INTRODUCTION:

Globalize or vanish is today's slogan. Globalization of market has brought a new set of challenges all over the globe in this fast moving millennium. Textile processing industry has to face the significant challenges to maintain the eco standards, to save the environment as well as to survive for the fittest. So the application of bio-tech and eco friendly chemicals and auxiliaries will be the proven solution for future. The meaning of eco friendly is to use such dyes and chemicals and processing ingredients which are biodegradable and having no content of harmful hazardous ingredients. Eco friendly textile is the order of the day. Eco friendly means not only environmental protection but also energy conservation.

In pure scientific terms biotechnology is defined as application of biological organisms, systems and processes to manufacturing and processing industries. This is reflected in extraordinary ability of enzymes to recognize other biological systems and to catalyse a vast range of specific chemical reactions under moderate and hence much more economic conditions.

The history of identifying enzymes is over 100 years old., while that of using purified enzymes commercially is 60 years old. Among 2000 enzymes reported so far around 150 are found to be of great importance for various industrial processes, which involve applied microbiology and biochemistry. Major sources of commercial enzymes are plants, animals and micro-organisms.

With advent of genetic engineering, technology has reached a stage where synthetic polymers i.e. polyester fibres can be etched with the help of enzymes. The term BIOTECHNOLOGY is used to refer to the textiles that are based on enzymes. The well established enzymatic process has many advantages but the major hindrance to its industrial application is the high cost of enzyme production. An efficient production method, employing a cheap and easily available substrate and a good cellulolytic organism, will reduce the cost of the enzyme preparation and improve the economy of the overall cellulose bioconversion. In this paper our attempt is to overview the application of biotechnology in different fields of textile.

APPLICATIONS OF BIOTECHNOLOGY IN VARIOUS TEXTILE FIELDS:

The progress now being made in biotechnology and the current level of investment by governments and individual companies has enormous commercial implications for many sectors of industry in the years ahead. Biotechnology has already developed new products, opened up new markets, speeded up production and helped to clean up the environment. The textile industry was identified as a key sector where opportunities available from adapting biotechnology are high but current awareness of biotechnology is low.

Enzymes operate at mild pH (3.5 9), relatively low temperatures (10 800C) and at normal atmospheric pressure. They can be produced at low costs in virtually unlimited quantities and hold out potential for reuse. So, enzyme users reap benefits of energy savings and reduced costs. Their adoption also makes savings possible in fixed capital costs as enzyme catalysed process operate under mild conditions of pH, temperature and pressure than their chemical counter parts. These enzymes usually operate under mild conditions of pH and temperature. Many enzymes exhibit great specificity and stereo selectivity.


About the author:

I am Shivendra Parmar completed my M.Tech in Textile Technology at Textile institute of technology and Science,Bhiwani CDLU University during 2002 .I did my B.E in Textile Technology at Shri Vaishnav Institute of Technology and Science, Indore and passed out in First Class during the year 2002.So far published 4 articles in National and International Journals and presented one paper in national conference. Currently working as lecturer & placement coordinator in the department of Textile Technology, Shri Vaishnav Institute of Technology and Science, Indore. Also contribute in TEXTILE ASSOCIATION OF INDIA,M.P UNIT as a Jt. Secertary. EMAIL: shivendra_parmar@rediffmail.com

I am Tanveer Malik completed my M.Tech in Textile Manufacturing at Veermata Jijabai Technological Institute (VJTI), Mumbai University during dec 2001 .I did my B.E in Textile Technology at Shri Vaishnav Institute of Technology and Science, Indore and passed out in First Class during the year 2000.So far published 3 articles in National and International Journals. Currently working as lecturer in the department of Textile Technology, Shri Vaishnav Institute of Technology and Science, Indore. Email: tmalik35@yahoo.com

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Research in biotechnology has already resulted in new analytical methods for the textile industry. Work on molecular biology at BTTG has led to the development of species-specific DNA probes for animal fibres. These probes can be used to detect adulteration of high value speciality fibres such as cashmere by much cheaper fibres (e.g. wool and yak hair). Rapid methods have been developed to assist in the early detection of biodeterioration of textile and other materials. Studies carried out at BTTG have shown that the presence of viable micro-organisms on textiles can be assessed using the enzyme luciferase isolated from the firefly (Photinus pyralis) which releases light (bioluminescence) in combination with adenosine triphosphate produced by the micro-organisms.

