Alginate Micro-fibers encapsulated with oregano essential oil with improved antibacterial efficacy

Functional biopolymers are being extensively studied for applications in various industries to replace synthetic polymers due to their natural origin and biodegradability. Study investigates, alginate natural oregano essential oil (OEO) fibres at varied concentrations using wet-spinning process. The incorporation of oregano essential oil significantly influenced fibre morphology, with fibre diameter decreasing from 139.57 ± 6.81 µm in the control fibres to 108.43 ± 2.77 µm at 2 wt% OEO (p < 0.0001). The produced fibres exhibited good uniformity across all formulations, as indicated by their low diameter variability. FTIR peaks and TGA data reveal the presence of OEO with alginate. Mechanical tests revealed that with the addition of OEO, tensile strength and Young's modulus of the alginate fibres significantly increased from 69 MPa and 3.3 GPa to 97 MPa and 6.3 GPa, respectively, at 3 wt% OEO loading. The functional wet spun alginate-OEO fibres exhibit antimicrobial properties, with the largest inhibition zones methicillin-resistant Staphylococcus aureus and Listeria monocytogenes, with smaller effects against Salmonella typhimurium and Klebsiella pneumoniae at 2 wt% OEO. This method provides a simple, manufacturing platform to incorporate OEO into alginate while retaining the mechanical and antibacterial properties of the alginate fibres. Our study suggests that the OEO-loaded alginate fibres is suitable for antimicrobial application.