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This paper aims to study the ability of laccase for decolourisation of reactive dyes in presence and absence of natural and synthetic mediators.

Box–Behnken design was used to optimize the parameters to achieve optimum response value. Preliminary screening using several mediators was performed to evaluate extent of decolourisation for the purpose followed by selection of effective mediators only.

Laccase performs in acidic pH; increase in temperature enhances its activity. Rate of decolourisation depends on laccase and dye concentration, temperature, pH and treatment time. Out of five mediators studied, HBT, BT and VA showed promising results.

Study on decolourisation was conducted for individual dyes. In some cases, dyes are applied in combination which requires further study for authentication of data.

Decolourisation with laccase has been found to be a promising technology in waste water treatment. However, selection of mediator remains a crucial factor.

Reactive dyes are self-hydrolysed over time under natural conditions and extent of decolourisation depends on concentration of dye discharged and time spent. If not decolourised quickly, it imposes restriction on use of river water for irrigation.

In this work, activity of various natural and synthetic mediators alongwith laccase was studied to achieve maximum decolourisation which was not studied earlier.

Five different structural reactive dyes (Reactive Brilliant Blue K-3R, Everacion Blue H-ERD, Moderzol Blue FBR, Atuzol Black B and Moderzol Blue HEGN) were treated with laccase (Denilite II US) in order to determine the optimum decolouration conditions. The experiments showed that laccase had distinct decolouration effects on these five dyes. Under optimum conditions, the colour removal rates of Everacion Blue H-ERD and Moderzol Blue HEGN were over 90%. Furthermore, the effects of different additives, such as acid ion, metal ion, and surfactants on the decolouration rate of Reactive Brilliant Blue K-3R were discussed. The results show that the decolouration rate is significantly promoted through the addition of Cu²⁺ and Al³⁺, while it is inactivated with Fe²⁺ and ion surfactants. Moreover, the COD removal rates of the five dyes are more than 75%.

Nowadays, pigment dyeing is one of the most interesting methods that is applied to make specific designs on denim and fashionable garments. Here, in this research, the bio-washing of pigment dyed denim has been considered with laccases. The desizing and bleaching of denim samples are first carried out and they are subsequently dyed with two types of pigments (Bemacol Blue GF and Ricoprint OSD Serie Blue) through the exhaustion method. The pigment dyed samples are then washed with various laccase concentrations, with and without the use of pumice stones. Color changes, bending and wrinkle recovery are examined. Furthermore, the surface morphology of the products is verified by a scanning electron microscope (SEM) and a Projectina microscope. The samples washed with laccases and pumice stones show higher dye stripping compared with those without the use of pumice stones. The bending properties of the samples treated by pumice stones show desirable results compared with the laccases, but this caused intense damage to the samples. Also, desirable results have been achieved by using laccases in the washing process. Treatment with laccases helps to obtain brilliant samples with decreased staining on the samples with a pocket and also lowers pigment discharge in the effluent.

The purpose of this article is to discuss issues associated with the application big data analytics for decision-making about the introduction of new technologies in the textile industry in the developing world.

The leader–member exchange theoretical framework to consider the nature of the relationships between owners and followers to identify the potential issues that affect decision-making was used. However, decisions to adopt such environmentally friendly biotechnologies are hampered by the lack of awareness amongst owners, intergenerational conflict and cultural impediments.

The article found that the limited use of this valuable technological resource is linked to several factors, mainly cultural, generational and educational factors. The article exposes two key new technologies that could help the industry reduce its carbon footprint.

The study suggests more awareness raising amongst plant owners and greater empowerment of new generations in decision-making in the industry. This study, therefore, bears significant implications for environmental sustainability in the developing world where the textile industry is one of the major polluting industries affecting water quality and human health.

The purpose of this study was to investigate the polyphenoloxidases (PPO) activities in Jerusalem artichoke tubers as well as their inactivation. The following are important for the processing of this food: treatment and conversion used in preserving processes.

The PPO of whole tubers and the separated tuber skins as determined using a modified PPO essay with 0.01 M dopamine.HCl as reactant and photometry (ΔA₄₇₀ plotted against reaction time up to 3 min). Nine varieties used in German tuber production were in the test.

The highest enzyme activity of PPO was in the skin, range from 1,274 up to 3,026 nkat. In the pulps of the tubers nearly traces of PPO could be detected (range: 2 up to 5 nkat). The inhibition of PPO activity in tuber homogenates was investigated in simulated processes which were used in the food industry: heat (drying, pasteurisation) and oxidase inhibitors such as lemon juice, ascorbic and/ or citric acid. The optimum temperature of PPO was 60°C and the inactivation occurred at 85°C. The range of the PPO activity was between pH 5 and 10, with the optimum at pH 7.0. Lemon juice is a natural inhibitor of the PPO activity in fruit and vegetable juices containing Jerusalem artichoke as well as in canning the tubers. Lemon juice combined with citric acid and ascorbic acid is recommended against enzymatic browning reaction.

The characterisation of the parameters which influence enzymatic browning of Jerusalem artichoke tubers during food processing: heat and pH, have not been described before.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

Bacterial cellulose (BC) is an ideal alternative filtering material. However, current functionalization approaches for BC have not been fully discovered industrially as well as academically applying textile processing. This study aims to create a sustainable fabric-like membrane made of BC/activated carbon (AC) for applications in filtration using textile padding method, to protect people from respiratory pandemics.

