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Recently, the demand for fungal pigments has increased due to their several benefits over synthetic dyes. Many species of fungi are known to produce pigments and a large number of fungal strains for pigment production are yet to be extensively investigated. The natural pigment from sustainable natural sources has good economic and industrial value. Many synthetic colorants used in textile and various industries have many harmful effects on the human population and environment. Pigments and coloring agents may be extracted from a wide range of fungal species. These compounds are among the natural compounds having the most significant promise for medicinal, culinary, cosmetics, and textile applications. This study attempts to isolate and optimize the fermentation conditions of Penicillium sclerotiorum strain AK-1 for pigment production. A dark yellow-colored pigment was isolated from the strain with significant extractive value and antioxidant capacity. This study also identifies that the pigment does not have any cytotoxic effect and is multicomponent. The pigment production was optimized for the parameters such as pH, temperature, carbon and nitrogen source. Fabric dyeing experiments showed significant dyeing capacity of the pigment on cotton fabrics. Accordingly, the natural dye isolated from P. sclerotiorum strain AK-1 has a high potential for industrial-scale dyeing of cotton materials.

In a strangulation case, when a necktie is used as a murder weapon, the dyed silk single fiber becomes an important evidence sample to solve the crime. Dyed silk single fibers contain elements, such as Cr and Co, which are obtained from dyeing using metal mordants. Currently, there are no nondestructive and sufficiently sensitive elementary analytical methods for the forensic analysis of single fibers. Therefore, in this study, eight commercially available red silk samples were collected and used for total reflection X-ray fluorescence (TXRF) and synchrotron radiation X-ray fluorescence (SR-XRF) spectrometry. Benchtop TXRF detected both S in the silk protein and Cl and Ca, which are elements absorbed from the environment by silkworms, but also Cr, which is a dyeing derivative for metal mordants. The presence of Cr and Zn, in addition to the Zn/Cr signal intensity ratios, was reported to be particularly useful identifiers. In SR-XRF, the presence of Cr, Co, Zn, and Br and the Zn/Cr signal intensity ratios were reported to be useful discriminating indicators. In this study, the nondestructive discrimination capabilities of TXRF and SR-XRF measurements for the samples were found to be 85.7% and 100%, respectively. Therefore, we propose a combination of TXRF and SR-XRF as a new nondestructive single fiber identification method for forensic science. Moreover, if partial destruction of a single fiber is allowed, the observation of the cross section and micro-Fourier-transform infrared spectroscopy measurements is useful for identifying red silk fibers.

Cotton can be coloured by dyeing and printing using either dye or pigment colourants. Pigments are insoluble in water but can be dispersed in a polymer print binder and heat-fixed to the fabric. Vat and sulphur dyes similarly have low solubility in water but through alkali/reduction can be solubilised and exhausted onto the cotton fibre. Following their reoxidation, the dyes are insolubilised in the fibre and, like pigment prints, in general exhibit good wash fastness. In this study, sequential acid/alkali/peroxide or acid/dithionite/peroxide treatments were investigated as a means of removing pigment/polymer prints and common sulphur and vat dyes from coloured cotton fabric. Using the sequential acid/dithionite/peroxide treatment, up to 97% of both sulphur and vat colourants could be “stripped” from dyed cotton producing a white cellulosic feedstock material that could be used for “new” fibre regeneration. By contrast, the “stripping” of the pigment/polymer binder colourant system was less predictable and less complete and is probably a reflection of the different chemical natures of the polymer binder and pigments. This contrasting behaviour highlights the range of chemistries applied to cotton and that developing a universal single treatment to strip out all finishes may be problematic.

Chinese herbal medicine is an ancient part of humanity's heritage. However, the quality of commercial Chinese herbal remedies is currently compromised by illegal dyeing and adulteration. A rapid screening method of suspected dyeing compounds based on surface-enhanced Raman scattering (SERS) has proven difficult to develop due to the extreme complexity of the extraction of traditional Chinese medicinal products, as well as the lack of selective signal enhancement for target adulterants on commercially available Ag or Au substrates. Defective Cu2O nanostructures provide specific anchoring sites for dye adulterants such as Sudan red dyes on the basis of coordination between hydroxyl/azo groups and exposed Cu sites. This coordination facilitates an effective analyte-substrate charge-transfer, resulting in a prominent Raman signal enhancement for the analyte. Based on the mechanism of selective signal enhancement on Cu2O, this study shows that the adulterant Sudan red III in the extractions of various herbal medicines can be detected directly even at an extremely low concentration of 0.3 mg/kg. The findings suggest the advantages of semiconducting materials as promising SERS substrates for practical applications.

Background Sensory and structural characteristics of hair can be modified by chemical and physical treatments, as dyeing, brushing, but also by external factors, as sunlight radiation. However, quantitative data relating damage to the degree of hair curliness and treatments are missing. Objective To evaluate the effect of chemical and physical treatments on different types of hair. Methods In this study, we compared the effects of bleaching/dyeing, thioglycolate-based straightening, brushing/flat iron and UVA/Vis radiation on different types of hair: Caucasian (straight dark brown, straight blond, wavy dark brown and curly dark brown) and Afro-ethnic hair. Results Bleaching/dyeing and UVA/Vis radiation increased combing work of Afro-ethnic hair tresses, indicating damage to the cuticle scales, which was confirmed by SEM images. Further, bleaching/dyeing caused wear on cuticles with high protein loss and reduction on the tryptophan content, independently of the hair curliness, which characterizes those procedures as very aggressive to hair structure. Straightening using ammonium thioglycolate, due to the oxidative treatment evolved, caused significant colour fading in brown/black tresses, while UVA/Vis radiation affected the colour of only blond hair tresses since they are poor in eumelanin, the photoprotective and photostable melanin molecule. Conclusion The combination of analytical and image techniques contributed to understanding how the hair shape is related to the type of damage caused by several chemical and physical treatments. These findings contribute to the development of safety cosmetics that insure the beauty of curly hair, both Caucasian and Afro-ethnic hair.

John Mercer (1791–1866) was a pioneering textile and colour chemist with a legacy of achievements. His invention of mercerising that bears his name, treating cellulosics with sodium hydroxide to bring about advantageous changes in fibre and fabric properties, will stand for all time as one of the most important textile chemical treatments ever developed. However, Mercer's contributions to the textiles and coloration industries went far beyond mercerisation. A self‐taught chemical experimentalist par excellence, his keen observations and interest in calico printing led to many novel developments, such as his work on Chrome Yellow and other ‘mineral colours’. Mercer developed new methods for fixing Prussian Blue on calico and wool, developed new mordants for dyeing, improved the extraction of carminic acid from cochineal, and improved the oiling process in Turkey Red dyeing. He saved lives with his research into early antimicrobials, preventing the spread of cholera in textile villages in Lancashire. Mercer was an unsung hero of early photography, and developed light‐sensitive imaging materials and made some of the earliest recorded monochromatic colour photographs. His forward‐looking views on technical education, that workers in the industry should be fully instructed in the nature of the various substances used in their arts, later came to fruition in the establishment of the textile departments in Manchester, Leeds and Glasgow. To this day, Mercer remains the only textile chemist who has ever been elected as a Fellow of the Royal Society since 1852. He is thus quite rightly considered as the Father of Textile Chemistry.