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(a) Color depth expressed as K/S at minimum reflectance values, reflectance at 480 and 520 nm of the ROD-dyed cotton fabrics demonstrating the efficiency of chitosan and FeSO 4 as mordants; the higher the value, the stronger the color. (b) Color change after washing (ΔE) between the untreated and washed fabric in two pH conditions; the lower the value, the least change of color in washing.
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Synthetic dyes and chemicals create an enormous impact on environmental pollution both in textile manufacturing and after the product's lifetime. Biobased plant-derived colorants and mordants have great potential for the development of more sustainable textile dyeing processes. Colorants isolated from biomass residues are renewable, biodegradable,...
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... CNFs prepared from the same pulp and using a similar procedure as used here have been reported to carry a low negative charge. 46,47 Furthermore, preliminary results showed that ROD was slightly better absorbed to CNF model films at pH 4 ( Figure S5), and previous studies also supported a mildly acidic environment as an optimal condition for dyeing using plant-extracted natural dyes. 48−51 ROD adsorption onto CNF thin films (Figure 3c) was performed stepwise. ...
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... textile applications, color depth is typically expressed as a ratio of absorption and scattering coefficients, also known as K/S values. Figure 5a depicts the K/S values for dyed cotton fabrics dyed with ROD and mordants chitosan, iron(II), and aluminum(III) at pH 4 optimum conditions and the color change values (ΔE) after washing tests at pH 7 and 10. ...
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... color difference after washing (ΔE) (Figure 5b) reveals that the ability of chitosan to stabilize the color when subjected to alkaline laundering pHs is lower than for the metal ions, especially around neutral conditions. The greatest ΔE values were observed after washing at pH 10 due to the phenolic OHgroups of the natural dye that ionize, causing a bathochromic shift to the absorption spectrum and a visible change of the observed color from red to green. ...
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... color fastness values for washing and rubbing were similar to metal mordanted samples revealing that chitosan increases the adsorption of the dye onto the fiber and, thus, produces compatible results with metal mordants. However, the challenge remains in stabilizing the color chromophore, which is sensitive to light and pH changes ( Figure S5c). The iron ion stabilizes the chromophore and color resulting in slightly higher values in color fastness tests and especially increases light fastness stability (Table S4), generally taken at moderate levels. ...
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... procedure ( Figure S1); experimental setup (Table S1); 1 and 2D NMR spectra of ROD ( Figure S2); NMR spectra of pectin ( Figure S3); mass balance of HWE (Table S2); chemical characterization of pectin (Table S3); FTIR spectra of ROD and dyed fabrics ( Figure S4); change in oscillation frequencies in ROD in different pH, maximum sensed masses, and visual appearances of ROD in varying pH and on standing ( Figure S5); and CIE L*, a*, b* color coordinates and visual color, K/S values, washing fastness, and rubbing fastness of the dyed cotton fabrics (Table S4) ...
Citations
... Additionally, the presence of cyanidin is indicated by the shoulder peak observed at 530 nm in the green region. This peak is associated with the chromophoric part of the anthocyanin [21]. The distinctive peaks of CT anthocyanin, centered at 576 and 622 nm in the yellow and orange regions, respectively, can be ascribed to the S 0 → S 1 and S 0 → S 2 electronic transitions within the flavylium cation [22], [23], [24]. ...
In the food industry, confusion stemming from expiration and date labels contributes to unnecessary food waste, underscoring the growing need for innovative food freshness sensors. This study presents a novel, cost-effective, and environmentally friendly dual-mode ammonia sensor tailored for real-time quality monitoring of protein-rich food products. Utilizing naturally occurring anthocyanin extracted from Clitoria ternatea and reinforced with polyvinyl alcohol (PVA) in a paper-based colorimetric system, the sensor demonstrates heightened sensitivity to ammonia gas, a key indicator of spoilage in protein-rich foods. Integration of a graphene nanoplatelets layer enables additional resistive gas sensing capabilities. The practicality and versatility of the fabricated sensor are enhanced by integrating near-field communication (NFC) technology, which facilitates batteryless and wireless sensing response transmission. The fabrication process of the sensor involves a straightforward, low-temperature solution route utilizing dip-coating and brush-coating methods. The incorporation of PVA significantly amplifies the colorimetric response, evidenced by a 44% increase in total color change compared to non-PVA reinforced sensor. This augmentation results in a more pronounced color change, which is readily discernible to the naked eye. The developed dual-mode sensor, equipped with NFC, is successfully applied to monitor shrimp freshness, demonstrating distinct color changes and NFC tag readability in response to ammonia release during spoilage. With its attributes of cost-effectiveness, environmental friendliness, simplicity, and wireless capabilities, this sensor offers a promising solution for widespread adoption in the food industry. This work contributes to advancing sensor technology, providing a versatile tool to ensure the quality and safety of perishable goods.
