Thermal treatment increases the antimicrobial activity of tepejilote rachis against <i>Pseudomonas aeruginosa</i> and <i>Staphylococcus aureus</i>

We investigate the potential of <i>Chamaedorea tepejilote</i> Liebm (tepejilote rachis) as an antimicrobial agent against <i>Staphylococcus aureus</i> and <i>Pseudomonas aeruginosa</i> strains and how thermal treatment affects its antimicrobial activity. The results showed that the thermal treatment before obtaining the extracts reduced the proliferation of microorganisms. For <i>Staphyloccoccus aureus</i>, it was observed that hydrothermal treatment before obtaining the aqueous extracts reduced the proliferation of microorganisms, while for the hexane extracts, an increase in antimicrobial activity against <i>Pseudomonas aeruginosa</i> and <i>Staphylococcus aureus</i> was obtained in the samples subjected to microwave treatment before the extraction process. A 50% reduction in the MIC against <i>Pseudomonas aeruginosa</i> was achieved with tepejilote rachis treated in the microwave prior to extraction (0.18 mg/mL versus 0.36 mg/mL). The thermal treatments resulted in a higher leakage of intracellular material in the four strains tested, and an increase in cell membrane permeability was also observed in <i>Pseudomonas aeruginosa</i>.