TITLE:
Bovine Bone Charcoal as Support Material for Immobilization of Bacillus firmus Strain 37 and Production of Cyclomaltodextrin Glucanotransferase by Batch Fermentation in a Fluidized Bed
AUTHORS:
Larissa Albunio Silva, Bruno Cesar Bieli, Osvaldo Valarini Junior, Graciette Matioli, Gisella Maria Zanin, Flavio Faria Moraes
KEYWORDS:
Bacillus firmus, Bone Charcoal Matrix, Cell Immobilization, Microbial Enzyme, Cyclomaltodextrin Glucanotransferase
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.8 No.1,
January
31,
2018
ABSTRACT: The process described in the present work uses air supplementation in a fluidized
bed reactor containing Bacillus firmus strain 37 immobilized on active
bovine bone charcoal, to produce by batch fermentation the enzyme CGTase
(cyclomaltodextrin-glucanotransferase). Three different aeration rates were
evaluated. The maximum CGTase activity was achieved after 120 hours of
fermentation with aeration rate of 2 vvm and was equal to 2.48 U/mL. When
0.5 and 1 vvm were used the enzymatic activities achieved 1.1 and 0.57 U/mL,
respectively. Bovine bone charcoal was characterized in terms of surface area,
pore size and volume. To the best of our knowledge, the immobilization of
microorganism cells in bovine bone charcoal for CGTase production has not
been reported in the literature. Our results showed that fluidized bed reactor
allows retaining high concentration of biomass, improving biomass-substrate
contact and operation at low residence times, which resulted in improved enzyme
production. Therefore, the process as proposed has great potential for
industrial development.