Repeated Batch Biotransformation from Isoeugenol to Vanillin by Immobilized Bacillus fusiformis Cells in CSTR Reactor

Bacillus fusiformis CGMCC1347, screened from soil, was immobilized successfully to biotransform isoeugenol to vanillin. The optimal immobilization conditions were 2.5% sodium alginate, 10% cell density and Ca2+ 0.1 mol l-1. The optimal reaction conditions in a 2 L CSTR reactor with immobilized Bacillus fusiformis CGMCC1347 cells were isoeugenol 600 mL, immobilized cells 400 g, pH 3.5 dH2O 400 mL, 37 oC, 200 r min-1 shaking speed and 0.8 vvm air capacity. The average vanillin concentration reached 39.26 g l-1 after 6 times reuse of immobilized cells in 2 L CSTR.