Evaluation of patchouli oil in the development of antibacterial nanoemulsion and nanoemulgel for periodontitis: an in vitro study

Periodontitis is a chronic inflammatory disease driven by oral microbial dysbiosis, with <i>Porphyromonas gingivalis</i> playing as pathogenic roles and <i>Fusobacterium nucleatum</i> as a gram-negative bacterium is very relevant in the initiation and development of periodontal disease. Although local antibiotic therapy can help restore oral homeostasis, its effectiveness is often limited by bacterial resistance and poor accessibility to deep periodontal pockets. These limitations underscore the need for alternative therapies with proven antibacterial activity and biocompatibility. In this context, patchouli oil, derived from <i>Pogostemon cablin Benth</i>., offers promising antifungal, anti-inflammatory, and antibacterial properties. This study investigates the antibacterial potential of patchouli oil and its fractions, including crude, light and heavy, formulated into nanoemulsions and nanoemulgels for the adjuvant therapy of periodontitis. To achieve this, the formulation process begins by identifying which fraction meets the criteria for antibacterial efficacy. Antimicrobial characteristics are evaluated through phytochemical profiling, Fourier-transform infrared spectroscopy, and gas chromatography-mass spectrometry. The development of nanoemulsions and nanoemulgels is guided by nanomaterial formulation parameters, including physical characterization to ensure suitability for application as a mouthwash or topical paste aimed at restoring oral homeostasis. The results indicate that crude patchouli oil is a promising candidate for formulation, capable of being incorporated into nanoemulsions and nanoemulgels using surfactants and cosurfactants with appropriate hydrophilic-lipophilic balance. Furthermore, the concentration of the gelling agent significantly influences viscosity, which in turn affects the product's spreadability and retention in the oral cavity.