Curcuma longa L. as a Natural Photoprotective and Antimicrobial Agent in Colored Cotton Textiles (BRS Rubi) from the State of Paraíba

Abstract Currently, there is a growing interest in the development of functionalized textile materials that exhibit new and diverse properties. To this end, turmeric extracts at 10 and 20% (w/v) were impregnated into colored cotton textiles (CCT) from Paraíba/Brazil (BRS Rubi cultivar), to assess the potential of curcumin as a natural photoprotective and antimicrobial dye for use in everyday clothing. Ultraviolet–Visible (UV–Vis) spectra revealed the majority presence of curcumin as the main bioactive of interest in this study. From optical microscopy, it was possible to observe the interwoven structure of the weave and a uniform distribution of the extracts, demonstrating good fixation to the cotton textile fibers. UV–Vis spectrometry enabled the calculation of the ultraviolet protection factor (UPF). For Untreated CCT, a UPF of 25 (medium protection) was observed, while for Treated CCT it was 22 (adequate protection). On the other hand, the textiles impregnated with the extracts (CCT+ExC10% and 20%) showed a significant increase, with UPF values from 34 and 38, respectively, both classified as medium UV protection. In addition, textiles showed a broad spectrum of microbial reduction, especially for CCT+ExC20% which demonstrated the highest values of antimicrobial activity against S. aureus , P. aeruginosa and C. albicans when compared to the other samples. These results demonstrate the potential of curcumin as a promising natural antimicrobial and photoprotective agent. This environmentally friendly approach addresses both health and environmental concerns, offering a viable alternative to synthetic antibacterial and UV protection agents in the textile industry.