- Email: [email protected]
Cotton knitted fabric using brewer’s yeast suspension
Alexandria Engineering Journal (2019) 58, 819–825
H O S T E D BY
Alexandria University
Alexandria Engineering Journal www.elsevier.com/locate/aej www.sciencedirect.com
ORIGINAL ARTICLE
Part I: Enzymatic treatment of Bamboo, Bamboo/Cotton knitted fabric using brewer’s yeast suspension Hala Shawky El-Khatib a, Alaa Arafa Badr b,*, Walaa Ali Diyab c, Rasha Mohammed Atia c a
Textile Printing, Dyeing & Finishing Dept., Faculty of Applied Arts, Helwan University, Giza 11795, Egypt Textile Engineering Department, Faculty of Engineering, Alexandria University, Alexandria 21544, Egypt c The Clothing and Textile Department, Faculty of Home Economics, Al-Azhar University, Tanta 31732, Egypt b
Received 18 December 2017; revised 29 March 2019; accepted 12 May 2019 Available online 30 July 2019
KEYWORDS Amylase; Bamboo; Brewer’s yeast; Enzymatic treatment; Lipase; Protease enzyme
Abstract In this paper, the optimization of the bio-treatment of bamboo and bamboo/cotton knitted fabrics using brewer’s yeast suspension has been accomplished. After enzymatic treatment, the dyeing operation by using Brazilwood natural type was applied. This comprehensive paper is focused on studying the factors that could influence the bio-treatment like concentration of enzyme, pH value of the bio-treatment bath, temperature and duration of treatment to set the best conditions of the treatment process. The influence of changing these factors on fabric colour strength and wettability was investigated. Scanning Electronic Microscope (SEM) analysis was performed for bamboo and bamboo/cotton samples after pre-treatment and enzymatic hydrolysis of bamboo, in order to have a better understanding of the morphology. This microscopic inspection was carried out to inspect the surface features of the fabrics. Results have shown that the growing in colour strength caused by the bio-treatment with enzymes is referred to the enzyme extract which includes primarily lipase, amylase and protease enzymes that develop the fabric dyeability. Furthermore, the wettability was improved by applying enzymatic treatment, where the diffusion rate of the natural dye is increased for the bamboo and bamboo/cotton fabrics. Ó 2019 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).
1. Introduction Bamboo is a natural material consisting of cellulose fibres embedded in a lignin matrix. It is an environmentally friendly * Corresponding author. E-mail address: [email protected] (A.A. Badr). Peer review under responsibility of Faculty of Engineering, Alexandria University.
product [1]. Bamboo fabric has outstanding wicking characteristics and is very soft and can be worn directly next to the skin [2]. It is well known that these fibers provide excellent performance to textile items, such as antibacterial, antifungal, UV protection, IR absorption and good water absorption properties [3]. Recently, many studies of enzyme applications on textiles have been reported. Some researchers studied cellulase
https://doi.org/10.1016/j.aej.2019.05.017 1110-0168 Ó 2019 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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hydrolysis of cellulosic materials and the textile properties of cotton fabrics subjected to cellulase treatment. In addition, other studies reported bio-polishing of cotton fabrics, which diminishes pill formation and improves fabric hand. Furthermore, Jin [4] investigated that enzyme applications for scouring cotton fabrics reduced impacts on the environment through cutting down energy cost and waste water pollutants using biochemical reactions under mild conditions. Enzymes like proteases and carbohydrases are being applied technically for a long time and occupy the main section of the worldwide enzyme market. Lipases made from different yeasts [5]. Now, it occupies less than 5% of the market. Besides, it stimulates an extensive range of reactions, where it catalyzes the breakdown of fatty acid ester bond inside the triacylglycerol (TAG) and releases free fatty acids. Therefore, in this research paper, an enzymatic treatment was applied to extract non-cellulosic materials from regenerated bamboo fibers. This work was focused on applied bio-treatment or enzymatic treatment on bamboo and bamboo/cotton knitted fabrics using brewer’s yeast suspension, which contains a mixture of many enzymes (amylase, lipase and protease).
Bamboo fibers properties.
Table 2 Fiber type
Fiber length
Fiber Fineness
Bamboo
38 mm
1.6 dtex
Yeast has been supplied by the Egyptian Starch, Yeast and Detergents Company, Egypt. 2.5. Chemicals and auxiliaries Sodium carbonate and acetic acid have been provided from Morgan Chemical Industries Company, Egypt. Mordant has been supplied from Alum (Aluminum Sulfate) Morgan Chemical Industries Company, Egypt. Nonionic detergent has been provided from (Chromatech 3QJ) Chromatech LTD, England. 3. Methods 3.1. Preparation of enzyme suspension
2. Materials 2.1. Yarns In this paper, 30/1, 70% bamboo/30% cotton and 100% bamboo yarns were determined to knit fabrics with normal single jersey structure. The characteristics of the Egyptian cotton fibers ‘‘Giza 88” utilized in the paper are exhibited in Table 1. Moreover, the Bamboo fibers properties are shown in Table 2. 2.2. Fabric manufacture The Santoni circular knitting machine was used to knit the two single jersey samples in KABO Company, Alexandria City, Egypt. The machine specification was: Santoni ‘‘Italy”, 24 gauge, 18 in. diameter, 54 feeders and total needles numbers 1356. The fabric loop length was kept the same at 2.8 mm for all feeders for the all knitted fabrics. Furthermore, the yarn knitting tension was set at a value 5 CN for all machine feeders. The specifications of the knitted fabric samples are cleared in Table 3.
