Search Results (76)

The development of bio-based inks represents a promising strategy to reduce the environmental impact of digital printing technologies. This study investigates the formulation and performance of water-based inks incorporating two renewable pigments: a fermentation-derived indigo pigment and a plant-extracted yellow pigment. Special attention was given to dispersion optimization of the poorly water-soluble indigo pigment. Extended mechanical dispersion (115 h in a ball mill) proved critical to achieve colloidal stability, enabling the preparation of inks that met standard rheological and physicochemical criteria for inkjet printing with piezoelectric printheads. Both inks were applied on a variety of substrates, including cotton, polyester, leather, and kraft paper, pre-treated, in the case of the textiles, with either a cationic biopolymer or a synthetic polyurethane-based binder. Colorimetric evaluation confirmed effective deposition and uniformity, with the indigo ink producing deep blue hues and superior overall fastness than the yellow ink, particularly in washing and rubbing tests. The yellow pigment ink showed good stability but once applied to the fabric, the resulting print exhibited poor fastness, particularly against light exposure, indicating limited durability of the coloration on the textile. Shelf-life analysis of the indigo ink revealed a decline in viscosity and surface tension over time, though the colour and particle size remained stable, particularly under room temperature conditions. These findings confirm the potential of fermentation-derived indigo as a robust bio-based alternative to synthetic dyes and its superior performance in relation to other nature extracted pigments, which, although facilitating ink preparation due to their higher water solubility, result in lower-fastness prints. Full article

Growing demand for sustainable materials has intensified research into eco-friendly alternatives to conventional and synthetic leathers. Traditional bovine leather and its chromium-tanning process heavily contribute to water pollution, toxic waste generation, and carbon emissions, while synthetic leather derived from Polyvinyl Chloride (PVC) and polyurethane (PU) presents challenges related to fossil fuel dependence and non-biodegradability. This review explores bio-based and sustainable leather substitutes that are made of plants, microbial cellulose, and mycelium fungi. Plant-based leather substitutes such as Vegea^®, Desserto^®, and Piñatex^® use agricultural waste products to create durable, partially biodegradable composites. Microbial cellulose from kombucha fermentation offers material with good physical and aesthetic properties. Mycelium leather, derived from fungal biomass, demonstrates potential for scalable and low-impact production. Comparative analyses of mechanical and physical properties show that mycelium composites are approaching industrial standards, though challenges remain regarding tensile strength, water resistance, and process standardization. Despite current limitations, bio-based leathers, particularly mycelium composites, offer a promising way toward circular material innovation and carbon-neutral manufacturing in fashion, automotive, design and other industries. Full article

Beykoz Leather and Shoe Factory is an important industrial heritage site in Istanbul because of its cultural, social, historical, and symbolic value. Reusing it as a filming location has created a long-running controversy about its suitability. Therefore, the purpose of this paper is to evaluate the compatibility of adaptive reuse of this industrial heritage site in the context of assigning an alternative use compared to its original function. This paper originally proposed a three-charter rubric system, which uses the three international heritage frameworks, turned into rubrics, to gauge how appropriately (or not) the transformation of this site is handled. The process identified a critical juncture and two phases of progressive transformation. The first stage of adaptive reuse limited the site primarily to filmmaking, successfully preventing abandonment through minimal intervention but offering restricted public access. After 2020, a second stage expanded public accessibility and introduced new functions, creating a more vibrant cultural and creative hub besides demonstrating a more effective adaptive reuse approach. The findings of this study suggest that reuse is an appropriate option for extending the lifespan of abandoned buildings. However, it should be highlighted that physical maintenance simply prevents demolition, whereas offering engaging activities promotes the vitality and longevity of the structures. In a complex industrial heritage site, quasi-public use is a short-term strategy. However, proposing public uses and activities helps prolong the life and vitality of industrial heritage sites that may no longer be used for production purposes. It has been revealed that a holistic strategy for reuse should involve the incorporation of various stakeholders in the process, while considering the sociocultural history and needs of the community, ultimately resulting in a positive impact on the vitality of this important industrial heritage site. The study concludes that the rubric-based application of the three heritage charters—the Burra Charter (BC), the Dublin Principles (DP), and the Nizhny Tagil Charter (NT)—provides an effective framework for assessing the appropriateness of new uses. This approach reveals the impacts of adaptive reuse by rating individual buildings according to their degree of compliance with heritage principles, thereby demonstrating how reuse decisions influence the long-term lifespan of industrial buildings on the site as well as their effects on community engagement. Full article

