title: Thermal Destabilization of Rhizomucor miehei Rennet with Aldehyde Dextran Sulfate: Purification, Bioconjugation and Milk-Clotting Activities.
abstract: High thermal stability of Rhizomucor miehei Rennet, which is a thermostable enzyme used in cheese production, causes undesired cases at elevated temperatures. This study aims to decrease the thermal stability of the R. miehei Rennet at high temperatures. To achieve this goal, bioconjugates of R. miehei Rennet with aldehyde derivative of dextran sulfate were synthesized in different molar ratios. Physico-chemical properties of bioconjugates were characterized with particle size analyzer and gel permeation chromatography (GPC) techniques. The enzyme and biopolymer were conjugated with medium efficiency. Milk-clotting activities of bioconjugates decreased drastically at high temperatures in all molar ratios, which reveals that covalent bioconjugation of the enzyme with aldehyde derivative of dextran sulfate caused a decrease in thermal resistance of this enzyme.
authors.affiliation: Faculty of Engineering, Department of Polymer Engineering, Yalova University, 77100, Yalova, Turkey. mithat.celebi@yalova.edu.tr.
authors.forename: Mithat
authors.initials: M
authors.lastname: Celebi
authors.affiliation: Faculty of Chemical and Metallurgical Engineering, Department of Bioengineering, Yıldiz Technical University, 34210, Istanbul, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Topuzogullari
authors.affiliation: Faculty of Chemical and Metallurgical Engineering, Department of Bioengineering, Yıldiz Technical University, 34210, Istanbul, Turkey.
authors.forename: Huriye
authors.initials: H
authors.lastname: Kuzu
mesh_terms: D000447:Aldehydes / Q000494:pharmacology*; D000818:Animals; D012085:Chymosin / Q000378:metabolism*; D016264:Dextran Sulfate / Q000494:pharmacology*; D004795:Enzyme Stability / Q000187:drug effects; D006358:Hot Temperature; D057446:Hydrodynamics; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000737:chemistry*; D010316:Particle Size; D020103:Rhizomucor / Q000201:enzymology*
chemical_list: D000447:Aldehydes; C025350:rennet; D016264:Dextran Sulfate; D012085:Chymosin
keywords: Bioconjugation; Dextran sulfate; Milk-clotting activity; Purification; Rhizomucor miehei Rennet; Thermal destabilization