Ficus religiosa bark as sustainable dye with antibacterial and UV protective functions for protein-based textiles

The present study explores the sustainable utilisation of Ficus religiosa bark extract as a natural dye and functional finishing agent for protein-based textiles—wool, silk, soya, and milk.Extraction variables, i.e. MLR, pH, temperature and time, are optimised to maximise phenolic, flavonoid, tannin and antioxidant contents. The extract is applied using various mordanting techniques with both chemical and natural mordants, and dyeing conditions are optimised through a Box–Behnken response surface design. The dyed fabrics exhibit a rich spectrum of brown hues with good colour fastness. In addition, they demonstrate improved ultraviolet protection and notable antibacterial activity. The dyed fabrics also exhibit improvement in ultraviolet protection. The findings position F. religiosa bark extract as a sustainable and potential source of economical and ecological dyeing agent for antioxidant, UV protection and antibacterial finishing properties in textiles.