Carbohydrate Polymers 99 (2014) 755–764 Contents lists available at ScienceDirect Carbohydrate Polymers jo ur nal homep age: www.elsevier.com/locate/carbpol Cationised O-acetyl galactoglucomannans: Synthesis and characterisation Victor Kisonen a,∗ , Chunlin Xu a,b , Patrik Eklund c , Hanna Lindqvist a , Anna Sundberg a , Andrey Pranovich a , Jari Sinkkonen d , Francisco Vilaplana b , Stefan Willför a a Process Chemistry Centre, c/o Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Porthansgatan 3-5, FI-20500, Turku/Åbo, Finland b Wallenberg Wood Science Center, KTH, the Royal Institute of Technology, Stockholm, Sweden c Laboratory of Organic Chemistry, Åbo Akademi University, Turku/Åbo, Finland d Department of Chemistry, University of Turku, Turku/Åbo, Finland a r t i c l e i n f o Article history: Received 18 March 2013 Received in revised form 2 September 2013 Accepted 4 September 2013 Available online xxx Keywords: Cationized Galactoglucomannans Hemicelluloses 13 C NMR MALDI-TOF-MS a b s t r a c t Water-soluble O-acetyl-galactoglucomannans (GGMs) can be obtained from Norway spruce by hot- water-extraction of the wood or as a side product by ultrafiltration of mechanical pulping waters. Cationic and amphiphilic polysaccharides and their derivatives are of interest for a number of applications and thus quaternary nitrogen moieties with cationic charge were grafted onto GGMs in the heterogeneous reaction to render a cationic polyelectrolyte. The degree of substitution was measured by elemental anal- ysis of nitrogen, by quantitative 13 C NMR and interestingly also by polyelectrolyte titration and the results were congruent. NMR, matrix-assisted laser desorption/ionisation mass spectroscopy (MALDI-TOF-MS), and FT-IR analysis were used to characterise the product. THF or DMSO with water enhanced the reaction efficiency and decreased M w reduction in comparison to plain water as a reaction media. Cationised GGM was also successfully acetylated. The cationic derivatives of hemicelluloses can potentially be utilised as polyelectrolyte layers in packaging and pharmaceutical applications. © 2013 Elsevier Ltd. All rights reserved. 1. Introduction O-acetyl-galactoglucomannans (GGMs) are the main hemi- celluloses in softwoods. Norway Spruce (Picea abies) GGM is a heteropolysaccharide and has a structure of randomly dis- tributed (1 → 4)-linked -d-mannopyranosyl and (1 → 4)-linked -d-glucopyranosyl units in the main chain, while (1 → 6)-linked -galactopyranosyl units are attached to mannose units only as side groups. O-acetyl groups are attached to C2 and C3 posi- tions of the mannose units in the main chain (Hannuksela and Hervé du Penhoat, 2004; Timell and Syracuse, 1967; Willför et al., 2003; Xu, Willför, Sundberg, Pettersson, & Holmbom, 2007). Norway spruce (P. abies) GGMs can be recovered from process waters in thermomechanical pulp mills by ultrafiltra- tion (Willför et al., 2003; Xu et al., 2007). Polymeric GGMs can also optionally be isolated from wood by hot-water extraction (Leppänen et al., 2011; Song, Pranovich, Sumerskiy, & Holmbom, 2008). There have been numerous efforts for utilising cationic polysac- charides and their derivatives. Cationised polysaccharides can be ∗ Corresponding author. Tel.: +358 40 5353979. E-mail address: vkisonen@abo.fi (V. Kisonen). used as flocculants in kaolin suspensions (Bratskaya et al., 2005; Sableviciene, Klimaviciute, Bendoraitiene, & Zemaitaitis, 2005; Tian, Wu, Liu, & Xie, 2010; Wei, Cheng, & Zheng, 2008) or they can be used as an alternative to polyacrylamide-based floccu- lants in waste water treatment and in papermaking (Kuutti et al., 2011). Physical properties of paper handsheets were improved significantly by adding cationised and carboxymethylated hemi- celluloses together, while using either of these alone, properties were improved less. Hemicelluloses may be used as the source for the production of wet-end additives in papermaking as a sustainable way of using the agricultural and forestry residues (Ren, Peng, Sun, & Kennedy, 2009). Small addition of cationised xylan in aqueous dispersion of thermomechanicalpulp increased retention by ∼3% (Ebringerova, Hromadkova, Kacurakova, & Antal, 1994). Adsorption of cationic polysaccharides and neutral polymers onto solid polymer surfaces has been compared to mimic the effect of hair conditioner on hair (Guzman et al., 2011). Cationic starch with adjusted charge density is used to adsorb water from rock surface pores in oil reservoirs (Leslie, Xiaoa, & Dong, 2005). Cationised konjac glucomannans showed inhibitory effects against some bacterial and fungal species (Yu, Huang, Ying, & Xiao, 2007). Chitooligosaccharide with quartenary ammonium group had antibacterial activity against the dental caries Steptocccus 0144-8617/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.carbpol.2013.09.009