**6.1 Denim wash using neutral cellulase**

Cellulase enzyme application on denim finishing has started in the late 1980s. Cellulase enzyme can remove trapped indigo dye from the denim fabric, which causes non uniform shade fading & worn looking. Bio washing with cellulase enzyme is an ecofriendly and superior quality for denim fabric. Application of neutral cellulases enzyme is active in a wide temperature range from 30<sup>o</sup> to 60o C and based upon their application pH 6.6–7 cellulase [128, 129].

#### **6.2 Denim bleaching using laccase/mediator**

Eco friendly denim bleaching has been originated in the late 1980s due to adverse effect of the conventional chemical bleaching process. By oxidizing the flavonoids of denim fabric, laccase enzyme can enhance the whiteness of the fabric. Enzymatic bleaching system leads not only damage of the denim fabric but also save water consumption. There are some successful industrial laccase enzymes for denim bleaching are used as DenLite®from Novozyme (Novo Nordisk, Denmark) and Zylite from the company Zytex (Zytex Pvt. Ltd., Mumbai, India) [130].

## **7. Modification of synthetic fiber by enzyme**

Even though synthetic fibers are mostly hydrophobic, however improving the hydrophilicity along with some properties such as weaving comfort, anti- pilling, dyeability, antistatic charge generation by Enzymes are used. Different classes of enzymes such as cutinases, lipases and esterases are suitable for polyester modification. Less potential for surface hydrolysis of polyester modification were esterases. Esterases from *Thermobifida halotolearans* have performed for both PET and PLA surface hydrolysis [131]. Hydrolyzing the polyester has been carried out by cutinases obtained from *Aspergillus oryzae*, *Penicillium citrinum, Fusarium solani, Thermobifida fusca. Thermobifida fusca,Thermobifida celluloysitica* [132, 133]. Lipases obtained from *Humicola sp., Candida Antarctica,Thermomyces lanuginosus,Triticum aestivum. And Rhizopus delemar* considered as a suitable for polyester hydrolysis [132]. Digital printed polyester fabric was treated by lipases for improving the color fastness [133].

Laccases with a mediator have been performed to increase the hydrophilicity of nylon 66 fabrics [134]. For improving dye bath exhaustion with reactive and acid dyes on Nylon 66 fabrics were treated by proteases from *Beauveria sp.,* an amidase from *Nocardia sp.* and a cutinase from *F. solani pisi* [135]. It was confirmed that acid and disperse dyes showed higher exhaustion on the protease & lipase treated Nylon 6 [136]. Proteases from a novel *Bacillus* isolate improve hydrophilicity and cationic dye affinity of nylon fabric without affecting the mechanical properties [137]. The vinyl acetate moieties in PAN can be hydrolyzed by cutinases and lipases [138].

#### **8. Enzymatic treatments of ETP in textile industry**

Textile effluents are usually highly colored, presenting different chemical substances when discharged into waters after finishing processes. Textile effluents can be discolored through physical, chemical and biological technologies. Several researches have been carried out for the removal of dyes from industrial effluents by chemical, physical and biological techniques. The decoloration dyestuffs and recalcitrant compounds using some biological techniques such as anaerobic, aerobic and combined process [139]. WRF are the principal organisms which have been investigated for dye degradation and decolorization purposes. The major lignin mineralizing enzymes of WRF are LiP, MnP and laccase that are involved in dye degradation [140]. Other than these enzymes many oxidase including versatile peroxidase, glyoxal oxidase, aryl alcohol oxidase and oxalate decarboxylase can perform dye degradation [141]. Toxic organic compounds can be detoxified through oxidative coupling is mediated with oxidoreductases. The detoxification of toxic organic compounds through oxidative coupling is mediated with oxidoreductases [142]. Enzymes like laccase, manganese peroxidase and lignin peroxidase

catalyze the removal of chlorinated phenolic compounds [143]. Microbial oxygenases, such as monooxygenases and dioxygenases are active against a wide range of compounds [144].