Recently, increasing attention has been paid to the application of sulfonic acids as alternative materials for the pickling process. The aim of the present study was to investigate the action of pickling with p-toluenesulfonic acid monohydrate on derma’s collagen and the influence of this action on subsequent processes and properties of chromed and crust leather. The application of p-toluenesulfonic acid monohydrate in the pickling process led to a similar effect on collagen compared with conventional process. The solutions after experimental pickling contained lower amounts of total dissolved solids, total suspended solids, and chlorides. The chrome tanning process is improved after the pickling with p-toluenesulfonic acid monohydrate: the exhaustion of chromium compounds reaches 98%, while after conventional pickling, it is only 68.7%; accordingly, lower amounts of basic chromium sulfate can be used for chrome tanning to achieve the same chromium content in the wet blue leather. The crust leather produced after experimental pickling has properties close to the conventional one. Full article

The growing demand for sustainable alternatives to animal and synthetic leathers has accelerated interest in mycelium-based materials as an eco-friendly solution for the fashion industry. This study explores the potential of mushroom mycelium to create leather-like materials that align with circular fashion principles. Five species of edible and medicinal mushrooms were cultivated on sawdust substrates and evaluated for their growth performance, physical properties, and suitability as leather substitutes. Growth analysis revealed distinct species-specific behaviors: Cubamyces flavidus and Lentinus squarrosulus exhibited rapid colonization, achieving full substrate coverage within five days and forming dense mycelial networks at 14 days. In contrast, despite growing more slowly, Sanghuangporus vaninii and Ganoderma gibbosum formed thicker, more compact mats that might be suitable for strong leather-like materials. Visual and structural assessments showed diverse textures, colors, and hyphal architectures resembling natural leather. Physical characterization revealed shrinkage ranging from 13.17% to 24.09%, higher than for cow tanned leather (>5%) and PU microfiber (0.1–1.2%), suggesting a need for stabilization treatments. Apparent densities ranged from 0.13 g/cm³ to 0.30 g/cm³, lower than those of cow leather (0.49 g/cm³) and PU leather (0.38 g/cm³), highlighting species-specific hyphal structures that influence flexibility, porosity, and strength. SEM imaging confirmed the presence of interwoven hyphal mats resembling the fibrous architecture of natural leather, with S. vaninii showing the most uniform and continuous structure. Water absorption was significantly higher in mycelium sheets, consistent with their microporous nature, though S. vaninii showed the lowest uptake, reflecting possible natural water absorption. Thermogravimetric analysis revealed three-stage degradation profiles, with S. vaninii and G. gibbosum retaining >35% mass at 400 °C, indicating strong thermal stability for processing techniques such as hot pressing and finishing. Overall, the results demonstrate mycelium-based leathers as a biodegradable, low-impact alternative that can replicate the visual and functional characteristics of traditional leather, with opportunities for further improvement in substrate optimization, eco-tanning, surface coating, and scalable production toward a sustainable fashion future. Full article

