The study was conducted with six strains of S. enterica and six strains of the B. cereus group from the culture collection of the Laboratory of Food Microbiology and Food Preservation (LFMFP) at Ghent University (UGent; Ghent, Belgium) (Table 1 ). All strains were stored at −75°C on glass beads and revived in 9 ml of brain heart infusion broth (BHI; Oxoid, United Kingdom) overnight at 37°C (S. enterica) and 30°C (B. cereus) before use. Loops of the overnight cultures were streaked on the surface of Xylose Lysine Deoxycholate (XLD) agar (Oxoid) or Mannitol Egg Yolk Polymyxin (MYP) agar (Oxoid) plates to check the purity of Salmonella and B. cereus group strains, respectively. After incubation for 24 h, a single colony on each selective agar plates (XLD or MYP) was transferred to BHI slants [37 g/L BHI and 16 g/L bacteriological agar (Oxoid)] and incubated for 24 h at 30°C or 37°C, and kept as work stocks for maximum 6 weeks.
The PPP XenTari® WG was kindly provided by Valent BioSciences LCC (Libertyville, IL, United States), for experimental testing. The XenTari® WG selected for the study was the Water Dispersible Granule powder formulation that contains spores of BTa ABTS-1857 and insecticidal toxin proteins. For BTa ABTS-1857 spores inoculum, the powder was dissolved in sterile distilled water and further diluted until the desired concentration. For BTa ABTS-1857 vegetative cells inoculum, the B. thuringiensis strain was isolated from the XenTari® WG powder by plating the dissolved product on MYP agar and incubating for 24 h at 30°C. One single colony was selected, streaked on MYP agar, and then grown on BHI slants at 30°C for 24 h and kept as work stocks for maximum 6 weeks.
The PPP XenTari® WG was kindly provided by Valent BioSciences LCC (Libertyville, IL, United States), for experimental testing. The XenTari® WG selected for the study was the Water Dispersible Granule powder formulation that contains spores of BTa ABTS-1857 and insecticidal toxin proteins. For BTa ABTS-1857 spores inoculum, the powder was dissolved in sterile distilled water and further diluted until the desired concentration. For BTa ABTS-1857 vegetative cells inoculum, the B. thuringiensis strain was isolated from the XenTari® WG powder by plating the dissolved product on MYP agar and incubating for 24 h at 30°C. One single colony was selected, streaked on MYP agar, and then grown on BHI slants at 30°C for 24 h and kept as work stocks for maximum 6 weeks.
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