Abstract

The increasing popularity of plant-based meat (PBM) alternatives raises novel challenges for microbiological safety, particularly against Staphylococcus contamination. This study addresses this gap by isolating and identifying Staphylococcus spp. from commercial PBM products, characterizing two polyvalent lytic Staphylococcus phages (S2G3 and Fi4S2), and assessing their biocontrol potential specifically within PBM matrices. Among 20 PBM samples collected from supermarkets in Bangkok, Thailand, 35 % were positive for Staphylococcus spp. The selected phages demonstrated broad lytic spectra against various species of Staphylococcus, notably excluding S. sciuri PSU-PC-003 and S. epidermidis WA23. Transmission electron microscopy (TEM) revealed morphological consistency of both phages as myoviruses. Whole genome sequencing (WGS) indicated genomes of approximately 153 kb with low GC content (∼34 %), encoding predominantly hypothetical proteins alongside genes essential for phage-host interactions, DNA metabolism, and structural functions. Notably, neither lysogenic nor antibiotic resistance-associated genes were detected. Stability tests demonstrated high tolerance across diverse environmental conditions, including broad pH (2−11), moderate temperature (up to 45 °C), moderate salinity (up to 5 % NaCl), and low chlorine concentrations (<1 %). The phage cocktail effectively reduced Staphylococcus contamination in artificially inoculated PBM, achieving up to a 1.8-log CFU/g reduction after three days at the highest concentration tested (10 %). This study supports phage-based strategies as viable biocontrol measures to enhance microbial safety in emerging PBM products.