Propolis loading governs the morphology, stability, and wound-relevant bioactivity of electrospun PVA/gelatin nanofiber membranes

Electrospun poly(vinyl alcohol)/gelatin (PVA/gelatin) nanofiber membranes containing 0–2.0% (v/v) propolis were fabricated to investigate how propolis loading governs membrane morphology, stability, and wound-relevant bioactivity. Increasing propolis concentration increased the mean fiber diameter from 170 ± 75 to 596 ± 453 nm and promoted partial fiber fusion at higher loadings. FTIR confirmed propolis incorporation, while DSC and TGA showed concentration-dependent changes in thermal behavior; T 50 increased from 349.78 °C for the propolis-free membrane to 427.12–446.70 °C after propolis incorporation. Propolis also altered aqueous behavior, with intermediate loadings showing markedly lower degradability. Lower to moderate propolis loading supported higher fibroblast viability, whereas higher loading generally enhanced cell migration and DPPH/ABTS radical-scavenging activity. Propolis-containing membranes reduced LPS-induced nitrite production in RAW 264.7 macrophages, although the response was formulation-dependent. Qualitative disc-diffusion screening showed detectable inhibition against Staphylococcus aureus from PG05P onward and against Pseudomonas aeruginosa at PG15P and PG20P. PG10P provided a favorable balance among morphology, aqueous stability, thermal stability, and measured biological responses. These findings provide an initial structure–stability–bioactivity framework, while mechanical suitability, propolis release kinetics, and quantitative antimicrobial potency remain to be established.