3.2. Pretreatment of Bamboo and Bamboo/Cotton knitted samples The two fabric samples were bio-treated with a suspension of filtrated brewer’s yeast at various concentrations ranging from without to 100 mL. This was achieved according to the volume of the treatment bath at 1:50 liquor ratio. The treatment process was carried out at different pH values from 5 to 9, for different durations ranging from 15 to 120 min and at temperatures ranging from 40 °C to 80 °C. Lastly, the pretreated fabrics were soaped using non-ionic detergent 2 g/l at a temperature 70 °C for a quarter hour and afterwards rinsed using cold water. 3.3. Dyeing of Bamboo and Bamboo/Cotton knitted fabrics with natural dye
2.3. Natural dye Brazilwood natural dye utilized in this research has been purchased in powder form from Toblamas Co. USA and is considered as a profit-oriented product. 2.4. Enzymes Fungi saccharomyces cerevisiae and saccharomyces uvarum were applied in this paper as a suspension of brewer’s yeast. Table 1
This was achieved by pasting the brewer’s through adding an amount of sugar (100 g of sugar to 126 g of dry basis). Thereafter, water was added to the yeast paste accompanying with good stirring for completing a one liter of a whole volume. Lastly, the solution was filtrated and frozen.
The dyeing exhaust method was applied through laboratorybeaker dyeing machine - Rapide - China. The pretreated bamboo and bamboo/cotton knitted fabrics were pre-mordanting using 7 g/l alum mordant at pH 6 for 30 min at the room temperature. Thereafter, in a separate bath, the dyeing stage was accomplished by using the 7% extracted Brazilwood natural dye which contains 20% sodium chloride and 1 g/l dispersing agent at 40 °C, pH 7 for 60 min time.
Cotton fibers properties.
Cotton Giza 88
Length
Uniformity %
Strength
Elongation %
MIC
Rd
+b
Trash Count
Maturity %
35.5
87.3
41.5
3.57
3.95
67
10.6
33
87
Part I: Enzymatic treatment of Bamboo Table 3
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Specification and properties of the knitted samples.
Fabric material
Courses/cm
Wales/cm
Fabric Weight g/m2
Thickness ‘‘mm”
100% Bamboo %70 bamboo %30 cotton
22.5 24.3
15.6 17
153.5 175
0.4365 0.4638
After dyeing process, the fabrics were rinsed using cold water and soaped with 2 g/l nonionic detergent at 70 °C for a quarter hour. 4. Fabric testing 4.1. Colour measurements Datacolor Spectrophotometer was applied to measure the colour strength of all fabric samples. Where, the K/S was evaluated by using the following Kubelka Munk equation [6]: K=S ¼ ð1 RÞ2 =2R where, K = Constant related to fabric light absorption S = Constant related to fabric light scattering R = Dyed fabric reflectance at a wave length measured at maximum light absorption. 4.2. Determination of the fabric wettability The aim of the test is to evaluate the impact of the enzymatic treatment on the absorption merit of bamboo and bamboo/cotton blend knitted fabrics. Wettability was evaluated with AATCC standard number 79-1986, through putting a water drop above the surface of the fabric and then recording the consumed time period until the drop disappeared.
After enzymatic treatment, the pre-mordanting with alum and dyeing with 7% Brazilwood natural dye were applied as mentioned above. The color strength (K/S) values of the fabric samples were recorded at spectrophotometer and plotted in Fig. 1. From this figure, it can be observed that increasing enzyme concentration leads to an increase in color strength until reaching its darker color at the higher concentration. The enzymes that contained in the brewer’s yeast (protease, amylase, and lipase) are heightening dye absorption for the samples [7]. The enzyme has a great impact where it gives a better dye diffusion inside the fabric and as a result increases dye uptake merits. In general, bamboo fibers are consisting of various materials with different percentages containing hemicellulose, cellulose, lignin and also pectin [8]. Subsequently, to extract non-cellulosic materials from natural bamboo fibers, the enzymatic treatment was performed. Natural bamboo fibers exist morphologically as individual fibers, cemented together by noncellulosic substances (lignin, hemicellulose, pectin, and so on). The mechanical and chemical treatments were applied in order to: convert the bamboo strips into fibers ‘‘fiberized” firstly and to disconnect fiber bundles for improving the penetration of enzymes solution inside the fibers [9]. An improvement in water wettability and strength retention characteristics of cotton was obtained through the treatments with pectinase, lipase, and protease used separately [10]. These enzyme treatments eliminate non-cellulosic substances, leading to a hydrophilic surface and a developed wettability [10].
4.3. Scanning Electronic Microscope (SEM) analysis The surface morphology of the bamboo and bamboo/cotton fabric samples has been accomplished using Scanning Electronic Microscope (SEM), where small specimens of fabrics samples and control fabric were firstly covered with gold inside a vacuum coating unit and then put under the SEM at the same magnification level. 5. Results and discussion 5.1. Factors affecting on the enzymatic treatment of Bamboo, Bamboo/Cotton knitted fabrics 5.1.1. Brewer’s yeast suspension concentration The bamboo and bamboo/cotton knitted fabrics were treated with brewer’s yeast including many enzymes (protease-lipase-amylase) and with applying different concentrations ranging from without, 25% to 100%. After adjusting the pH at 7 and the L:R at 1:50, the fabrics were processed inside the bath at 70 °C for 30 min, and finally the fabrics were rinsed with cold water and hot water for approximately 15 min.
Fig. 1 Relation between concentration % of brewer’s yeast suspension and the colour strength values (K/S) of 100% bamboo and bamboo/cotton blend dyed knitted fabrics. Bio-treatment condition: X enzymes conc., pH 7, 30 min., temp. 60 °C for Bamboo/Cotton and 70 °C for Bamboo, L: R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/Cotton, pH 6, 30 min., at room temp. L: R 1:50. Dyeing condition: 7% Brazilwood dye, 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent, PH 7, 60 min, temp.40°c, L:R 1:50.
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Table 4, represents the efficiency of the treatment process as a function of enzyme concentration, which expressed as a percentage increase in K/S. Additionally, ANOVA analysis cleared in Tables 5 and 6 illustrated that the F-value where, there is a significant difference for every treated sample having different sample material ‘‘Bamboo and Bamboo/cotton” and for every sample material having different Brewer’s Yeast Suspension Concentration treatment respectively.
