title: Biotransformation of ferulic acid to vanillin in the packed bed-stirred fermentors.
abstract: We performed the biotransformation of ferulic acid to vanillin using Bacillus subtilis (B. subtilis) in the stirring packed-bed reactors filled with carbon fiber textiles (CFT). Scanning electron microscope (SEM), HPLC, qRT-PCR and ATP assay indicated that vanillin biotransformation is tightly related to cell growth, cellar activity and the extent of biofilm formation. The biotransformation was affected by hydraulic retention time (HRT), temperature, initial pH, stirring speed and ferulic acid concentration, and the maximum vanillin production was obtained at 20 h, 35 °C, 9.0, 200 rpm, 1.5 g/L, respectively. Repeated batch biotransformation performed under this optimized condition showed that the maximum productivity (0.047 g/L/h) and molar yield (60.43%) achieved in immobilized cell system were 1.84 and 3.61 folds higher than those achieved in free cell system. Therefore, the stirring reactor packed with CFT carrier biofilm formed by B. subtilis represented a valid biocatalytic system for the production of vanillin.
authors.affiliation: College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Xinfeng Road No.5, Daqing, 163319, P.R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Yan
authors.affiliation: School of Pharmacy, Lanzhou University, Donggang West Road No. 199, Lanzhou, 730020, P.R. China.
authors.forename: Peng
authors.initials: P
authors.lastname: Chen
authors.affiliation: College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Xinfeng Road No.5, Daqing, 163319, P.R. China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Gansu Institute of Business and Technology, Yannan Road No. 449, Lanzhou, 730010, P.R. China.
authors.forename: Suyue
authors.initials: S
authors.lastname: Li
authors.affiliation: Gansu Institute of Business and Technology, Yannan Road No. 449, Lanzhou, 730010, P.R. China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Yan
authors.affiliation: Gansu Institute of Business and Technology, Yannan Road No. 449, Lanzhou, 730010, P.R. China.
authors.forename: Ningbo
authors.initials: N
authors.lastname: Wang
authors.affiliation: Gansu Institute of Business and Technology, Yannan Road No. 449, Lanzhou, 730010, P.R. China.
authors.forename: Ning
authors.initials: N
authors.lastname: Liang
authors.affiliation: School of Pharmacy, Lanzhou University, Donggang West Road No. 199, Lanzhou, 730020, P.R. China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Li
mesh_terms: D001412:Bacillus subtilis / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000379:methods; D001547:Benzaldehydes / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors; D001711:Biotransformation; D002244:Carbon / Q000737:chemistry; D000077482:Carbon Fiber; D018914:Cells, Immobilized / Q000378:metabolism*; D003373:Coumaric Acids / Q000378:metabolism*; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D013696:Temperature; D013784:Textiles
chemical_list: D001547:Benzaldehydes; D000077482:Carbon Fiber; D003373:Coumaric Acids; D002244:Carbon; C004999:ferulic acid; C100058:vanillin