WOLMAN Federico Javier
congresos y reuniones científicas
New affinity chromatographyc matriz for glycomacropeptide purification
MARÍA FERNANDA BAIELI; OSVALDO CASCONE; FEDERICO J. WOLMAN
Congreso; SAIB 2012, 48 Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2012
Aim The aim of this work was the development of a novel affinity chromatographic matrix for glycomacropeptide (GMP) purification. Based on the affinity of the wheat germ agglutinin (WGA) for sialic acid and having the GMP high levels of this sugar (7-8%), the developed matrices consisted of mini-spheres of chitosan cross-linked with epichlorohydrin with immobilized WGA as affinity ligand. Methods Matrices were obtained by dripping a 2%chitosan solution in acetic acid (2 or 4%) on 2M NaOH and were cross-linked with 250 mM epichlorohydrin. For WGA adsorption a wheat germ aqueous extract was used. Preliminary GMP adsorption conditions were tested at pH 4, 5, 7 and 8.5 with pure GMP solutions. Adsorption isotherms were performed at pH 7 and 8.5. Sixteen different eluents were tested. Results At pH 4 and 5 did not show a significant binding of GMP to matrices. At pH 7 and 8.5 adsorption was similar. The GMP maximum adsorption capacity for different matrices at pH 7 was between 137.0 and 57.1 mg/g and at pH 8.5 was between 149.4 and 79.1 mg/g. The best eluent was 1M glucosamine. Conclusions We have synthesized chromatographic matrices based on chitosan that after adsorption and cross-linking of WGA, showed optimal adsorption and elution for pure GMP. Therefore, the developed matrices are a promising application for GMP purification from cheese whey increasing its added value.