1.ADVANCING IN PLANT BIOTECHNOLOGY (COTTON)

Advancing in plant biotechnology have overcome several barriers resulting in crop improvement by making entire gene pool for utilization. A novel concept for including male sterility and fertility for hybrid seed production has been developed by plant genetic system (hybrid cotton). Development of Bt. Cotton through the introduction of gene from Bacilius thuringenesis would produce an insecticidal toxin thereby protecting against the attack of a variety of a lepidopteron caterpillars. Here by biotechnology the characteristics of cotton get improved, which results in better quality of yarn and fabric.

2. BIO-POLISHING

Bio-polish treatment is imparted to any fiber or fabric to improve its smoothness and shine on the fabrics surface by removing fiber-yarn ends projecting from it. This contributes to a pleasing feel, which increases appeal for fashion uses.

2.1. Bio-polising treatment for wool

The process involves two steps. First, an activated peroxide bleach is used to whiten the wool fibers and remove the protective lipid barrier that surrounds them. This step bleaches the wool at lower temperatures and in half the time as conventional techniques, which cuts processing costs, according to Cardamone. And because it removes the lipid layer, the peroxide treatment also makes the fibers more receptive to dye.

High-temperature dyeing is traditionally used with wool because of the lipid barrier to dye uptake, Cardamone says. Although wool has resilient properties, those high temperatures weaken the fiber. Our process lets wool be dyed at lower temperatures, preserving its strength.

The second step enzyme treatment is what makes machine-washable wool a reality. The surface of a woolen fiber is covered with microscopic scales, somewhat like scales on a fish or shingles on a roof. Wool shrinks during machine-washing because the heat and pressure lock the scales in place. The enzyme treatment digests the scales so they can't become locked. This controls shrinkage without loss of strength or elastic recovery. The same lipid layer that makes wool resistant to dye uptake would usually protect the scales against such an enzyme attack. But the bleaching step removes that protection. No damage is done to the underlying fiber structure, and the fabric's mechanical properties are not changed, because the enzyme activity is limited to the outside layer, or cuticle, Cardamone says. An additive is used in both the bleach pretreatment and the enzyme treatment to keep the enzymes out of the fiber's inner structure.

The process can be applied to everything from loose fibers to yarn, fabric, or completed garments.

2.2 Biopolishing of Lyocell

Lyocell has a unique property: it has a tendency to fibrillate. Fibrillation is the longitudinal splitting of a single wet fibre into microfibres, caused by mechanical stress. Hence, all processes that abrade the Lyocell fibre in wet conditions will generate some fibrillation. Wet processes such as desizing, dyeing and laundering will produce fibrillation. It is therefore necessary to clean the surface free of all fibrils (defibrillation). Initially, however, a process of pre-fibrillation is carried out, in which the surface is fibrillated to the maximum extent. This process can be carried out with desizing. After the primary fibrillation, the fabric or garment can be enzymatically defibrillated (Biopolished) using a cellulase. The cellulase acts by weakening the ends of fibres protruding from the fabric, while mechanical stress break off the weakened fibres.

The Biopolishing of Lyocell is influenced by a number of factors:

Machinery selection: the higher the level of mechanical action the shorter should be the incubation time with enzyme;

liquor ratio: at very high liquor to fabric ratio a dilution effect occurs - less enzyme activity;

pH: enzyme activity is influenced by pH. If the optimum pH is employed the optimum enzyme activity will be observed, so incubation time and enzyme and energy costs can be kept to a minimum;

Temperature: if the temperature falls outside the optimum range then adjustments to enzyme dosage or incubation times must be made.

