Modern Biotechnological Pretreatment Techniques

Dyeing of textiles and textile materials has been going parallel to the human life since time immemorial. Natural protein fibers especially wool, silk, and cotton are widely used for dyeing purposes in the modern textile industrial sectors due to their comfort when wearing. In this chapter, fiber protein structure-function relationships are briefly discussed with enzymatic processing routes of textile materials with respect to the increasing dyeing efficiency and other novel functional applications. Fiber/fabric (wool, silk, cotton) biomodifications are described in detail with respect to various classes of enzymes such as cellulases, lipases, xylanases, oxygenases, proteases, transglutaminase, tyrosinase, and laccase. With the processing and development of new dyeing and finishing strategies, enzymatic treatments have become important environmental friendly technologies which not only fulfill the demand of the traditional textile industry but also improve quality of our life, meet the requirement of textile industrial sectors in terms of minimizing pollution levels, environmental protection levels, comfort, and health.

Textile wet processing is one of the most polluting industrial processes. It is a complex process, and its complexity depends on the composition of textile material. From this point of view, new efficient strategies for cotton wet processing are needed, which are cost-effective and reduce the impact on the environment. The goal of this work is to accomplish most aspects of preparatory finishing (desizing, scouring) by means of “green chemistry,” or, in other words, nontoxic enzymatic treatments. To achieve this goal, a mixture of a-amylase (Am) and polygalacturonase (PG) enzymes from Trichoderma harzianum induced with orange peel was successfully produced. Partial purification of these enzymes using dialysis and chromatographic techniques was carried out, and the purified enzymes were characterized. Different effects on the enzyme activity, including temperature, pH, and surfactant, were studied. The treatment of cotton fabric in a single bath for desizing with Am or a single bath for scouring with PG was accomplished. The treatment conditions were optimized by varying the enzyme concentration, pH value, treatment temperature, and duration. Treatment effectiveness on fabric properties was evaluated via weight loss (%), violet scale shades, residual starch in fabric (%), copper number, tensile strength, and water absorbency (wettability). A combined process for desizing and scouring was applied to the raw cotton fabric using a mixture of Am and PG enzymes. The effect of the two enzyme concentrations at different incubation times on the desizing and bioscouring efficiencies was further studied.

Despite of the amazingly grown interest in cellulases due to their importance for biomass hydrolysis, their main industrial use is still related to textiles. The main application of cellulases are the removal of surface fibre fibrils from cellulosic fabrics to avoid pilling and improve fabric appearance and the ageing of indigo-dyed denim garments. Cellulolytic enzymes are also used in detergents to aid in the removal of fibre encrusted dirt and soil and to increase colour brightness of the washed garments and may be used for the treatment or recovery of cellulosic textile waste. The following chapter gives a short overview about cellulosic textile substrates and cellulose deconstructing enzymes and a detailed insight in the mechanism and the application of cellulases in textile processes.

res publication, 2013

Textile processing is a growing industry that traditionally has used a lot of water, energy and harsh chemicals. They are also not easily biodegradable. Biotechnology in textiles is one of the revolutionary ways to advance the textile field. Biotechnology offers the potential for new industrial processes that require less energy and are based on renewable raw materials, as well as the application of green technologies with low energy consumption and environmentally healthy practices. Due to the ever-growing costs for water and energy worldwide investigations are carried out to substitute conventional chemical textile processes by environment-friendly and economically attractive bioprocessesusing enzymes.This work represents a reviewofrole of biotechnology in textile processing. The aim is to provide the textile technologist with an understanding of enzymes and their use with textile materials.

2021

Biotechnology is an ecological advantageous and moreover economically benefi cial technology. The most established application of biotechnology in textiles has been in the fi eld of enzymatic pretreatment. Glucose oxidase (GOD) catalyse the oxidation of β-D-glucose into gluconic acid by utilizing molecular oxygen as an electron acceptor with a simultaneous production of hydrogen peroxide (HP). Glucose oxidases are commercially gaining a lot of attention in textile technology. In an enzymatic pretreatment, the textile substrate is less damaged when compared to a classical pretreatment. Enzymatic pre-treatments of cellulose fabrics often save large amounts of raw materials, chemicals, energy and water. Bleaching with glucose oxidase thus represents an economic and ecological potential when compared to the classical process with added hydrogen peroxide. This review represents the basic properties and production of glucose oxidases and their applications in textile technology.