Advertisement

Plant and Soil

, Volume 332, Issue 1–2, pp 319–330 | Cite as

Comparative hydrolysis and sorption of Al and La onto plant cell wall material and pectic materials

  • J. Bernhard Wehr
  • F. Pax C. Blamey
  • Peter M. Kopittke
  • Neal W. Menzies
Regular Article

Abstract

Pectin, which is an important component of plant cell walls, strongly binds Al and this may play a role in expression of Al toxicity. Sorption of aluminium (Al) and lanthanum (La) from aqueous solutions onto pectic acid, Ca-pectate and plant cell wall material was pH dependent. For Al at pH 3, sorption was less than the available sorption sites (i.e., the cation exchange capacity) on all three sorbents, whereas at pH 4, sorption of Al was in excess of available sorption capacity. By contrast, sorption of the trivalent Al analogue La corresponded to the available sorption capacity on all three sorbents at pH 5. This indicates, therefore, that Al hydrolyses at ≥ pH 4, and hydrolysis increases with Al concentration in solution. Further, it is proposed that the sorption of Al to pectin leads to deprotonation of the galacturonic acid (GalA) residues. Sorption of Al to pectin limits hydrolysis of Al, thereby shifting the pH of hydrolysis to a higher value. Hydrolysis of Al results in its sorption in excess of the stoichiometric equivalent (assuming the free Al3+ ion), leading to oversaturation of the pectin with Al. Staining of the metal-pectate complexes with the metachromatic dye eosin showed that with increasing Al saturation (but not La saturation), the complex developed a positive net charge, due to formation of some positively charged Al-complexes. The development of a positive charge on the Al-pectate complex may have major effects on cellular transmembrane potential and nutrient acquisition by plant roots. This is the first report of Al binding in excess of binding sites and development of a net positive charge on Al-pectate.

Keywords

Pectin Lanthanum Aluminum Adsorption Hydrolysis Metachromatic dyes Pectate 

Abbreviations

CEC

Cation exchange capacity

GalA

Galacturonic acid

ICPAES

Inductively coupled plasma atomic emission spectroscopy

Qmax

Sorption capacity

KL

Langmuir sorption constant

Notes

Acknowledgments

This research was supported under the Australian Research Council’s Discovery Projects funding scheme (project number DP 0665467), a UQ Ernest Singer Scholarship, and an Australian Government Overseas Research Postgraduate Scholarship.

