College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Xinfeng Road No.5, Daqing, 163319, P.R. China.
School of Pharmacy, Lanzhou University, Donggang West Road No. 199, Lanzhou, 730020, P.R. China.
Sci Rep. 2016 Oct 6;6:34644. doi: 10.1038/srep34644.
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.
我们使用枯草芽孢杆菌（B. subtilis）在填充碳纤维纺织品（CFT）的搅拌填充床反应器中进行阿魏酸到香草醛的生物转化。扫描电子显微镜（SEM）、高效液相色谱（HPLC）、qRT-PCR 和 ATP 测定表明，香草醛的生物转化与细胞生长、细胞活性和生物膜形成程度密切相关。生物转化受水力停留时间（HRT）、温度、初始 pH 值、搅拌速度和阿魏酸浓度的影响，分别在 20 h、35°C、9.0、200 rpm 和 1.5 g/L 时获得最大香草醛产量。在优化条件下进行的重复分批生物转化表明，固定化细胞体系的最大生产力（0.047 g/L/h）和摩尔收率（60.43%）分别比游离细胞体系高 1.84 倍和 3.61 倍。因此，由枯草芽孢杆菌形成的 CFT 载体生物膜填充搅拌反应器是生产香草醛的有效生物催化系统。
