Authors: Judit Willenbacher Michaela Zwick Teresa Mohr Ferdinand Schmid Christoph Syldatk Rudolf Hausmann
Publish Date: 2014/08/27
Volume: 98, Issue: 23, Pages: 9623-9632
Abstract
Biosurfactants increasingly gain attention due to the manifold of possible applications and production on the basis of renewable resources Owing to its various characteristics Surfactin is one of the most studied biosurfactants Since its discovery several Surfactin producers have been identified but their capacity to produce Surfactin has not been evaluated in a comparison Six different Bacillus strains were analyzed regarding their ability to produce Surfactin in model fermentations with integrated foam fractionation for in situ product enrichment and removal Three of the investigated strains are commonly used in Surfactin production ATCC 21332 DSM 3256 DSM 3258 whereas two Bacillus strains are described for the first time DSM 1090 LM43a50°C as Surfactin producers Additionally the Bacillus subtilis type strain DSM 10T was included in the evaluation Interestingly all strains except DSM 3256 featured high values for Surfactin recovered from foam in comparison to other studies ranging between 04 and 105 g The fermentation process was characterized by calculating procedural parameters like substrate yield Y X/S product yield Y P/X specific growth rate μ specific productivity q Surfactin volumetric productivity q Surfactin Surfactin and bacterial enrichment as well as Surfactin recovery The strains differ most in specific and volumetric productivity nevertheless it is evident that it is not possible to name a Bacillus strain that is the most appropriate for the production of Surfactin under these conditions In contrast it becomes apparent that the choice of a specific strain should depend on the applied fermentation conditionsThe authors would like to thank Dr Ralph Lovis for his research contribution During his work at the Institute of Process Engineering in Life Sciences at the Karlsruhe Institute of Technology KIT he isolated the Bacillus strain LM43a50°C which was later rediscovered and used in the current study
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