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Recently, natural dyes are being explored all over the world as safer and highly sustainable bio-based alternatives to synthetic dyes. Agricultural wastes and plant by-products are the most commonly explored alternatives with dual benefits of waste reclamation and sustainable dye production with extra value-adds. Hypercium scabrum plant contains interesting bio-dye molecules with high flavonoids and tannin contents. The present study aims at exploring the potential of H. scabrum plant extract to color wool textiles with a focus on sustainable bio-dye production and fastness properties. The extracted bio-dye was quantitatively (for total phenolic (2.733 mg per CE/g) and total flavonoid (1.140 mg per GAE/g) content using the Folin–Ciocalteu method) and qualitatively (UV–Vis, FT-IR, and EDX) characterized. The effect of dyeing parameters like pH (2–8), temperature (60–90 °C), dry-weight content of plant material as a dye (25–150% o.w.f.), and dyeing time (15–120 min) on color strength (K/S) values were assessed. Color fastness assays showed good resistance to light, washing, and rubbing. The effect of artificial aging (Xenon arc lamp) on the color strength of dyed wool yarns under different exposure times (0–48 h) was explored. The highest color fading occurred in control dyed samples with a first-order rate constant of 131.57 h−1 and a half-life period of 5.26 x 10−3 h. Color difference (ΔE) values suggested that mordanted samples showed less fading compared to control dyed samples at equal times of Xenon exposure. Additionally, the dyed samples were washed in double distilled water, tap water, and 4 g/L NaCl solution to check their effects on the corresponding K/S values while 4 g/L NaCl solution mimics the real conditions of perspiration. Maximum color leaching occurred in 4 g/L NaCl washing with a first-order rate constant of 11.57 min−1. Cost analysis of the dye extraction and dyeing procedure revealed that the process is sustainable and economical. Thus, the use of H. scabrum whole plant can provide a clean, economical, and sustainable source of alternative natural dyes that can be used to substitute synthetic analogs.

In this study, we explore the dyeing properties of the extract of sappan wood natural dye for coloration of wool yarn to find the potential use of natural dyed wool yarn in the development of eco-friendly textiles. Different characterizations were used to know the chemistry of sappan wood dye and its interaction with metal salts and wool. Interestingly, we found that metal salts, which are called as mordants in reference to unmordanted dyed sample, play an important role in fixing the dye molecule on wool as well as in creating different shades with a variety of hues and tones. The typical color of fabric dyed with extracts of sappan wood without mordant varies from yellowish to red. Light yellowish shades were obtained in case of aluminum sulfate-mordanted samples, whereas yellowish shades were obtained in case of ferrous sulfate mordant. Light colorfastness of the premordanted dyed samples was relatively better than that of the unmordanted dyed samples. The wash fastness of all samples mordanted as well as unmordanted shows color change fairly good to good level, whereas the color staining on wool and cotton was found to be negligible.

Prangos ferulacea (Jashir) plant possesses various phytoconstituents such as coumarins, flavonoids, alkaloids, umbelliferon, and monoterpenes and has been used in traditional medicine. The presence of flavonoids in aerial parts of Prangos ferulacea necessities further examination of using them as a source of natural colorants for developing natural and beautiful shades on wool yarns. This will add one more new effective natural dye source and ease the dependency of the present-day textile industry on synthetic colorants. Simple adsorption of aqueous dye extract on the wool followed by evaluation of buildup properties using 28 different binary metal combinations as mordants were studied in this study. The dyeing was performed by exhaust dyeing method and dyed samples were analyzed through reflectance spectroscopy and analyzed in terms of color strength, CIEL*a*b*, and CIEL*c*ho values. Color characteristics were evaluated on a spectrophotometer under D65 illuminant and 10° standard observer. FT-IR and SEM analyses were performed to characterize P. ferulacea dyed wool yarns. The results showed that overall 29 different shades having very good to excellent fastness properties were produced by the use of different metallic salt combinations in natural dyeing of wool yarns using aerial parts of P. ferulacea as a source of natural dye.