3. APPLICATION OF BIO TECHNOLOGY FOR BAST FIBRE

3.1 Flaxzym and ultrazym retting of flax

Retting, which is the first step in the processing of bast fibre is generally a microbial process in which stem pectins are degraded there by freeing fibre bundles from the epidermis/cuticle barrier and from the woody shive. The practice of water retting which produces high quality fibre has been abandoned in western countries because of environmental pollution resulting from a fermentation products of anaerobic bacteria and high labour cost of drying.

Enzymatically retted flax

Commercial enzyme mixtures such as flaxzym and ultrazym are effective in separating fiber bundles from the epidermis/ cuticle layer and from the shive material and also in reducing the size of bundles. Inclusion of chelators such as ethylenediamine tetra acetic acid or oxalic acid with the enzymes, long with mechanical disruption of stems, improved the efficiency of enzyme retting.

3.2 Effect of enzymatic treatment on linen

Lenen fabric were treated with enzyme acting on hemicellulose, pectin and protein. The linen fabric was treated with purified enzymes acting on pectin,xylan and glucomannan. In order to enhance the hydrolysis efficincy EDTA was added to the polygalactureonase treatment. The accessibility of the hemicellulose carbohydrates was surprisingly low as less that 0.7percent of the fabric d.w. was solubilized in the treatment despite of high enzyme dosage used.

4. APPLICATION BIO TECHNOLOGY IN PROTEIN FIBERS

4.1 NOVEL FIBERS THROUGH CLONING (PROTEIN FIBERS)

Genetic engineering methods are being investigated with their potential to produce new kind of textile fibers. DNA cloning is defined as the multiplication of the particular sequence of DNA, through the multiplication of the carrier cell. The system falls in to two main groups. These are those systems that can produce monomeric protein molecules in solution from appropriately engineered genes include expression in bacteria  cell culture or in the milk of transgenic animals. The protein monomers are isolated and spun. Other approaches to modify keratin fibers by expressing other proteins in the internal components by transgenesis. Milk fibers and spider web fibers are some of the fibers produced genetically.

Some genes relevant to fiber strength and length have been sought and cleaned. Rabbit hair keratin genes has been sought and cleaned. Rabbit hair keratin genes has been cloned and transferred successfully in cotton plants.

4.2 Shrink Proofing Treatment For Wool:

The surface of wool and other animal fibers is covered with a scaly cuticle. This cuticle is responsible for shrinkage problems that occur when wool is laundered. Treatment to avoid felt shrinkage has involved treating wool with either chlorine-based chemical in order to remove the cuticle or synthetic resins to cover the surface of the fiber. In these methods, the wastewater from the processing can contain AOX (absorbable organic halogens), which are harmful to the environment. Furthermore, wool that has been treated with resins usually has a poor hand and reduced water absorption and desorption abilities. Due to these factors, the dyeing industry has been calling for the development of shrink-proofing technology free from chlorine-based chemicals.

Extraction of new keratin-degrading enzyme suitable for use in shrink-proofing treatment for wool was isolated from mold.

a)Mold capable of effectively degrading keratin extracted from soil samples taken from different locations.

b)Because this enzyme acts preferentially on the cuticle that is responsible for felt shrinkage, it gives woolen fabric an excellent resistance to shrinkage without weakening the fiber or damaging the hand.

c)Furthermore, use of this enzyme can lead to the elimination of environmental problems associated with chemicals used in other treatment methods.

4.3 Anti-Felting Finishing Of Wool

Chlorine resin technologies have been successfully and widely used in the anti-felting treatment of wool because of organic halogens, environmentally unfriendly compounds involved in the treatment, it might be replaced sooner or later. With a rapid development of bio techniques, enzymatic treatments of wool has been considered as one of the most possible alternatives to the chlorine treatment. Protease SZ has remarkable anti-felting effect on wool by perzym process.

4.4 Carbonisation of wool

An analogous procedure to the desizing of cotton goods is the carbonisation of wool, where contaminating vegetable matter is removed from the protein fibres before dyeing, since the dyeing characteristics of wool and cellulosic materials is very different. Carbonisation usually comprises a treatment with a strong acid. The wool fabric is incubated in sulphuric acid solution and heated. The vegetable matter is converted to carbon, which is removed by beating or in subsequent scouring steps. However, care has to be taken that the treatment does not damage the wool fibres.

