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Foam-free production of Surfactin via anaerobic fermentation of Bacillus subtilis DSM 10(T).

Willenbacher J, Rau JT, Rogalla J, Syldatk C, Hausmann R - AMB Express (2015)

Bottom Line: The fermentations were analyzed regarding specific (qSurfactin, vol. qSurfactin) and overall product yields (YP/X, YP/S) as well as substrate utilization (YX/S).Additionally, values for specific production rate qSurfactin (0.005 g/(g∙h)) and product yield per consumed substrate (YP/S = 0.033 g/g) surpass results of comparable foam-free processes.The current study introduces an alternative to produce a biosurfactant that overcomes the challenges of severe foaming and need for additional constructions.

View Article: PubMed Central - PubMed

Affiliation: Institute of Process Engineering in Life Sciences, Section II: Technical Biology, Karlsruhe Institute of Technology (KIT), Engler-Bunte-Ring 1, 76131, Karlsruhe, Germany.

ABSTRACT
Surfactin is one of the most popular biosurfactants due to its numerous potential applications. The usually aerobic production via fermentation of Bacillus subtilis is accompanied by vigorous foaming which leads to complex constructions and great expense. Therefore it is reasonable to search for alternative foam-free production processes. The current study introduces a novel approach to produce Surfactin in a foam-free process applying a strictly anaerobic bioreactor cultivation. The process was performed several times with different glucose concentrations in mineral salt medium. The fermentations were analyzed regarding specific (qSurfactin, vol. qSurfactin) and overall product yields (YP/X, YP/S) as well as substrate utilization (YX/S). Fermentations in which 2.5 g/L glucose were employed proofed to be the most effective, reaching product yields of YP/X = 0.278 g/g. Most interesting, the product yields exceeded classical aerobic fermentations, in which foam fractionation was applied. Additionally, values for specific production rate qSurfactin (0.005 g/(g∙h)) and product yield per consumed substrate (YP/S = 0.033 g/g) surpass results of comparable foam-free processes. The current study introduces an alternative to produce a biosurfactant that overcomes the challenges of severe foaming and need for additional constructions.

No MeSH data available.


Inoculation and fermentation ofBacillus subtilisDSM 10Tin 2.5 L benchtop bioreactor. A. Direct inoculation of the benchtop fermenter using a serum bottle with preculture. Nitrogen was introduced into the serum bottle via a small filter creating excess pressure inside the bottle. A second tube was used to channel the preculture directly into the inoculum device. B. Foam-free cultivation of Bacillus subtilis DSM 10T applying an anaerobic fermentation process.
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Fig1: Inoculation and fermentation ofBacillus subtilisDSM 10Tin 2.5 L benchtop bioreactor. A. Direct inoculation of the benchtop fermenter using a serum bottle with preculture. Nitrogen was introduced into the serum bottle via a small filter creating excess pressure inside the bottle. A second tube was used to channel the preculture directly into the inoculum device. B. Foam-free cultivation of Bacillus subtilis DSM 10T applying an anaerobic fermentation process.

Mentions: The aim of the current study is to combine the relatively new research field of anaerobic biosurfactant production with a foam-free bioprocess strategy (Figure 1 B). Therefore the anaerobic growth behavior of Bacillus subtilis DSM 10T was investigated in a 2.5 L benchtop bioreactor without any gas flow through the liquid phase. Four different glucose concentrations were tested and evaluated regarding their influence on Surfactin production. The processes were analyzed focusing on maximal Surfactin concentrations (cSurfactin), growth rates (μmax), product and substrate yields (YP/X, YX/S, YP/S), specific production rates (qSurfactin) and specific volumetric production rates (vol. qSurfactin).Figure 1


Foam-free production of Surfactin via anaerobic fermentation of Bacillus subtilis DSM 10(T).

Willenbacher J, Rau JT, Rogalla J, Syldatk C, Hausmann R - AMB Express (2015)

Inoculation and fermentation ofBacillus subtilisDSM 10Tin 2.5 L benchtop bioreactor. A. Direct inoculation of the benchtop fermenter using a serum bottle with preculture. Nitrogen was introduced into the serum bottle via a small filter creating excess pressure inside the bottle. A second tube was used to channel the preculture directly into the inoculum device. B. Foam-free cultivation of Bacillus subtilis DSM 10T applying an anaerobic fermentation process.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385232&req=5

Fig1: Inoculation and fermentation ofBacillus subtilisDSM 10Tin 2.5 L benchtop bioreactor. A. Direct inoculation of the benchtop fermenter using a serum bottle with preculture. Nitrogen was introduced into the serum bottle via a small filter creating excess pressure inside the bottle. A second tube was used to channel the preculture directly into the inoculum device. B. Foam-free cultivation of Bacillus subtilis DSM 10T applying an anaerobic fermentation process.
Mentions: The aim of the current study is to combine the relatively new research field of anaerobic biosurfactant production with a foam-free bioprocess strategy (Figure 1 B). Therefore the anaerobic growth behavior of Bacillus subtilis DSM 10T was investigated in a 2.5 L benchtop bioreactor without any gas flow through the liquid phase. Four different glucose concentrations were tested and evaluated regarding their influence on Surfactin production. The processes were analyzed focusing on maximal Surfactin concentrations (cSurfactin), growth rates (μmax), product and substrate yields (YP/X, YX/S, YP/S), specific production rates (qSurfactin) and specific volumetric production rates (vol. qSurfactin).Figure 1

Bottom Line: The fermentations were analyzed regarding specific (qSurfactin, vol. qSurfactin) and overall product yields (YP/X, YP/S) as well as substrate utilization (YX/S).Additionally, values for specific production rate qSurfactin (0.005 g/(g∙h)) and product yield per consumed substrate (YP/S = 0.033 g/g) surpass results of comparable foam-free processes.The current study introduces an alternative to produce a biosurfactant that overcomes the challenges of severe foaming and need for additional constructions.

View Article: PubMed Central - PubMed

Affiliation: Institute of Process Engineering in Life Sciences, Section II: Technical Biology, Karlsruhe Institute of Technology (KIT), Engler-Bunte-Ring 1, 76131, Karlsruhe, Germany.

ABSTRACT
Surfactin is one of the most popular biosurfactants due to its numerous potential applications. The usually aerobic production via fermentation of Bacillus subtilis is accompanied by vigorous foaming which leads to complex constructions and great expense. Therefore it is reasonable to search for alternative foam-free production processes. The current study introduces a novel approach to produce Surfactin in a foam-free process applying a strictly anaerobic bioreactor cultivation. The process was performed several times with different glucose concentrations in mineral salt medium. The fermentations were analyzed regarding specific (qSurfactin, vol. qSurfactin) and overall product yields (YP/X, YP/S) as well as substrate utilization (YX/S). Fermentations in which 2.5 g/L glucose were employed proofed to be the most effective, reaching product yields of YP/X = 0.278 g/g. Most interesting, the product yields exceeded classical aerobic fermentations, in which foam fractionation was applied. Additionally, values for specific production rate qSurfactin (0.005 g/(g∙h)) and product yield per consumed substrate (YP/S = 0.033 g/g) surpass results of comparable foam-free processes. The current study introduces an alternative to produce a biosurfactant that overcomes the challenges of severe foaming and need for additional constructions.

No MeSH data available.