Terminalia arjuna(Roxb.) Wight and Arn. (family: Combretaceae) is a large evergreen cardioactive plant drug available throughout India. The bark of T. arjuna is medicinally used as a tonic and is chemically characterized by the presence of tannins and related compounds with 20.0–24.0% tannin content. This research study investigates the use of barks of T. arjuna for the extraction of color components to develop natural and beautiful shades on wool with different hues and tones using binary and ternary metal salt combinations (aluminum potassium sulfate, ferrous sulfate, and stannous chloride). The dyeing was carried by exhaustion method and dyed samples were analyzed using a reflective spectrophotometer in terms of CIELAB (L*, a*, and b*) and color strength (K/S) values. Wash and light fastnesses were investigated according to (International Organization for Standardization)ISO standards. pH has marked effect on the K/S values of dyed woolen yarn. The results showed that overall 54 different shades having good to very good fastness properties were produced by control dyeing (un-mordanted) and the use of different metallic salt combinations in dyeing of wool using T. arjuna bark extract as a source of natural dye.

Acacia nilotica an important medicinal plant of topical and sub-tropical regions belonging to family Fabaceae of genus Acacia is a source of many active phytochemicals (secondary metabolites) have been explored to study their useful utilization in different fields. The versatile utility of this plant as a source of timber, a source of fodder, tannin, and gum, and fuel has prompted researchers to deepen investigations for full utilization of this plant. To exploit its use as a colorant for textiles, this research study investigates for the first time pre-mordanting of wool with binary and ternary metal salt combinations using aluminum potassium sulfate, ferrous sulfate, and stannous chloride mordants in order to develop natural and beautiful shades on wool with different hue and tone. The dyeing was carried by exhaustion method and dyed samples were analyzed using a reflective spectrophotometer in terms of CIELab and CIELch (L*, a*, b*, c*, and h°) and K/S values. Wash and light fastnesses were investigated according to ISO standards. Wool samples pre-mordanted with ferrous sulfate-stannous chloride (neutral medium) displayed the highest color strength value of 11.22 followed by ferrous sulfate-alum and alum-stannous chloride combinations. Statistical analysis of color parameters confirms the synergetic role of individual metal salts in different combinations. The results showed that 36 different shades having good to very good fastness properties were produced by the use of different metallic salt combinations in the natural dyeing of wool using A. nilotica bark extract as dye.

High susceptibility of wool toward bacterial growth owing to proteinous nature and moisture retention ability leads to need for antibacterial functionalization of wool to cure the resulting deterioration. Antibacterial colored wool was designed via application of Terminalia chebula, Alkanna tinctoria, and Tagetes erecta natural dyes. Characteristics in terms of color and antibacterial activity were compared to correlate coloring compound’s effect on characteristics of dyes and, both T. chebula and A. tinctoria dyes inferred themselves actively resisting bacterial growth while T. erecta was not efficient against bacterial strains. Colorful shades of good color and fastness properties were obtained from selected natural dyes on woolen yarn. Results show Bacillus subtilis and Staphylococcus aureus (gram positive) were highly resisted by the effect of T. chebula and A. tinctoria dyes, and T. chebula among them proved best in terms of both color characteristics and antibacterial potential.

In spite of the widespread study on anticancer delivery systems, various difficulties still persist on how to produce a suitable vehicle or carrier that can deliver anticancer agents to particular positions in the human body to aim cancerous tissues or cells and consequently treat cancer. Such complications might be related with little effectiveness produced by the high toxicity, unstable carrier and by the presence of numerous intracellular blockades like endosome entrapment, lysosomal enzymatic degradation, nuclear membrane, plasma membrane etc. Pullulan nanoparticles conjugated with various anticancer agents have been designed and developed to achieve receptor-mediated endocytosis in tumor tissues/cells and to deliver anticancer agents at the intracellular compartments. Within this area, this review article highlights the recent research on pullulan based nanoparticle formulations demonstrating its flexibility and relevance in biomaterials science to design anticancer approaches. Pullulan nanoparticles generate minimum side effects than systemic chemotherapy and attain sustained/prolonged delivery of an anticancer drug at cancer sites. Pullulan nanoparticles are highly beneficial because of their receptiveness toward exogenous as well as endogenous stimuli like bioresponsiveness, pH gradients, temperature, photoresponsiveness and so on. Here, we summarize the different pullulan derivative nanoparticles for tumor therapy and their delivery related systems, discuss the strategy approaches for cytotoxicity and review the research concerning pullulan nanoparticles reported in the literature.

