Search Results (65)

Defined natural products are often framed as intrinsically safer multi-target alternatives to selective drugs, but this assumption is not pharmacologically justified. This critical review evaluates product-specific adjunctive evidence in respiratory allergy, inflammatory bowel disease, type 2 diabetes, depression, and insomnia. MEDLINE/PubMed records published from 2020 to 23 June 2026 were prioritized, while earlier pivotal randomized trials and quantitative safety studies were retained. Evidence was gated by product identity, human exposure, exposure-compatible target engagement, incremental efficacy, and safety boundaries. Nigella sativa oil improved Asthma Control Test scores by 1.5 points over placebo after 4 weeks, although the clinical importance is uncertain and FEV1 was not significantly improved. Curcumin plus mesalamine induced remission in mild-to-moderate ulcerative colitis (53.8% versus 0%), whereas indigo naturalis produced strong response rates but is constrained by pulmonary arterial hypertension. Berberine improves glycemic surrogates but lacks cardiovascular or renal outcome evidence and shows commercial potency variability. Saffron has a short-term antidepressant signal, while St John’s wort combines extract-dependent efficacy with CYP3A4/P-glycoprotein induction. Overall, selected defined natural products may merit narrow adjunctive roles, but undefined mixtures should not be treated as mechanistically established interventions without batch-level characterization, human pharmacokinetics, objective endpoints, and prospective interaction surveillance. Full article

The fashion industry generates a major environmental impact, requiring integrated sustainable approaches. This study integrates six thematic axes—sustainability, modular design, natural materials, eco-friendly dyeing, multidimensional comfort and consumer perception, and radial composition—into an integrative framework for sustainable design. The mixed-methods methodology comprises four stages: (I) a quantitative stage (questionnaire, n = 150); (II) an experimental stage (testing of comfort characteristics of linen fabrics according to ISO standards, and indigo dyeing through three techniques: uniform, tie-dye, and shibori); (III) a digital design stage in CLO3D and physical fabrication of the prototype; (IV) a prototype testing and validation stage (panel, n = 20). The prototype provides functional adaptability through 8 design configurations, versatility through reversibility, and aesthetic diversity through the radial composition, yielding 16 distinct wearing modes within a single product. Panel evaluation confirms high prototype acceptance (M = 4.81–4.95), and physical interaction with the prototype significantly increases purchase intention compared with conceptual evaluation (M_pre = 3.54; M_post = 4.60; d = 2.04; p < 0.001). The contribution validates a framework that integrates six dimensions of sustainable fashion into a coherent clothing design model, demonstrating design’s role as a practical instrument in the sustainability transition, with applied implications for designers and researchers. Full article

Fifty-five batik textiles produced along coastal Java in the late 19th to early 20th century were analysed to study the red dyes and the cotton fabrics. Surface-Enhanced Raman Spectroscopy (SERS) classified the dyes into six groups and identified 70% of the samples as Morinda. High-Performance Liquid Chromatography coupled with a diode array detector and tandem Mass Spectrometry (HPLC-DAD-MS/MS) confirmed the SERS results and identified synthetic dyes in the remaining samples, which were used either alone or in mixtures with Morinda or indigo. Synthetic alizarin (C.I. 58000, Mordant Red 11) was the most frequently detected synthetic dye. Auramine O (C.I. 41000, Basic Yellow 2), fuchsin (C.I. 42510, Basic Violet 14), and rhodamine B (C.I. 45170, Basic Violet 10) were occasionally detected. The results also highlighted two possible types of Morinda and two variations of synthetic alizarin. The shades obtained from mixtures of natural and synthetic dyes were visually indistinguishable from those obtained with pure natural or synthetic dye, as confirmed by colourimetry. The variety of dyes and cotton fabrics shared across batik producers makes it challenging to attribute unsigned batiks to specific workshops. Nevertheless, this study demonstrated that synthetic dye uptake during this period was limited and experimental, with natural Morinda remaining the preferred choice despite the availability of European synthetic alternatives. Full article

This study explores the natural dyeing of banana pseudo-stem (BSS) fibers as a sustainable material for plant-based leather applications through low-energy processes. Two dye types, lac dye and indigo blue, were applied, and the optimal dyeing parameters were systematically determined. Optimal lac dyeing was achieved using pre-mordanting with a binary mordant system comprising tannic acid and aluminum potassium sulfate (5 g L⁻¹ each), a dye concentration of 10% owf, a pH of 4.23, and a dyeing duration of 6 h. For indigo dyeing, the optimal conditions involved 500 g L⁻¹ wet indigo, 30 g L⁻¹ sodium hydroxide, and 40 g L⁻¹ thiourea dioxide, with a reduction step at 30 °C for 30 min. The dyed samples exhibited good to excellent perspiration fastness in terms of staining, while color change ratings remained low due to the intrinsic sensitivity of natural dyes. Light fastness was rated fair. The dyed BSS was subsequently laminated onto a polypropylene (PP) nonwoven substrate and coated with natural rubber (NR) latex, yielding bursting strengths of 51.8–54.8 psi. Moisture management testing confirmed inherent waterproof properties. Overall, this study presents a resource-efficient approach to transforming agricultural residues into sustainable, plant-based leather alternatives. Full article