Research has been carried out (Sedelnik, 1993) to replace the acid treatment by an incubation with a mixture of cellulases and pectinases to hydrolyse the cellulose and lignin of the vegetable contaminants to water-soluble substances, which would easily be removed from the wool fabric. This process would be harmless to the wool fibres and require lower operational costs.

4.5 Degumming of silk

The fibroin filaments of cocoon silk are naturally gummed together with the protein sericin. The latter comprises about 25% of the weight of the cocoon and is soluble in hot water. The removal of sericin from raw silk is known as degumming. The methods of degumming are classified according to the degumming agents employed (e.g. soap degumming, alkaline degumming).

Enzyme degumming involves proteolytic degradation of sericin using a specific protease, which does not attack fibroin. As a milder mechanical treatment may be used with enzymatic degumming, the finished silk is smoother than that degummed with soap. The silk affinity to reactive dyes is also significantly improved by the enzymatic treatment. Novo Nordisk market an enzyme preparation suitable for degumming silk (Alcalase 2.5 L).

A number enzymatic treatments have been developed (Novo Nordisk) to improve the comfort and appearance of wool. An enzyme preparation known as Novolan can be used to treat wool. Novolan imparts to wool a durable softness, a unique handle have produced and marketed and reduces the fuzziness usually associated with wool fabric.
Novolan is a protease with a pH optimum of 8.5 and an optimum temperature of 55C.

The activity of Novolan is enhanced by chlorination and weight loss of wool fabric can occur if too much chlorine remains from earlier bleaching processes. It is better to avoid too much mechanical agitation during the incubation with enzyme. The following three stages are recommended for dyed and chlorinated, knitted or woven worsted wool:

5. APPLICATION BIO TECHNOLOGY IN TEXTILE WET PROCESSING

5.1 Applications of Enzymes in Textile Industry

Enzymes are used in the textile industry, mainly in the finishing of fabrics and garments.

Major applications include:

1.Bio-Singeing
2.Bio-Desizing
3.Bio-Scouring
4.Bio- Carbonizing
5.Bio-Stoning

5.1.1 Bio-Singeing

This mode has been specifically developed to achieve a cleaner pile on terry towels. A treatment with Ultrazyme LF Conc � a powerful Cellulase composition gives a clear look to the pile, improved absorbency and softness.

Fabrics containing cellulosic fibers often show fuzzy surface due to chafing during wet processing. A smooth and clear finish can be achieved by bio-singeing.

5.1.2 Biodesizing

Complete removal of starch-containing size without fiber damage is best obtained by using enzymatic desizing agents. Formerly amylase derived from mold, pancreas or malt where used in desizing. Today liquid bacterial amylase preparations dominate.

The enzymatic desizing process can be divided into three stages.
Impregnation
Incubation
After wash

Impregnation: Enzyme solution is absorbed by the fabric. This stage involves thorough wetting of fabric with enzyme solution at a temperature of 70C or higher with a liquid pick up of 1 liter per kg fabric. Under these conditions there is sufficient enzyme stability (temperature, pH, calcium ion level govern the stability). During this stage gelatinization of the size (starch) is to the highest possible extent.

Incubation: The enzyme breaks down the size. Long incubation time allows a low enzyme concentration.

After-wash: The breakdown products from the size are removed from the fabric. The desizing process is not finished until the size breakdown products have been removed from the fabric. This is best obtained by a subsequent detergent wash (with NaOH) at the highest possible temperature.

Desizing could be done in:

Jigger or winch
Pad-roll
J box
Pad  stream

5.1.3 Bio-Scouring:
Enzymes are structurally composed of polypeptides with molecular weights ranging from approximately 103to 106. In a heterogeneous reaction like cotton scouring, the kinetics of enzymatic reaction is influenced by rate of diffusion of bulky reactants into cotton fiber. In cotton the major portion of impurities is located in its primary wall and cuticle of the fiber. This is favorable for the action of macro molecules used in bio-scouring enzymes.

