Environmental pollution reducing strategy for scouring of undegummed sisal fibers using xylanase and pectinase enzymes

Abstract

This study was undertaken to investigate the potential of bioscouring in the processing of undegummed sisal fibers, using xylano-pectinolytic enzymes. Optimum bioscouring was obtained at pH 8.5 and 50 mM buffer molarity, using xylanase (10 IU) and pectinase (8 IU), with a material to liquor proportion of 1:25 (g:ml), EDTA (2 mM) and Tween 80 (0.5%), at 50 °C temperature with agitation rate of 55 rpm and treatment period of 60 min. Enzymatic treatment of sisal fibers enhanced the brightness and whiteness by 11.52 and 6.83%, respectively, and reduced the yellowness by 7.14% in comparison to control. The use of xylanase and pectinase enzymes completely replaced the chemical scouring method for removing non-cellulosic impurities. Thus, enzymatic scouring is energy saving and ecofriendly, since it completely eliminated the use of toxic chemicals used in alkaline scouring. An increase of 23.75% and 11.58% in brightness and whiteness of enzymatically scoured cum bleached fibers, as compared to chemically scoured cum bleached fibers was finally obtained, along with reduction in yellowness by 27.99%. This is the first report demonstrating environmentally sustainable enzymatic approach for scouring of undegummed sisal fibers, using enzymes, simultaneously produced from a bacterial isolate.

Keywords: Alkaline scouring; Bioscouring; Bleaching; Brightness; Whiteness; Yellowness.