Potential application of prickly pear vinegar as a surface disinfectant: in vitro and molecular docking studies

The surface disinfectant property of a homemade prickly pear vinegar (PPV) is investigated throughout this study, using in vitro testes assisted by a molecular docking study, against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli and Salmonella enterica) strains. Results show that PPV exhibited growth-inhibitory effect for all tested bacterial strains at MIC values ranging between 1.56, and 3.12% (v/v). Obtained results showed that PPV was more effective to inhibit initial cell attachment (86.33, 54.15, and 72.19% at 2×MIC) compared to 24h-preformed biofilms (67.64, 42.69 and 39.94% at 2×MIC). Treatment of abiotic surface with PPV at 2×MIC resulted in a significant reduction (p < 0.05) of bacterial metabolic activity (72.10, 52.92 and 56.96%, respectively). The anti-biofilm activity of PPV was also evaluated on two additional abiotic surfaces such as glass and stainless steel and results showed that treatment of biofilms with PPV at 2×MIC (% v/v) resulted in a log reduction of the initial biomass. Molecular docking analysis predicted the ability of phenolic compounds present in PPV, particularly, rutin to interact with SarA protein involved in S. aureus biofilm formation.