TY - JOUR
T1 - Optimization of Bacillus subtilis natto growth parameters in glycerol-based medium for vitamin K (Menaquinone-7) production in biofilm reactors
AU - Mahdinia, Ehsan
AU - Demirci, Ali
AU - Berenjian, Aydin
N1 - Publisher Copyright:
© 2017, Springer-Verlag GmbH Germany.
PY - 2018/2/1
Y1 - 2018/2/1
N2 - Menaquinone-7 (MK-7) is the key form of vitamin K used as a dietary supplement and its production revolves around Bacillus subtilis natto. Current fermentation strategies, which suggest static fermentations without aeration and agitation, can be problematic for large scale MK-7 production due to biofilm formation. The use of biofilm reactors, therefore, is proposed in the present study, which could utilize both agitation and aeration without interrupting MK-7 secretion. In this study, biofilm reactors were constructed using the selected plastic composite support (PCS) and B. subtilis natto strain for MK-7 production. Using response surface methodology (RSM), optimum growth parameters including temperature, pH, and agitation were determined in a glycerol-based medium. Results were presented in a statistical model (R2 = 0.90), leading to optimum growth conditions of temperature (35 °C), agitation (200 rpm) and pH (6.58). Model-predicted MK-7 concentration was validated and MK-7 concentration of 12.09 mg/L was produced in the biofilm reactor. The obtained concentration was 58% higher as compared to the suspended-cell culture (7.67 mg/L). The results of this study will provide a critical step towards improved industrial scale production of MK-7.
AB - Menaquinone-7 (MK-7) is the key form of vitamin K used as a dietary supplement and its production revolves around Bacillus subtilis natto. Current fermentation strategies, which suggest static fermentations without aeration and agitation, can be problematic for large scale MK-7 production due to biofilm formation. The use of biofilm reactors, therefore, is proposed in the present study, which could utilize both agitation and aeration without interrupting MK-7 secretion. In this study, biofilm reactors were constructed using the selected plastic composite support (PCS) and B. subtilis natto strain for MK-7 production. Using response surface methodology (RSM), optimum growth parameters including temperature, pH, and agitation were determined in a glycerol-based medium. Results were presented in a statistical model (R2 = 0.90), leading to optimum growth conditions of temperature (35 °C), agitation (200 rpm) and pH (6.58). Model-predicted MK-7 concentration was validated and MK-7 concentration of 12.09 mg/L was produced in the biofilm reactor. The obtained concentration was 58% higher as compared to the suspended-cell culture (7.67 mg/L). The results of this study will provide a critical step towards improved industrial scale production of MK-7.
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U2 - 10.1007/s00449-017-1857-0
DO - 10.1007/s00449-017-1857-0
M3 - Article
C2 - 29119323
AN - SCOPUS:85033410873
SN - 1615-7591
VL - 41
SP - 195
EP - 204
JO - Bioprocess and biosystems engineering
JF - Bioprocess and biosystems engineering
IS - 2
ER -