Footwear is traditionally manufactured using non-biodegradable polymers and leather, raising well-documented environmental and health concerns related to their production and disposal. This study explores polyhydroxyalkanoates (PHAs) as sustainable alternatives for bio-based footwear components. A stable aqueous suspension of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) was successfully formulated and applied to cotton fabrics via knife-coating. Various formulations, with and without additives and employing natural or synthetic thickeners, were evaluated in terms of surface morphology, wettability, permeability, and durability. The 10% PHBHHx formulation provided the best balance between material efficiency, coating uniformity, and surface performance. Additives and thermal treatment both influenced wettability, reducing contact angles and enhancing water vapor permeability. Notably, coatings with additives and hot pressing exhibited the highest permeability (68.0 ± 3.1 L/m²/s; 651.0 ± 5.4 g/m²/24 h), while additive-free, non-pressed coatings showed significantly lower values (19.5 ± 4.4 L/m²/s; 245.6 ± 66.2 g/m²/24 h), likely due to excessive compaction. Abrasion resistance remained excellent across all samples, especially with thermal treatment, withstanding 51,200 cycles. Washing resistance results revealed a synergistic effect between additives and heat, promoting long-term hydrophobicity and coating adhesion. Overall, PHBHHx coatings demonstrated potential to enhance water resistance while maintaining breathability, representing a sustainable and effective solution for functional and technical footwear applications. Full article

Phytic acid, as a natural originated compound with multi phosphate side groups, is known to increase the corrosion protection and thermal resistance of the coatings. In this study, two different acrylic emulsion polymers containing epoxy and silane reactive functional groups (glycidyl methacrylate (GMA) and vinyltriethoxysilane (VTES)) were synthesized via emulsion polymerization and mixed with phytic acid (PA) solution in different ratios (5, 10, 15 wt%) for use as binders in leather finishing applications. The colloidal stability, particle size distribution, and chemical structures of the synthesized polymers were characterized through comprehensive analyses. The resulting reactive copolymer dispersions were used as binders in finishing formulations and applied to crust shoe upper leathers The coating performance was evaluated in terms of rub fastness, flex resistance, water spotting, and thermal resistance, using the unmodified reactive acrylic binders (G0 and V0) as reference systems to assess the improvements achieved. Both phytic acid-modified binders exhibited strong film integrity and maintained high dry rub fastness up to 2000 cycles and wet rub fastness up to 250 cycles at phytic acid concentrations of 5–10 wt%. Increasing the phytic acid content beyond this range led to reduced dispersion stability and partial loss of coating performance. The results confirm that incorporating moderate levels of phytic acid into reactive acrylic emulsions enhances coating durability and thermal resistance without compromising film appearance, offering a safer and more sustainable alternative to conventional crosslinking systems for leather finishing applications. Full article

Keratinous wastes, generated from various industries such as poultry processing, slaughterhouses, and salons, accumulate in the environment due to their slow degradation caused by high disulfide cysteine bonds. Traditional methods of managing these wastes, including incineration, composting, open-air burning, and landfilling, have several disadvantages, such as environmental pollution, release of toxic compounds, and breeding of pathogenic and multidrug-resistant microorganisms. Microbial keratinases, produced by bacteria, fungi, and actinomycetes, offer an eco-friendly alternative for valorizing keratinous waste into valuable peptides and amino acids. The biodegradation of keratinous biomass involves four sequential steps: adhesion, colonization, production of keratinolytic enzymes, and breakdown of the keratin substrate. Optimization of culture conditions, such as pH, temperature, substrate concentration, and metal ions, can enhance keratinase production for industrial applications. Keratinases have multifaceted applications in various sectors, including cosmetics, organic fertilizers, leather treatment, animal feed, detergents, and pharmaceuticals. This review highlights the need to explore keratinolytic strains further and improve keratinase yields to develop sustainable solutions for keratinous waste management and generate value-added products, promoting a circular economy. The techno-economic considerations and current limitations in industrial-scale keratinase production are also discussed, emphasizing the importance of future research in this field. Full article

A mycelium is a network of hyphae that possesses the ability to self-assemble and grow into various shapes, acting as a natural binder that minimises the need for intensive chemical and energy processes, making it an alternative capable of forming structures that may eventually outperform traditional fibres such as animal leather and polyester. In this work, two mycelium mats were created, and their thickness, water absorption, coverage, and tear strength for the sewing process were determined. Fibre mats were grown in vitro or on a jute substrate. The mats were treated with salt, tannin or citric acid solutions, then air- or oven-dried. In general, the treatment that least modified the colour and appearance of the mycelium mats was citric acid, and when dried by airflow, the thickness averaged 1.4 mm. The highest tear strengths were 10.55 N/mm and 12.7 N/mm for the mycelium mats treated with citric acid without and with jute, respectively. A high percentage of water absorption was observed, reaching 267% (mycelium mats treated with tannins and dried at 65 °C) and 28% (mycelium mats treated with citric acid and air-dried). In general, all mycelium mats can be sewn, except for those treated with citric acid, which have a viscous texture and require slow sewing to prevent the mycelium from breaking. The Trametes fungus can be utilised in the production of mycelial materials, allowing for the optimisation of growth conditions to obtain mycelial mats that meet the requirements for use as an environmentally friendly alternative in the textile and related industries. Full article

