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Thursday, April 4, 2019

The Use Of Enzymes In Textile Industry Biology Essay

The Use Of Enzymes In Textile pains Biology EssayEnzymes be bio-catalysts and are use of goods and servicesd in several industrial processes since nineteenth century. Its use in textile industry is an example of industrial or white revolution. Enzymes, due to their non-toxic and eco-friendly characteristics, have gained great industrys in textile industry. Not only they are highly specific, efficient and work low moderate conditions but also they help reduce process times, save energy and water, improve quality of crossing and reduce pollution. As a result they are rapidly gaining global recognition as key requirement for textile industry.Commercially enzymes can be obtained from three primary sources, animal tissues, plants and microbes. However, these naturally occurring enzymes are not produced in sufficient quantities to be readily use in industrial applications. Hence, microbial strains producing the coveted enzyme are cultured and optimised i.e. fermentation, to ob tain enzymes in sufficient quantities for their commercial use in textile industry. The enzymes used in the textile industry are amylases, cellulases, pectinases, lipases, catalases, proteases, xylanases and so on and are mainly used for processing of the textiles i.e. propaedeutic and finishing of the goods. Some of the applications include removing of stiffen, bleaching, degrading lignin, fading of jean and non-denim, removal of peroxidises, finishing of wool, decolouration of dyestuff, bio-scouring, bio-polishing, wool finishing, etc. (Shenai, 1990 Nalankilli, 1998 Barrett et al., 2003Cavaco and Gubitz, 2003 Chelikani et al., 2004).CLASSIFICATION AND PROPERTIES OF ENZYMES USED IN TEXTILE intentnessEnzymes are very specific toward catalysing the substrate. Hence these are classified on the basis of their catalytic functions in six broad categoriesEC1 Oxidoreductases catalyze oxidation and or reduction reactionsEC2 Transferases catalyze transfer of a functional groupEC3 Hydrol ases catalyze the hydrolysis of various bondsEC4 Lyases catalyse sectionalization of various bonds by means other than hydrolysis and oxidationEC5 isomerases catalyse isomerisation changes within a atomic number 53 moleculeEC6 Ligases joining of two molecules with formation of covalent bondsProperties of enzymes exploited for use in industrial applicationAcceleration of the reaction rates by lowering the activation energy of the reaction.Operating optimally infra milder conditions of temperature, pH and atmospheric pressure.Alternative for polluting, toxic and carcinogenic chemicalsHigh specificity towards substrate makes easy to control their legal actionBiodegradable and do not produce toxic wastes.Due to their high efficiency, specificity, property of working under milder conditions and biodegradability enzymes are well suited for various industrial applications.ROLE FO ENZYMES IN TEXTILE INDUSTRYUse of enzymes in various textile processing processes has greatly benefited te xtile industry with respect to twain environmental impact and quality of product. There are 7000 known enzymes, but only 75 are commercially used in textile industry (Quandt and Kuhl, 2001) and most of them belong to hydolases and oxidoreductases families. The hydrolases family includes amylases, cellulases, pectinases, proteases, catalases and lipases/estarases and oxidoreductase family include laccase, peroxidises.AMYLASESAmylases actson starch molecules and hydrolyses to snuff it dextrin and small polymers of glucose units (Windish and Mhatre, 1965). These are classified according to the sugars they produced i.e. -amylases and -amylases. -Amylases being produced from filamentous fungi and bacteria are broadly speaking used in industries (Pandey et al., 2000). This enzymes are stable over wide range of pH from 4-11 and optimal military action is re after-hoursd to the growth conditions of the source microorganisms (Vihinen and Mantsala, 1989). In general, -Amylases shows high specificity towards starch followed by amylase, amylopectine, cyclodextrin, glycogen and maltotriose (Vihinen and Mantsala, 1989).1.1 Textile Desizing size of it is an adhesive substance used to coat the wrapping threads used in weaving of the cloths do from cotton or blend. Starch and its derivatives are broadly used to size fabrics due to their easy availability, sexual intercourse low cost and excellent film forming capacity (Feitkenhauer et al., 2003). Amylases are used to remove this sizing square and prepare the fabric ready for dyeing and finishing (Cavaco-Paulo et al., 2008). Earlier to the discovery of amylases, desizing was done by chemical treatment of fabric with acid, alkali or oxidising agents at high temperature. But, this technique was inefficient in removing the starch which resulted in imperfections in dyeing and also degradation of cotton fibre. Amylases are commercially used for desizing fabric due to its efficiency and specificity and its effectiveness in co mpletely removing the size without affecting the fabric (Cegarra, 1996 Etters and Annis, 1998). Starch is outside during washing in the form of water soluble dextrin and thus reduces the discharge of chemical waste into the environment.2.0 CELLULASESCellulases are the hydrolytic enzymes that catalyses the breakdown of cellulose to smaller oligosaccharides and finally to glucose. These enzymes are commonly produced by soil-dwelling fungi and bacteria such as Penicillium, Trichoderma and Fusarium (Verma et al., 2007) and shows optimal activity in temperature range from 30C-60C. The applicationof cellulases in the textile industry begin in late nineteenth century with denim finishing. It alone accounts for 14% of the worlds industrial enzyme market (Nierstrasz and Warmoeskerken, 2003).2.1 DENIM FINISHING jean is high grade cotton and its washing is done in order to give a have on look e.g. stonewashing of denim jeans, in which the denim fabric id faded using sodium hypochlorite or o ne thousand permanganate are used as pumice stones (Pedersen and Schneider, 1998) it resulted in damage to the fabric and machine. Introduction of cellulases have change magnitude the productivity without affecting garment or the machine. Cellulases hydrolyses the exposed surface of dyed (indigo) fabric leaving the interiors intact, uncomplete hydrolyses of the surface results in removal of dye and leaves a light area. Most of the cellulases are produced from fungi, but cellulases from bacterial and actinomycetes origin are now studied with regard to its use in bio-stoning of denim. Cellulases used for washing of the denim can be further classified on the basis of optimal pH required for its maximal efficiency as neutral cellulases operating at pH 6-8 and acidic cellulases acting at pH 4.5-6.2.2 BIO-FINISHINGWashing of cotton and other natural and man-made cellulosic fabrics, besides denim, such as linen, hemp, rayon and viscose by enzymatic activity of cellulases to improve fin al appearance is done by bio-finishing or bio-polishing processes (Videbaek and Andersen, 1993). The process helps in preventing the formation of ball of fuzz called pill on the surface of the garment, this formation usually results in unattractive, winding fabric appearance. Cellulases, hydrolyses the microfibrils protruding from the surface of the fabric which tends to break off leaving a smoother surface.Bio-finishing whitethorn be an optional step for upgrading cotton fibrics, but is very important step in streak of pilling or fibrillation during finishing of lyocell fabrics (Cavaco-paulo et al., 2008). Similarly, Carrillo et al. (2003) stated that cellulases can be used for viscose type regenerated celloloses like viscose and modal. Yachmenev et al. (2002) showed the use of ultrasound as an efficient way to improve the enzymatic activity in bioprocessing of cotton.

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