Role of Enzymes in Textile Wet Processing: An Insight

Mr. Rohit Srinivasan, Director of Technology, Quantumzyme

Introduction
The use of enzymes within the textile industry is one of the most rapidly growing fields within the domain of industrial enzymology. The enzymes used in textiles are catalase, amylases and laccase used in removing starch, degrading excess hydrogen peroxide, bleaching textiles and degrading lignin. The use of enzymes in textile chemical processing is rapidly gaining global recognition due to their eco-friendly and non-toxic characteristics.

Use Of Enzymes In Textile Processing
The most recent commercial advances include the application of cellulases for denim finishing and lactases for decolourisation of textile effluents and bleaching. What makes enzyme technology attractive is its highly specific and efficient characteristics and the ability to work under mild conditions. Further, enzymes reduce the process time, energy and also saves water. It also ensures improved product quality and potential process integration. The goal is to provide a textile technologist with an understanding of enzymes and their use in textile materials.

This is how enzymes helps in the process of textile wet processing:
▪ First, the enzyme helps in accelerating the reaction by lowering activation energy and acts as a catalyst by remaining intact till the reaction ends.
▪ Second aspect is that enzymes operate under a milder condition. Use of enzymes are common in catalytic concentrations at low temperatures and at pH values near to neutral.
▪ Thirdly, enzymes are the best alternative to hazardous, toxic, and polluting chemicals.
▪ Next, enzymes act only on specific substrates; for example, enzymes that are used in desizing do not affect cellulose thus retaining the strength of cotton.
▪ Fifthly, enzymes are easy to control because their activities depend upon optimum condition.
▪ Finally, all enzymes are biodegradable.
At the end of the reaction in which enzymes are used, the remaining solution can be simply drained because of the biodegradable nature of enzymes and they do not produce toxic waste and hence there is no pollution.

Application of Enzyme In Textile Wet Processing
Some of the major applications of enzymes in the textile wet processing include the following:

▪ Enzymatic Desizing
In enzymatic desizing, amylases are used to remove starch-based size for uniform wet processing. The best part is that an amylase enzyme can be used for desizing processes at a comparatively low temperature. The biggest benefit of these enzymes is that they remove starch without damaging the fabric.

▪ Enzymatic Scouring
Scouring refers to the removal of non-cellulosic material that are present on cotton’s surface. Generally, pectinase and cellulase are pooled together and used in bioscouring. In the process, pectinase destroys the structure of the cotton cuticle by digesting the pectin thereby removing the connection between the cuticle and cotton fibre’s body. On the other hand, the cellulase can help in destroying the cuticle structure by digesting the primary wall cellulose.

▪ Enzymatic Bleaching
Cotton bleaching is carried out to decolorize natural pigments and to give a pure white appearance to the fibres. The chemical flavonoid is responsible for the colour of cotton and hydrogen peroxide happens to be the most common industrial bleaching agent. Traditional preparation of cotton requires high amount of alkaline chemicals with huge quantities of water being generated.

However, radical reactions of bleaching agents along with fibre can reduce the degree of polymerization. Therefore, replacement of hydrogen peroxide by an enzymatic bleaching system would lead to substantial savings on washing water required for the removal of hydrogen peroxide. The process has an alternative which happens to be a combination of suitable enzyme system.

▪ Biopolishing
Biopolishing is carried out as a finishing process that improves the quality of fabric by reducing the fuzziness and piling property of cellulosic fibre. The process is carried out to eliminate micro fibrils of cotton through the action of cellulose enzyme. Biopolishing ensures the fabric has a cleaner surface, better lusture, a cooler and a softer feel.

The Last Words
The above-mentioned processes are just a few applications of biotechnology within the textile industry. However, many such potentials still remain to be explored. It goes without saying that biotechnology is widely applicable in the textile industry and it is sure to turn out to be a boon in the ever-changing ecological conditions as well as the economy.