Fabric-like BC is first mechanically dehydrated then AC is loaded via a textile padding step. The finishing efficacy, properties of fabric-like BC/AC and NaOH pretreatment are analyzed and characterized by scanning electron microscope (SEM), field emission scanning electron microscope (FE SEM), X-ray diffraction (XRD), CIELab color space, color strength (K/S), nitrogen adsorption-desorption isotherm including Brunauer–Emmett–Teller (BET) specific surface area and Barrett–Joyner–Halenda (BJH) pore size and volume.

This research results in a fabric-like BC/AC with pore diameters of 3.407 ± 0.310 nm, specific surface area of 115.28 m²/g and an efficient scalable padding process, which uses 8 times less amount of chemical and nearly 30 times shorter treating duration than conventional methods.

Our globe is now consuming an alarming amount of non-degradable disposable masks resulting in massive trash buildup as a future environmental problem. Besides, current disposable masks requiring a significant upfront technological investment have posed challenges in human protection from respiratory diseases, especially for countries with limited conditions. By combining a sustainable material (BC) with popular padding method of textile industry, the fabric-like BC/AC will offer sustainable and practical values for both humankind and nature.

This research has offered an effective padding process to functionalize BC, and a unique fabric-like BC/AC membrane for filtration applications.

This paper aims to evaluate the bioremediation [chemical oxygen demand (COD) and color removal] of the effluent from the cardboard recycling industry in Yazd, central province of Iran, using mixed fungal culture.

First, the effluent samples from the cardboard recycling industry were cultured on potato dextrose agar medium to isolate native fungal colonies. The grown colonies were then identified using morphological macroscopic and microscopic characteristics to choose the dominant fungi for bioremediations. The mixed cultures of Aspergillus niger, Aspergillus flavus and Penicillium digitatum were finally used for bioremediation experiments of the cardboard recycling industry. A suspension containing 1 × 10⁶ CFU/ml of fungal spores was prepared from each fungus, separately and their homogenous mixture. Sewage samples were prepared and sterilized and used at 25%, 50% and 90% dilutions and pH levels of 5, 7 and 8 for bioremediation tests using mixed fungal spores. Following that, 10 ml of the mixed fungal spores were inoculated into the samples for decolorization and COD removal and incubated for 10 days at 30°C. The amount of COD removal and decolorization were measured before incubation and after 3, 6 and 10 days of inoculation. In this research, the color was measured by American Dye Manufacturer Institute and COD by the closed reflux method. The results of the present study were analyzed using SPSS 21 statistical software and one-way ANOVA tests at p-value < 0.05.

The results of this research showed that the mean decolorization by mixed fungal culture over 10 days at pH levels of 5, 7 and 8 were 44.40%, 45.00% and 36.84%, respectively, and the mean COD removal efficiency was 71.59%, 73.54% and 16.55%, respectively. Moreover, the mean decolorization at dilutions of 25%, 50% and 90% were 45.00%, 31.93% and 30.53%, respectively, and the mean COD removal efficiency was 73.54%, 62.38% and 34.93%, respectively. Therefore, the maximal COD removal and decolorization efficiency was obtained at dilution of 25% and pH 7.

Given that limited studies have been conducted on bioremediation of the effluent from the cardboard recycling industry using fungal species, this research could provide useful information on the physicochemical properties of the effluent in this industry.

This paper aims to investigate the feasibility of potassium permanganate (KMnO₄) as an efficient discharging agent for indigo-dyed denim fabrics and identification of key variables for its cost-efficient implication.

Response surface methodology, which is a statistical technique for the optimization of process variables, was used to study the effect of three key variables, i.e. KMnO₄ concentration, printing paste pH and reaction time on whiteness and strength of discharged printed fabric. Regression models were developed to predict response variables, i.e whiteness, tensile strength and tear strength of discharge printed denim.

It was found that some captivating discharge printing effects could be produced using appropriate KMnO₄ concentration, printing paste pH and reaction time without any significant loss in the fabric strength.

This study highlights the practical implication of KMnO₄ to be used as a safe and effective discharging agent under different conditions and to optimize the parameters using statistical analysis to ensure minimum loss in textile properties. The use of denim has evolved over the decades from a rough and tough workwear to highly fashionable apparel. Various dry and wet processing techniques have been introduced in recent years for the value-addition of denim – discharge printing is one of them. As lab to bulk reproducibility requires some sort of experience and adjustments in main parameters, the practical feasibility on the bulk scale should be adjusted in advance by means of the lab scale experimentation.

The KMnO₄ oxidation process is considered eco-friendly because manganese dioxide, which is formed when permanganate is reduced, can be recycled. Thus, the use of KMnO₄ can be considered as an eco-friendly safe process for the discharging of indigo dyes.

The coatings industry is based on a large number of scientific principles. To be sure, it developed both in ancient and modern times without regard to these. But once an empirical body of knowledge was built up, it became obvious that theoretical underpinnings were not only desirable but necessary if progress were to be made. What are some of the scientific principles which govern coatings technology? Film formation is certainly one. What causes a film to form, and what affects the properties of a film such as cohesion, adhesion, gloss, flexibility, permeability, impact resistance, and a dozen other characteristics? The problem of understanding film formation became all the more important with the advent of waterborne paints, for polymer particles suspended in water are not nearly as prone to form films as are polymer solutes in a solvent.