Optimisation of Microbial 3-methylcatechol Production as Affected by Culture Conditions

Pseudomonas putida MC2 can be used to produce catechols. The accumulation, specific and volumetric production rates of 3-methylcatechol from toluene have been studied. Production rates were shown to depend on growth medium, pH and toluene concentration. Minimal glucose medium and rich LB medium were the best growth media for 3-methylcatechol production. A lower pH often resulted in slower growth and a higher specific production rate, but a lower volumetric production rate. Specific production rates also increased at higher initial toluene concentrations. The best process conditions in terms of substrate conversion and specific production rate were found in minimal glucose medium at an initial aqueous toluene concentration of 1.0 λmM and an initial pH of 6. At pH 7 and 2.0 λmM toluene, more product was accumulated at a lower specific rate, but at a higher volumetric production rate.     

Spectroscopic and surface-analytical characterization of self-assembled layers on Au

Future devices for electronic, photonic or other “intelligent” application involving (bio-) organic materials require nano-fabrication, -manipulation, -patterning and -functionalization techniques. Supramolecular assemblies, aggregates, small molecules and ions have to be controlled with regard to their structure, order and dynamic behaviour down to the molecular or even atomic level.

This contribution summarizes some of our activities aiming at a better understanding of the physical and chemical properties of functionalized and patterned surfaces. We focus on structure/order-property/function relations in such complex systems as interfaces and thin film architectures. Optical techniques (surface plasmon-spectroscopy) as well as surface analytical techniques (cyclic voltammetry and contact angle investigations) are introduced and demonstrated as powerful tools for the characterization of these interfaces and thin films.

Examples will be given covering self-assembly monolayers and molecular recognition—as well as complexation-reactions.