Associated environmental hazards with the use of synthetic dyes and toxic metal mordants in the textile industry lead to concerns for alternatives. Natural dyes and biomordants are the new eco-friendly and biocompatible resources for textile coloration obtained from never-ending natural flora. The coloration potential of naphthoquinone-based colorants from Alkanna tinctoria roots on wool was investigated in this study with the application of both metallic mordants as well as biomordants. Color characteristics were evaluated on a spectrophotometer under the D65 illuminant, 10° standard observer, and fastness properties by using standard methods. A wide range of shades was obtained with good color characteristics and fastness results. Iron among metallic mordants, pomegranate peel extract (PPE) and babool among biomordants increased the color yield of dyed wool. Scanning electron microscopy (SEM) confirmed the undamaged physical structure and surface morphology of dyed wool.

The searches for new sources of natural dyes have been recently increased in many countries. This article is aimed to explore the dyeing potential of Cassia fistula as a source of natural dye on wool. In this study, the anthraquinone colorants are extracted from fruit of Cassia fistula by aqueous extraction method. Mordanting and subsequent dyeing of wool with extracted colorants were then performed to study the colorimetric and fastness properties. Three metallic salts aluminum sulfate, ferrous sulfate, stannous chloride and their combinations were used in this study to fix and increase the color as well as fastness properties of the substrate. UV visible and Fourier transform infrared spectroscopy (FTIR) analysis show identification of functional groups in the dye molecule. Colorimetric properties were analyzed by reflectance spectrometry in terms of L*, a*, b*, c*, h○ and K/S values. Color fastness was investigated in terms of light, wash and rub (dry/wet) tests. Results demonstrate that novel and fashionable brown shades with different hue and tone were obtained. Therefore, Cassia fistula has an exciting opportunity to be used as a source of natural dye in textile coloration.

Coloration of textiles with natural dyes involves huge consumption of chemicals; mainly, metal salt mordants, which pose serious environmental challenges. To mitigate this pollution, more and more environmentally friendly, biodegradable, biocompatible and renewable products should be popularized in dyeing industry. This paper proposes a sustainable and metal salt-free dyeing of wool samples by employing natural mordants extracted from pomegranate peel (Punica granatum L), gallnut (Quercus infectoria L) and catechu (Acacia catechu). The color parameters of dyed wool samples were greatly found to be dependent on the chemical compounds present in respective biomordants and their interaction ability with the functional groups of wool and the dye molecules. The investigated biomordants exhibit different interactions with coloring compounds of Butea monosperma (palas) dye resulting in deep brown, olive green, dark brown, cinnamon, burgundy, and yellowish hues on wool. All the biomordants selected in this study improved dye performance and resulted in a broad beautiful spectrum of colors with acceptable fastness properties. The results encourage the search and exploitation of new plant species as a source of biomordants to replace metallic and toxic mordants currently used in textile industry.

In this work, we investigated the use of pomegranate peel extract as an effective functional dye for producing beautiful natural shades on wool and to impart durable antimicrobial properties. Wool is treated with various metal salt mordants in the presence of pomegranate dye under optimum natural dyeing conditions. The structural changes of wool are characterized by SEM and FT-IR techniques. The properties of color strength, color fastness to light, washing, rubbing, and durability of antimicrobial activity to washing are investigated. The experimental results indicate that there is small color variation among shades obtained under identical dyeing conditions. Furthermore, it was found that metal salt mordants improved dyeing depth, fastness properties, and effectively enhanced the durability of antimicrobial activity up to several washing cycles.

This study was undertaken to propose an alternative use of Acacia nilotica bark extract as a potential source of biomordant for the development of ecofriendly shades of varying hue and tone in conjunction with Kerria lacca (Lac) and Rheum emodi (Himalayan rhubarb) natural dyes. The colorimetric analysis of K. lacca and R. emodi natural dyes were evaluated onto the woolen yarn samples adopting pre-mordanting technique using 1.0–5.0% (o.w.f.) A. nilotica as biomordant. The hue of color developed was found to be in yellow-red coordinate of color space diagram with hues shifted toward red region for K. lacca and toward yellow region for R. emodi dyed samples. The color strength (K/S) values were found to increase with increase in the concentration of biomordant and were found highest for 5.0% (o.w.f.) A. nilotica mordanted samples. Color fastness with respect to light exposure, washing, rubbing for the developed shades ranged between good to very good ratings of 4–5 on grey scale, confirming the possibility of using A. nilotica bark extract as a potential source of biomordant for enhancing the colorimetric and fastness characteristics of dyed woolen yarn samples.

