2012|13 Annual Report Fraunhofer IGB

92 BIOSURF – NEW PRODUCTION PROCESSES FOR BIOSURFACTANTS Priv.-Doz. Dr. Steffen Rupp Biosurfactants – surface-active compounds from microorganisms Surfactants are an integral part of our daily life that can be found in applications spanning from washing and cleaning agents to additives in food production as well as in oil produc- tion. Every year about 18 million metric tons of surfactants are manufactured mainly chemically and on the basis of mineral oil. A quarter of it is meanwhile being produced from oils of renewable resources, usually from coconut and palm kernel oil. Microorganisms also produce surface-active compounds, also called biosurfactants. Only a few of these biosurfactants are already produced industrially as their manufacture is compara- tively costly. In the BioSurf Project funded by the BMBF via the ”ERA-NET Industrial Biotechnology” program, the Fraunhofer IGB coordinates a consortium of seven partners who drive the development of new cost-efﬁcient processes for the microbial and enzymatic manufacture of biosurfactants. In this project both new enzymes for the biotechnological synthesis of sur- factants are developed and microorganisms are selected, par- ticularly fungi of the Pseudozyma species, and optimized us- ing molecular biological methods. The aim is to optimize the properties of the surfactants and to improve the efﬁciency of their production. Optimized fermentation for glycolipids Within the Fraunhofer IGB we focus particularly on the devel- opment of new fermentation processes for the production of mannosylerythritol lipids (MEL) and cellobiose lipids (CL) from the Pseudozyma species. Furthermore, the optimization of glycolipids following the fermentation process is also tested, with the aid of enzymes, for example. Important parameters for the fermentation process are optimized growth conditions and a high product formation rate. The aim is also to create the desired product composition by keeping contamination and the production of by-products as low as possible. Here we are trying to optimize the product range of the microor- ganisms and the fermentation conditions, also through meta- bolic engineering. A further challenge is the economical pu- riﬁcation of the compounds in the fermentation broth. Many surfactants also create foams; a fact that may impair the fer- mentation process and which thus needs to be controlled. Beneﬁts of biosurfactants In comparison to conventionally manufactured surfactants made from mineral oil biosurfactants possess only little toxic- ity, are biocompatible and biodegradable as well as often pos- sessing better surfactant characteristics. They can also show a more complex structure and possess a broader scope. Many biosurfactants have an antimicrobial effect, which makes them an interesting component for skin cleansing products. Some biosurfactants have excellent foam-forming and dirt- binding properties which render them ideal for applications in shower gels, shampoos and washing-up liquids. For the phar- maceutical industry biosurfactants are interesting due to their bioactive effect on human cells. CHEMISTRY 1 2

2012|13 Annual Report Fraunhofer IGB

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