A small dyer’s handbook in Dr. Georg Kremer’s archive presents unexpected challenges. The handwritten recipes can be dated back to the early 19th century. The author must have been an experienced dyer, who wrote down detailed instructions for dyeing or printing on cotton, wool and silk. More than 80 dyed textile samples were sewn or glued into the book. A colourful palette is achieved with natural dyes such as indigo, cochineal, madder, alkanna, annatto, turmeric and quercitron. Furthermore, inorganic pigments like Prussian blue and chrome yellow were used. Unfortunately, the text is characterized by regional accent and inconsistent spelling. Language analysis was able to assign the origin of the author to the Vogtland, a region in Germany that covers parts of Bavaria, Thuringia and Saxony. The spelling or misspelling of the words may leave readers with a smile, but also make it difficult to figure out ingredients, chemicals or dyes. The measurement units given in the recipes are problematic. Additionally, vessels of vague volumes such as hand buckets or coffee cups are used. In this study, the content of the notebook is evaluated, and initial reproductions are carried out to find out how useful these recipes are for further research. Full article

Conventional extraction of indigo, a vital natural dye, provides low yields and has a negative environmental impact. However, microbial synthesis has emerged as a sustainable alternative. In this study, we describe the optimization of indigo biosynthesis in an engineered Escherichia coli strain called E216. This strain carries, on a replicative plasmid, the styAB genes originating from Pseudomonas putida that constitute the monooxygenase biosynthetic pathway of indigo, as well as mdh, encoding malate dehydrogenase, which plays a role in reducing power generation. In this strain, the overexpression of mtr (a gene encoding a transporter of tryptophan (Trp), the precursor of indigo biosynthesis) and acrA (a gene encoding a protein involved in indigo efflux) was found to substantially enhance indigo yields. Consistently, knocking out these two genes using CRISPR-Cas9 significantly reduced indigo production, whereas it was restored through the complementation of these mutants. This study thus revealed that stimulating tryptophan uptake and indigo efflux, the latter of which limits indigo’s toxic intracellular accumulation, has a positive impact on indigo yields. Furthermore, a comparative mass spectrometry-based proteomic analysis of E216 grown in fermentation medium with or without tryptophan supplementation, integrated with data-independent acquisition (DIA), revealed the global impact of tryptophan supplementation on cellular metabolism. This analysis identified upregulation of key proteins and enriched metabolic pathways under conditions of tryptophan supplementation. Integrating the results of the genetic engineering and proteomic analysis establishes a strong scientific and practical basis for developing a highly efficient method for the green industrial production of indigo using engineered E. coli strains. Full article

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

A simple method employing dextrose as a capping agent was adopted for making MgAl₂O₄@MgO (AM), 5%NiO-MgAl₂O₄@MgO (AMNi), 5%CoO-MgAl₂O₄@MgO (AMCo), and 5%CuO-MgAl₂O₄@MgO (AMCu) nanocomposites. The average particle sizes, determined via SEM, were in the range of 21.6–51.4 nm, 9.8–13.8 nm, 19.1–32.2 nm, and 9.2–31.2 nm for AM, AMCu, AMNi, and AMCo, respectively. The nanosorbents exhibited type IV isotherm curves and type H3 hysteresis loops, signifying mesoporous properties. The AM, AMCu, AMNi, and AMCo exhibited surface areas of 69.47, 95.87, 86.23, and 75.87 m²/g, respectively. The pseudo second order described the indigo carmine (IDC) sorptions onto AM, AMCu, AMNi, and AMCo. The liquid film diffusion regulated IDC sorption on AMNi and AMCo, whereas the intraparticle diffusion was the dominant model on AM and AMCu. The AMCu’s showed a q_t value of 127 mg g⁻¹ from a 50 mg L⁻¹ IDC solution at 20 °C, and 286.2 mg g⁻¹ from a 200 mg L⁻¹ IDC solution at 50 °C, establishing its capability for treating contaminated water. The IDC sorption onto AMCu aligns with the Freundlich model, which may elucidate the elevated q_t value of AMCu. Elevating the temperature induced the IDC sorption on AMCu, indicating its endothermic nature, and the negative ΔG° implied that the IDC sorption by AMCu was spontaneous. A 5.0 and 10.0 mg L⁻¹ IDC concentration in natural water samples was treated by the AMCu, which showed 100.0% efficacy for both groundwater samples; however, its efficacy toward the 5 and 10 mg L⁻¹ IDC in seawater was 99.23% and 89.78%, respectively. The MACu’s efficiency throughout four reuse cycles decreased by only 7.21%, demonstrating excellent stability and reusability performance. Full article

