Cotton enzymatic treatments

Yachmenev, V. G., Blanchard, E. I, and Lambert, A. H. 1999. Study of the influence of ultrasound on enzymatic treatment of cotton fabric. Textile Chemist Colorist American Dystuff Reporter, 1 (1), 47-51. 

The effects of cellulase enzymes on cotton substrates that were dyed with various classes of dyes have been reported. It was found that vat dyes do not inhibit cellulase activity on cotton, and hydrolysis of the substrate with subsequent color removal transpires. In contrast, cellulase activity on cotton was inhibited by the presence of some direct and reactive dyes. There is the probability that a dye-enzyme complex is formed with less activity than that of the free enzyme. The increased weight loss from enzymatic treatment on untreated cellulose is associated with a slight reduction in dye sorption, and this may be because of a reduction of amorphous regions in cellulose where dye molecules are usually sorbed. Cellulase activity is more prominent on mercerized cotton than on unmercerized cotton. This is because mercerization is associated with a decrease in the crystallinity of the cellulosic structure [540]. One major negative aspect of cellulase treatment of cotton fabric is the strength loss associated with the approximately 3-5% weight reduction under normal treating conditions. Of course, this is to be expected after cellulose is hydrolyzed. Future research efforts may lead to processes in which enzymes... 

Enzymatic treatment of unscoured cotton fabric can be done with pectinase. 

Enzymatic methods Many research organizations and scientists are working to improve the environment-friendly processing of cotton fabrics with enzymes. The many enzymes are today available for the removal of Impurities in the cotton fibers. For example, alpha amylase is enzyme used for cotton desizing process, pectlnase for pectin removal in cotton fiber and lipase, and protease for fatty substance removal in the cotton fiber treatments. Typical textile wet processing of cotton materials is shown in Fig. 4.6. 

Csiszar, E., Szakacs., G., and Rusznak, I. (1998). Combining traditional cotton scouring with cellulase enzymatic treatment, 68(3),... 

Scouring and bleaching of cotton fabrics are also attractive targets for enzyme-based processes, due to the severe environmental impact of these processes. These processes are also very energy demanding. Raw cotton contains about 10% of impurities. Pectins, waxes and coloured components can all be partially removed from raw cotton by enzymatic treatments but the residual seed coating remains a problem. 

Cotton processing provides several possibilities for enzyme applications. The removal of cotton impurities is essential for fabric manufacture and is generally carried out by scouring with alkali. However, environmentally harsh scouring can be replaced with an enzymatic treatment, in which cotton impurities, such as protein, wax, pectin and ash, can be efficiently removed... 

Figure 2. Effect of various treatments on the susceptibility of cotton cellulose to enzymatic hydrolysis (16)...

Spicka, N., Forte-TavJer, P, 2013b. Complete enzymatic pre-treatment of cotton fabric with incorporated bleach activator. Text. Res. J. 83 (6), 566-573. 

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