Table 5 F-value of one-way ANOVA for the effect of sample material on K/S. Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
1478.4 125.65 17.24 46.55
5.1.2. Effect of pH enzymatic treatment Since the activity of any enzyme for any substrate type depends primarily on the pH value of the medium, therefore it is essential to determine the optimum pH level of the used enzymes suspension. The knitted fabrics were subjected to enzymatic treatment at different pH levels from 6 to 9 where the other conditions were constant. Fig. 2 shows the color strength (K/S) readings of the dyed knitted fabrics. From this figure, it is shown that maximum color strength is achieved at pH 7, where, it has the optimum for this treatment. The enzyme activity is mainly relying on the pH value where, below the optimum pH, the protein is inactivated, resulting in reducing enzyme activity level [11]. The bamboo regenerated cellulosic fiber is sensitive to acid and alkali in the pretreatment [12]. Also, the ANOVA analysis confirmed that there is a significant difference for every treated sample having different sample material ‘‘Bamboo and Bamboo/cotton” and for every sample material having different pH enzymatic treatment respectively, where Tables 7 and 8 show the F-values. 5.1.3. Effect of changing temperature for the enzymatic treatment The bamboo and bamboo/cotton fabrics were treated with brewer’s yeast suspension at different temperature values inside the bath which contains 100% enzymes suspension, pH 7 for 30 min and L:R 1:50. Afterwards, the treated samples were pre-mordanted with alum mordant in a similar procedure as mentioned before; also dyeing process was carried out with the same conditions. The color strength of the dyed sample was measured and the results are exhibited in Fig. 3. From this figure, it could be shown that the temperature is the primary factor that greatly influences the K/S. Moreover, it was noticed that maximum color strength was achieved at 60 °C for bamboo/cotton and 70 °C for 100% bamboo.
Table 4
Table 6 F-value of one-way ANOVA for the effect of enzyme concentration on K/S. Bamboo Bamboo/Cotton
3424.2 5432.7
Fig. 2 Relation between pH of pre- treatment and the colour strength of 100% bamboo and bamboo/cotton blend dyed fabrics. Bio-treatment condition: 100% enzymes conc., pH X , 30 min., temp.60 °C for Bamboo/Cotton and 70 °C for Bamboo, L:R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/ Cotton, pH 6, 30 min., at room temp., L: R 1:50. Dyeing condition: 7% Brazilwood dye, 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent, PH 7, 60 min, temp.40 °C, L:R 1:50.
These results show that the maximum catalytic activity of enzymes in brewer’s yeast suspension, as well as the highest efficiency of removing the impurities from the surface of the fibers may be occurred at 60–70 °C. After this temperature, the color strength decreases due to the inactivation of the
(%) Increase in K/S as a function of enzyme concentration.
Concen. of yeast suspension
K/S of bamboo
(%) increase in K/S
K/S of bamboo/cotton
(%) increase in K/S
Without 25% 50% 75% 100%
0.73 1.96 2.76 2.86 3.17
– 168.49 278.08 291.78 361.24
1.26 1.79 2.76 2.96 3.01
– 42.06 119.05 134.92 138.89
Part I: Enzymatic treatment of Bamboo
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Table 7 F-value of one-way ANOVA for the effect of sample material on K/S.
Table 10 F-value of one-way ANOVA for the effect of sample material on K/S.
Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
259.4 63.68 13.33 89.1 42.35
Table 8 F-value of one-way ANOVA for the effect of enzyme concentration on K/S.
Table 11 F-value of one-way ANOVA for the effect of Enzyme Temperature on K/S.
Bamboo Bamboo/Cotton
Bamboo Bamboo/Cotton
481.9 211
Fig. 3 Relation between temperature of pre- treatment and the colour strength of knitted dyed 100% bamboo and bamboo/cotton blend fabrics. Bio-treatment condition: 100% enzymes conc., pH 7, 30 min., temp. X °C for Bamboo/Cotton and Bamboo, L: R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/Cotton, pH 6, 30 min., at room temp., L: R 1:50. Dyeing condition: 7% Brazilwood dye, 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent pH 7, 60 min, temp.40 °C, L:R 1:50.
enzymes. This is related to the sensitivity of the enzyme with the higher temperatures values [11]. Furthermore, the percentage growth in K/S values accompanied with enzymatic treatment temperature is obvious in Table 9. In addition, ANOVA analysis cleared in Tables 10 and 11 illustrated that the F-value where, there is a significant difference for every treated sample having different sample material and for every sample material having different temperature treatment respectively.
Table 9 fabrics. °C °C °C °C °C
2109.9 878.6
Fig. 4 Relation between pre- treatment time and colour strength (K/S) of knitted dyed 100% bamboo and bamboo/cotton blend fabrics. Bio-treatment condition: 100% enzymes conc., pH 7, X min., temp. 60 °C for Bamboo/Cotton and 70 °C for Bamboo, L: R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/Cotton, pH 6, 30 min., at room temp. L: R 1:50. Dyeing condition: 7% Brazilwood dye , 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent, PH 7, 60 min, temp.40°c, L:R 1:50.
