Antimicrobial and wound healing properties of cotton fabrics functionalized with oil-in-water emulsions containing Pinus brutia bark extract and Pycnogenol® for biomedical applications.

Topical formulations containing 1-2% of Pinus brutia bark extract and Pycnogenol® have been prepared to investigate the effect of flavonoids on the stability of O/W emulsions, which were subjected to physicochemical and thermal stability tests. The formulations have been applied to cotton fabrics to evaluate antimicrobial properties against Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus brasiliensis. Furthermore, prepared cotton fabrics have been tested on keratinocytes seeded in cell culture inserts for wound healing. Results of freeze thaw cycle test indicated enhanced thermo-stability with no major changes in pH and viscosity, likewise the results of centrifugation assay. However, the addition of Pycnogenol® has tremendously decreased the viscosity of the topical formulation (10,900 cp.). In terms of antimicrobial activity, 2% P. brutia treated cotton fabrics decreased the proliferation of Aspergillus brasiliensis 78.8%, which were more effective than that of Pycnogenol® formulation (62.9%). As for wound healing, 2% P. brutia treated cotton fabrics increased HaCaT keratinocyte cell proliferation and accelerated the cell-free gap closure compared to Pycnogenol® and untreated control groups. The obtained results indicate the utilization of pine bark for developing an eco-friendly natural antifungal finish for medical textiles.