Enzymes And The Textile Industry
Enzymes have found wide application in the textile industry replacing harsh and hazardous chemicals in various processes. They go a long way in improving production methods and fabric finishing by reducing effluent processing cost.
One of the oldest applications in this industry is the use of Amylases to remove starch size. The warp (longitudinal) threads of fabric are often coated in starch in order to prevent them breaking during weaving. Scouring is the process of purifying fabric of the native cellulosic fibres from impurities such as waxes, pectins, hemicelluloses and mineral salts. Research has shown that pectin acts like glue between the fibre core and the waxes, but can be destroyed by an Alkaline Pectinase. An increase in 'wettability' can thus be obtained.
Cellulases have become the tool for fabric finishing. Their success started in denim finishing when it was discovered that cellulases could provide the fashionable stonewashed look, traditionally achieved through the abrasive action of pumice stones. Cellulases are also used to prevent pilling and improve the smoothness and colour brightness of cotton fabric in a process that is called Biopolishing. In addition, a softer handle is obtained.
Creating an aged look on denim was the fashion of the time, while there was an increased emphasis on moving to environment friendly processes. Laccase and different types of peroxidase helped meet this need, being very effective for giving a novel finish to denim while replacing bleaching chemicals. Catalases are used for degrading residual hydrogen peroxide after the bleaching of cotton. Hydrogen peroxide has to be removed before dyeing. Proteases are used for wool treatment and the degumming of raw silk.
Furthermore, Advanced Enzymes is developing various enzymes and enzyme based solutions, replacing conventional age-old enzymes and hazardous chemicals. Thus, reducing processing time, minimising processing cost and the use of water. Enzymes for applications like wetting, dye wash off, bleaching any sort of dye etc., are in the advanced stage of development. If enzymes can do such wonders, let us first understand WHAT ARE ENZYMES? AND WHY WE NEED THEM?
WHAT ARE ENZYMES?
Enzymes are proteins. Like other proteins, enzymes consist of long chains of amino acids held together by peptide bonds. They are present in all living cells, where they perform a vital function by controlling the metabolic processes whereby nutrients are converted into energy and fresh cell material.
Furthermore, enzymes take part in the breakdown of food material into simpler compounds. Some of the best known enzymes are those found in the digestive tract where pepsin, trypsin and peptidases breakdown proteins into amino acids, lipases split fats into glycerol and fatty acids, and amylases breakdown starch into simple sugars.
Enzymes are basically biocatalysts. Enzymes are capable of performing these tasks because, unlike food proteins such as egg albumin, gelatine or soya protein, they help to catalyze reactions. This means that by their mere presence, and without being consumed in the process, enzymes can speed up chemical processes that would otherwise run very slowly, if at all.
ENZYME PROPERTIES
- Enzymes are specific
Contrary to inorganic catalysts such as acids, bases, metals and metal oxides, enzymes are very specific. In other words, each enzyme can breakdown or synthesize one particular compound. In some cases, they limit their action to specific bonds in the compound with which they react. Most proteases, for instance, can breakdown several types of protein, but in each protein molecule only certain bonds will be cleaved depending on which enzyme is used.
2. Enzymes are very efficient catalysts
For example, the enzyme catalase, which is found abundantly in the liver and in the red blood cells, is so efficient that in one minute one enzyme molecule can catalyze the breakdown of five million molecules of hydrogen peroxide to water and oxygen.
3. Origin - natural source
Enzymes are present in all biological systems. They come from natural systems and when they are degraded, the amino acids of which they are made of can be readily absorbed back into nature.
4. Enzymes work only on renewable
raw material Fruits, cereals, milk, fats, meat, cotton, leather and wood are some typical candidates for enzymatic conversion in industry. Both the usable products and the waste of most enzymatic reactions are non-toxic and readily broken down.