In Situ Adsorption of Red Onion (Allium cepa) Natural Dye on Cellulose Model Films and Fabrics Exploiting Chitosan as a Natural Mordant

Recent development of carrier materials in anthocyanins encapsulation applications: A comprehensive literature review

Anthocyanins are natural polyphenols belonging to the flavonoid family that possess a variety of putative health benefits when consumed in a balanced diet. However, applications of anthocyanins in, for example, functional foods are limited due to poor stability, degradation, and low transmembrane efficiency. To maintain bioactivities of anthocyanins and optimize their use, various carrier materials have been developed. Here, we reviewed the uses of the different carrier materials (organic/inorganic, micro/nano) for anthocyanin encapsulation and delivery over the past five years. The performance of different materials and interactions between anthocyanins and these materials are described. Lastly, we give our perspective on the future development trend of anthocyanin encapsulation strategies.

Bio-mordants: a review

Due to the increasing pressure on environmentally friendly approaches and sustainable production processes, the textile dyeing industry has focused on natural colorants. Thus, the use of bio-mordants, which are biological materials, has become widespread as an alternative to metal salts, most of which are non-ecological, used in the application processes of natural colorants. In natural dyeing, dyers want to use mordant substances in the dyeing processes in order to both expand the color spectrum and improve the fastness properties. Conventional metal salts used in natural dyeing are made up of metallic ions, which, when released into the environment as wastewater effluent at the end of the dyeing process, cause major damage to the ecosystem. Many researchers have thought about using mordants derived from natural sources to address the environmental problem. This article is a review of the investigation of natural mordants used instead of metallic mordants in the process of coloring various textile materials with natural dyestuff sources. It has been determined that many substances, most of them herbal materials, are used as mordants. In this review, mordants, except for conventional metal salts, are examined under three main groups for a better understanding. These groups are as follows: (i) natural or bio-mordants, (ii) oil mordants, and (iii) new-generation and non-vegetable-based mordants. Here, researchers will find an overview of the most recent developments in green mordants as well as application techniques for a variety of mordants.

Phenolic Compounds from By-Products for Functional Textiles

Textile dyeing is known to have major environmental concerns, especially with the high use of toxic chemicals. The use of alternatives such as natural dyes rich in phenolic compounds has become extremely appealing in order to move towards a more sustainable circular economy. Phenolic dyes have the potential to functionalize textile fabrics with properties such as antimicrobial, antioxidant, and UV protection. Wastes/residues from the agri-food industries stand out as highly attractive sources of these compounds, with several by-products showing promising results in textile dyeing through the implementation of more sustainable and eco-friendly processes. This review presents an up-to-date exploration of the sources of phenolic compounds used in the textile industry over the past two decades, with a primary focus on the functional properties they provide to different fabrics. The research highlights a surge in interest in this theme since 2017, accentuating a noticeable upward trend. Throughout this review, emphasis is given to by-products from the agri-food industry as the sources of these compounds. The reviewed papers lay the foundation for future research, paving the way for exploring the potential of raw materials and by-products in the creation of functional and smart textiles.

Enhancing wool dyeing with clove bud (Syzygium aromaticum) based natural dye via microwave treatment using a central composite design

This research investigates the viability of using Syzygium aromaticum (clove) as a natural dye for wool yarn through the application of microwave treatment and optimization using central composite design (CCD). As concerns grow over the environmental impact of synthetic dyes and their detrimental disposal in water bodies, the search for eco-friendly alternatives becomes imperative to revolutionize the textile industry. Microwave-assisted extraction of the colorant from clove powder is explored as an efficient and sustainable method, minimizing solvent usage and energy consumption compared to conventional techniques. To enhance colorfastness properties while eliminating the need for toxic mordants, green alternatives such as Al, Fe, and tannic acid, combined with plant phenolics from red sumac, pomegranate rind, and weld, are employed. According to the analysis of CCD, the higher color strength value 18.1653 was achieved using pH = 3, time = 50 min, temperature = 70 °C, and salt concentration = 1.5 g/100 mL. The optimized dyeing conditions also showed a maximum level of colorfastness properties of 5 for light, 5 for wash, 5 for dry rubbing, and 4 for wet rubbing. The findings from Fourier-transform infrared spectroscopy and scanning electron microscopy analyses provide valuable insights into the chemical and morphological changes induced by microwave treatment and dyeing with clove extract. The results affirm the presence of eugenol as a potential active molecule responsible for the captivating color of clove flower buds, validating its suitability as a natural dye source for wool. This study highlights the promising potential of microwave-assisted extraction and plant-based biomolecules as innovative and environmentally friendly approaches in natural dyeing, paving the way for a more sustainable future in the textile industry. Embracing these eco-friendly practices allows the textile sector to reduce its ecological footprint and contribute to a cleaner and greener environment. Further research and implementation of these techniques can foster a more harmonious coexistence with nature, ensuring a healthier ecosystem for all.

Fabrication of chitosan/phenylboronic acid/SiO2 hydrogel composite silk fabrics for enhanced adsorption and controllable release on luteolin

Due to the growing demand for self-health and safety, eco-friendly health textile products with natural colors and pharmacological functionalities have gained considerable popularity. Rapid adsorption and controlled release of active molecules are important issues for functional health textiles. In this study, a functionalized chitosan-based hydrogel composite silk fabric was prepared using chitosan, 3-carboxyphenylboronic acid, and 3-(2, 3-epoxypropyl oxygen) propyl silane by dip-pad and vacuum freeze-drying techniques. The results showed that the incorporation of chitosan/phenylboronic/SiO2 hydrogel into silk fibers improved the UV protection capacity, mechanical properties, and adsorption properties of silk fabrics. The effects of various parameters on the luteolin adsorption properties of silk fabrics were discussed, including metal salt types, salt dosage, pH value, dyeing temperature, initial luteolin concentration, and dyeing time. Under the dyeing temperature of 60 °C and pH of 6.8, the luteolin exhaustion of the composite silk was more than that of the untreated silk, and the adsorption process followed the quasi-second-order kinetic model and the Langmuir adsorption isotherm model. Furthermore, the luteolin-dyed composite silk materials exhibited strong antioxidant activity and controllable release behavior with various pH levels. The as-prepared chitosan-hydrogel composite silk could be a promising material for the sustained release of drugs in medical and healthcare textiles.