Development of a Novel Wet Process Technique of Cotton Knit Fabric for Textile Applications

Abstract

The purpose of this thesis was to develop a novel wet process technique for textile applications, which was accomplished with the production and implementation of natural and recombinant bacterial species having pectinolytic activities, assessed their pectinolytic activity both qualitatively and quantitatively, as well as compared with commercial pectinase enzyme for checking its bio scouring efficiency. Recombinant DNA technology was applied to produce pectinase enzymes and natural pectinase enzymes were produced from the source of chia seeds and soil mixture. Ten synthesized gene fragments were amplified in a PCR machine and ligated gene length was checked by electrophoresis gel run with a ladder to confirm their expected size. Successful transformation of fungal pectinase gene into bacterial plasmid DNA was accomplished to produce recombinant pectinase enzyme with their positive pectinolytic activity test results by iodine and DNS. Plasmid extraction for gene length checking was matched with the gene length of interest which was ~ 1143 bps and protein molecular weight was ~ 38 KDa which was found by PAGE run. Here two types of bacterial species DH5 and BL21 were used for gene transformation. Cotton knit fabric bio-scoured samples with these enzymes’ application were checked for wicking test, whiteness index, colour difference, FTIR analysis, SEM, and bursting strength tests. The wicking rate of recombinant DH5, BL21, and natural enzymes in the cotton knit fabric scoured sample was found 85 mm, 65 mm, and 55 mm after ten minutes, and K/S was 14.5, 14.7, and 14.8 after dyeing with DH5, BL21 and natural enzyme-treated fabric respectively. The findings disclosed that DH5 had superior scouring performance in cotton knit fabrics among produced enzymes that worked at 37 C, an energy-saving process, and pectinolytic activity was nearer to commercial enzymes which had recommended a bio-scouring temperature of 60 C. Burkholderia cepacia, a natural bacterial species, showed its better pectinolytic activity comparable with commercially available pectinase enzymes in the textile industry. In the thesis, an attempt was made to increase the whiteness of bio-scoured fabric for oxidative bleaching with hydrogen peroxide and reductive bleaching with sodium borohydride and the values are 61.15, 58.14, 59.72. for CS, BL, and D8 bio-scoured fabric respectively, and compared with chemical-scoured bleached fabric's whiteness which was 64. After dyeing, the chemically scoured bleached dyed sample showed a lightness value of 25.61 for the dark navy and 89.48 for the light-yellow colour. The lightness values were 24.63, 24.75, 26.40 for the dark navy colour, and 88.37, 88.14, and 88.09 for the light-yellow colour of bio-scoured natural, BL21, and DH5 bleached fabric respectively. Thus, light colour, as well as dark colour, can be dyed with low-temperature processed bio-scoured fabric.