Peroxidase-Catalyzed Coloration for Fabric Design with Color Patterns

Biological environmentally friendly concepts are emerging to replace chemical treatments of fabrics. In this work, a new process for the coloration of flax fabrics via enzymatic oxidation of natural flavonoids (morin, quercetin) has been developed. Laccase fromTrametes hirsutais able to react with flavonoids and polymerize them, resulting in a strongly colored polymeric solution which can be applied to the coloration of flax fabrics. Two methods were investigated:(i)the simultaneous enzymatic polymerization and coloration of fabrics and(ii)the polymerization of flavonoids with laccase, followed by a further coloration of the flax fabrics. Factors such as temperature, reaction time, presence of NaCl or the use of bleached or unbleached fabrics were evaluated in order to increase the color of the fabrics and the color fastness. The increase of temperature, the presence of salt and the use of unbleached fabrics allowed the final color to be improved. Colorized flax fabrics with oxidized quercetin solution showed a color fixation two times higher than the fabrics colorized with oxidized morin. Finally, the polymerization of flavonoids and their binding to fibers were verified using Fourier transform infrared spectroscopy (FT‐IR). The results confirmed this environmentally friendly process as useful for the coloration of flax fabrics. A similar technique could also be extended to the treatment of other types of fabrics in textile processes.

The search for a more ecological alternative to dyeing processes, which is the most polluting textile process, has become one of the most studied topics today. In this respect, enzymatic colouring with the use of laccases offer important opportunities, but studies on enzymatic colouring are still very limited. However, in order for enzymatic dyeing to find industrial‐scale use, the colour variety must be wide. Within the scope of this study, it is an important output that this study has brought to the literature, that the variety of colours that have been obtained in the literature in enzymatic dyeing has been increased so far by working with a wide variety of precursors and their mixtures, including those that have not been tested on wool before. At the same time, the reaction mechanism of the enzymatic dye synthesis and the chemical structures of the dyes were elucidated by Fourier‐transform infrared spectroscopy. Beyond that, as it is known, when a new dyeing process is developed, its technical, economic and ecological advantages and disadvantages compared to the currently accepted conventional dyeing should be revealed. In this study, the colours obtained by enzymatic dyeing were matched with 1:2 metal complex dyes and then two fabrics dyed with the same colour, one enzymatic and the other with conventional method, were compared in terms of technical (colour, fastness), economic (water, energy and chemical consumption) and ecological (biological oxygen demand of wastewater, chemical oxygen demand, etc.) aspects.

Among the textile wet processes, the colouring process is the process step that causes the most environmental pollution. New approaches that support sustainable production instead of environmentally harmful processes are extensively researched in the literature. When considering substitution of chemical processes with environmentally friendly methods, one of the issues that comes to mind is enzymatic processes. It is noteworthy that in recent years, interesting and promising studies on the use of laccase enzymes in textile dyeing have been published in the literature. However, studies on enzymatic colouring are still very limited and sufficient success has not been achieved especially on polyamide. The aim of this study is to develop an environmentally friendly enzymatic dyeing method, which can be an alternative to dyeing polyamide knitted fabrics with 1:2 metal complex dyes according to the exhaustion method. For this purpose, various phenol and amine compounds, and their mixtures were used as precursor, and the colours that can be obtained by enzymatic colouring have been determined. In addition, optimisation of enzymatic colouring conditions (enzyme concentration, temperature and time) was carried out for the precursors that gave the best results in terms of colour and fastness. Furthermore, enzymatic dyeing was compared with conventional 1:2 metal complex dyeing in terms of technical and economic aspects. The reaction pathways in enzymatic coloration with laccase enzyme by using various precursors were also explained by Fourier‐transform infrared (FTIR) analysis.

In this study, dyeing properties of cotton fabrics with red cabbage extract as a natural colorant and by mordanting materials like potassium aluminumsulphate and tannic acid were investigated. Pre-mordanting, simultaneous mordanting and post-mordanting methods were used for mordanting of cotton fabric and natural dyeing process was carried out by exhaustion method. Moreover, since it is known that red cabbage presents different colors in different pH values due to its indicator property, the trials were renewed for three pH conditions as acidic, basic and neutral. After dyeing processes, color measurement, washing and rubbing fastness tests were applied to the samples. As a result of the study, it was observed that red cabbage extract can be used to dye cotton fabrics and the most permanent colors can be obtained in neutral pH conditions. When mordanting methods and mordanting materials were compared to each other, it was determined that various color shades were provided according to the mordanting materials and methods. In terms of general, it was concluded that uniform dyeings with high color yield can be obtained by tannic acid mordant and pre-mordanting method and high mordant concentration should be used to get dark color shades. In addition, washing and rubbing fastness values were determined to be in acceptable limits for natural dyeing.