Vegetable tannins (VTs) are natural polyphenolic compounds widely used in leather tanning as sustainable alternatives to chrome-based processes. Traditionally, only a limited number of commercially available tannins, such as mimosa, quebracho, and chestnut, are employed globally, often requiring long-distance transportation with associated environmental and economic costs. This review systematically explores recent advances (2015–2025) in the identification and evaluation of alternative VT sources derived from underutilized plant species in Africa and Asia. Chemical composition, extraction efficiency, and tanning performance, including hydrothermal stability, tensile strength (TS), elongation at break (EB%), and tear strength (Ts), are critically analyzed and compared with conventional agents. Particular focus is given to the tannin/non-tannin ratio (T/N), a key indicator of tanning potential. Promising results were found for extracts from Acacia xanthophloea, Cassia singueana, Solanum incanum, Pontederia crassipes, and Xylocarpus granatum. Preliminary environmental assessments (COD, BOD, TDS) also suggest comparable impacts to standard tannins. However, performance variability due to species, plant part, seasonality, and extraction conditions remains a challenge. This review underscores the potential of regionally sourced VTs to support proximity-based economies and reduce the environmental footprint of the leather industry, while highlighting the need for further studies to optimize extraction protocols and scale industrial application. Full article

The purpose of this paper is to evaluate the thermophysiological comfort of pineapple bio-based nonwoven material as a sustainable alternative to natural leather and synthetic polymer-coated materials by analyzing both the objective parameters of the material and subjective user feedback by wearing a skirt made from the same material. Considering the increasing demand for sustainable materials alternatives, the study aims to determine whether this material can offer acceptable comfort during wear. The research included two commercially available pineapple, bio-based, nonwoven materials that differed in their finishing. Sample S1 contained 5% Bio-PU and 5% conventional PU, and sample S2 contained 10% conventional PU. Objective parameters such as thermal resistance (R_ct), water vapor resistance (Ret) and air permeability were measured. For the subjective evaluation, ten female subjects wore the pineapple bio-based material skirts under controlled environmental conditions. Sample S1 showed lower R_ct values and slightly lower Ret combined with higher air permeability, which correlated with better subjective comfort evaluation. Although both samples showed high R_et values (S1 = 60.57 Pa²/W; S2 = 84.80 m²K/W) indicating limited vapor transfer, sample S1 was perceived as more comfortable, which was effected by better air permeability (S1 = 11.3 mm/s; S2 = 2.65 mm/s). Overall, S1 is more suitable for indoor use and for a shorter wear duration, while S2 may be better for cooler outdoor environments. Full article

Recently, increased global awareness of environmental sustainability and ethical consumerism has amplified the demand for sustainable alternatives to animal-derived leather. Traditional leather manufacturing faces significant ethical and ecological challenges, including greenhouse gas emissions, excessive water consumption, deforestation, and toxic chemical usage. Vegan leather has emerged as a promising solution, predominantly fabricated from petroleum-based synthetic materials such as polyurethane (PU) and polyvinyl chloride (PVC). However, these materials have sustainability limitations due to their non-biodegradability and associated environmental burdens. To overcome these issues, this review critically explores the feasibility of developing vegan leather using gel-based materials derived from natural and synthetic polymers. These materials offer precise structural controllability, excellent biodegradability, and the potential for significantly improved mechanical performance through hybridization and nanocomposite strategies. Despite their promising attributes, gel-based materials face significant limitations, including insufficient tensile strength, poor abrasion resistance, susceptibility to swelling, limited long-term stability, and challenges in scaling up for industrial production. This paper outlines the structural and physical properties required for viable leather substitutes, reviews opportunities provided by gel-based materials, addresses associated technical challenges, and proposes comprehensive strategies for enhancing mechanical properties and developing sustainable, eco-friendly production processes. Future research directions emphasize hybrid composite development, nanoparticle integration, circular manufacturing processes, and multi-disciplinary collaboration to establish gel-based vegan leather as a viable, sustainable, and market-competitive alternative to conventional animal leather. Full article

