{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T03:01:07Z","timestamp":1790650867211,"version":"4.1.0"},"reference-count":45,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T00:00:00Z","timestamp":1776988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study examined how the extraction medium used to obtain Quercus robur extracts influenced the properties of electrospun poly(vinyl alcohol) (PVA) mats intended for potential active packaging applications. Extracts prepared with 50% ethanol and with a choline chloride:lactic acid:water system were incorporated into PVA spinning solutions, and their effects on solution properties, fiber morphology, thermal behavior, crosslinking response, and polyphenol release were evaluated. The type of extraction medium affected both the electrospinning process and the structure of the resulting materials. Ethanol-derived extracts reduced solution viscosity and promoted the formation of thinner fibers, whereas systems containing the choline chloride:lactic acid:water-derived extract showed higher conductivity and lower electrospinning stability. Crosslinking with tannic acid in water led to the collapse of the fibrous structure, while ethanolic tannic acid treatment preserved the nanofibrous morphology more effectively. FTIR analysis indicated differences in intermolecular interactions within the polymer matrix, consistent with the observed changes in structural stability and release behavior. Thermal analysis showed that ethanol-derived extracts lowered the thermal stability of the PVA matrix, whereas the choline chloride:lactic acid:water-derived system altered the degradation pathway and increased the amount of solid residue formed during heating. Release studies demonstrated a rapid burst release for ethanol-based mats and a more sustained release profile for mats containing the choline chloride:lactic acid:water-derived extract. Selected extract-containing and ethanol\u2013tannic acid-crosslinked mats also showed antibacterial activity against Staphylococcus aureus. The results showed that the extraction medium significantly affected polymer\u2013extract interactions and the functional properties of electrospun PVA mats. At the same time, the conclusions refer specifically to the tested solvent systems, and broader generalization to other natural deep eutectic solvent-type formulations requires further comparative studies.<\/jats:p>","DOI":"10.3390\/ma19091730","type":"journal-article","created":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T12:29:11Z","timestamp":1777033751000},"page":"1730","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Effect of the Extraction Medium (A Natural Deep Eutectic Solvent-Derived System vs. Ethanol) on the Properties of Electrospun PVA Fibers Containing Quercus robur Extracts"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-3542-7241","authenticated-orcid":false,"given":"Julia","family":"Wn\u0119kowicz","sequence":"first","affiliation":[{"name":"Faculty of Chemistry, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Szopa","sequence":"additional","affiliation":[{"name":"Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wroc\u0142aw University of Science and Technology, Gda\u0144ska 7\/9, 50-344 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paulina","family":"Wr\u00f3bel","sequence":"additional","affiliation":[{"name":"Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wroc\u0142aw University of Science and Technology, Gda\u0144ska 7\/9, 50-344 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-9258-4044","authenticated-orcid":false,"given":"Julia","family":"Zwoli\u0144ska","sequence":"additional","affiliation":[{"name":"Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wroc\u0142aw University of Science and Technology, Gda\u0144ska 7\/9, 50-344 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8632-385X","authenticated-orcid":false,"given":"Maciej","family":"Kaniewski","sequence":"additional","affiliation":[{"name":"Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wroc\u0142aw University of Science and Technology, Gda\u0144ska 7\/9, 50-344 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacek","family":"Ch\u0119cmanowski","sequence":"additional","affiliation":[{"name":"Department of Advanced Material Technologies, Faculty of Chemistry, Wroclaw University of Science and Technology, Smoluchowskiego 25, 50-370 Wroclaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5706-0133","authenticated-orcid":false,"given":"Anna","family":"Witek-Krowiak","sequence":"additional","affiliation":[{"name":"Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wroc\u0142aw University of Science and Technology, Gda\u0144ska 7\/9, 50-344 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1002\/pts.2863","article-title":"Active Packaging System\u2014An Overview of Recent Advances for Enhanced Food Quality and Safety","volume":"38","author":"Kadirvel","year":"2025","journal-title":"Packag. 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