Consumption of processed fish product increase year by year, especially fish flour. However, processing fish flour produce untreated wastewater that contains rich element of carbon, nitrogen, and mineral. Those rich elements can be used as alternative bacterial nutrient media. This research aims to devise a combine formulation between fish flour liquid waste and Luria Bertani media. The combine medium was used to grow recombinant Eschericia coli DH5α harboring gene encoding xylanolytic enzyme of pTP510 with ratio of combine medium 1:2, 1:2, and 1:4 compared to Luria Bertani media itself. The result showed that the optimum combine formulation was 1:2 and indicated its activity of 0.7260 Unit/mL and 0.6213 Unit/mL after 9 hours and 12 hours incubation time, respectively.