Improving dyeability and antibacterial activity of Lawsonia inermis L on jute fabrics by chitosan pretreatment
© The Author(s). 2017
Received: 8 November 2016
Accepted: 11 December 2016
Published: 5 January 2017
This paper investigates the dyeing and antimicrobial properties of jute fiber with natural dye henna after treatment with biopolymer chitosan. The treatment was carried out by applying chitosan solution on the fiber followed by dyeing with henna dye. Then, the performance was assessed in terms of the depth of shade by measuring K/S value and colorfastness properties of chitosan-treated dyed fabric samples. It has been observed that chitosan-treated fabrics showed a higher depth of shade compared to untreated dyed samples. As far as colorfastness is concerned, the dyed samples with and without chitosan pretreatment exhibited almost similar dry rubbing fastness. However, chitosan-treated fabrics showed inferior fastness ratings for wet rubbing and washing, particularly for the fabrics with higher chitosan concentrations. Again, the experimental results demonstrated that the combination of chitosan and henna dye can significantly enhance the antibacterial activity of jute fiber against the organism Staphylococcus aureus and Klebsiella pneumoniae. These findings suggest that the application of chitosan and natural dye from henna onto jute fiber is an approach to get the desired dyeing and antibacterial property.
Jute is a natural lignocellulosic fiber which constitutes α-cellulose along with hemicellulose and lignin (Lewin 2006). This fiber is increasingly popular due to its biodegradability, high tensile strength, and better permeability (Bhuiyan et al. 2013; Ghosh et al. 2004). Therefore, the demand of naturally biodegradable and eco-friendly fibers like jute is rising gradually in recent times because of greater global ecological awareness (Wang et al. 2008).
The dyeing of jute fiber can be carried out with a wide range of synthetic dyestuffs, such as direct, vat, basic, and reactive dyes (Bhuiyan et al. 2016a). These dyes are attractive as textile colorants due to their availability, economical, brilliant shades, and excellent color fastness properties, but to some extent these synthetic dyes are allergic, carcinogenic, and detrimental to human health (Siva 2007). For this reason, there has been a revival of the growing interest on the application of non-allergic, non-toxic, and eco-friendly natural dyes on natural fibers like jute because of their high compatibility with the environment, as well as the availability of various natural coloring resources (Samanta and Agarwal 2009).
The chitosan treatment of textiles is considered as a multi-functional finish as the chemical aspects not only enhance color strength but also contribute to the microbial reduction of textile materials (Tang et al., 2016) and thus have garnered considerable interests of the researchers across the globe. The antimicrobial activity of chitosan is well-documented. It is attributed to the polycationic nature of chitosan which most likely can interact with the predominantly anionic components resulting in changes in permeability that leads to the death of cells by inducing leakage of intracellular components (Klaykruayat et al. 2010). This antibacterial characteristic leads to a considerable enhancement of microbial resistance of textile materials following treatment with chitosan.
In addition, extracts of henna leaves are capable of inhibiting the growth of both gram-positive and gram-negative bacteria. In the past, several studies (Ali et al. 2001; Bonjar 2004) have explored the antimicrobial properties of henna extracts against the microorganisms Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Proteus mirabilis. The effectiveness of henna was also observed in the management of wound infections and also against the primary invaders of burn wounds (Nayak et al. 2007; Muhammad and Muhammad 2005). However, the combined antimicrobial effect of chitosan and natural dyes on cellulosic fiber like jute has not been yet investigated. Hence, the main objectives of this study were to explore the synergic effect of chitosan and henna on microbial reduction in jute fiber followed by the analysis of dyeability and color strength of henna dye on jute fiber being treated with chitosan.
Scoured, bleached 100% plain hessian jute fabric (261 GSM) was purchased from the local market of Bangladesh and used in all the experiments. For the dyeing of jute fabric, natural dye henna (Lawsonia inermis) was brought from the local market and used to obtain the dyestuff of lawsone, which is reddish brown in color. A commercial grade water soluble chitosan (straw yellow powder, deacetylation = 95.3%) was collected from Zhengzhou Sigma Chemical Company Ltd., China, and used as received in all experiments without any physical or chemical modification. Analytical grade acetic acid (CH3COOH) from Merck, India, was used to dissolve the chitosan in water. Ethanol (C2H5OH) for the extraction of dye from henna leaves was purchased from Merck, India. Antimicrobial activity of the chitosan-treated cotton fabric was examined against the organisms S. aureus (gram-positive) and K. pneumoniae (gram-negative) were obtained from the Department of Microbiology, University of Dhaka, Bangladesh.
