a b s t r a c t Evaluation of novel enzyme reactions and reactor systems is often hampered by costs related to obtaining sufficient amounts of enzymes. In this respect, it will be advantageous to assess new enzymatic processes in microbioreactors designed to resemble genuine reactor systems. In this work, we present a continu-ous membrane microbioreactor prototype for development of enzyme catalyzed degradation of pectin. Membrane reactors are becoming increasingly important for the novel 'biorefining' type of processes that either require product removal to avoid product inhibition or rest on partial hydrolysis of the substrate to obtain e.g. value-added oligosaccharides from complex biopolymers. The microbioreactor prototype was fabricated from poly(methylmethacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) and designed as a loop reactor (working volume approximately 190 L) integrated with a regenerated cellulose mem-brane for separation of low molecular weight products. The main technical considerations and challenges related to establishing the continuous membrane microbioreactor are discussed. The workability of the prototype was validated by comparing the process data at microscale to those obtained using a lab-scale membrane reactor system. The prototype presented here is easy to handle, has a low complexity – thus a relatively simple fabrication process – and can be used to study extended enzymatic reactions.