Phytochemical finishing of cotton fabrics using Bambusa arundinacea, Terminalia arjuna, and Jatropha curcas extracts: Spectroscopic characterization and color fastness assessment

The booming demand for eco-friendly and bioactive textile solutions has increased interest in plant-derived phytochemicals for fabric improvement. Bambusa arundinacea, Terminalia arjuna, and Jatropha curcas are renowned for their rich phytochemical profiles, offering possibilities for sustainable dyeing, antimicrobial properties, and UV protection in fabrics. Developing durable and eco-friendly textile finishes with plant extracts is challenging due to weak binding, inconsistent fastness, and photostability issues. Methanolic extracts of B. arundinacea leaves, T. arjuna bark, J. curcas roots, along with a 90:10 blend of the first two, were applied to cotton fabrics using alum as a natural mordant. Fourier-transform infrared spectroscopy was conducted on both extracts and treated fabrics to examine functional group interactions and surface modifications. Standard colorfastness tests, like rubbing, washing, and light exposure, were performed to assess the permanence and photostability of the applied solutions. FTIR spectra of the extracts revealed key functional groups, including hydroxyl (-OH), carbonyl (C=O), aliphatic (C-H), and aromatic compounds associated with polyphenols, flavonoids, tannins, and fatty acids. These groups were efficiently transferred onto cotton surfaces, as verified by distinct spectral shifts in treated fabrics. The report detailed how alum mordant boosts chemical bonding and surface adherence. Rubbing fastness scores ranged from fair to good dry and poor to fair wet, while clean fastness displayed moderate to strong performance. Light fastness was significantly improved, with 90% extract and 10% blend-treated fabrics achieving a blue wool scale rating of ‘very good’, compared to ‘good’ in the control. The analysis verifies that B. arundinacea and T. arjuna include complementary bioactive mixtures that synergistically enhance textile surface functionality. The enhanced retention of phytochemicals on cloth surfaces was attributed to powerful intermolecular interactions and mordant-aided securing. Fabrics treated with J. curcas exhibited abundant deposits of fatty acids and quinones, pointing to substantial surface alteration. The superior light fastness likely stems from UV-absorbing nature of the polyphenolic compounds, boosting the photostability of dyed textiles. This work demonstrates that methanolic plant extracts, particularly the blend of B. arundinacea and T. arjuna, can be effectively utilized for eco-friendly functional finishing of cotton fabrics. This study demonstrates that methanolic extracts, particularly those of B. arundinacea–T. arjuna blend, overcome these limits by enhancing bonding, light fastness, and sustainable finishing. FTIR analysis provided strong evidence of chemical deposition and interaction, while shade fastness tests confirmed the permanence of the remedies. The findings highlight the potential to develop natural, sustainable, and high-performance textile coatings utilizing phytochemical-rich botanical sources.