... 17 Cellulosic fibers (cotton and flax, etc.) dyed with natural plant-derived dyestuff are the subject of a lot of work. [18][19][20][21] Because naturally generated plant fibers are abundant in our natural surroundings and have excellent environmental sustainability and renewability features, these materials are gaining a lot of interest. 22,23 Synthetic dyes disturb the environment and are not entirely biodegradable. ...
The development of more sustainable textile dyeing techniques includes a lot of potential in utilizing bio-based plant-derived colorants. Hemp fabric has been dyed with an aqueous extract of pine cones at various dye concentrations to produce a brownish to darker color. Agricultural waste specimens, Anatolian black pine ( Pinus nigra subsp. Pallassiana), and Scots pine ( Pinus sylvestris L.) cones were used as natural dye sources on a sustainable basis. The dyed hemp fabrics were analyzed by different analytical and technical methods such as CIE L*a*b*, high-pressure liquid chromatography–diode-array detection, and scanning electron microscopy with an energy dispersive X-ray spectrometer. The color characteristics of all the dyed fabrics were measured by a CIE L*a*b* spectrophotometer. The reversed-phase high-pressure liquid chromatography–diode-array detection method with the diode-array detection method was utilized for the identification of the components of dyes present in the dyed fabrics. Scanning electron microscopy with an energy dispersive X-ray spectrometer was used for imaging and elemental analysis of the surfaces of the dyed hemp fabrics. This work has created a novelty direct dyeing method with pine cones without using any mordants and to promote the use of agricultural waste. The fastness values of washing, rubbing, and light were assessed and contrasted. The fastness results were good in general. Washing fastness values were excellent and the same for all fabrics between 4 and 5. Rubbing fastness is also generally good and of the desired grade. The chemical compositions of hemp and pine cones, as well as the formation of dyestuff fiber, were investigated by using Fourier transform infrared analysis.
... Chitosan is a natural biomordant that has been shown to be effective in dyeing cotton fabrics with natural dyes. However, there is a lack of research on the use of chitosan to dye cotton fabrics with pomegranate rind and onion peel using a one-bath dyeing process (Grande et al. 2023;Haji 2017;Jeyakodi Moses and Venkataraman 2016;Silva et al. 2018;Verma et al. 2021). ...
... However, a strong binding may take place when chitosan is used as the mordant. Chitosan is a renewable polymer with positively charged groups, where ionic interactions may also take place binding the dye (Fang et al. 2023;Grande et al. 2023). Noticeably, the PR-CS dyed fabric showed a higher washing fastness than the OP-CS dyed fabric. ...
A sustainable one-bath dyeing and functionalization process of cotton fabrics with pomegranate rind and onion peel extract using chitosan (CS) biomordant was investigated. Liquid chromatography-mass spectrometry was used to verify the presence of the main colorants, ellagic acid and quercetin, in the prepared extracts of pomegranate rind and onion peel. CS mordanting improved the color strength and wash fastness of pomegranate rind and onion peel dyed fabric by up to 36% and half a rating point, respectively. CS significantly enhanced the UV protection (UPF 50+) and antimicrobial activity (ranges from 93.8 to 99.9%) of dyed fabric. Chitosan mordanting improved the bending rigidity and compression recovery of the cotton fabric, but it also reduced the handle and flexibility of the treated fabrics owing to the formation of CS layer on the cotton fabrics. The dyed fabric also showed remarkable deodorizing (above 80%) and antioxidant (above 90%) properties. Overall, the proposed process could be a sustainable and economical alternative to the conventional metal mordant process.
