title: Selective recovery of glycosylated caseinmacropeptide with chitosan.
abstract: The use of chitosan, a partially deacetylated chitin, to fractionate aqueous solutions of caseinmacropeptides (CMPs) was studied. The polycationic character of chitosan at acidic pH values allows the formation of complexes with negatively charged CMP molecules, inducing their flocculation. Glycosylated CMP (GMP) has higher affinity for chitosan than nonglycosylated forms (NGMP). The carboxylic groups in the carbohydrate moiety of the GMP increase the negative charge of the molecule and may play a role in the selective precipitation. At pH 5.0, 0.08 mg/mL of chitosan completely removed the GMP whereas 70% of NGMP remained in solution. As the pH increased, the amount of chitosan to ensure complete removal of GMP increased up to 0.19 and 0.34 mg/mL for pH 6.0 and 6.6, respectively.
authors.affiliation: Instituto de Fermentaciones Industriales (C.S.I.C.), C/ Juan de la cierva 3, 28006 Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Casal
authors.forename: N
authors.initials: N
authors.lastname: Corzo
authors.forename: F J
authors.initials: FJ
authors.lastname: Moreno
authors.forename: A
authors.initials: A
authors.lastname: Olano
mesh_terms: D002364:Caseins / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D011232:Chemical Precipitation; D048271:Chitosan / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D012085:Chymosin / Q000378:metabolism; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D009439:Neuraminidase / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry* / Q000302:isolation & purification*; D012996:Solutions
chemical_list: D002364:Caseins; D010446:Peptide Fragments; D012996:Solutions; C065989:caseinomacropeptide; D048271:Chitosan; D009439:Neuraminidase; D012085:Chymosin