The world has recently witnessed the dire consequences of microbial infections in the form of the spread of COVID 19. Like viruses, bacterial infections too are a serious global health concern, especially because of the evolution of multidrug-resistant (MDR) bacterial populations. MDR bacteria are a result of the mindless use and misuse of antibiotics all over the world. Hence, there arises a need to find alternative strategies to effectively combat bacterial infections; all the more so for MDR bacterial infections. A lot of research has been conducted to find alternative antibacterial strategies such as phage therapy, the synthesis of antimicrobial peptides, the development of CRISPR-Cas systems, the incorporation of pro- and pre-biotics into our food or as supplements, and the development of bactericidal nanotechnology and antibacterial materials. Of these many strategies, this review focusses on the last one—the development of antibacterial materials. This article explores the potential of plant-derived natural colorants to serve as effective antibiotic materials to be used in various industries ranging from food, textile, paper, and leather to the pharmaceutical industry. Some major advantages of developing plant-derived natural colorants into antibacterial materials is that many of them possess inherent medicinal properties, they are biocompatible, non-toxic for humans, and biodegradable, and hence environment friendly. Many plant-derived natural colorants, like curcumin, indigo, lawsone, emodin, etc., have already been well studied for their antimicrobial properties. This review article aims at integrating some relevant studies to offer a cohesive overview of the current state of knowledge on the antibacterial properties of plant-derived natural colorants. Full article

The leather tanning industry generates a substantial quantity of solid waste, which, in part, is discarded in the environment in landfills or incinerated. One alternative end-of-life solution is to manufacture engineered materials by forming composites with a thermoplastic polymer/binder. In this work, leather fibres (LFs) were melt-compounded into partially bio-based thermoplastic polyurethane (TPU), at leather fibre contents between 10 and 30% (TPU/LF), followed by compression moulding or 3D printing. The results showed that the incorporation of LF into the polymer matrix produced materials with a Young’s modulus comparable to that of leather. The melt extrusion processing influenced the polymer chain orientation and the resulting mechanical performance. The cyclic stress softening and abrasion resistance of the TPU/LF materials were evaluated to understand the potential of this material to be used in the footwear industry. The level of LF incorporation could be tailored to produce the specific targeted mechanical properties. This work demonstrates that LF could be used to produce materials with a high potential to be used in the fashion industry. Full article

The environmental impact and resource demands of traditional leather manufacturing have driven the search for sustainable alternatives. Fungal mycelium leather, recognised for its eco-friendly and renewable characteristics, has emerged as a promising option. This study established a cyclic freeze-thaw dehydration protocol for preparing mycelial leather using Ganoderma mycelium produced through liquid fermentation. By precisely controlling the fermentation parameters (pH 5.5, 150 rpm agitation, 28 °C), the liquid fermentation process ensures uniform mycelial growth, which is critical for subsequent structural enhancement during freeze-thaw cycles. After three freeze-thaw cycles were performed at −15 °C, uniformly distributed ice crystals facilitated effective water removal, achieving a minimum moisture content of 47.6%. The optimized freeze-thaw process produced membranes with a tensile strength of 6.22 MPa and elongation at break of 18.92%, demonstrating high mechanical performance. The freeze-thaw process was demonstrated to enhance structural integrity and mechanical properties while offering reduced energy consumption compared to conventional dehydration methods. This research provides a theoretical foundation and technical guidance for optimising fungal mycelium leather production and contributes to the development of sustainable bio-based materials for industrial applications. Full article