title: Optimization of alpha-amylase immobilization in calcium alginate beads.
abstract: alpha-Amylase enzyme was produced by Aspergillus sclerotiorum under SSF conditions, and immobilized in calcium alginate beads. Effects of immobilization conditions, such as alginate concentration, CaCl(2) concentration, amount of loading enzyme, bead size, and amount of beads, on enzymatic activity were investigated. Optimum alginate and CaCl(2) concentration were found to be 3% (w/v). Using a loading enzyme concentration of 140 U mL(-1), and bead (diameter 3 mm) amount of 0.5 g, maximum enzyme activity was observed. Beads prepared at optimum immobilization conditions were suitable for up to 7 repeated uses, losing only 35% of their initial activity. Among the various starches tested, the highest enzyme activity (96.2%) was determined in soluble potato starch hydrolysis for 120 min at 40 degrees C.
authors.affiliation: Faculty of Science and Art, Department of Biology, Trakya University, Edirne, Turkey. fertan@trakya.edu.tr
authors.forename: Figen
authors.initials: F
authors.lastname: Ertan
authors.forename: Hulya
authors.initials: H
authors.lastname: Yagar
authors.forename: Bilal
authors.initials: B
authors.lastname: Balkan
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry*; D001230:Aspergillus / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008863:Microspheres; D013213:Starch / Q000737:chemistry; D013696:Temperature; D000516:alpha-Amylases / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000464:Alginates; D003470:Culture Media; D004800:Enzymes, Immobilized; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D013213:Starch; D000516:alpha-Amylases