Immobilization of halophilic Bacillus sp. EMB9 protease on functionalized silica nanoparticles and application in whey protein hydrolysis.
The present work targets the fabrication of an active, stable, reusable enzyme preparation using functionalized silica nanoparticles as an effective enzyme support for crude halophilic Bacillus sp. EMB9 protease. The immobilization efficiency under optimized conditions was 60%. Characterization of the immobilized preparation revealed marked increase in pH and thermal stability. It retained 80% of its original activity at 70 °C while t 1/2 at 50 °C showed a five-fold enhancement over that for the free protease. Kinetic constants K m and V max were indicative of a higher reaction velocity along with decreased affinity for substrate. The preparation could be efficiently reused up to 6 times and successfully hydrolysed whey proteins with high degree of hydrolysis. Immobilization of a crude halophilic protease on a nanobased scaffold makes the process cost effective and simple.
Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi, 110016, India.
Rajeshwari
R
Sinha
S K
SK
Khare
D001407:Bacillus / Q000201:enzymology*; D003432:Cross-Linking Reagents / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007218:Industrial Microbiology; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry; D010447:Peptide Hydrolases / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D000067796:Whey; D000067816:Whey Proteins / Q000737:chemistry
D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D000067816:Whey Proteins; D012822:Silicon Dioxide; D010450:Endopeptidases; D010447:Peptide Hydrolases