Submitted to: Textile Research Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/27/2011
Publication Date: 5/1/2012
Citation: Slopek, R.P., Condon, B.D., Sawhney, A.P., Reynolds, M.L., Allen Jr, H.C. 2012. Effect of cotton pectin content and bioscouring on alkyl-dimethyl-benzyl-ammonium chloride adsorption. Textile Research Journal. 82(17):1743-1750. Interpretive Summary: Previous work showed greige cotton nonwovens adsorb a greater amount ADBAC at a faster rate than cotton nonwovens of a similar density that have been scoured and bleached. One explanation offered for this unexpected observation was the presence of pectin, a complex polysaccharide containing carboxylate side chains known to strongly interact with cationic surfactants, in the greige cotton nonwoven. In this study, we examine the use of an alkaline pectinase to remove pectin from greige cotton nonwovens via the environmentally-friendly process of bioscouring. Analysis of nonwoven fabrics dyed with Ruthenium Red showed that greige cotton nonwoven samples contained a considerable amount of pectin; however, treating these samples with an alkaline pectinase significantly reduced the amount of pectin in the samples. The optimal bioscouring process conditions were found to be pH of 8.5, a temperature of 55 °C, and an incubation time of 90 minutes. Under these conditions, the amount of pectin removed from the greige cotton nonwoven fabrics was equivalent to that removed by the traditional scouring and bleaching procedures. Pretreatment of greige cotton nonwovens with pectate lyase was found to significantly reduce the amount of ADBAC exhausted from the bulk solution. Using partial scouring via traditional and pectinase-based methods, the adsorption of ADBAC onto cotton nonwovens was found to linearly dependent on the amount of pectin in present in the fabric. Although the presence of waxes on gregie cotton was shown to play a role in the adsorption of ADBAC, it was minor compared to the effect of pectin. It is important to note that the results and conclusions of this research are expected to be generally applicable to all forms of cotton, not just nonwovens. This work opens the door to the possible development of a greige cotton-based disposable antimicrobial.
Technical Abstract: Our previous research has shown both the rate and the total amount of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC) exhausted from a bulk solution of ADBAC are significantly greater for greige cotton nonwovens than cotton nonwovens that have been both scoured and bleached. The presence of pectin in greige cotton samples was offered as one of the possible explanation for this observed phenomenon. To elucidate the effect of pectin and cotton’s natural waxes on the adsorption of ADBAC on greige cotton nonwovens, low-weight greige nonwovens were bioscoured with a pectate lyase prior to being immersed in aqueous solutions of ADBAC. The eco-friendly scouring process was optimized for greige cotton nonwovens and the optimal process parameters were as follows: pH of 8.5, temperature of 55 °C, and an incubation time of 90 minutes. Under these conditions, the amount of pectin removed from the fabrics was equivalent to that removed by traditional scouring and bleaching procedures. Pretreatment of greige cotton nonwovens with pectate lyase was found to significantly reduce the about of amount of ADBAC exhausted from the bulk solution. Through partial scouring via traditional and pectinase-based methods, the adsorption of ADBAC onto cotton nonwovens was found to linearly dependent on the amount of pectin in present in the fabric. Both waxes and pectin were found to play an important role in ADBAC adsorption; however, the observed effect of pectin was significantly greater than cotton’s natural waxes.