5.1.4. Effect of enzymatic treatment time Also, the time of enzymatic pre-treatment was studied for determining the optimum time required to achieve maximum knitted fabrics dyeability. The two fabric samples were pre-treated at different durations (15, 30, 60, 90, 120 min.). The enzymatic treatment was accomplished under the same circumstances as mentioned before. Then, the treated fabrics were pre-mordanted and dyed
The influence of temperature of enzymatic pre-treatment on the dyeing performance of bamboo and bamboo/cotton knitted
Temp. of treatment 40 50 60 70 80
18 10 388.9 10,368 32.67
K/S of bamboo/cotton
(%) increase in K/S
K/S of bamboo
(%) increase in K/S
1.50 1.63 2.15 1.99 2.06
– 8.67 43.33 32.67 37.33
1.53 1.62 1.82 2.71 2.13
– 5.89 18.95 77.12 39.22
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H.S. El-Khatib et al. Table 12 F-value of one-way ANOVA for the effect of sample material on K/S. Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
55.4 60 200 53.3 36.8
Table 13 F-value of one-way ANOVA for the effect of Enzyme Time on K/S. Bamboo Bamboo/Cotton
693.1 527.7
Table 14 Wettability of (bamboo – bamboo/cotton) pretreated with brewer’s yeast filtrate. Disappearance Time of water drop on bamboo/cotton
Disappearance Time of water drop on bamboo
Concentration of Enzyme suspension
6 min
5 min
5 4 2 1
7 sec 6 sec 3 sec 1.5 sec
Without treatment 25% 50% 75% 100%
sec sec sec sec
with Brazilwood natural dye like used in the last experiments. Finally, the fabric color strength was recorded. Fig. 4 shows the relation between pre- treatment time and achieved color strength. This figure indicates that increasing the treatment time gives a little growth in the K/S reading of the dyed fabrics up to 30 min for bamboo and 60 min for bamboo/cotton. Also, from the same figure, it clears that the best enzymatic treatment was achieved at 30 min time for all fabrics. During this short time, a maximum efficiency of the enzymes was accomplished. Also, the ANOVA analysis confirmed that there is a significant difference for every treated sample having different sample material ‘‘Bamboo and Bamboo/cotton” and for every sample material having different enzymatic time respectively, where Tables 12 and 13 show the F-values. 5.1.5. Wettability of fabric samples The wettability of knitted fabrics (bamboo – bamboo/cotton) were carried out to indicate the relation between the enzymatic treatment with brewer’s yeast and its influence on the absorption properties of fabric samples and the changes in the hydrophobic/hydrophilic character of the fiber. Table 14 illustrates the relation between wettability property and enzymatic treatment by applying a different concentration of brewer’s yeast suspension. Furthermore, this table shows that the sample without enzyme treatment takes a long time (5–6 min) for the water drops disappearance and therefore it has no absorbency. After increasing the concentration of brewer’s yeast, wettability was
Fig. 5
(a) Untreated Bamboo; (b) Treated Bamboo.
developed with a little time. So, increasing of suspension concentration improves the absorbency level and as a result this reflects in removing the impurities from the surface of the fabric. Enzyme treatments effectively remove non-cellulosic substances. This results in getting a hydrophilic surface and improving fabric wettability [13]. 5.1.6. Surface morphology of knitted fabric samples The external morphology of the unfinished and finished knitted fabrics is shown better by using SEM microscope as shown in Figs. 5a, 5b, 6a and 6b. These figures demonstrate that the two knitted fabrics are relatively similar in their smoother surfaces, which reflected in removing fabrics impurities and cleaning their surfaces. Moreover, these results reveal a breakdown in the ligno-cellulosic structure of the bamboo during the enzymatic hydrolysis. The microstructural observation of the untreated, pretreated and enzymatic hydrolyzed bamboo provided a better understanding of the morphology enzymatic
Part I: Enzymatic treatment of Bamboo
825 dye is increased for the two fabric samples. Applying brewer’s yeast suspension lessens waste water and develops the dyeing merits of both regenerated bamboo and natural cotton fibers as well. The SEM images demonstrate that the two fabrics are relatively similar in their smooth surface as a result of the enzymatic treatment. Declaration of Competing Interest The authors declare no conflict of interest. Acknowledgement Authors are thankful for the cooperation and support of KABO Company (El-Nasr Clothing and Textile Company), Alexandria, Egypt for the fabrics manufacturing. References
Fig. 6 (a) Untreated Bamboo/Cotton; (b) Treated Bamboo/ Cotton.
hydrolysis stages. Also, it showed that the disorder and breakdown of the pretreated bamboo structure leading to an increase in the fabric porosity [14]. 6. Conclusion Bamboo and bamboo/cotton knitted fabric samples have been dyed by using natural dye (Brazilwood) by applying biotreatment eco-friendly brewer’s yeast suspension, consisting of three different enzymes types which are protease, lipase and also amylase. The wettability was improved by applying enzymatic treatment, where the diffusion rate of the natural
[1] K. Satindar, D.P. Chattopadhyay, V. Kaur, Dyeing of bamboo with tea as a natural dye, Res. J. Eng. Sci. 1 (4) (2012) 21–26. [2] M. Sri Vidhya, V. Bhanu Rekha, Effect of knitted bamboo structures dyed with natural colorants on ultraviolet radiation protection, J. Textile Sci. Eng. 2 (5) (2012) 1–6. [3] C. Diana, O. Simona, V. Narcisa, F. Marin, Study of RASPBERRY extract applications as textile colorant on natural fibers, Ann. Univ. Oradea, Fascicle Textiles, Leatherwork (2011) 43–46. [4] C. Jin, M. Maekawa, Evaluating an enzyme treatment of ramie fabrics, Textile Res. J. 71 (9) (2001) 779–782. [5] J. Vakhlu, Yeast lipases: enzyme purification, biochemical properties and gene, Electron. J. Biotechnol. 9 (1) (2006) 69–85. [6] P. Kubelka, F.Z. Munk, A contribution to the appearance of the paints, J. Techn. Phys. 12 (1931) 593–601. [7] H.S. El-Khatib, Dyeing of bio-treated cotton/wool blend fabric with new natural dye, in: 13th International Conference of The Faculty of Applied Arts, 2012, pp. 1–15. [8] S. Wannajun, P. Srihanam, Development of Thai textile products from bamboo fiber fabrics dyed with natural indigo, Asian J. Textile 2 (3) (2012) 44–50. [9] L. Liu, L. Cheng, L. Huang, J. Yu, Enzymatic treatment of mechanochemical modified natural bamboo fibers, Fibers Polym. 13 (5) (2012) 600–605. [10] W. Sricharussin, P. Ree-iam, W. Phanomchoeng, S. Poolperm, Effect of enzymatic treatment on the dyeing of pineapple leaf fibres with natural dyes, Sci. Asia 35 (2009) 31–36. [11] S.H. Lee, W.S. Song, Modification of polylactic acid fabric by two lipolytic enzyme hydrolysis, Text. Res. J. 83 (3) (2013) 229– 237. [12] F.W. Anik, ‘‘Bamboo as Textile Fiber”, Department of Textile Engineering, Ahsanullah University of Science & Technology (AUST), Bangladesh. http://textilelearner.blogspot.com/2013/ 07/bamboo-fiber-processing-manufacturing. html#ixzz3HIc4GW00, November, 2017. [13] W. Sricharussin et al, Effect of enzymatic treatment on the dyeing of pineapple leaf fibres with natural dyes, Sci. Asia 35 (2009) 31–36. [14] F.O. Kolawole et al, Microstructural study of pre-treated and enzymatic hydrolyzed bamboo, Leonardo Electron. J. Practices Technol. (28) (2016) 235–252.
