Eco‐friendly approach on wool pretreatment and effect on the wool structure and dyeability

Abstract

This research investigated the effect of various proteolytic enzymatic pretreatment on morphological and chemical features and the dyeability properties of wool fibres. Scoured merino wool fibres are treated with protease, papain, trypsin, and pepsin in specified conditions. Each enzyme activity measurement was provided by appropriate methods such as Bradford, BAPNA (N-benzoyl-1-arginine-p-nitroanilide), and BSA (Bovine Serum Albumin). Enzymatic processes were carried out for 24 h in the incubator set at 40 C, 100 rpm, and specified pH with 1 mg/ml enzyme concentration. Whiteness index (Stensby) and yellowness index (ASTM D 1925) were examined after enzymatic pretreatment. Pepsin and trypsin-treated wool fibres showed the highest whiteness index as 61.3 and 61.1, respectively whilst untreated wool fibres had 52.2. Fourier-transform infrared (FTIR) analysis revealed the increase in the intensity of amide-related bands and hydroxyl bands after enzymatic treatment.Scanning electron microscopy (SEM) photomicrographs manifested the cuticle layer is partially removed in enzyme-treated fibres. Elemental identification was provided by SEM-energy-dispersive X-ray spectroscopy (EDX). It appears that the sulphur bonds decreased after the treatment and the pepsin-treated fibres have fewer bonds of all. To examine the damage to the structure, photomicrographs were taken using fluorescence and light microscopes. The alkali solubility test (ASTM D1283) was also conducted to compare different enzyme types. Wool fibres were dyed in 2.0% concentration with reactive dyestuff. Dyeability and colorimetric features of fibres were measured by a spectrophotometer. The washing fastness test showed that all the samples have good results and the colour change after washing was better in enzyme-treated samples (grade 5) compared to untreated wool fibres (grade 4-5).

The effect of a novel catalytic system with Savinase 16L and an organophosphine compound on the shrink-proofing and dyeing properties of wool

“…14,19 Compared with the existing enzyme treatment studies, the protease catalytic system process is characterized by high efficiency, short treatment time, ease of operation, and can be processed continuously. [29][30][31][32] Its treatment efficiency is similar to the traditional chlorination treatment, and the shrinkage prevention effect is better than that of chlorination treatment. 32 Furthermore, it has the characteristic of ecological safety.…”

Whole Genome Resequencing Reveals Selection Signals Related to Wool Color in Sheep

“…Breeding for white wool has always been a priority in sheep farming, due to the high level of pursuit by the textile industry [1,3,5,8,9]. And, with the rise of green concept [3,10,11], natural colored wool is a way to replace traditional printing and dyeing [12]. A comparison of modern and ancient wool products reveals a reduction in the diversity of modern wool colors [5,13], making it imperative to conserve colored wool breeding resources.…”

ICONTEX and ICONWOOLF 2022 Special Issue

“…The subject of two articles in this special issue is an examination of the effects of enzymatic processes on various properties of wool fibres, including dyeability. Dr. Gizem Ceylan Türkoğlu and her colleagues, 1 and Ms. Berrak Buket Avcı and Dr. Gökhan Erkan, 2 from Dokuz Eylül University, Turkey, demonstrate the results of pretreatment with protease and glucose oxidase enzymes, respectively. In both studies, it was revealed that enzymatic pretreatment increased dye uptake and resulted in a higher colour yield than the untreated samples.…”