Continuous degradation of maltose: improvement in stability and catalytic properties of maltase (α-glucosidase) through immobilization using agar-agar gel as a support

Bioprocess Biosyst Eng. 2015 Apr;38(4):631-8. doi: 10.1007/s00449-014-1302-6. Epub 2014 Oct 18.

Abstract

Maltose degrading enzyme was immobilized within agar-agar support via entrapment method due to its industrial utilization. The maximum immobilization efficiency (82.77%) was achieved using 4.0% agar-agar keeping the diameter of bead up to 3.0 mm. The matrix entrapment showed maximum catalytic activity at pH 7.0 and temperature 65 °C. Substrate saturation kinetics showed that the K m of immobilized enzyme increased from 1.717 to 2.117 mM ml(-1) where as Vmax decreased from 8,411 to 7,450 U ml(-1 )min(-1) as compared to free enzyme. The immobilization significantly increased the stability of maltase against various temperatures and immobilized maltase retain 100% of its original activity after 2 h at 50 °C, whereas the free maltase only showed 60% residual activity under same condition. The reusability of entrapped maltase showed activity up to 12 cycles and retained 50% of activity even after 5th cycle. Storage stability of agar entrapped maltase retain 73% of its initial activity even after 2 months when stored at 30 °C while free enzyme showed only 37% activity at same storage conditions.

MeSH terms

  • Agar / chemistry*
  • Bacillus / enzymology
  • Bioreactors*
  • Catalysis
  • Enzyme Stability
  • Enzymes, Immobilized / chemistry*
  • Hydrogen-Ion Concentration
  • Industrial Microbiology
  • Kinetics
  • Maltose / chemistry*
  • Microscopy, Electron, Scanning
  • Temperature
  • alpha-Glucosidases / chemistry*

Substances

  • Enzymes, Immobilized
  • Maltose
  • Agar
  • alpha-Glucosidases