ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Interaction of Moringa oleifera seed lectin with humic acid
Andréa F. S. Santos, Maria G. Carneiro-da-Cunha, José A. Teixeira, Patrícia M. G. Paiva, Luana C. B. B. Coelho, and Regina Nogueira
IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4705-057 Braga, Portugal
Abstract: The aim of this work was to characterise the affinity of protein preparations from Moringa oleifera seeds, specifically extract (seeds homogenised with 0.15 M NaCl), fraction (extract precipitated with 390 mg mL−1 of ammonium sulphate) and cMoL (coagulant M. oleifera lectin) to bind humic acids using a haemagglutinating activity assay with rabbit erythrocytes and a radial diffusion assay
in agarose gel. Specific haemagglutinating activity (SHA) decreased by 94 % for the extract and cMoL and by 50 % for the fraction
in the presence of humic acid. Precipitation bands were observed in the diffusion gel. Both results suggested humic acid-cMoL binding. Carbohydrates, potassium, and calcium ions and pH affected the SHA of cMoL. As an example of application, cMoL was immobilised on a column packed with sepharose receiving 20 mg mL−1 of carbon humic acid solution, 30 mg of humic acid per gram of support was removed. This result suggested that protein preparations
might be used in water treatment to remove humic acids.
Keywords: humic acid – lectin – Moringa oleifera – protein preparations – water treatment
Full paper is available at www.springerlink.com.
Chemical Papers 65 (4) 406–411 (2011)