| الملخص: | The effects of high-hydrostatic pressure (HP) treatments (450 and 600 megapascals, MPa, for 5 min at temperatures of 22 °C and 50 °C) on the microbiota of a coriander and parsley dressing was studied via culture-dependent and culture-independent approaches. Samples were refrigerated for 20 days, with periodic counts of the culture media supplemented with, or without, antimicrobials. HP-treated samples showed significantly lower viable cell counts compared to untreated controls. Only the control samples yielded bacterial growth on media with antimicrobials (imipenem, cefotaxime, benzalkonium chloride), including mostly <i>Pseudomonas</i> and <i>Lactobacillus</i>. <i>Bacillus</i> and <i>Paenibacillus</i> were identified from pressurized samples. Few isolates showed higher tolerance to some of the biocides tested. Pseudomonads showed outstanding resistance to meropenem and ceftazidime. According to high-throughput sequencing analysis, the microbiota of the dressing control samples changes during storage, with a reduction in the relative abundance of <i>Proteobacteria</i> and an increase in <i>Firmicutes</i>. The composition of the residual microbiota detected during storage was highly dependent on the pressure applied, and not on the treatment temperature.
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