Abstract
The purpose of this paper is to develop sustainable bio-colored healthcare cotton fabrics using chitosan/pectin layer-by-layer coatings enriched with strawberry pomace extract. Ultrasound-assisted extraction of bioactive compounds from strawberry pomace was optimized using a Box–Behnken experimental design to maximize the total polyphenol content (29.6 mg GAE/g DW). HPLC analysis confirmed the presence and quantity of anthocyanins in the extract obtained under optimized conditions (time: 37 min, ethanol concentration: 48.4%, liquid-to-solid ratio: 40.4 mL/g). This extract was used to enrich chitosan/pectin coatings, and applied onto cotton fabric using a layer-by-layer technique. Among the fabrics with 0, 4, 8, and 12 bilayers of chitosan/pectin coating enriched with extract, the 12-bilayer coated fabric exhibited the best bioactivity: 98.4% antioxidant activity, outstanding antibacterial efficacy, and the highest release of extract over 24 h. The last two properties showed a strong linear correlation with the number of bilayers, adsorbed extract, and weight gain. In vitro cytotoxicity testing proved the non-cytotoxic nature of 12-bilayer fabric extract. Additionally, the performed 12-bilayer coating imparted a natural reddish-brown color, high color strength (K/S = 1.45), and excellent UV protection (UPF 79.4), offering a sustainable, multifunctional approach for obtaining bio-colored cotton fabrics suited for wound dressing and other healthcare applications.