Softening+and+fading+of+denim-+The+Work+of+Enzymes

**The Work of Industrial Enzymes: Softening and Fading of Denim**
(Page By Michael Chen, IB SL Biology Block E)

Have you ever wondered how today’s modern jeans get that faded and worn look? If I was answering this question twenty years ago, I would have said that you could rub the jeans with pumice stones. However today, as a result of advancing bio-technology, industries no longer need to "fade" jeans through stones, a process which can be damaging to jean material. "Stone washing" techniques have been replaced by the process of “biostoning.” Biostoning produces the similar desired affects which stones have on jeans, but yet instead with the help of enzymes. Notably, the industrial enzyme called **__cellulase__** can give jeans a faded look and a softer and smoother feel.

**What is Cellulase? (Brief overview)**
Cellulase is an enzyme (the “-ase” is a good reminder that it is an enzyme) which catalyzes the hydrolysis (breaking down) of cellulose. It was first produced from the fungus //Trichoderma reesei// but is mainly produced by symbiotic bacteria. The cellulose, which the cellulase breaks down, is decomposed into small fragments, especially glucose.

**How does Cellulase interact specifically with jeans?**
Most jeans today are at least partly made out of cotton. Cellulose is a main component of cotton and other natural plant fibers. Because the enzyme cellulase breaks down cellulose, consequently the cotton in jeans is affected when exposed to cellulase. The cellulase enzymes have the ability to break down the surface cellulose fibers of jeans. This process occurs when the cellulase binds to the cellulose on the cotton fibers and break the molecular bonds between them. Thus the dye particles are released from the surface of the jeans, producing this “faded” affect. Also interestingly, by manipulating the temperature and pH levels, different effects can be produced on the jeans. As we know, temperature and pH levels are both factors which affect enzymes at work.

**Other Applications of Cellulase**
Cellulase is an important enzyme not only in the textile industry. It can applied and used for many other different things. Firstly, cellulase helps in the processing of coffee because it can perform the hydrolysis of cellulose when drying beans. Furthermore, because cellulase has the ability to break down plant fibers, it plays an integral role in waste processing. Since alcohol is a main product, cellulase can be of use in the "biofuels" industry. Therefore, cellulase can help the fermentation of biomass into biofuels. Lastly cellulase enzyme can act as a treatment. If one has cellulose bezoarw within their stomach, a hard and indigestible mass of material, cellulase can help break the material down.

**My Works Cited:**
http://www.brookscole.com/biology_d/templates/student_resources/0030270448_tobin/webbit/ch05-01.html http://www.europabio.org/documents/JEANS.pdf http://134.68.135.1/jitt/sampler/biology/bio_archive/goodfor15.html http://www.answers.com/topic/cellulase