Treatment of jute fiber with chitosan
Test fabric sample coding
Test fabric type
Untreated and undyed fabric sample
Untreated and dyed fabric sample
0.25% chitosan-treated and dyed fabric sample
0.5% chitosan-treated and dyed fabric sample
1.0% chitosan-treated and dyed fabric sample
1.5% chitosan-treated and dyed fabric sample
Extraction of natural dye from henna
Fresh leaves of henna were dried in the sunlight for 1 day and again dried at 80 °C for 1 h in a hot air oven following washing and cleaning with distilled water. Dried leaves were grinded to powder form for getting proper extraction result. The extraction of dye was obtained after immersing 20 g henna powder in 100 mL water–ethanol mixture (90:10 v/v) for 24 h. This dye extract solution was used for the dyeing of both chitosan-treated and untreated jute fabric samples.
Dyeing with henna dyes
The dyeing of treated and untreated jute fiber was carried out using the required amount of extracts in water–ethanol mixture for 45 min at 75 °C temperature with material-to-liquor ratio 1:30 for optimum dye exhaustion. The dyeing was performed in Sandolab infrared lab dyeing machine from Copower Technology Ltd., Taiwan. After dyeing, the dyed fabric samples were rinsed with cold water and washed in a bath with 1 g/L of soaping agent at 60 °C temperature for 10 min and then dried in a dryer.
Measurement of color strength and related parameters
The values of L*, a*, and b* for a given color locate its position in the three-dimensional CIELab color space, and ∆L* = deviation of lightness; ∆a* = deviation of color in green-red axis; and ∆b* = deviation of color in yellow–blue axis. Both the color deviation and depth of shade of dyed fabric was evaluated according to AATCC test method 173-2006 in illuminant D65, large area view, and CIE 10° standard observer. Each sample was folded twice to give an opaque view, and color reflectance was measured four times at different parts of the fabric surface
Determination of color fastness properties
The fastness properties of dyed fabric samples, i.e., color fastness to washing was done according to ISO 105 C03:1989 by wash fastness tester (Gyrowash 415/8 from James H. Heal and Co., UK). The change and staining of color due to washing were assessed by comparing the untreated fabric with the treated fabric samples with respect to the ratings of color change and color staining gray scales. The evaluation of color fastness to rubbing was performed according to ISO 105 X 12: 2001 by rubbing fastness tester (Crockmeter 670 from James H. Heal and Co., UK). All the analyses of test fabric samples were conducted after conditioning the dyed fabrics in testing atmosphere (temperature 27 ± 2 °C and relative humidity 65 ± 2%) for 24 h.
The determination of specific functional groups or chemical bonds that formed between chitosan and cellulose polymer of jute fiber after dyeing with henna was carried out by Fourier transform infrared (FTIR) spectrophotometer (Cary 630) from Agilent Technologies, USA. FTIR spectra were taken by absorption mode and measured by using potassium bromide (KBr) pellets made of finely cut and ground jute fibers.
Antibacterial property testing
where A and B are the surviving cells (colony forming units per milliliter (CFU/mL)) for the flasks containing test samples (chitosan-treated and dyed jute) and the control (untreated and undyed jute), respectively, after 1 h contact time.
Results and discussion
Measurement of color strength
The better absorption of henna dye by jute fiber due to chitosan treatment has not been investigated extensively so far. However, chitosan has been proved to increase the rate of dye uptake and dye exhaustion of cellulosic fibers in case of reactive dyes (Kitkulnumchai et al. 2008; Bhuiyan et al. 2013). It may be suggested that the introduction of amino groups in the fiber structure due to chitosan treatment offers an additional affinity (Dev et al. 2009). The cationization of cellulose for the formation of ammonium ion (NH4 +) of chitosan (Bashar and Khan 2013) caused by treatment with jute fiber in acid medium may attract the acidic hydroxylated structure of the coloring component lawsone (2-hydroxy-1,4-naphthoquinone) of henna dye (Ali et al. 2009) resulting in higher absorption of dye by the fiber.
Color difference and relative color strength
The evaluation of the color parameter and the color difference of dyed fabric samples was performed by using CIELab system. The lightness value of color (from 100 to 0) is represented by L*; a higher lightness value indicates a lower color yield by the dyed fabric. Again, a* and b* values characterize the tone of the color; positive values of a* and b* stand for redder and yellower tones, while negative values show greener and bluer tones (Kuehni 2003).
Spectrophotometer characterization of chitosan-treated and untreated henna dyed jute fabric samples
Test fabric samples
Relative color strength (%)
The color difference (ΔE) values are also given in Table 2 and it is clearly demonstrated that there is a significant color difference between the untreated and chitosan-treated dyed samples. The color difference is more prominent in the case of fabric samples treated with 1.5% chitosan solution, and it decreases steadily with the reduction in chitosan concentration. The larger color difference with the increment of chitosan concentration is due to the greater absorption of dye by the fiber and accordingly leads to a higher K/S value with chitosan concentration.
