Multiphasic Antibiofilm Dynamics and Antimicrobial Efficiency of Wild Albanian Origanum vulgare L. subsp. vulgare Extract Against Uropathogens

Nowadays, urinary tract infections constitute a major clinical challenge due to rising antimicrobial resistance and the limited efficacy of conventional therapies. This preliminary study evaluated the antioxidant and antimicrobial potential of an alcoholic extract of a wild Albanian Origanum vulgare L. subsp. vulgare against uropathogens. The alcoholic dry extract demonstrated a promising composition, with a relatively high total phenolic content (TPC) of 344.47 mg GAE/g DW, accompanied by considerable antioxidant activity as determined by the FRAP, ABTS, and DPPH assays, and an HPLC-ESI-MS analysis revealed rosmarinic acid as the predominant phenolic compound (42.43 mg/g of dry extract), which drives the bioactivity alongside co-extracted volatile monoterpenes. The remaining quantified phenolic compounds occurred at markedly lower concentrations. Broth microdilution assays revealed broad bactericidal and fungicidal activity against both Gram-negative (Escherichia coli, Enterobacter cloacae, Proteus mirabilis, P. vulgaris, Klebsiella pneumoniae, Pseudomonas aeruginosa, Serratia marcescens, Salmonella Typhimurium) and Gram-positive (Staphylococcus aureus) bacteria, as well as Candida albicans, with MIC and MBC/MFC values stabilizing between 2.0 and 4.0 mg/mL. Furthermore, the extract effectively inhibited early-stage biofilm formation, yielding relatively low MBIC50 targets (<0.00195 mg/mL) for highly sensitive strains (E. coli, S. marcescens, S. Typhimurium), while challenging pathogens (P. aeruginosa, E. cloacae) exhibited a non-linear, biphasic hormetic response. These findings validate this wild-type Albanian oregano population as a promising source of polyphenol-rich, multi-target bioactive complexes for advanced biomedical applications in the management of urinary tract infections (UTIs).