Wood-Rotting Fungal Pigments as Colorant Coatings on Oil-Based Textile Dyes

Abstract

Abstract:Opportunities for alternatives to synthetic textile dyes are of increasing importance as the world looks to minimize its ecological footprint. Fungal pigments within a unique class of wood-rotting ("spalting") fungi have been under investigation for several years as a possible solution, and have been shown to be ideally suited as textile dye coatings. Unfortunately, the solvent currently in use for these colorants is dichloromethane (DCM), which is an environmental problem as well as a potential human carcinogen. Recently, researchers found that the pigments from Chlorociboria species, Scytalidium cuboideum, and Scytalidium ganodermophthorum could be carried in some natural oils, which opened up a potential method of delivering pigments onto a host of substrates without utilizing DCM. Although the pigments can be carried in oil, no testing has thus far been conducted as to how oil affects the binding properties of the pigments onto textiles, or how the oil might affect the pigments directly. In this paper, the pigments produced by three well-known wood-rotting fungi were carried in raw linseed oil and applied to cotton, polyester, and nylon. Only the red pigment produced visible color change on the textiles. Cotton and polyester showed the greatest color change when the pigments were dripped onto the fabric, while polyester showed the most color when the textile was submerged into the pigment solution. Unfortunately, the colors faded significantly for all the tests except the saturation test. This indicates that while natural oils may be excellent, nontoxic alternative carriers for DCM, the pigments are not stable within them except at very high concentrations, and therefore natural oils-including raw linseed oil-are not ideal for use in conjunction with these pigments.

Fungal Pigments and Their Prospects in Different Industries

“…The literature reveals that only a handful of studies have investigated the application of fungal pigments in the textile industry, especially for dyeing different types of fabrics, such as cotton, silk, and wool. Various studies on the dyeing potential of pigments of different species of fungal genera (Monascus, Fusarium, Aspergillus, Penicillium, Talaromyces, Trichoderma, Alternaria, Curvularia, Chlorociboria, Scytalidium, Cordyceps, Acrostalagmus, Bisporomyces, Cunninghamella, Thermomyces, and Phymatotrichum) for different types of fabrics such as wool, cotton yarn, silk, polyester, and nylon have been reported [37,42,47,106,108,124,195,196,[208][209][210][211]. Studies on the dyeing potential of pigments from wood spalting fungi (red pigment from S. cuboideum, yellow pigment from S. ganodermophthorum, and green pigment C. aeruginosa) have shown the possible use of these pigments for deying bleached cotton, spun polyacrylic, spun polyamide (nylon 6.6), worsted wool, spun polyester (Dacron 54), and garment fabrics, because of their high stability and good colorfastness to washing [37,212].…”

“…Studies on the dyeing potential of pigments from wood spalting fungi (red pigment from S. cuboideum, yellow pigment from S. ganodermophthorum, and green pigment C. aeruginosa) have shown the possible use of these pigments for deying bleached cotton, spun polyacrylic, spun polyamide (nylon 6.6), worsted wool, spun polyester (Dacron 54), and garment fabrics, because of their high stability and good colorfastness to washing [37,212]. Another study has revealed that natural oils cannot be used in conjunction with these fungal pigments, as these fungal pigments are unstable in natural oils [42]. Results of all these studies have shown that these fungal pigments have good color stability, colorfastness properties, and dye uptake potential.…”

Oil-Based Fungal Pigment from Scytalidium cuboideum as a Textile Dye

“…Plates were allowed to grow for 2-3 weeks before they were dried for 24 h in a fume hood, extracted into DCM, and standardized to CIE L*a*b* values of L = 82.32, a = 26.84, and b = 13.19, as described in Robinson et al [23]. After the standardization, raw linseed oil (Sunnyside) was mixed with the pigment carried in DCM and placed on a stir plate for 48 h in order to evaporate the solvent and leave the pigment suspended in the oil, following the methodology by Palomino Agurto et al [25]. This pigmented oil was used for further testing.…”

“…These oils proved to be highly successful at carrying the fungal pigments, though not at extracting them, with raw linseed oil allowing for the highest pigment stability of those tested [24]. However, of the tested pigments, only the red pigment from S. cuboideum was found to effectively color fabric, although it showed variation in coloration based on the material to which it was applied [25].…”

Stain capacity of three fungi on two fast-growing wood

“…Existing studies have shown that the longer the incubation time of dyeing fungi is, the better the dyeing effect of wood is, but the higher the risk of white rot of wood is. Therefore, in practical application, fungal pigments can be extracted by organic solvents such as DCM and applied directly to wood dyeing, or dissolved in flaxseed oil after extraction by organic solvents and then dyeing wood, which can solve the problem of white rot of wood and shorten the whole dyeing time (Robinson et al 2014a, b;Robinson et al 2014a, b;Hinsch et al 2015;Weber et al 2015;Agurto et al 2017;Robinson et al 2017;Hinsch and Robinson 2018). In terms of zone lines, the researchers found that Bjerkandera adusta/ Trametes versicolor and Polyporus brumalis/Trametes versicolor combinations, as well as X. polymorphism, Coriolus versicolor, etc.…”