Evaluation of the Antibacterial Properties of Polyvinyl Alcohol-Pullulan Scaffolds Loaded with Nepeta racemosa Lam. Essential Oil and Perspectives for Possible Applications

Essential oil of Nepeta racemosa Lam. was extracted and characterized to determine its antimicrobial activity and potential use in applications. The essential oil was loaded on polyvinyl alcohol-pullulan films and gels and characterized by optical microscopy, scanning electron microscopy, and UV-Vis spectroscopy before having its antimicrobial capacities assessed. The essential oil extracted from Nepeta racemosa Lam. was characterized using gas chromatography coupled with mass spectroscopy, which indicated that the most abundant component was nepetalic acid (55.5%), followed by eucalyptol (10.7%) and other compounds with concentrations of about 5% or less. The essential oil, as well as the loaded films and gels, exhibited good antibacterial activity on both gram-positive and gram-negative strains, with growth inhibition zones larger in some cases than for gentamicin, indicating excellent premises for using these essential-oil-loaded materials for applications in the food industry or biomedicine.

Automated summary

The essential oil of Nepeta racemosa Lam. was extracted and characterized for its antimicrobial activity and potential applications. Gas chromatography coupled with mass spectroscopy revealed that the most abundant component in the essential oil was nepetalic acid (55.5%), followed by eucalyptol (10.7%) and other compounds at concentrations of about 5% or less. The essential oil, as well as the films and gels loaded with it, exhibited strong antibacterial activity against both gram-positive and gram-negative strains, suggesting their potential use in the food industry or biomedicine.