Grafting of aminated oligogalacturonans onto Douglas fir barks. A new route for the enhancement of their lead (II) binding capacities

Laboratoire de Chimie des Substances Naturelles, EA1069, Faculté des Sciences et Techniques, 123 avenue Albert Thomas, F-87060 Limoges, France.
Journal of hazardous materials (Impact Factor: 4.53). 10/2010; 182(1-3):279-85. DOI: 10.1016/j.jhazmat.2010.06.027
Source: PubMed


Chemical modification of Douglas fir bark and its subsequent utilization in adsorption of PbII from aqueous solutions was investigated. A new approach to enhance the natural properties of bark by covalent grafting of oligogalacturonans was developed. The polysaccharidic moiety of barks was functionalized by periodate oxidation and derivatized after reductive amination in presence of aminated oligogalacturonic acid. PbII adsorption isotherms of derivatized barks were then determined and compared with the capabilities of crude barks using the Langmuir adsorption model in terms of affinity (b) and maximum binding capacities (q(max)). Derivatization resulted in significant enhancements of the q(max) values (up to x8), along with little change of the affinity parameter.

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Available from: Céline Faugeron, May 20, 2014
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    • "Author's personal copy more than 20 kg Zn (Robinson et al. 2000; Vandecasteele et al. 2005; Yanai et al. 2006). Conifers are not widely studied for phytoaccumulation though they can be efficient (Cho et al. 1999; Martin- Dupont et al. 2006; Astier et al. 2010). Among them, larch has a fast growth rate, and deciduous needles which is very interesting to harvest the accumulated MTE. "
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    • "Recently , we demonstrated that the lead binding capacities of crude barks could be successfully increased through the covalent grafting of ami - nated oligogalacturonans ( Astier et al . 2010 ) or oligocarrageenans ( Astier et al . 2012 ) . Carboxylic acid functions , essentially found in pec - tin ( Khotimchenko et al . 2007 ; Kartel et al . 1999 ) are considered responsible for heavy metal binding through the phenomenon of ion exchange . Adsorption improvements have been obtained by increasing the number of accessible carb"
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