Color fastness properties of dyed fabric
Color fastness to washing (color change and color staining) of untreated and chitosan-treated dyed jute fabric samples
Test fabric samples
Washing fastness ratings
Color fastness to rubbing (dry and wet) of untreated and chitosan-treated dyed jute fabric samples
Test fabric samples
Rubbing fastness (warp direction)
Rubbing fastness (weft direction)
The wash fastness ratings in Table 3 show that chitosan-treated and untreated jute fabrics dyed with henna dye have almost identical fastness ratings of “good” to “excellent” (within numerical grades 4–5) with very little variation. Again, the staining of color to adjacent multifiber fabric has been found higher for chitosan-treated dyed samples (D, E) particularly in cotton and wool fiber (3–4 and 3). Moreover, in case of dry rubbing (Table 4), all types of dyed samples have shown almost similar ratings; however, chitosan-treated samples with higher concentrations represent a lower rating (3–4) compared to untreated samples (4–5) for wet rubbing. In general, deeper shade shows inferior fastness to washing and rubbing than a lighter one on a similar type of fabric for the same dyestuff (Bhuiyan et al. 2013), because in case of deep shade, dye molecules are more saturated and tend to move out from the interior of the fiber due to washing. As discussed earlier, the chitosan present in the fabric enhances the dyesite causing higher absorption of dye resulting in a higher depth of shade. Hence, as a general consequence of achieving deeper shade, the chitosan-treated fabric samples have shown a slightly lower fastness rating in comparison to lighter, untreated fabric.
Characterization of dyed fabric samples
FTIR spectroscopic analysis
The structural properties of chitosan-treated and untreated jute fiber after dyeing with henna dyes were investigated by FTIR spectroscopy. This analytical technique provides information about the chemical bonds and molecular structure of a material. The existence of a specific chemical bond in any material is indicative of the presence of a peak at a specific wavenumber being revealed through scanning the test samples in the infrared light source.
Improvement of antimicrobial properties
The antibacterial activity of chitosan-treated and untreated dyed jute fabric samples were carried out against S. aureus (gram-positive) and K. pneumoniae (gram-negative) bacteria. The pathogenic gram-positive bacterium S. aureus is the most frequently evaluated species, commonly found in the nose, respiratory tract, and on the skin, the major cause of cross-infection in hospitals as well as in commercial and home laundry practices (Kluytmans et al. 1997). It causes skin and tissue infections, respiratory infections, and food poisoning (Weese and van Duijkeren 2010). Again, the gram-negative bacterium K. pneumonia, which is a popular test organism, is found in the normal flora of the mouth, skin, and intestines and can cause severe bacterial infections leading to pneumonia, bloodstream infections, wound infections, urinary tract infections, and meningitis (Eliopoulos et al. 2008).
Microbial reduction percentages of henna dyed jute fabrics with the increment of chitosan concentration against S. aureus (gram-positive) and K. pneumoniae (gram-negative) bacteria
Surviving cells (CFU/mL)
Surviving cells (CFU/mL)
2.55 × 105 [B]
2.80 × 105 [B]
1.32 × 105 [A]
1.94 × 105 [A]
28.0 × 103 [A]
50.0 × 103 [A]
22.0 × 103 [A]
21.0 × 103 [A]
15.0 × 103 [A]
17.0 × 103 [A]
11.0 × 103 [A]
15.0 × 103 [A]
On the other hand, fabrics dyed with henna alone without chitosan application also exhibit antimicrobial activity especially in case of S. aureus bacteria in Table 5. Moreover, the presence of residual ethanol influences the antibacterial property of henna dye due to ethanolic extraction. Several studies showed that the ethanolic extraction of L. inermis is the most active against all the bacteria in the test system compared to aqueous extraction of henna dye (Sukanya et al. 2009; Ali et al. 2001). In addition, the presence of colored pigment lawsone (2-hydroxy-1,4-naphthoquinone) is also responsible for the inherent antimicrobial activity of henna dye. The highly reactive nature of ketone groups (˃C=O) in the aromatic ring of quinones of lawsone exhibits the antimicrobial property by forming a complex irreversibly with nucleophilic amino acids in proteins and leading to inactivation of the protein and loss of function (Dev et al. 2009). Hence, the natural antimicrobial efficacy of henna dye can be enhanced considerably by coupling with chitosan for the application on textile materials to protect the clothes against common infections.
The treatment of jute fiber with the biopolymer chitosan and its effect on dyeing with natural colorants and antibacterial characteristics of fiber has been investigated. The detailed study has demonstrated the twofold effect of chitosan on jute fiber. The treatment of jute with chitosan can appreciably enhance the uptake of dye by the fiber. Moreover, the color fastness property of dyed fabrics against washing and rubbing also exhibits within the acceptable range of good to excellent. On the other hand, the antimicrobial activities of jute fabric increase significantly due to the combined effect of natural dye henna and biopolymer chitosan. Thus, the findings of the study suggest a potential application of chitosan as a non-toxic, eco-friendly, and multi-functional finish providing the desired dyeing and antimicrobial properties of jute fiber after treatment with chitosan.
MAR conceived of the study, designed the experiment and drafted the manuscript. AI and KN coordinated experimental analysis and manuscript submission. SI and AH interpreted data and drafting the manuscript. All authors read and approved the final manuscript submission.
The authors declare that they have no competing interests.
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