Integrated bioproduction and extraction of 3-methylcatechol

Pseudomonas putida MC2 is a solvent-tolerant strain that accumulates 3-meth ylcatechol. In aqueous media, 10 mM of 3-methylcatechol was produced and pr oduction was limited by 3-methylcatechol toxicity to the biocatalyst. Produ ction levels increased by introduction of a second, organic phase that prov ides the substrate toluene and extracts the product from the culture medium . Octanol was shown to be an appropriate second phase with respect to toler ance of the strain for this solvent and with respect to partitioning of bot h substrate and product. Per unit of overall reactor volume (octanol and wa ter), best results were obtained with 50% (v/v) of octanol: an overall 3-me thylcatechol concentration of 25 mM was reached with 96% of the product pre sent in the octanol phase. These product concentrations are much higher tha n in aqueous media without organic solvent, indicating that biocatalysis in an organic/aqueous two-phase system is an improved set-up for high product ion levels of 3-methylcatechol. (C) 2001 Elsevier Science B.V. All rights r eserved.