title: The Online Morphology Control and Dynamic Studies on Improving Vitamin B12 Production by Pseudomonas denitrificans with Online Capacitance and Specific Oxygen Consumption Rate.
abstract: The relationship between the morphological character of Pseudomonas denitrificans and vitamin B12 synthesis based on real-time capacitance measurement and online specific oxygen consumption rate (Q O2) control was established for enhancing vitamin B12 production. Results demonstrated that the threshold Q O2 value lower than 2.0 mmol/gDCW/l would greatly stimulate the state transfer from the cell number growth phase to the cell elongation phase and promote rapid vitamin B12 biosynthesis, while the vitamin B12 biosynthesis rate could also be inhibited when the rate of cell's length-to-width ratio (ratio-LW) was higher than 10:1. Furthermore, the optimal morphology controlling strategy was achieved based on online Q O2 control, which increases the appropriate active cell numbers at the former phase, and then control the elongation of ratio-LW no more than 10:1 at the vitamin B12 biosynthesis phase. The maximal vitamin B12 production reached 239.7 mg/l at 168 h, which was improved by 14.7 % compared with the control (208 mg/l). This online controlling strategy would be effectively applied for improving industrial vitamin B12 fermentation.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, Shanghai Institute of Biomanufacturing Technology & Collaborative Innovation Center, East China University of Science and Technology, P.O. Box 329, 130 Meilong Road, Shanghai, 200237, China. wangzejian@ecust.edu.cn.|Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628BC, Delft, The Netherlands. wangzejian@ecust.edu.cn.
authors.forename: Ze-Jian
authors.initials: ZJ
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Bioreactor Engineering, Shanghai Institute of Biomanufacturing Technology & Collaborative Innovation Center, East China University of Science and Technology, P.O. Box 329, 130 Meilong Road, Shanghai, 200237, China.
authors.forename: Hui-Lin
authors.initials: HL
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Bioreactor Engineering, Shanghai Institute of Biomanufacturing Technology & Collaborative Innovation Center, East China University of Science and Technology, P.O. Box 329, 130 Meilong Road, Shanghai, 200237, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
mesh_terms: D005285:Fermentation; D010101:Oxygen Consumption; D011549:Pseudomonas / Q000378:metabolism*; D014805:Vitamin B 12 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism
chemical_list: D014805:Vitamin B 12
keywords: Capacitance; Morphology; Pseudomonas denitrificans; Specific oxygen consumption rate; Vitamin B12