References

  1. Blamey FPC, Dowling AJ (1995) Antagonism between aluminium and calcium for sorption by calcium pectate. Plant Soil 171:137–140CrossRefGoogle Scholar
  2. Blamey FPC, Asher CJ, Kerven GL, Edwards DG (1993) Factors affecting aluminium sorption by calcium pectate. Plant Soil 149:87–94CrossRefGoogle Scholar
  3. Blumenkrantz N, Asboe-Hansen G (1973) New method for the quantitative determination of uronic acids. Anal Biochem 54:484–489CrossRefPubMedGoogle Scholar
  4. Brett CT, Waldron KW (1996) Physiology and biochemistry of plant cell walls. Chapman & Hall, LondonGoogle Scholar
  5. Carpita NC, Gibeaut DM (1993) Structural models of primary cell walls in flowering plants: consistency of molecular structure with the physical properties of the walls during growth. Plant J 3:1–30CrossRefPubMedGoogle Scholar
  6. Conn H (1961) Biological stains. Williams and Wilkins Company, BaltimoreGoogle Scholar
  7. Dufey JE, Genon JE, Jaillard B, Calba H, Rufyikiri G, Delvaux B (2001) Cation exchange on plant roots involving aluminium: experimental data and modelling. In: Gobran GR, Wenzel WW, Lombi E (eds) Trace elements in the rhizosphere. CRC, Boca Raton, pp 228–250Google Scholar
  8. Food Chemical Codex (1972) National Academy of Sciences, WashingtonGoogle Scholar
  9. Franco CR, Chagas AP, Jorge RA (2002) Ion-exchange equilibria with aluminum pectinates. Colloids Surf, A 204:183–192CrossRefGoogle Scholar
  10. Furrer G, Trusch B, Muller C (1992) The formation of polynuclear aluminum under simulated natural conditions. Geochim Cosmochim Acta 56:3831–3838CrossRefGoogle Scholar
  11. Green F (1990) The Sigma-Aldrich handbook of stains, dyes and indicators. Aldrich Chemical Company, MilwaukeeGoogle Scholar
  12. Grignon C, Sentenac H (1991) pH and ionic conditions in the apoplast. Annu Rev Plant Physiol Plant Mol Biol 42:103–128CrossRefGoogle Scholar
  13. Jarvis MC (1984) Structure and properties of pectin gels in plant cell walls. Plant Cell Environ 7:153–164Google Scholar
  14. Jorge RA, Chagas AP (1984) Ionic exchange between aluminium pectinate and calcium, manganese, zinc, copper and iron(III) nitrates in aqueous solution. Quim Nova 7:179–180Google Scholar
  15. Jorge RA, Chagas AP (1988) Ion-exchange equilibria between solid aluminium pectinates and Ca, MnII, CuII and FeIII ions in aqueous solution. J Chem Soc, Faraday Trans 84:1065–1073CrossRefGoogle Scholar
  16. Kinniburgh DG (1986) General purpose adsorption isotherms. Environ Sci Technol 20:895–904CrossRefGoogle Scholar
  17. Kinraide TB, Yermiyahu U (2007) A scale of metal ion binding strengths correlating with ionic charge, Pauling electronegativity, toxicity, and other physiological effects. J Inorg Biochem 101:1201–1213CrossRefPubMedGoogle Scholar
  18. Meychik NR, Yermakov IP (2001) Ion exchange properties of plant root cell walls. Plant Soil 234:181–193CrossRefGoogle Scholar
  19. Meychik NR, Nikolaeva YI, Yermakov IP (2006) Ion-exchange properties of cell walls of Spinacia oleracea L. roots under different environmental salt conditions. Biochemistry-Moscow 71:781–789CrossRefPubMedGoogle Scholar
  20. Parkhurst DL, Appelo CAJ (1999) User’s guide to PHREEQC (Version 2)—a computer program for speciation, batch reaction, one-dimensional transport, and inverse geochemical calculations. In Water-Resources Investigations Report 99-4259, p 326. United States Geological Survey, Denver, COGoogle Scholar
  21. Postma J, Keltjens WG, van Riemsdijk WH (2005) Calcium-(organo)aluminum-proton competition for adsorption to tomato root cell walls: experimental data and exchange model calculations. Environ Sci Technol 39:5247–5254CrossRefPubMedGoogle Scholar
  22. Rufyikiri G, Genon JG, Dufey JE, Delvaux B (2003) Competitive adsorption of hydrogen, calcium, potassium, magnesium, and aluminum on banana roots: experimental data and modelling. J Plant Nutr 26:351–368CrossRefGoogle Scholar
  23. Sattelmacher B (2001) The apoplast and its significance for plant mineral nutrition. New Phytol 149:167–192CrossRefGoogle Scholar
  24. Wagatsuma T, Ezoe Y (1985) Effect of pH on ionic species of aluminum in medium and on aluminum toxicity under solution culture. Soil Sci Plant Nutr 31:547–561Google Scholar
  25. Wehr JB (1998) Reactions of cations with pectin and root cell walls. Ph.D. thesis, The University of QueenslandGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • J. Bernhard Wehr
    • 1
  • F. Pax C. Blamey
    • 1
  • Peter M. Kopittke
    • 1
    • 2
  • Neal W. Menzies
    • 1
    • 2
  1. 1.The University of Queensland, School of Land, Crop and Food SciencesSt LuciaAustralia
  2. 2.Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC-CARE)The University of QueenslandSt LuciaAustralia

Personalised recommendations