title: Stabilization by multipoint covalent attachment of a biocatalyst with polygalacturonase activity used for juice clarification.
abstract: Derivatized-agarose supports are suitable for enzyme immobilization by different methods, taking advantage of different physical, chemical and biological conditions of the protein and the support. In this study, agarose particles were modified with MANAE, PEI and glyoxyl groups and evaluated to stabilize polygalacturonase from Streptomyces halstedii ATCC 10897. A new immobilized biocatalyst was developed using glyoxyl-agarose as support; it exhibited high performance in degrading polygalacturonic acid and releasing oligogalacturonides. Maximal enzyme activity was detected at 5h of reaction using 0.05g/mL of immobilized biocatalyst, which released 3mg/mL of reducing sugars and allowed the highest product yield conversion and increased stability. These results are very favorable for pectin degradation with reusability up to 18 successive reactions (90h) and application in juice clarification. Plum (4.7°Bx) and grape (10.6°Bx) juices were successfully clarified, increasing reducing sugars content and markedly decreasing turbidity and viscosity.
authors.affiliation: Sustainable Biotechnology Laboratory (LIBioS), National University of Quilmes, Roque Sáenz Peña 352, Bernal B1876BXD, Argentina.
authors.forename: Yuly A
authors.initials: YA
authors.lastname: Ramírez Tapias
authors.affiliation: Sustainable Biotechnology Laboratory (LIBioS), National University of Quilmes, Roque Sáenz Peña 352, Bernal B1876BXD, Argentina.
authors.forename: Cintia W
authors.initials: CW
authors.lastname: Rivero
authors.affiliation: Heterogeneous Biocatalysis Group, CIC Biomagune, Edificio Empresarial "C", Paseo Miramón 182, Donostia-San Sebastián 20009, Spain; Ikerbasque, Basque Foundation for Science, Alda. Urquijo, Urkixo Zumarkalea 36, Bilbao 48011, Spain.
authors.forename: Fernando López
authors.initials: FL
authors.lastname: Gallego
authors.affiliation: Institute of Catalysis and Petrochemistry (ICP-CSIC), Campus UAM-Cantoblanco, Madrid 28049, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Guisán
authors.affiliation: Sustainable Biotechnology Laboratory (LIBioS), National University of Quilmes, Roque Sáenz Peña 352, Bernal B1876BXD, Argentina. Electronic address: jtrelles@unq.edu.ar.
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Trelles
mesh_terms: D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D005511:Food Handling / Q000379:methods*; D005638:Fruit / Q000737:chemistry / Q000201:enzymology; D000067030:Fruit and Vegetable Juices / Q000032:analysis*; D006038:Glyoxylates / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D010368:Pectins / Q000378:metabolism*; D011096:Polygalacturonase / Q000737:chemistry / Q000378:metabolism*; D000068242:Prunus domestica / Q000737:chemistry / Q000201:enzymology; D012685:Sepharose / Q000737:chemistry*; D027843:Vitis / Q000737:chemistry / Q000201:enzymology
chemical_list: D004800:Enzymes, Immobilized; D006038:Glyoxylates; C070399:glyoxyl agarose; D010368:Pectins; D012685:Sepharose; D011096:Polygalacturonase; C003181:polygalacturonic acid
keywords: Enzyme purification; Glyoxyl-agarose; Grape and plum juices; Streptomyces halstedii ATCC 10897