Electrospun Nanofibers Loaded with Verbena officinalis Extract as Multifunctional Bioactive Wound Dressings

Abstract

Background/Objectives: Verbena officinalis has long been used in traditional medicine for treating skin disorders, yet its potential in advanced wound-dressing systems remains insufficiently explored. This study aimed to characterize V. officinalis extracts obtained using different solvents, evaluate their antimicrobial, antibiofilm, cytotoxic, and wound-healing activities, and develop electrospun polycaprolactone–polyethylene glycol (PCL–PEG) nanofibers as a delivery platform for the most active extract. Methods: Extracts were chemically characterized by LC–MS and evaluated against clinical bacterial, yeast, and dermatophyte isolates associated with skin infections. Antibiofilm activity was assessed against Staphylococcus lugdunensis. The most active hydroalcoholic extract (EW7.5) was incorporated into PCL–PEG nanofibers (1–10%, w/w). Metabolite release was monitored by semi-quantitative LC–MS analysis. Cytotoxicity and wound-healing activity were evaluated using HaCaT keratinocytes, while in vivo efficacy was assessed in a full-thickness excisional wound model in Dark Agouti rats (five animals per group in two independent experiments). Results: EW7.5 exhibited the strongest antimicrobial activity, with MIC values of 0.06 mg/mL against all tested bacterial and Candida strains and 0.06–0.5 mg/mL against dermatophytes. It inhibited S. lugdunensis biofilm formation by 79.43% at MIC/4 and reduced pre-formed biofilm biomass by 64.98% at 2 × MBC. EW7.5 and EW7.5-loaded nanofibers showed no cytotoxicity up to 400 μg/mL. In the scratch assay, the free extract achieved 42.34 ± 1.58% wound closure, while nanofibers containing 10% EW7.5 achieved 25.87 ± 2.52%, compared to 7.73 ± 0.07% for the control. In vivo, EW7.5-loaded membranes significantly accelerated wound closure and the 10% formulation significantly improved extracellular matrix deposition and vascular remodeling compared to the control membrane. Conclusions: EW7.5-loaded PCL–PEG nanofibers combine antimicrobial, antibiofilm, biocompatible, and wound-healing properties, supporting their potential as multifunctional wound dressings. Nevertheless, further studies with mechanistic investigations are required to fully establish their therapeutic applicability.