Factors influencing scouring are the nature of the substrate, the kind of enzyme used, the enzyme activity, the use of surfactants and mechanical impact. It was observed that, during pectinase scouring, much less wax was removed compared with the alkaline scouring. If the treatment was combined with surfactant treatment, results equivalent to alkaline scouring could be achieved. A water treatment at 100C is reported to increase the effectiveness of the subsequent scouring of cotton fabric with a combination of pectinase, protease and lipase, results equivalent to alkaline scouring could be achieved.

Whereas the use of these enzymes alone shows a very little effect. A new pectinase (BioPrep, NOVO Nordisk A/S) was screened that is stable under alkaline condition, i.e. the optimum conditions for removal of cotton adhering substances. Pectinase action does not create full removal of cotton adhering substance. Pectinase action does not create full wetability alone. Surfactants, Ca-binding salts, emulsifiers and high treatment temperatures complete the removal of the Ca-pectate/wax complex. The relative colour depths of caustic soda-scoured and environmentally friendly bioprepared fabrics do not show significant differences one important step is scouring is the complete or partial removal of the non-cellulosic components found in native cotton as well as impurities such as machinery and size lubricants. Traditionally this is achieved through a series of chemical treatments and subsequent rinsing in water. This treatment generates large amounts of salts, acids and alkali and requires huge amounts of water.

Bio-scouring systems:

The bio-scouring process is built on

▪ Protease,
▪ Pectinase &
▪ Lipase enzymes that act on proteins, pectins & Natural waxes to effect scouring of cotton.

Advantages of bio-scouring:

Milder conditions of processing, low consumption of utilities, yet excellent absorbency in goods.

No oxy-cellulose formation and less strength loss because of absence of heavy alkali in bath

Uniform removal of waxes results in better levelness in dyeing

Highly suitable for scouring of blends containing fibers like silk, wool, viscose, modal, lyocell, lycra etc.

Low TDS in discharge

Fabric is softer and fluffier than conventional scouring, ideal for terry towel/knitted goods

5.1.4 Bio-carbonizing

In the industry sulphuric acid is used for carbonizing. But it make problem for the effluent treatment process.
In bio-carbonizing process the good are treated with a cellulose enzyme based formulation Chemizyme UZ to achieve dissolution of cellulose component. The process offers an eco friendly option of the obnoxious use of strong acids.

5.1.4.1 Carbonizing of polyester:

Dyed or printed polyester-cellulosic blends are often treated with a strong solution of sulphuric acid to dissolve the cellulosic component. The treated goods have a soft and

fluffy feel. The process is risky due to use of highly corrosive acids that is also difficult to treat in effluent treatment plant.

In the bio-carbonising process the goods are treated with a cellulose enzyme based formulation chemizyme UZ to achieve dissolution of cellulosic component. The goods are padded in a warm solution of this product and batched on a roll under normal conditions and are washed off after 12-16 hours. This process offers an eco friendly option to the obnoxious use of strong acids.

5.1.4.2 Carbonizing of wool:

The use of sulphuric acid to remove vegetable matter from wool (carbonisation) has a number of drawbacks. A combined cellulase, pectinase and xylanase treatment degraded up to 7% of the vegetable matter but there was no improvement on this after combing. Protease treatments had also been assessed. A more even dyeing (based on examination of wool fibre cross-sections) was achieved in semi-industrial trials following the enzyme treatment.

5.1.5 Bio stoning

The stone-washed jeans-look is obtained by washing the indigo-dyed jeans with abrasive pumice (volcanic) stones. However, these stones wear out the fabric, damage the washing machines and break apart. Several rinsing processes are needed to get rid of the stones afterwards.

Biotechnology, a new biological method has emerged. A type of enzyme called a cellulase has been developed to replace the pumice stones. Jeans are made from cotton, a cellulosic material. The cellulase enzymes are capable of breaking down the surface cellulose fibres of the jeans in a controlled manner without seriously damaging the fabric.The same worn look is achieved, while considerable savings are made in terms of time, volume, waste, water and wear on machines. Enzymes developed for the textile industry can improve production methods and fabric finishing. For example, cotton fibre cleaning with enzymes also increases the efficiency when indigo-dyeing.