... 10 The versatility of bio-based colorants extends beyond textile dyeing, as they find applications in food coloring, leather tanning, and dyeing of natural fibers. 11 This broadens their potential usage, promoting sustainable practices in various industries beyond textiles. The adoption of natural colorants in these diverse fields aligns with the growing demand for environmentally friendly and non-toxic alternatives, fostering a safer and ecologically conscious approach to manufacturing processes. ...
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.
... Skins from almonds can represent up to 8% of a total shelled almond weight [17]. The production of onion, the second most abundant horticultural crop in the world, generates half a million tons of biowaste (skins) in Europe alone [102]. In some extreme cases, such as in the R. luteola plant, about 300 g of by-products (stems, roots, and grains) are discarded in order to harvest just 1 g of leaves [47]. ...
... Different studies show that agri-food by-products and wastes provide adequate streams for the valorization of natural dyes, especially when applied on a niche scale [102]. Additionally, these studies have established a groundwork for future investigations where these and other raw materials and by-products rich in polyphenols could be researched and scaled up to be implemented at an industrial level for the production of functional and smart 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.
... For some anthocyanin-rich biomass or plant extracts, as carrier materials, chitosan combined with sodium alginate (Kanokpanont et al., 2018;, gelatin (Atay et al., 2018), tripolyphosphate (Laila et al., 2019), a combination of gum arabic (Martins et al., 2020), cellulose (Grande et al., 2023), or chondroitin sulfate could also improve the applicability of anthocyanins. ...
... Allium cepa L. (Family Amaryllidaceae) ( Bellakhdar, 1997) Oignon ( Bellakhdar, 1997) Bulb onion ( Bellakhdar, 1997) Besla ( Bellakhdar, 1997) Wool and silk (Saxena et al., 2014) Cotton ( Grande et al., 2023;Botteri et al., 2022) Antidiabetics, antibiotics, cholesterollowering agents, fibrinolytics ( Augusti, 1996) Cultivated A total cultivated area: 5.15 Mha An annual production: 99.5 Mt ( FAOSTAT. FAO Statistics, 2023) 6. ...
... Allium cepa L. or onion is a perennial plant of 20-50 cm (Fig. 10), glabrous, with ovoid-oblong bulbs, growing in clumps with a hollow stem, little or not bulging, leafy at the base and persistent, cylindrical, and hollow leaves. The peel of the onion has long been used to extract yellow dyes (Saxena et al., 2014;Grande et al., 2023). Allium cepa L. belongs to the family Amaryllidaceae and the genus Allium. ...
Ethnobotanical study aimed at investigating the diversity and importance of Moroccan tinctorial plants used for dyeing of natural fibres and medicinal purposes. The study has conducted an extensive survey over three months in Marrakech city in south-central Morocco in order to outline the most used natural dyes and to assess their availability in the region. As the result, forty Moroccan tinctorial plants were inventoried, among them, fourteen indigenous plants were identified as widely traded for artisanal or medicinal use throughout the country. Complemented by the previous survey and studies of Moroccan flora, important information was harvested for the inventoried plants such as botanical and vernacular names, geographical origin, minimum abundance, color, parts used, chemical composition, dye classification, applications, purchase cost and rate of use for each plant.
Using phytochemical screening for the extracted dyes from these plants, major chromophores were identified, namely flavonoids, anthraquinones, naphthoquinones, alkaloids, carotenoids, polyphenols (tannins), and indigoids. These chromophores were served as the basis for the classification of dye extracts, which revealed two main types of tinctorial plants, with high and low dyeing properties. For each class of extracted dyes, the specific dyeing process was described to obtain the best dye application.
Besides providing colour, the present dyes, as the vast majority of natural dyes, have inherent functional properties such as resistance for bacteria, fungus and moth. Specifically, dyes extracted from Reseda luteola L., Eucalyptus globulus, Punica granatum L., and Juglans regia L. exhibite high resistance towards Escherichia.coli, Staphylococcus aureus and Pseudomonas aeruginosa bacteria. Nevertheless, the use of natural dyes can also have harmful effects. Some toxic mordants should to be used carefully and others have to be avoided due to their high toxicity for the human body and environment.
In addition, the composition of the plant biomass was assessed with a view to possible waste reuse. The results provide valuable information for the exploitation, recycling, and industrialization of natural dyes, as well as for scientific research in this field.
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.
