ARS | Publication request: Ion binding capacity of enzyme modified citrus peel and pectin

Submitted to: Subtropical Technology Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: September 15, 2007
Publication Date: October 18, 2007
Citation: Cameron, R.G., Luzio, G.A., Widmer, W.W., Iqbal, M. 2007. Ion binding capacity of enzyme modified citrus peel and pectin. Subtropical Technology Conference Proceedings. 58:19.

Technical Abstract: A wide ranging group of enzyme modified pectin and polygalacturonic acid (PGA) samples were tested for their biosorption potential, specifically their ability to bind Pb. Two sample sets were the pH 4.5 and 7.5 demethylated series obtained from demethylation of a model homogalacturonan produced using the Citrus salt-independent PME. Another group of samples consisted of either commercially available pectin or laboratory extracted pectin (both total pectin and non calcium sensitive pectin; peel particles still present) that were demethylated with a commercially available plant extract. A third set of samples were three different narrow range size-classes of PGA produced by differential precipitation of a limited endo polygalacturonase digest of PGA. The final sample tested was the peel hydrolysate produced during the conversion of citrus peel to ethanol. The highest biosorption capacity was observed in the narrow range size classes produced from PGA. Although significant differences were observed among the three size-classes, all had a greater capacity than any of the other samples. Block demethylation of commercial pectin with a commercial plant extract was the closest sample to the PGA size-classes. However, all samples tested were able to remove the heavy metal ion from the solution in significant quantities.