Background/Objectives: Anthocyanins, water-soluble flavonoid pigments with critical roles in plant stress resistance, are not naturally accumulated in cultivated tomato (Solanum lycopersicum) due to an incomplete flavonoid metabolism pathway. In contrast, ‘Black Pearl’ tomato exhibits distinct peel color transitions (from indigo rose to deep purple–red) during ripening, making it an ideal model for investigating the regulatory mechanisms of anthocyanin synthesis. A comprehensive strategy was employed to elucidate these mechanisms, involving transcriptomic (Illumina HiSeq), metabolomic (UPLC-MS/MS), and functional analyses of the ‘Black Pearl’ tomato peel across four developmental stages: mature green (S1), coloring (S2), purple immature (S3), and fully ripened (S4). Results: Transcriptome profiling identified 597 core differentially expressed genes (DEGs) associated with anthocyanin accumulation. Temporal analysis indicated that structural genes and activators peaked at S3, whereas repressive MYBs, including SlMYB76 which peaked at S2, exhibited staged expression. In parallel, metabolomic analysis identified 36 metabolites, with cyanidin and pelargonidin derivatives being characterized as the principal pigments. Functionally, SlMYB76 was confirmed to be a negative regulator, as its transient overexpression reduced anthocyanin content and downregulated SlANS. Mechanistically, direct binding and repression of the SlANS promoter by SlMYB76 were confirmed through yeast one-hybrid and dual-luciferase assays. Furthermore, its physical interaction with the bHLH factor SlJAF13 in the nucleus was demonstrated by Y2H, BiFC, LCI, and Co-IP, supporting the formation of a repressive complex that co-regulates SlANS. Conclusions: A novel SlMYB76-SlJAF13-SlANS regulatory module controlling anthocyanin accumulation in the peel of ‘Black Pearl’ tomato was identified. This discovery enhances the current understanding of the tomato flavonoid regulatory network and provides strategic targets for the genetic improvement of fruit color and anthocyanin content through molecular breeding. Full article

Ceramic membrane technology plays an important role in water and wastewater treatment. Strategic sourcing of various natural mineral resources has contributed to developing low-cost ceramic membranes. The combination with calcination of inorganic and organic wastes from domestic and agricultural activities results in fully sustainable ceramic membrane materials. In this work, ceramic membranes were developed using 96% clay, 2% almond shells and 2% lime. Sintering at 900, 950, and 1000 °C enabled the production of membranes (MK-900, MK-950, and MK-1000) in a clean, simple, and cost-effective manner. The average pore diameter and porosity decreased slightly from 44 to 42 nm and from about 30% to 26% with increasing sintering temperature, while the flexural strength increased from 25 to 40 MPa. The pure water permeability was 68 and 59 L·m⁻²·h⁻¹·bar⁻¹ for MK-900 and MK-950, respectively. Effective color (as Indigo blue) removal of 78% and 92% was observed for MK-900 and MK-950, respectively. More than 90% of the initial permeability was recovered after three cycles of dye filtration using water backwashing at each stage, indicating good fouling resistance of the prepared membranes. Full article

This study has successfully developed a practical and straightforward approach for synthesizing nanocomposites with excellent dye removal potential. The SEM inspection of γ-Al₂O₃ (γ-Al) and MgO/MgAl₂O₄ (Mg/MgAl) nanocomposite showed a mean size of 59.0 and 46.4 nm, respectively, while the TEM results show particles with an average size of 26.63 and 13.4 nm, respectively. The surface area of γ-Al and Mg/MgAl was 50.0 and 69.5 m² g⁻¹, respectively. The study of adsorbing indigo carmine (IC) sorption onto γ-Al and Mg/MgAl presented sorption capacities of 41.6 and 55.9 mg g⁻¹, respectively, and both adsorbents attained equilibrium at 90 min. The highest IC sorption onto Mg/MgAl took place at pH 6.0. It is worth mentioning that raising the IC solution’s temperature from 20 °C to 50 °C increased the q_t to 268 mg g⁻¹. The IC sorption onto γ-Al and Mg/MgAl agreed with the pseudo-second-order model, and the liquid-film diffusion controlled the IC sorption. The Mg/MgAl showed an average removal of 98.2% when tested for removing six dyes at 10 mg L⁻¹, particularly malachite green, methylene blue, fast green, methyl orange, rhodamine B, and basic fuchsin, and the removal efficiency was 93.3% when their concentration increased to 20 mg L⁻¹. The Mg/MgAl nanocomposite performed exceptionally well in natural water samples (seawater and groundwater), indicating its potential applicability in managing water contamination. Full article

