Immobilization of pectinase on the glass bead using polyaldehyde kefiran as a new safe cross-linker and its effect on the activity and kinetic parameters

Seyed Saeid Hosseini; Faramarz Khodaiyan; Seyed Mohammad E Mousavi; Seyedeh Zahra Azimi; Mohammad Gharaghani

doi:10.1016/j.foodchem.2019.125777

Immobilization of pectinase on the glass bead using polyaldehyde kefiran as a new safe cross-linker and its effect on the activity and kinetic parameters

Food Chem. 2020 Mar 30:309:125777. doi: 10.1016/j.foodchem.2019.125777. Epub 2019 Oct 25.

Authors

Seyed Saeid Hosseini¹, Faramarz Khodaiyan², Seyed Mohammad E Mousavi¹, Seyedeh Zahra Azimi¹, Mohammad Gharaghani¹

Affiliations

¹ Bioprocessing and Biodetection Laboratory, Department of Food Science and Engineering, University of Tehran, Karaj 31587-77871, Iran.
² Bioprocessing and Biodetection Laboratory, Department of Food Science and Engineering, University of Tehran, Karaj 31587-77871, Iran. Electronic address: khodaiyan@ut.ac.ir.

PMID: 31699560
DOI: 10.1016/j.foodchem.2019.125777

Abstract

For the first time, polyaldehyde kefiran was applied to immobilize the pectinase on the glass bead and the finding was compared with free enzyme. Polyaldehyde kefiran, produced by periodate oxidation of kefiran, showed an aldehyde content of 23.6 ± 0.9% that was confirmed by FTIR. The results showed although the optimum temperature (50 °C) was not changed by immobilization, the optimum pH was shifted from 5.0 to 5.5. In optimal conditions, the specific activity of the free and immobilized pectinase was 2.93 ± 0.13 and 1.87 ± 0.24 unit/mg, respectively. Also, the immobilized pectinase had a higher thermal and pH stability than free enzyme. K_m and V_max of the immobilized pectinase were higher and lower than the free enzyme, respectively. In addition, SEM and AFM images illustrated a completely non-uniform surface after enzyme immobilization on the glass bead, which seemed to be related to the polyaldehyde kefiran strands.

Keywords: Glass bead; Immobilization; Kinetic parameters; Pectinase; Polyaldehyde kefiran.

MeSH terms

Enzyme Stability
Enzymes, Immobilized / chemistry
Enzymes, Immobilized / metabolism
Hydrogen-Ion Concentration
Kinetics
Microscopy, Atomic Force
Microscopy, Electron, Scanning
Oxidation-Reduction
Polygalacturonase / chemistry
Polygalacturonase / metabolism*
Polysaccharides / chemistry*
Temperature

Substances

Enzymes, Immobilized
Polysaccharides
kefir grain polysaccharide
Polygalacturonase