Phytochemical and Antimicrobial Exploration of Phyla dulcis Extracts: A Source of Bioactive Natural Products Against Staphylococcus aureus

Phyla dulcis (Trevir.) Moldenke, commonly known as “hierba dulce”, is a medicinal plant traditionally used in Mexican ethnomedicine for the treatment of various ailments, including gastrointestinal disorders, respiratory conditions, and inflammatory diseases. Despite its widespread traditional use, its antimicrobial potential and phytochemical composition remain insufficiently explored. In this study, the antimicrobial activity of hexane, ethyl acetate, and methanolic extracts obtained from P. dulcis was evaluated against Staphylococcus aureus using the agar diffusion method. The extracts were tested at concentrations ranging from 12.5 to 200 µg/mL, and the resulting inhibition zones were measured and compared with those produced by standard antibiotics used as positive controls. All extracts exhibited concentration-dependent inhibitory effects, although their antimicrobial activity varied according to the extraction solvent. Among them, the ethyl acetate and methanolic extracts demonstrated the highest antibacterial activity, suggesting that semi-polar and polar fractions are enriched with bioactive secondary metabolites, such as phenolic compounds, flavonoids, or terpenoids. The results highlight the antimicrobial potential of P. dulcis against S. aureus and provide scientific evidence supporting its traditional medicinal use. These findings also reinforce the importance of medicinal plants as valuable sources of bioactive compounds for the discovery of new antimicrobial agents. Further phytochemical and pharmacological studies are required to isolate, identify, and characterize the active constituents responsible for the observed antibacterial activity and to evaluate their mechanisms of action, safety, efficacy, and potential therapeutic applications.