The textile industry, a substantial component of the global economy, holds significant importance due to its environmental impacts. Particularly, the use of water and chemicals during dyeing processes raises concerns in the context of climate change and environmental sustainability. Hence, it is crucial from both environmental and economic standpoints for textile factories to adopt green industry standards, particularly in their dyeing operations. Adapting to the green industry aims to reduce water and energy consumption in textile dyeing processes, minimize waste, and decrease the carbon footprint. This approach has become crucial in achieving sustainability in textiles following the signing of the Paris Climate Agreement. Important elements of this transformation include the reuse of washing waters used in the dyeing process, the recycling of wastewater, and the enhancement of energy efficiency through necessary methodological and equipment changes. This study analyzes the energy, labor, production, and consumption data since 2011 for a textile factories with four branches located in the Adana Organized Industrial Zone. Among these factories, the one designated as UT1, which has the highest average energy and water consumption compared to the other three branches, is selected. In recent years, the use of artificial intelligence and machine learning technologies in predicting industrial processes has been increasingly observed. The data are analyzed using LSTM (Long Short-Term Memory) and ANN (Artificial Neural Networks) forecasting methods. Particularly, the LSTM algorithms, which provided the most accurate results, have enabled advanced forecasting of electricity consumption in dyeing processes for future years. In 2020, electricity consumption was recorded as 3,717,224 kWh and this consumption was reflected in the total energy cost as TRY 1,916,032. Electricity consumption accounts for 22.34% of total energy consumption, while the share of this energy type in the cost is 43.25%. In the light of these data, the MAPE value for energy consumption forecasts using the LSTM model was 0.45%, which shows that the model is able to forecast with high accuracy. As a result, a solar power plant was installed to optimize energy consumption, and in 2023 60% energy savings were achieved in summer and 25% in winter. The electricity consumption forecasting results have been an essential guide in planning strategic initiatives to enhance factory efficiency. Following improvement efforts aimed at reducing energy consumption and lowering the carbon footprint, significant optimizations in processes and layouts have been made at specific bottleneck points within the facility. These improvements have led to savings in labor, time, and space, and have reduced unit production costs.

Futus is a term used by the Dawan people to refer to woven fabrics produced by the ikat technique which is applied in the yarn dyeing process. This woven cloth is one of the local pearls of wisdom passed down from generation to generation in the Dawan Tribe, North Central Timor District. The dyeing process is an important stage in the processing of woven fabrics that use plants as dyes. This study aims to reveal the types of natural coloring plants for woven fabrics, the plant organs used, and how they are processed. The semi-structured interview method was used in focus group discussions with 38 respondents who are weavers. This study revealed that there are 17 species from 12 plant families that are used as dyes for woven fabrics of the Dawan tribe in the North Central Timor District. Turmeric (Curcuma longa L.) is the most widely used plant. The part of the plant most used as a dye is the leaves, followed by rhizomes, roots, bark, fruit, and seeds. The processing of plants into dyes for woven fabrics consists of two ways, namely boiling and without boiling, each of which produces a different color with a different fixative mixture.

The high electricity and water consumption in industrial textile dyeing processes represents an environmental and economic challenge, requiring optimization strategies to reduce costs and impacts toward cleaner production. This work proposes an optimization model to minimize costs associated with water and electricity consumption in industrial textile dyeing processes. The model has a Mixed Integer Linear Programming (MILP) formulation. The objective function to be minimized is the total process costs. The constraints consider production capacity, daily production limits, and specific costs per material. A case study was conducted in a real industrial process for three types of tissue: cotton, polyester, and polyamide. The model was coded in GAMS and the CPLEX solver was used to solve the problem. The results showed that water consumption accounted for 78.2% of the total cost in the optimal solution. Using the same model, an alternative simulation was performed, replacing four smaller-capacity machines with a single larger-capacity machine, resulting in a marginal reduction in total costs. Simulations were also performed to replace the current machines with highly efficient automated HT (High Temperature) machines, indicating a potential 71.39% reduction in water consumption costs. The conclusion is that the proposed model is effective for optimizing textile dyeing processes, balancing operational efficiency and sustainability, and is applicable in complex industrial scenarios.

Theoretical study of chlordecone and surface groups interaction in an activated carbon model under acidic and neutral conditions

Metabolism and enzymology of cyanide/metallocyanide biodegradation by Fusarium solani under neutral and acidic conditions

This review discusses the properties of liposomes and their role in the textile process, including textile preparation and dyeing. Liposomes have a surface activity effect due to a hydrophilic head group and hydrophobic hydrocarbon tail. Its preparations do not tend to foam, which advantageously distinguishes them from other textile auxiliaries. According to the carrier role of liposomes, they can be used in several textile processes such as textile finishing and dyeing with several types of dyes and fibers. Each application is discussed in this review paper. Several types of dyes are encapsulated by liposomes in the dyeing process and their presence indicates that they have retardant and leveling effects according to their gradual release of dyes. In addition, the presence of liposomes in the textile process can improve the mechanical properties of textile products, resulting in better wash fastness properties and leveling effect and handle properties. The best character of liposomes is a reduction in temperature of process resulting to save energy and they are environment degradable materials.

