Optimization of Tannase Production from Raoultella ornithinolytica using Corn (Zea mays) Leaves in Solid State Fermentation

ABSTRACT Tannase has significant importance due to its various industrial applications. Tannase production using pure tannic acid as substrate is very expensive especially at industrial level. In present study, various physical parameters and medium components were optimized for maximum tannase production employing Raoultella ornithinolytica in solid state fermentation (SSF) using corn (Zea mays) leaves as substrate to reduce its production cost. The maximum tannase production was obtained with 60% initial substrate moisture contents, tap water as enzyme extraction medium with 2 mL volume, 45°C incubation temperature, pH 7, 300 µL inoculum size, 24 h incubation period in agitated condition with substrate particle size of 4mm during one factor at a time optimization. Concentrations of medium components (3.75% tannic acid, 0.75% K HPO and 1.25% yeast extract) were optimized with central composite design of response surface methodology. Tannase characterization data revealed that 5.0 pH, 30°C temperature, 60 minutes incubation and 0.45% of substrate concentration showed highest tannase activity. The results depict utilization potential of low cost substrate (corn leaves) to reduce the production cost of tannase.