Background and Aim: Prebiotics are a group of nutrients or compounds that are degraded by the gut microbiota, including Lacticaseibacillus paracasei. The probiotic plays an important role in adhesion to the gut and is able to produce antimicrobial substances to inhibit pathogens. This study aimed to investigate the effects of Sangyod rice bran extract on the growth promotion of L. paracasei. Furthermore, antibacterial activity of the extract and L. paracasei supernatants cultured in De Man, Rogosa and Sharpe (MRS) medium plus the extract against zoonotic and foodborne pathogens was investigated. Materials and Methods: Antibacterial activity of the crude extract and the oil from Sangyod rice bran against the pathogens, including Bacillus cereus, Staphylococcus aureus, Escherichia coli, Avian pathogenic E. coli, and Pseudomonas aeruginosa was investigated using broth microdilution assay. The effects of the crude extract and the oil on the growth and adhesion of L. paracasei were further determined. The antibacterial activity of L. paracasei supernatant cultured in the medium supplemented with the extract and the oil against the pathogens was determined by agar well diffusion assay, followed by the broth microdilution assay. Finally, the chemical constituents and antioxidant activity of the crude extract and the oil from Sangyod rice bran were investigated. Results: The crude extract and the oil from Sangyod rice bran enhanced L. paracasei growth during the exponential phase. Furthermore, the crude extract at 0.25 mg/mL significantly enhanced the adhesion of L. paracasei to the surface compared with the control. Both minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of the crude extract against B. cereus and S. aureus were 0.5 and 1.0 mg/mL, respectively. All pathogens were sensitive to the supernatant of L. paracasei with similar MIC and MBC ranging from 12.5% v/v to 50% v/v. However, the MIC and MBC values of L. paracasei supernatant grown in MRS medium plus the crude extract and oil were not significantly different compared to the supernatant obtained from MRS alone. The crude extract had free radical scavenging activities with IC50 values at 0.61 mg/mL. Conclusion: The results suggested the potential benefits of the crude extract from Sangyod rice bran for inducing the growth and the adhesion of L. paracasei and inhibiting zoonotic and foodborne pathogens.

The prevention and controlled growth of pathogenic bacteria on eggs during storage and distribution at room temperature is important to ensure commercial eggs and egg products are safe for consumer. This study investigated the combined effects of orange oil (0.001%–0.004% v/w) and smoke for 10 min in paper egg tray packaging produce from the fungal pulp of Trametes versicolor. Eggs were kept in the developed paper egg tray at room temperature (30 ± 2°C). The mechanism of the combined antibacterial effects against Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus and egg quality were investigated. The combination of orange oil (0.004%) and smoke delayed all bacteria and suppressed changes in weight loss and the quality factor of eggs (Haugh unit, yolk index, albumen index) for at least 14 d. It was found that the volatile orange oil smoke in the egg tray could be passed through the structure of the cell wall and membrane of bacteria, giving rise to loss of cell viability by irreversibly damaging the cell membranes of all the bacteria in this test. Moreover, higher antioxidant activity was found on the eggs than on the eggshells, which is linked to greater shelf-life of treated eggs. The study demonstrates an improved paper egg tray packaging system and the possibility of combining released essential oils and smoke, which can be extended to egg products. Smoke can also be modified on the surface of paper egg trays easily, which shows potential in functionalizing implanted materials with antibacterial properties.

Background: Avian pathogenic Escherichia coli (APEC) contributes substantially to colibacillosis outbreaks in chickens. Because APEC cells readily attach to surfaces and develop biofilms, they pose a notable hazard to poultry production and food safety. This study investigated the antibiofilm and anti-adhesion activities of deep eutectic solvent-based emulsion containing Piper betle L. extract (DEPE) and hydroxychavicol, a pure compound isolated from P. betle leaves against APEC. Methods: Antibiofilm and anti-adhesion activities of DEPE and hydroxychavicol against APEC were investigated. Molecular docking and dynamics simulation of DEPE and hydroxychavicol was conducted. In addition, anti-adhesion activity of DEPE on chicken meat during storage was evaluated. Results: DEPE and hydroxychavicol significantly inhibited biofilm formation at sub-MIC, with DEPE achieving up to 80% inhibition and hydroxychavicol up to 69%. At 8 × MIC, DEPE and hydroxychavicol diminished the viability of both early and established biofilms. Furthermore, DEPE and hydroxychavicol reduced APEC adhesion on the surface as observed by SEM. In silico analyses demonstrated the stable binding of hydroxychavicol to adhesion-related proteins, particularly EcpA and FimH, suggesting a possible mechanism for its anti-adhesion activity. At day 5, DEPE at 4 × MIC significantly reduced 63% bacterial adhesion to chicken meat surfaces during storage, while maintaining the meat’s color. Conclusions: These findings indicate that DEPE and hydroxychavicol are promising candidates for limiting APEC biofilm formation and surface attachment and may serve as alternative antibacterial agents in poultry-related food safety applications.