Exploring the Antibacterial Potency of Cymbopogon Essential Oils: Liposome Encapsulation and Phytochemical Insights

<b>Background</b>: Antimicrobial resistance (AMR) represents a critical global health challenge, requiring innovative strategies to combat resistant bacterial strains. <i>Cymbopogon</i> essential oils (EOs) are promising natural antimicrobial agents. <b>Methods</b>: The EO of <i>Cymbopogon commutatus</i> was extracted by hydrodistillation from fresh aerial parts and compared to commercial EOs from <i>C. citratus</i>, <i>C. nardus</i>, and <i>C. winterianus</i>. Antibacterial activity was evaluated against seven bacterial strains (two Gram-positive and five Gram-negative). Both water-soluble fractions and liposome-encapsulated formulations were tested. Liposomes were prepared using soybean lecithin, and their stability was assessed by dynamic light scattering (DLS). The chemical composition of the pure EOs, water-soluble fractions and non-water-soluble fractions was analyzed by gas chromatography-mass spectrometry (GC-MS). <b>Results</b>: Liposome encapsulation improved EO solubility in aqueous media and significantly enhanced antibacterial efficacy, reducing minimum inhibitory concentration (MIC) values compared to the water-soluble fractions (MICs ≥ 25%). Among the tested formulations, the liposome containing <i>C. citratus</i> EO exhibited the strongest inhibitory effect against <i>Staphylococcus aureus</i> (MIC: 0.04%) followed by liposomes with <i>C. nardus</i> and <i>C. commutatus</i> (MIC: 0.08%). Against <i>Enterococcus faecalis</i>, the most effective formulation was the liposome containing <i>C. winterianus</i> EO (MIC: 0.02%), followed by <i>C. citratus</i> (MIC: 0.08%). The liposome formulated with <i>C. winterianus</i> maintained its particle size over 72 h without phase separation. GC-MS analysis revealed distinct phytochemical profiles: <i>C. commutatus</i> EO was rich in piperitone (73.9%) and <i>C. citratus</i> was rich in (Z)-(3,3-Dimethyl)-cyclohexylideneacetaldehyde (39.9%) and citral (32.5%), while <i>C. nardus</i> and <i>C. winterianus</i> were dominated by geraniol (21.5%) and citronellal (30.8%), respectively. Notably, piperitone, the major compound in <i>C. commutatus</i> EO, exhibited strong antibacterial activity against <i>S. aureus</i> (MIC of <0.04%). <b>Conclusions</b>: These findings support the potential of liposome-encapsulated <i>Cymbopogon</i> EOs as an effective and sustainable strategy to address AMR. This study provides a foundation for the development of plant-based antimicrobial formulations with improved efficacy.