The solubility of primary plant cell wall polysaccharides in LiCl-DMSO.

In order to understand the architecture of the primary plant cell wall, knowledge on its polysaccharides and their interactions is of importance. In this study, further architectural insight was obtained by sequential LiCl-DMSO and buffer extractions after planetary ball milling. After milling, up to 50% of all polysaccharides in the Chelating agent Unextractable Solids (ChUS) from carrot, tomato and strawberry solubilised in LiCl-DMSO without loss of structural information.

Characterisation of pectin-xylan complexes in tomato primary plant cell walls.

The primary plant cell wall is composed of a complex network of pectin, hemicellulose and cellulose. Potential interactions between these polysaccharides were studied for carrot, tomato and strawberry, with a focus on the role of pectin. The Chelating agent Unextractable Solids (ChUS), the residue after water- and EDTA extraction, was ball milled and subsequently water extracted.

Interactions between pectin and cellulose in primary plant cell walls.

To understand the architecture of the plant cell wall, it is of importance to understand both structural characteristics of cell wall polysaccharides and interactions between these polysaccharides. Interactions between polysaccharides were studied in the residue after water and chelating agent extraction by sequential extractions with HO and alkali. The 6 M alkali residue still represented 31%, 11% and 5% of all GalA present in carrot, tomato and strawberry, respectively, and these pectin populations were assumed to strongly interact with cellulose.

Acetylated pectins in raw and heat processed carrots.

Heat processing results in softening of carrots, changing the pectin structure. The effect of heat processing on pectin was studied, showing that the amount of pectin in water soluble solids (WSS) and chelating agent soluble solids (ChSS) increased substantially upon heat processing of the carrots. Pectin in WSS from both unprocessed and heat processed carrot had a degree of methyl-esterification (DM) of ≈60% and a degree of acetylation (DA) of ≈20%.