Incorporation of Ellagic-Acid-Enriched Lignin into Hydrophilic Electrospun PDLLA/PVP Fibrous Scaffolds Imparts Remarkable Antioxidant and Cellular Redox Protection Properties

A promising strategy to counteract reactive oxygen species (ROS) at cell–material interfaces, a condition that severely compromises cell viability and tissue regeneration, hinges on the incorporation of effective natural antioxidants into biocompatible polymeric scaffolds. Low- and high-molecular-weight phenolic compounds like ellagic acid (EA) and lignin can be easily obtained through green extraction methodologies from wood wastes, such as chestnut wood fiber (CWF), offering biocompatibility and intrinsic redox-protective properties. However, fabricating homogeneous lignin-based biomaterials remains challenging due to the inherent poor solubility properties of lignin. Herein, we report the fabrication of electrospun poly(d,l-lactide)/poly(vinylpyrrolidone) (PDLLA/PVP) mats loaded with an EA-enriched lignin (2% or 4% w/w) extracted from CWF via deep eutectic solvents (DES). The morphological and physicochemical properties of the scaffolds were characterized by scanning electron microscopy, attenuated total reflectance–Fourier transform infrared spectroscopy, and water contact angle. The EA–lignin-enriched mats exhibited remarkable antioxidant capacity, as evaluated by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and cupric reducing antioxidant capacity (CUPRAC) assays, coupled with a sustained and controlled release of EA under physiological conditions. Furthermore, the mats proved highly cytocompatible and capable of significantly mitigating intracellular ROS levels in both normal human dermal fibroblasts and mesenchymal stem cells subjected to oxidative insults. These findings demonstrate that the EA-enriched lignin can be successfully incorporated into electrospun scaffolds, yielding an effective antioxidant biomaterial for biomedical applications.