The ethylenediamine-N,N′-disuccinic acid (EDDS) was utilized to form Fe-EDDS complex to activate peroxymonosulfate (PMS) in the electrochemical (EC) co-catalytic system for effective oxidation of naphthenic acids (NAs) under neutral pH conditions. 1-adamantanecarboxylic acid (ACA) was used as a model compound to represent NAs, which are persistent pollutants that are abundantly present in oil and gas field wastewater. The ACA degradation rate was significantly enhanced in the EC/PMS/Fe(III)-EDDS system (96.6%) compared to that of the EC/PMS/Fe(III) system (65.4%). The addition of EDDS led to the formation of a stable complex of Fe-EDDS under neutral pH conditions, which effectively promoted the redox cycle of Fe(III)-EDDS/Fe(II)-EDDS to activate PMS to generate oxidative species for ACA degradation. The results of quenching and chemical probe experiments, as well as electron paramagnetic resonance (EPR) analysis, identified significant contributions of •OH, 1O2, and SO4•− in the removal of ACA. The ACA degradation pathways were revealed based on the results of high resolution mass spectrometry analysis and calculation of the Fukui index. The presence of anions, such as NO3−, Cl−, and HCO3−, as well as humic acids, induced nonsignificant influence on the ACA degradation, indicating the robustness of the current system for applications in authentic scenarios. Overall results indicated the EC/PMS/Fe(III)-EDDS system is a promising strategy for the practical treatment of NAs in oil and gas field wastewater.

We evaluated the stabilities of kojibiose and sophorose when heated under neutral pH conditions. Kojibiose and sophorose epimerized at the C-2 position of glucose on the reducing end, resulting in the production of 2-O-α-D-glucopyranosyl-D-mannose and 2-O-β-D-glucopyranosyl-D-mannose, respectively. Under weak alkaline conditions, kojibiose was decomposed due to heating into its mono-dehydrated derivatives, including 3-deoxy-2,3-unsaturated compounds and bicyclic 3,6-anhydro compounds. Following these experiments, we propose a kinetic model for the epimerization and decomposition of kojibiose and sophorose by heat treatment under neutral pH and alkaline conditions. The proposed model shows a good fit with the experimental data collected in this study. The rate constants of a reversible epimerization of kojibiose at pH 7.5 and 90 °C were (1.6 ± 0.1) × 10−5 s−1 and (3.2 ± 0.2) × 10−5 s−1 for the forward and reverse reactions, respectively, and were almost identical to those [(1.5 ± 0.1) × 10−5 s−1 and (3.5 ± 0.4) × 10−5 s−1] of sophorose. The rate constant of the decomposition reaction for kojibiose was (4.7 ± 1.1) × 10−7 s−1 whereas that for sophorose [(3.7 ± 0.2) × 10−6 s−1] was about ten times higher. The epimerization reaction was not significantly affected by the variation in the buffer except for a borate buffer, and depended instead upon the pH value (concentration of hydroxide ions), indicating that epimerization occurred as a function of the hydroxide ion. These instabilities are an extension of the neutral pH conditions for keto-enol tautomerization that are often observed under strong alkaline conditions.

Molecular mechanism for stabilization of a mutant α-galactosidase A involving M51I amino acid substitution by imino sugars

The aim of this research was to examine water contamination resulting from the fabric dyeing process in the Lahanam area, located in Songkhone district, Lao PDR. Lahanam is a famous village known for its fabric dyeing and weaving activities, utilizing both natural and chemical dyes which result in the discharge of colors into local water resources. Water samples were collected from three different sources: household dyeing water (HD), community wastewater (CW) and the nearby river, Xebanghieng (XR). Qualitative and quantitative analyses were performed on the water samples. Atomic Absorption Spectroscopy (AAS) was employed to measure the presence of heavy metals such as lead (Pb), arsenic (As), cadmium (Cd) and mercury (Hg). Additionally, tests were conducted to determine the biological oxygen demand (BOD), dissolved oxygen (DO), ammonia contents and pH in the water of Xebanghieng. The results revealed that HD samples contained significantly higher amounts of all four heavy metals (lead 0.217 mg L–1, cadmium 0.105 mg L–1, arsenic 0.029 mg L–1 and mercury 0.0014 mg L–1), with lead, cadmium and arsenic exceeding standard limits. These data indicate potential environmental impact of chemical dyeing in the village in the future. Therefore, it is recommended to replace the current dyeing process with more sustainable alternatives, such as natural dyes. GRAPHICAL ABSTRACT HIGHLIGHTS The water quality of the river in the dyeing village in Lao PDR Heavy metals in wastewater after dyeing process. The impact of chemical dyeing.

Sustainable dyeing of cotton fabrics with carbene dyes: Covalent cross-linking for auxiliary-free coloration.