H O S T E D BY
Alexandria University
Alexandria Engineering Journal www.elsevier.com/locate/aej www.sciencedirect.com
ORIGINAL ARTICLE
Part I: Enzymatic treatment of Bamboo, Bamboo/Cotton knitted fabric using brewer’s yeast suspension Hala Shawky El-Khatib a, Alaa Arafa Badr b,*, Walaa Ali Diyab c, Rasha Mohammed Atia c a
Textile Printing, Dyeing & Finishing Dept., Faculty of Applied Arts, Helwan University, Giza 11795, Egypt Textile Engineering Department, Faculty of Engineering, Alexandria University, Alexandria 21544, Egypt c The Clothing and Textile Department, Faculty of Home Economics, Al-Azhar University, Tanta 31732, Egypt b
Received 18 December 2017; revised 29 March 2019; accepted 12 May 2019 Available online 30 July 2019
KEYWORDS Amylase; Bamboo; Brewer’s yeast; Enzymatic treatment; Lipase; Protease enzyme
Abstract In this paper, the optimization of the bio-treatment of bamboo and bamboo/cotton knitted fabrics using brewer’s yeast suspension has been accomplished. After enzymatic treatment, the dyeing operation by using Brazilwood natural type was applied. This comprehensive paper is focused on studying the factors that could influence the bio-treatment like concentration of enzyme, pH value of the bio-treatment bath, temperature and duration of treatment to set the best conditions of the treatment process. The influence of changing these factors on fabric colour strength and wettability was investigated. Scanning Electronic Microscope (SEM) analysis was performed for bamboo and bamboo/cotton samples after pre-treatment and enzymatic hydrolysis of bamboo, in order to have a better understanding of the morphology. This microscopic inspection was carried out to inspect the surface features of the fabrics. Results have shown that the growing in colour strength caused by the bio-treatment with enzymes is referred to the enzyme extract which includes primarily lipase, amylase and protease enzymes that develop the fabric dyeability. Furthermore, the wettability was improved by applying enzymatic treatment, where the diffusion rate of the natural dye is increased for the bamboo and bamboo/cotton fabrics. Ó 2019 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).
1. Introduction Bamboo is a natural material consisting of cellulose fibres embedded in a lignin matrix. It is an environmentally friendly * Corresponding author. E-mail address: [email protected] (A.A. Badr). Peer review under responsibility of Faculty of Engineering, Alexandria University.
product [1]. Bamboo fabric has outstanding wicking characteristics and is very soft and can be worn directly next to the skin [2]. It is well known that these fibers provide excellent performance to textile items, such as antibacterial, antifungal, UV protection, IR absorption and good water absorption properties [3]. Recently, many studies of enzyme applications on textiles have been reported. Some researchers studied cellulase
https://doi.org/10.1016/j.aej.2019.05.017 1110-0168 Ó 2019 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
820
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hydrolysis of cellulosic materials and the textile properties of cotton fabrics subjected to cellulase treatment. In addition, other studies reported bio-polishing of cotton fabrics, which diminishes pill formation and improves fabric hand. Furthermore, Jin [4] investigated that enzyme applications for scouring cotton fabrics reduced impacts on the environment through cutting down energy cost and waste water pollutants using biochemical reactions under mild conditions. Enzymes like proteases and carbohydrases are being applied technically for a long time and occupy the main section of the worldwide enzyme market. Lipases made from different yeasts [5]. Now, it occupies less than 5% of the market. Besides, it stimulates an extensive range of reactions, where it catalyzes the breakdown of fatty acid ester bond inside the triacylglycerol (TAG) and releases free fatty acids. Therefore, in this research paper, an enzymatic treatment was applied to extract non-cellulosic materials from regenerated bamboo fibers. This work was focused on applied bio-treatment or enzymatic treatment on bamboo and bamboo/cotton knitted fabrics using brewer’s yeast suspension, which contains a mixture of many enzymes (amylase, lipase and protease).
Bamboo fibers properties.