Ultraviolet radiation (UVR) represents significant risks to both textile durability and human health. Natural dyes are gaining attention as eco-friendly alternatives to synthetic UV-blocking agents, offering aesthetic and functional benefits. This study explores the UV-protective properties of 100% cotton knit fabrics dyed with natural dyes—indigo, weld, and madder—using different mordanting processes, including materials with mordant abilities such as alum, pomegranate peel, and tannin extracted from quebracho. Twenty samples were evaluated, including undyed, individually treated, and combined dye-mordant formulations. UV protection was assessed through spectral transmittance and Ultraviolet Protection Factor (UPF) measurements before and after washing. The results showed that natural dyes significantly improved the UV resistance of cotton fabrics, particularly when combined with products like pomegranate and the tannin–alum mixture. Notably, some samples demonstrated improved UPF and became darker after washing, such as mordant combinations like tannin with alum. These findings suggest that natural dye, when combined with appropriate mordants, offers a sustainable and effective approach to producing UV-protective textiles. This is particularly valuable in children’s clothing, where chemical safety and sun protection are crucial. Future research should investigate the influence of pH on dye stability and UV-blocking performance to optimise formulations for industrial use and long-term functionality. Full article

Isatis tinctoria L. (Brassicaceae), also known as woad or dyer’s woad, is an ancient plant with a rosy future ahead. Most of the knowledge about woad is related to indigo dye production and its medicinal applications, especially its leaves. The general interest in woad has decreased with the rise of petroleum-based products. However, nowadays this plant is attracting interest again with industries reintroducing natural dyes. To meet the market demand in a sustainable manner, recent studies have focused specifically on woad seeds, leading to a valorization of the whole woad plant. This review provides an overview of the botanical, phytochemical composition, and properties of woad seeds, primarily supporting their cosmetic and pharmaceutical potential. From a chemical point of view, woad seeds mainly contain fatty acids, amino acids, phytosterols and glucosinolates. These compounds have been investigated through their extraction and analytical methods, as well as their properties and industrial applications. Full article

This study focuses on the stabilization of a natural hair dye derived from Lawsonia inermis L. (henna) and Indigofera suffruticosa (indigo). Although various formulations already exist, they are designed for immediate use and cannot be stored. Lawsonia, a primary component of the dye, tends to degrade after release. To ensure its stability, freeze-drying was implemented as a protective measure. Colorimetric analysis confirmed the dye’s ability to maintain an intense, uniform coloration even after multiple washing cycles. Stability tests demonstrate that freeze-drying effectively enhances the dye’s stability and capacity to retain its physical properties and color under various environmental conditions, demonstrating its potential for long-term use. The dye’s pH (5.05) aligns with the natural pH of hair, promoting cuticle sealing and improving hair health. Cytotoxicity tests confirmed the dye’s safety, showing no harmful effects. Gray hair exhibited a total color difference (ΔE) of 64.06 after the initial application, using natural gray hair as a reference. By the third application, ΔE increased to 69.86 and gradually decreased to 68.20 after 15 washing cycles, highlighting its long-term durability. Gray hair exposed to 720 h of UV radiation showed a ΔE of 17.34, whereas dyed gray hair exhibited a ΔE of 2.96 compared to non-UV-exposed samples. This indicates superior resistance to color degradation in dyed hair. Also, SEM imaging revealed the dye’s restorative effects, progressively improving hair cuticle structure with each application. Full article

As part of an implementation in the Peruvian textile industry, the use of different sources to obtain blue hues in alpaca fiber has taken on a prominent role. The present study investigated the optimization of the dyeing process of alpaca fibers using indigo carmine as dye. The methodology was based on a central composite design (CCD) and response surface methodology (RSM) with color strength (K/S) as response variable. The results demonstrate that the independent variables significantly affected the color strength (K/S). In this context, an increase in both mordant concentration (3.9887 g/L) and dyeing temperature (95 °C), coupled with lower exhaust time (30.0019 min), enhanced levels of superficial dye adsorption. Additionally, color fastness properties provided tolerable values according to the gray scale. In conclusion, the optimization of the dyeing process of alpaca fibers using indigo carmine enabled the achievement of a blue shade with satisfactory fastness properties in the fiber yarns. Full article