In a context of environmental biorefinery, i.e. using various organic resources from wastes or agricultural residues, driving the fermentation end products of anaerobic mixed cultures using the few number of environmental parameters that could be changed (pH, temperature, OLR…) is rather a difficult issue. In this study, an electrochemical control of the redox potential was proposed as an alternative solution. The use of bioelectrochemical systems (BES) to control the redox potential in dark fermentation of glucose showed a two-fold increase of hydrogen production compared to conventional fermentation. When the same system was applied to glycerol fermentation, no significant difference was observed for 1,3-PDO production. Nonetheless, the addition of electro-active bacteria in BESs increased the 1,3-PDO production by 33% compared to conventional fermentation with performances close to the theoretical maximal value. The metabolic pattern in electro-fermentation after substrate depletion was significantly different from the conventional fermentation control, with, in all cases, a substantial decrease of unwanted lactate pathway.