Biotechnology: An Eco-friendly Tool of Nature for Textile …
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in cotton textiles [34]. Japanese scientists submitted a patent on scoured yarns with
out-standing tensile strength retention after treating for 18 h at 40 °C cotton fibers
or their blends with proto-pectinases [2].
3.1.3 Bio-bleaching
The pure white appearance of the fabric is a fundamental requirement for the dyeing
process [35]. H 2 O 2 in alkaline pH and near to 100 °C is the most commonly applied
agent in industries for the bleaching process. The whole process of chemical bleaching demands careful control to protect any damage of fiber from radical reaction
[36]. Moreover, a huge amount of water is needed for the removal of excess peroxide for the smooth dyeing process [2]. Although, in biological processing, H 2 O 2 is
generated from C 6 H 12 O 6 in aqueous media by glucose oxidize or at controlled rates
by the combination of any detergent [37]. So this process is preferred because of its
feasibility to reuse de-sizing waste baths with minimum utilization of sources [38].
Although many processes of bleaching are based on the enzymatic generation of
H 2 O 2 is still in practice [39]. However, laccase enzymes are used as bio-bleaching
agents, attached to hydroxyl groups of phenolics to fade colored flavonoids [13].
To overcome the limitations of the bleaching process or its related concerns like
processing costs, bio-bleaching or integration of the enzymatic process is a lucrative
substitute [35]. However, more benefits like temperature reduction, duration shortening and lower doses of hydrogen peroxide can be achieved by the integration of
chemical and bio-bleaching [14].
3.1.4 Enzymatic Cleansing
Shade variation, especially to those fabrics that are sensitive to oxidation, has been
observed due to the presence of residual peroxide after bleaching [10]. Extensive
washing generating the bulk volume of alkaline wastewater or producing high salts instream processes due to treatment with Na 2 S 2 O 4 or NaHSO 3 are commonly applied
through the classical method [17]. Catalases are well known alternate bio-catalyst
having ability to remove residual peroxides by converting it into gaseous oxygen
and H 2 O with minimum pollution load [40]. The flaws of catalase in commercial
applications like high cost, low ability to withstand with high temperatures, alkaline
medium or its reactive nature towards dyes could be overcome by immobilizing
catalases or microbial cells on solid supports [41]. In this way, it is suggested that
the immobilizing of alumina or clay will not only help to control its action with
increased recycling ability [42].
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in cotton textiles [34]. Japanese scientists submitted a patent on scoured yarns with
out-standing tensile strength retention after treating for 18 h at 40 °C cotton fibers
or their blends with proto-pectinases [2].
3.1.3 Bio-bleaching
The pure white appearance of the fabric is a fundamental requirement for the dyeing
process [35]. H 2 O 2 in alkaline pH and near to 100 °C is the most commonly applied
agent in industries for the bleaching process. The whole process of chemical bleaching demands careful control to protect any damage of fiber from radical reaction
[36]. Moreover, a huge amount of water is needed for the removal of excess peroxide for the smooth dyeing process [2]. Although, in biological processing, H 2 O 2 is
generated from C 6 H 12 O 6 in aqueous media by glucose oxidize or at controlled rates
by the combination of any detergent [37]. So this process is preferred because of its
feasibility to reuse de-sizing waste baths with minimum utilization of sources [38].
Although many processes of bleaching are based on the enzymatic generation of
H 2 O 2 is still in practice [39]. However, laccase enzymes are used as bio-bleaching
agents, attached to hydroxyl groups of phenolics to fade colored flavonoids [13].
To overcome the limitations of the bleaching process or its related concerns like
processing costs, bio-bleaching or integration of the enzymatic process is a lucrative
substitute [35]. However, more benefits like temperature reduction, duration shortening and lower doses of hydrogen peroxide can be achieved by the integration of
chemical and bio-bleaching [14].
3.1.4 Enzymatic Cleansing
Shade variation, especially to those fabrics that are sensitive to oxidation, has been
observed due to the presence of residual peroxide after bleaching [10]. Extensive
washing generating the bulk volume of alkaline wastewater or producing high salts instream processes due to treatment with Na 2 S 2 O 4 or NaHSO 3 are commonly applied
through the classical method [17]. Catalases are well known alternate bio-catalyst
having ability to remove residual peroxides by converting it into gaseous oxygen
and H 2 O with minimum pollution load [40]. The flaws of catalase in commercial
applications like high cost, low ability to withstand with high temperatures, alkaline
medium or its reactive nature towards dyes could be overcome by immobilizing
catalases or microbial cells on solid supports [41]. In this way, it is suggested that
the immobilizing of alumina or clay will not only help to control its action with
increased recycling ability [42].