent for use as an additive, or as an active antibacterial packaging to improve food safety against Salmonella contamination.

Keywords: Antibacterial; Bacteriophage; Chicken eggs; Coating; Phage film; Polyvinyl alcohol; Salmonella.

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