Table 2 Fiber type
Fiber length
Fiber Fineness
Bamboo
38 mm
1.6 dtex
Yeast has been supplied by the Egyptian Starch, Yeast and Detergents Company, Egypt. 2.5. Chemicals and auxiliaries Sodium carbonate and acetic acid have been provided from Morgan Chemical Industries Company, Egypt. Mordant has been supplied from Alum (Aluminum Sulfate) Morgan Chemical Industries Company, Egypt. Nonionic detergent has been provided from (Chromatech 3QJ) Chromatech LTD, England. 3. Methods 3.1. Preparation of enzyme suspension
2. Materials 2.1. Yarns In this paper, 30/1, 70% bamboo/30% cotton and 100% bamboo yarns were determined to knit fabrics with normal single jersey structure. The characteristics of the Egyptian cotton fibers ‘‘Giza 88” utilized in the paper are exhibited in Table 1. Moreover, the Bamboo fibers properties are shown in Table 2. 2.2. Fabric manufacture The Santoni circular knitting machine was used to knit the two single jersey samples in KABO Company, Alexandria City, Egypt. The machine specification was: Santoni ‘‘Italy”, 24 gauge, 18 in. diameter, 54 feeders and total needles numbers 1356. The fabric loop length was kept the same at 2.8 mm for all feeders for the all knitted fabrics. Furthermore, the yarn knitting tension was set at a value 5 CN for all machine feeders. The specifications of the knitted fabric samples are cleared in Table 3.
3.2. Pretreatment of Bamboo and Bamboo/Cotton knitted samples The two fabric samples were bio-treated with a suspension of filtrated brewer’s yeast at various concentrations ranging from without to 100 mL. This was achieved according to the volume of the treatment bath at 1:50 liquor ratio. The treatment process was carried out at different pH values from 5 to 9, for different durations ranging from 15 to 120 min and at temperatures ranging from 40 °C to 80 °C. Lastly, the pretreated fabrics were soaped using non-ionic detergent 2 g/l at a temperature 70 °C for a quarter hour and afterwards rinsed using cold water. 3.3. Dyeing of Bamboo and Bamboo/Cotton knitted fabrics with natural dye
2.3. Natural dye Brazilwood natural dye utilized in this research has been purchased in powder form from Toblamas Co. USA and is considered as a profit-oriented product. 2.4. Enzymes Fungi saccharomyces cerevisiae and saccharomyces uvarum were applied in this paper as a suspension of brewer’s yeast. Table 1
This was achieved by pasting the brewer’s through adding an amount of sugar (100 g of sugar to 126 g of dry basis). Thereafter, water was added to the yeast paste accompanying with good stirring for completing a one liter of a whole volume. Lastly, the solution was filtrated and frozen.
The dyeing exhaust method was applied through laboratorybeaker dyeing machine - Rapide - China. The pretreated bamboo and bamboo/cotton knitted fabrics were pre-mordanting using 7 g/l alum mordant at pH 6 for 30 min at the room temperature. Thereafter, in a separate bath, the dyeing stage was accomplished by using the 7% extracted Brazilwood natural dye which contains 20% sodium chloride and 1 g/l dispersing agent at 40 °C, pH 7 for 60 min time.
Cotton fibers properties.
Cotton Giza 88
Length
Uniformity %
Strength
Elongation %
MIC
Rd
+b
Trash Count
Maturity %
35.5
87.3
41.5
3.57
3.95
67
10.6
33
87
Part I: Enzymatic treatment of Bamboo Table 3
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Specification and properties of the knitted samples.
Fabric material
Courses/cm
Wales/cm
Fabric Weight g/m2
Thickness ‘‘mm”
100% Bamboo %70 bamboo %30 cotton
22.5 24.3
15.6 17
153.5 175
0.4365 0.4638
After dyeing process, the fabrics were rinsed using cold water and soaped with 2 g/l nonionic detergent at 70 °C for a quarter hour. 4. Fabric testing 4.1. Colour measurements Datacolor Spectrophotometer was applied to measure the colour strength of all fabric samples. Where, the K/S was evaluated by using the following Kubelka Munk equation [6]: K=S ¼ ð1 RÞ2 =2R where, K = Constant related to fabric light absorption S = Constant related to fabric light scattering R = Dyed fabric reflectance at a wave length measured at maximum light absorption. 4.2. Determination of the fabric wettability The aim of the test is to evaluate the impact of the enzymatic treatment on the absorption merit of bamboo and bamboo/cotton blend knitted fabrics. Wettability was evaluated with AATCC standard number 79-1986, through putting a water drop above the surface of the fabric and then recording the consumed time period until the drop disappeared.
After enzymatic treatment, the pre-mordanting with alum and dyeing with 7% Brazilwood natural dye were applied as mentioned above. The color strength (K/S) values of the fabric samples were recorded at spectrophotometer and plotted in Fig. 1. From this figure, it can be observed that increasing enzyme concentration leads to an increase in color strength until reaching its darker color at the higher concentration. The enzymes that contained in the brewer’s yeast (protease, amylase, and lipase) are heightening dye absorption for the samples [7]. The enzyme has a great impact where it gives a better dye diffusion inside the fabric and as a result increases dye uptake merits. In general, bamboo fibers are consisting of various materials with different percentages containing hemicellulose, cellulose, lignin and also pectin [8]. Subsequently, to extract non-cellulosic materials from natural bamboo fibers, the enzymatic treatment was performed. Natural bamboo fibers exist morphologically as individual fibers, cemented together by noncellulosic substances (lignin, hemicellulose, pectin, and so on). The mechanical and chemical treatments were applied in order to: convert the bamboo strips into fibers ‘‘fiberized” firstly and to disconnect fiber bundles for improving the penetration of enzymes solution inside the fibers [9]. An improvement in water wettability and strength retention characteristics of cotton was obtained through the treatments with pectinase, lipase, and protease used separately [10]. These enzyme treatments eliminate non-cellulosic substances, leading to a hydrophilic surface and a developed wettability [10].
4.3. Scanning Electronic Microscope (SEM) analysis The surface morphology of the bamboo and bamboo/cotton fabric samples has been accomplished using Scanning Electronic Microscope (SEM), where small specimens of fabrics samples and control fabric were firstly covered with gold inside a vacuum coating unit and then put under the SEM at the same magnification level. 5. Results and discussion 5.1. Factors affecting on the enzymatic treatment of Bamboo, Bamboo/Cotton knitted fabrics 5.1.1. Brewer’s yeast suspension concentration The bamboo and bamboo/cotton knitted fabrics were treated with brewer’s yeast including many enzymes (protease-lipase-amylase) and with applying different concentrations ranging from without, 25% to 100%. After adjusting the pH at 7 and the L:R at 1:50, the fabrics were processed inside the bath at 70 °C for 30 min, and finally the fabrics were rinsed with cold water and hot water for approximately 15 min.