Mordanting methods effect on color characteristics and fastness properties, particularly light fastness were evaluated in this study. Effect of metal mordants and their combinations on wool dyeing with Terminalia chebula natural dye were investigated and correlation between dye structures, effect of metal mordant and mordanting methods were established. Results reveal that T. chebula can be used as yellow dye with or without metal mordants to get a variable range of shades on wool with good color strength and fastness properties, and appreciable shade variations with mordanting methods observed. Color performances of dyed substrate indicated substantial improvement in depth of shades and color fastness in case of mordanted samples. Pre-mordanting with tin and post-mordanting with alum proved to be most effective for increasing K/S values of the dyed substrate under the optimum dyeing conditions.

This study was undertaken to propose an alternative use of Adhatoda vasica leaves extract as a potential source of natural dye for the coloration of woolen yarn/fibers. Premordanting technique was adopted with double metal salt combinations of ferrous sulfate, stannous chloride, and potassium aluminum sulfate and double biomordant combinations of gallnut, pomegranate, and babool, to achieve dyed textile materials of acceptable colorimetric and fastness properties. Sixty-three sober and elegant shades were developed on wool by varying the nature and the concentration of mordants involved in the combinations. The hue of color developed was found to be in yellow-red coordinate of color space diagram. All the dyed samples presented excellent color strength (K/S) values and highest values were found in case of gallnut + pomegranate peel extract (PPE) combination. Biomordants produced altogether different behavior in comparison to metal mordants in the development of ecofriendly shades of different hue and tune. Majority of the dyed samples showed excellent fastness properties with respect to light, washing, and rubbing which confirmed the possibility of using A. vasica leaves extract as an effective yellow natural dye.

Annatto colorants derived from Bixa orellana L. seeds have been extensively used in a wide range of food commodities such as dairy products, flour confectionery, fish, soft drinks, meat products, snack foods, and dry mixes. To exploit its use as a colorant for textiles, this research study investigates for the first time pre-mordanting of wool with bi and tri metal salt combinations using aluminum potassium sulfate, ferrous sulfate, and stannous chloride mordants in order to develop natural and beautiful shades on wool with variation in hue and tone. The dyeing was carried by exhaustion method and dyed samples were analyzed using a Reflective Spectrophotometer in terms of CIELAB (L*, a*and b*) and K/S values and washing and light fastnesses were investigated according to I.S.O. standard recommendations. In the dyeing experiments, wool samples pre-mordanted with Fe + Sn displayed highest color strength followed by Fe + Al and Al + Sn combinations. The results showed that overall 36 different shades having good to very good fastness properties were produced by the use of different metallic salt combinations in the natural dyeing of wool using annatto dye.

The present article focuses on the effect of different combinations of metal mordants on color characteristics and fastness properties of natural dye extracted from Juglan regia L bark powder. The influence of different types of mordant combinations such as alum + ferrous sulphate, alum + stannous chloride, ferrous sulphate + stannous chloride, and alum + ferrous sulphate + stannous chloride on color parameters has been investigated in terms of CIELab (L*, a*, b*, c*, and h°) and K/S values. The fastness properties with respect to light, washing, and crocking of developed shades were determined according to ISO and AATCC test methods. Based on the experimental results, it has been found that 96 shades with novel and fashionable hues were produced by the use of these metal salt combinations. It was also found that all mordanted samples had satisfactory light and wash fastness ratings. Dry rub fastness was found relatively better than wet rub fastness.

This study was undertaken to propose alternative use for teak leaves, a timber industry byproduct, as potential dyeing source for wool fibers. The coloring potential of anthraquinone colorants from teak leaves were studied on wool with pre-mordanting method using double and triple mix metal salt combinations (ferrous sulphate, stannous chloride and potassium aluminum sulphate) as mordants. Thirty-six sober and elegant shades were developed on wool by varying the type of metal involved in combination as well as concentration of the dye. The hue of color developed ranged from light orange—brown to dark brown. The color strength (K/S) has been found to be very good in dyed woolen yarn samples and particularly was highest for iron + alum combination. Color fastness with respect to light exposure washing, rubbing for the developed shades ranged between good to very good, which confirmed the possibility of using waste leaves of Tectona grandis as a source of effective brown natural dye.