TY - JOUR
T1 - Improvement of poly-γ-glutamic acid biosynthesis in a moving bed biofilm reactor by Bacillus subtilis NX-2
AU - Jiang, Yongxiang
AU - Tang, Bao
AU - Xu, Zongqi
AU - Liu, Kun
AU - Xu, Zheng
AU - Feng, Xiaohai
AU - Xu, Hong
N1 - Publisher Copyright:
© 2016 Elsevier Ltd.
PY - 2016/10/1
Y1 - 2016/10/1
N2 - The production of poly-γ-glutamic acid (γ-PGA) by Bacillus subtilis NX-2 using a moving bed biofilm reactor (MBBR) system was tested for the first time in this study. Polypropylene TL-2 was chosen as a suitable carrier, and γ-PGA concentration of 42.7 ± 0.86 g/L and productivity of 0.59 ± 0.06 g/(L h) were obtained in batch fermentation. After application of the strategy of dissolved oxygen (DO)-stat feeding, higher γ-PGA concentration and productivity were achieved than with glucose feedback feeding. Finally, the repeated fed-batch cultures implemented in the MBBR system showed high stability, and the maximal γ-PGA concentration and productivity of 74.2 g/L and 1.24 g/(L h) were achieved, respectively. In addition, the promotion of oxygen transfer by an MBBR carrier was well explained by a computational fluid dynamics (CFD) simulation. These results suggest that an MBBR system could be applied to large-scale γ-PGA production.
AB - The production of poly-γ-glutamic acid (γ-PGA) by Bacillus subtilis NX-2 using a moving bed biofilm reactor (MBBR) system was tested for the first time in this study. Polypropylene TL-2 was chosen as a suitable carrier, and γ-PGA concentration of 42.7 ± 0.86 g/L and productivity of 0.59 ± 0.06 g/(L h) were obtained in batch fermentation. After application of the strategy of dissolved oxygen (DO)-stat feeding, higher γ-PGA concentration and productivity were achieved than with glucose feedback feeding. Finally, the repeated fed-batch cultures implemented in the MBBR system showed high stability, and the maximal γ-PGA concentration and productivity of 74.2 g/L and 1.24 g/(L h) were achieved, respectively. In addition, the promotion of oxygen transfer by an MBBR carrier was well explained by a computational fluid dynamics (CFD) simulation. These results suggest that an MBBR system could be applied to large-scale γ-PGA production.
KW - Bacillus subtilis NX-2
KW - CFD simulation
KW - DO-stat
KW - Moving bed biofilm reactor
KW - Poly(γ-glutamic acid)
UR - http://www.scopus.com/inward/record.url?scp=84976338427&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2016.06.103
DO - 10.1016/j.biortech.2016.06.103
M3 - 文章
C2 - 27376835
AN - SCOPUS:84976338427
SN - 0960-8524
VL - 218
SP - 360
EP - 366
JO - Bioresource Technology
JF - Bioresource Technology
ER -