Fig. 1 Relation between concentration % of brewer’s yeast suspension and the colour strength values (K/S) of 100% bamboo and bamboo/cotton blend dyed knitted fabrics. Bio-treatment condition: X enzymes conc., pH 7, 30 min., temp. 60 °C for Bamboo/Cotton and 70 °C for Bamboo, L: R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/Cotton, pH 6, 30 min., at room temp. L: R 1:50. Dyeing condition: 7% Brazilwood dye, 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent, PH 7, 60 min, temp.40°c, L:R 1:50.
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Table 4, represents the efficiency of the treatment process as a function of enzyme concentration, which expressed as a percentage increase in K/S. Additionally, ANOVA analysis cleared in Tables 5 and 6 illustrated that the F-value where, there is a significant difference for every treated sample having different sample material ‘‘Bamboo and Bamboo/cotton” and for every sample material having different Brewer’s Yeast Suspension Concentration treatment respectively.
Table 5 F-value of one-way ANOVA for the effect of sample material on K/S. Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
1478.4 125.65 17.24 46.55
5.1.2. Effect of pH enzymatic treatment Since the activity of any enzyme for any substrate type depends primarily on the pH value of the medium, therefore it is essential to determine the optimum pH level of the used enzymes suspension. The knitted fabrics were subjected to enzymatic treatment at different pH levels from 6 to 9 where the other conditions were constant. Fig. 2 shows the color strength (K/S) readings of the dyed knitted fabrics. From this figure, it is shown that maximum color strength is achieved at pH 7, where, it has the optimum for this treatment. The enzyme activity is mainly relying on the pH value where, below the optimum pH, the protein is inactivated, resulting in reducing enzyme activity level [11]. The bamboo regenerated cellulosic fiber is sensitive to acid and alkali in the pretreatment [12]. Also, the ANOVA analysis confirmed that there is a significant difference for every treated sample having different sample material ‘‘Bamboo and Bamboo/cotton” and for every sample material having different pH enzymatic treatment respectively, where Tables 7 and 8 show the F-values. 5.1.3. Effect of changing temperature for the enzymatic treatment The bamboo and bamboo/cotton fabrics were treated with brewer’s yeast suspension at different temperature values inside the bath which contains 100% enzymes suspension, pH 7 for 30 min and L:R 1:50. Afterwards, the treated samples were pre-mordanted with alum mordant in a similar procedure as mentioned before; also dyeing process was carried out with the same conditions. The color strength of the dyed sample was measured and the results are exhibited in Fig. 3. From this figure, it could be shown that the temperature is the primary factor that greatly influences the K/S. Moreover, it was noticed that maximum color strength was achieved at 60 °C for bamboo/cotton and 70 °C for 100% bamboo.
Table 4
Table 6 F-value of one-way ANOVA for the effect of enzyme concentration on K/S. Bamboo Bamboo/Cotton
3424.2 5432.7
Fig. 2 Relation between pH of pre- treatment and the colour strength of 100% bamboo and bamboo/cotton blend dyed fabrics. Bio-treatment condition: 100% enzymes conc., pH X , 30 min., temp.60 °C for Bamboo/Cotton and 70 °C for Bamboo, L:R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/ Cotton, pH 6, 30 min., at room temp., L: R 1:50. Dyeing condition: 7% Brazilwood dye, 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent, PH 7, 60 min, temp.40 °C, L:R 1:50.
These results show that the maximum catalytic activity of enzymes in brewer’s yeast suspension, as well as the highest efficiency of removing the impurities from the surface of the fibers may be occurred at 60–70 °C. After this temperature, the color strength decreases due to the inactivation of the
(%) Increase in K/S as a function of enzyme concentration.
Concen. of yeast suspension
K/S of bamboo
(%) increase in K/S
K/S of bamboo/cotton
(%) increase in K/S
Without 25% 50% 75% 100%
0.73 1.96 2.76 2.86 3.17
– 168.49 278.08 291.78 361.24
1.26 1.79 2.76 2.96 3.01
– 42.06 119.05 134.92 138.89
Part I: Enzymatic treatment of Bamboo
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Table 7 F-value of one-way ANOVA for the effect of sample material on K/S.
Table 10 F-value of one-way ANOVA for the effect of sample material on K/S.
Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
259.4 63.68 13.33 89.1 42.35
Table 8 F-value of one-way ANOVA for the effect of enzyme concentration on K/S.
Table 11 F-value of one-way ANOVA for the effect of Enzyme Temperature on K/S.
Bamboo Bamboo/Cotton
Bamboo Bamboo/Cotton
481.9 211
Fig. 3 Relation between temperature of pre- treatment and the colour strength of knitted dyed 100% bamboo and bamboo/cotton blend fabrics. Bio-treatment condition: 100% enzymes conc., pH 7, 30 min., temp. X °C for Bamboo/Cotton and Bamboo, L: R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/Cotton, pH 6, 30 min., at room temp., L: R 1:50. Dyeing condition: 7% Brazilwood dye, 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent pH 7, 60 min, temp.40 °C, L:R 1:50.
enzymes. This is related to the sensitivity of the enzyme with the higher temperatures values [11]. Furthermore, the percentage growth in K/S values accompanied with enzymatic treatment temperature is obvious in Table 9. In addition, ANOVA analysis cleared in Tables 10 and 11 illustrated that the F-value where, there is a significant difference for every treated sample having different sample material and for every sample material having different temperature treatment respectively.