6. APPLICATION OF BIO TECHNOLOGY IN GARMENT PROCESSING

6.1 Bio polishing of cotton fabrics

Biopolishing may be carried out at any time during wet-processing, but is most conveniently performed after bleaching. The advantage of carrying out Bio polishing at

this stage is that the fabric is clean, hydrophilic and more accessible to the cellulases. Higher concentrations of enzyme would be required for grey fabric. If Bio polishing is done after dyeing there is a risk of color shade change. Also the dyestuff may reduce the performance of the enzyme, so that a higher concentration of enzyme would be required. Direct and reactive dyes are known to have an inhibition effect on cellulases.

The Biopolishing process requires:

Equipment such as a jet-dyer and winch

Enzyme dosage 1-2 % owf (on weight of fabric)

PH 4.5-5.5

Temperature between 40-55 C

30-60 min.

6.2 Stonewashing of Denim

Stonewashing without stones: Stonewashing jeans no longer require stone. A new biotech process using enzymes create the same look while doing less damage to jeans, washing machines and the environment.

Stonewashing of denim with enzymes instead of pumice stones is an example of environmental bnefits. Enzymes are expected to have an even greater impact on effluent quality as more fibre preparation, pre-treatment and value-added finishing processes convert to biotreatment. Biotreatment may also be effective in eliminating biological oxygen demand (BOD) and removing and/or decolourising dyes in textile waste streams. Since enzymes are very effective catalysts even under mild conditions, they do not require the high energy input often associated with chemical processes. Therefore, in terms of the environment, biotechnology offers the opportunity to develop cleaner and more energy-efficient processes, produce higher quality products, and clean up effluents.


7. BIO-TECHNOLOGY IN WASTE WATER TREATMENT

Biotechnology can be used in new production processes that are themselves less polluting than the traditional processes and microbes or their enzymes are already being used to degrade toxic wastes. Waste treatment is probably the biggest industrial application of biotechnology. Specific problems pertaining to the textile industry include colour removal from dyehouse effluent, toxic heavy metal compounds and pentachlorophenol used overseas as a rot-proofing treatment of cotton fabrics but washed out during subsequent processing in the UK. Currently much research is being carried out to resolve these problems and biotechnology would appear to offer the most effective solutions. Reduction in BOD and COD is also facilitated due to biotechnology.

CONCLUSION:

Since the textile industries is the one of major water consumers, the problem faced by the textile industries is of effluent and waste disposal. Also red listed chemicals and banned dyes are carcinogenic and highly toxic. It is the quantity of contaminants present in the final product cause harmful effect on human body. On the other hand with increasing awareness for quality of environment, the environmental related regulations are becoming stricter day by day world over. A number of processes by means of which one can make eco-friendly by substituting conventional chemicals by eco friendly chemicals, recycling of textile wastes etc. eco friendly chemical processing is the order of the day so

it has become requirement to adopt positive approach to eco friendly processing so that final product may be considered clean.

ACKNOWLEDGEMENT:

First of all we would like to express profound gratitude to the management of the institute, Principal Dr.Ing.V.P.Singh,and Advisor Prof. Dr.H.V.S.Murthy and Head of the department Prof.Dr. Prabhakar Bhat for giving encouragement and guidance to work on Application of Bio-Technology In Textiles

REFERENCES:

1.Churi R.Y., Khadilkar S.M. and Sule S.S., 'Enzyme Systems for processing cellulosic textiles': COLOURAGE - APRIL 2004

2.Application of Genetic Engineering and Enzymes in Textiles IE (I) Journal-TX Vol 84, February 2004

3.Effect of various scouring system on the accessibility of dyes into cotton Coloration Technology vol. 120 no. 6, 2004

4.The Council for Biotechnology Information. http://www.whybiotech.com

5.Bringing the benefits of biotechnology to textiles and clothing Symposium on Biotechnology in the Textile Industry Portugal, 3-7 May 2000

6.Enzymatic hydrolysis of cotton fibers: modeling using an empirical equation, Journal of Cotton science vol. 8 issue 4,2004

7.royalb@eng.auburn.edu