Efficacy of Mentha pulegium essential oil encapsulated into nanostructured lipid carriers as an in vitro antibacterial and infected wound healing agent

Nanostructured lipid carriers are used for protecting essential oils against environmental factors and also for increasing antimicrobial capability. Gels prepared from Mentha pulegium essential oil (MPO)-loaded into nanostructured lipid carriers (MPO-NLCs) might hasten the infected wound healing process. This study evaluates in-vitro antibacterial activity of MPO-NLCs and in-vivo wound healing activity of MPO-NLCs in BALB/c mice model. To evaluate the effect of MPO-NLCs on wound healing, wound contraction, tissue bacterial count, histological and molecular parameters were assessed at 3, 7 and 14 days after creating wound. MPO-NLCs showed the most antibacterial activity against positive bacteria of Staphylococcus epidermidis, Staphylococcus aureus and Listeria monocytogenes and also negative bacteria of Escherichia coli and Pseudomonas aeruginosa (P < 0.01). Topical administration of MPO-NLCs shortened inflammatory phase and improved proliferative phase. Moreover, administration of MPO-NLCs increased the expressions of IL-10, TGF-β and b-FGF and also decreased the levels of NF-κB compared to the control group (P < 0.05). In sum, the MPO-NLCs promoted infected wound healing by increasing antibacterial properties, decreasing inflammatory phase and accelerating proliferation phase of wound healing process. On the basis of the results, MPO-NLCs can be used an agent for the treatment of the infectious wounds.