Table 9 fabrics. °C °C °C °C °C
2109.9 878.6
Fig. 4 Relation between pre- treatment time and colour strength (K/S) of knitted dyed 100% bamboo and bamboo/cotton blend fabrics. Bio-treatment condition: 100% enzymes conc., pH 7, X min., temp. 60 °C for Bamboo/Cotton and 70 °C for Bamboo, L: R 1:50. Pre-mordanting condition with alum: 7 g/l for Bamboo, Bamboo/Cotton, pH 6, 30 min., at room temp. L: R 1:50. Dyeing condition: 7% Brazilwood dye , 20 g/l Nacl, 1 g/l for bamboo and 1.5 g/l for bamboo/cotton Dispersing agent, PH 7, 60 min, temp.40°c, L:R 1:50.
5.1.4. Effect of enzymatic treatment time Also, the time of enzymatic pre-treatment was studied for determining the optimum time required to achieve maximum knitted fabrics dyeability. The two fabric samples were pre-treated at different durations (15, 30, 60, 90, 120 min.). The enzymatic treatment was accomplished under the same circumstances as mentioned before. Then, the treated fabrics were pre-mordanted and dyed
The influence of temperature of enzymatic pre-treatment on the dyeing performance of bamboo and bamboo/cotton knitted
Temp. of treatment 40 50 60 70 80
18 10 388.9 10,368 32.67
K/S of bamboo/cotton
(%) increase in K/S
K/S of bamboo
(%) increase in K/S
1.50 1.63 2.15 1.99 2.06
– 8.67 43.33 32.67 37.33
1.53 1.62 1.82 2.71 2.13
– 5.89 18.95 77.12 39.22
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H.S. El-Khatib et al. Table 12 F-value of one-way ANOVA for the effect of sample material on K/S. Without Enzymes 25% Enzymes 50% Enzymes 75% Enzymes 100% Enzymes
55.4 60 200 53.3 36.8
Table 13 F-value of one-way ANOVA for the effect of Enzyme Time on K/S. Bamboo Bamboo/Cotton
693.1 527.7
Table 14 Wettability of (bamboo – bamboo/cotton) pretreated with brewer’s yeast filtrate. Disappearance Time of water drop on bamboo/cotton
Disappearance Time of water drop on bamboo
Concentration of Enzyme suspension
6 min
5 min
5 4 2 1
7 sec 6 sec 3 sec 1.5 sec
Without treatment 25% 50% 75% 100%
sec sec sec sec
with Brazilwood natural dye like used in the last experiments. Finally, the fabric color strength was recorded. Fig. 4 shows the relation between pre- treatment time and achieved color strength. This figure indicates that increasing the treatment time gives a little growth in the K/S reading of the dyed fabrics up to 30 min for bamboo and 60 min for bamboo/cotton. Also, from the same figure, it clears that the best enzymatic treatment was achieved at 30 min time for all fabrics. During this short time, a maximum efficiency of the enzymes was accomplished. Also, the ANOVA analysis confirmed that there is a significant difference for every treated sample having different sample material ‘‘Bamboo and Bamboo/cotton” and for every sample material having different enzymatic time respectively, where Tables 12 and 13 show the F-values. 5.1.5. Wettability of fabric samples The wettability of knitted fabrics (bamboo – bamboo/cotton) were carried out to indicate the relation between the enzymatic treatment with brewer’s yeast and its influence on the absorption properties of fabric samples and the changes in the hydrophobic/hydrophilic character of the fiber. Table 14 illustrates the relation between wettability property and enzymatic treatment by applying a different concentration of brewer’s yeast suspension. Furthermore, this table shows that the sample without enzyme treatment takes a long time (5–6 min) for the water drops disappearance and therefore it has no absorbency. After increasing the concentration of brewer’s yeast, wettability was
Fig. 5
(a) Untreated Bamboo; (b) Treated Bamboo.
developed with a little time. So, increasing of suspension concentration improves the absorbency level and as a result this reflects in removing the impurities from the surface of the fabric. Enzyme treatments effectively remove non-cellulosic substances. This results in getting a hydrophilic surface and improving fabric wettability [13]. 5.1.6. Surface morphology of knitted fabric samples The external morphology of the unfinished and finished knitted fabrics is shown better by using SEM microscope as shown in Figs. 5a, 5b, 6a and 6b. These figures demonstrate that the two knitted fabrics are relatively similar in their smoother surfaces, which reflected in removing fabrics impurities and cleaning their surfaces. Moreover, these results reveal a breakdown in the ligno-cellulosic structure of the bamboo during the enzymatic hydrolysis. The microstructural observation of the untreated, pretreated and enzymatic hydrolyzed bamboo provided a better understanding of the morphology enzymatic
Part I: Enzymatic treatment of Bamboo
825 dye is increased for the two fabric samples. Applying brewer’s yeast suspension lessens waste water and develops the dyeing merits of both regenerated bamboo and natural cotton fibers as well. The SEM images demonstrate that the two fabrics are relatively similar in their smooth surface as a result of the enzymatic treatment. Declaration of Competing Interest The authors declare no conflict of interest. Acknowledgement Authors are thankful for the cooperation and support of KABO Company (El-Nasr Clothing and Textile Company), Alexandria, Egypt for the fabrics manufacturing. References
Fig. 6 (a) Untreated Bamboo/Cotton; (b) Treated Bamboo/ Cotton.
hydrolysis stages. Also, it showed that the disorder and breakdown of the pretreated bamboo structure leading to an increase in the fabric porosity [14]. 6. Conclusion Bamboo and bamboo/cotton knitted fabric samples have been dyed by using natural dye (Brazilwood) by applying biotreatment eco-friendly brewer’s yeast suspension, consisting of three different enzymes types which are protease, lipase and also amylase. The wettability was improved by applying enzymatic treatment, where the diffusion rate of the natural
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