Once again food gums come to the rescue of our building project.
This time – sodium alginate.
Here an I applying a slurry of a 2% (w/w) alginate solution containing peat moss, compost, and grass seeds to a newly exposed cut at the back of our driveway.
The alginate forms a gel slowly in-situ using the Ca2+ from the soil, and we found out, from the peat moss. It seems to bind the soil and retains moisture for the seeds.
The alginates gel more strongly if there are more “G” or guluronate blocks than “M” or mannuronate blocks based on a variant of the ion-mediated “egg-box” junction zones of a similar nature to those found in low- methoxy pectins.
Other polysaccharides with ability to bind soil exist, possibly the most unusual one being the gums of a “new” polysaccharide complex from the seeds of “Artemisia sphaerocephala” in the family Asterceae. A sphaerocephala is thought to have pectin-like polymers with arabinogalactan side chains and the putative presence of a 4-O-Methyl glucuronoxylan which is considered to be bioactive (Batbayar et al., 2008).
In contrast Zhang et al. (2007) reported onlythe presence of arabinose, xylose, lyxose, mannose, glucose, and d-galactose but no acidic monosaccharides.
The reported ability of A sphaerocephala gum to improve chewing quality and elasticity in noodles (Xing et al., 2009) may suggest an anionic polymer with gelling capabilities similar to alginate or low-methoxy pectins. A sphaerocephala gum is reputed to be effective against diabetes and has a clinical record in animal studies to support that conjecture (e.g. (Xing et al., 2009).
Soil? A sphaerocephala gum also has the interesting property of being able to aggregate sandy soil (Batbayar et al., 2008).
BATBAYAR, N., BANZRAGCH, D., INNGJERDINGEN, K. T., NARAN, R., MICHAELSEN, T. E. & PAULSEN, B. S. 2008. Polysaccharides from Mongolian plants and their effect on the complement system: I. Polysaccharides from plants of the Asteraceae family. Asian Journal of Traditional Medicines, 3, 33-41.
ZHANG, J., WU, J., LIANG, J., HU, Z., WANG, Y. & ZHANG, S. 2007. Chemical characterization of Artemisia seed polysaccharide. Carbohydrate Polymers, 67, 213-218.