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research paper代写 生物论文代写 The Use Of Enzymes In Textile Industry

 酶是生物催化剂,自第十九世纪以来在几个工业生产过程中使用的。它在纺织工业中的应用是工业或白色革命的一个例子。酶由于具有无毒、环保的特点,在纺织工业中得到了广泛的应用。不仅他们是非常具体的,高效的,在温和的条件下工作,但他们也有助于减少处理时间,节约能源和水,提高产品质量,减少污染。因此,他们正在迅速获得全球认可,是纺织工业的重要要求。

商业上的酶可以从三个主要来源,动物组织,植物和微生物。然而,这些自然发生的酶没有产生足够数量的工业应用中很容易使用。因此,产生所需的酶的微生物菌株进行培养和优化,即发酵,获得足够数量的酶在纺织工业中的商业用途。在纺织工业中使用的酶是淀粉酶、纤维素酶、果胶酶、脂肪酶、过氧化氢酶、蛋白酶、木聚糖酶等,主要用于纺织品即准备和完成货物的处理。一些应用程序,包括去除淀粉、脱色、降解木质素,牛仔和非牛仔褪色,去除peroxidises,整理羊毛,脱色染料、生物洗涤、生物抛光整理,羊 毛,等(申爱,1990;nalankilli,1998;巴雷特等,2003;Cavaco和gubitz,2003;chelikani et al.,2004)。

Enzymes are bio-catalysts and are used 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 wide applications in textile industry. Not only they are highly specific, efficient and work under mild conditions but also they help reduce process times, save energy and water, improve quality of product and reduce pollution. As a result they are rapidly gaining global recognition as important 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 used in industrial applications. Hence, microbial strains producing the desired enzyme are cultured and optimised i.e. fermentation, to obtain 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 etc. and are mainly used for processing of the textiles i.e. preparatory and finishing of the goods. Some of the applications include removing of starch, bleaching, degrading lignin, fading of denim 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., 2003;Cavaco and Gubitz, 2003; Chelikani et al., 2004).

CLASSIFICATION AND PROPERTIES OF ENZYMES USED IN TEXTILE INDUSTRY

Enzymes are very specific toward catalysing the substrate. Hence these are classified on the basis of their catalytic functions in six broad categories:

EC1 Oxidoreductases: catalyze oxidation and or reduction reactions

EC2 Transferases: catalyze transfer of a functional group

EC3 Hydrolases: catalyze the hydrolysis of various bonds

EC4 Lyases: catalyse cleavage of various bonds by means other than hydrolysis and oxidation

EC5 isomerases: catalyse isomerisation changes within a single molecule

EC6 Ligases: joining of two molecules with formation of covalent bonds

Properties of enzymes exploited for use in industrial application:

Acceleration of the reaction rates by lowering the activation energy of the reaction.

Operating optimally under milder conditions of temperature, pH and atmospheric pressure.

Alternative for polluting, toxic and carcinogenic chemicals

High specificity towards substrate makes easy to control their activity

Biodegradable 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 INDUSTRY

Use of enzymes in various textile processing processes has greatly benefited textile industry with respect to both 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.