Phytase production by a thermophilic mould Sporotrichum thermophile in solid state fermentation and its potential applications

Phytase production by a thermophilic mould Sporotrichum thermophile Apinis was investigated in solid state fermentation (SSF) using sesame oil cake as the substrate. Scanning electron microscopy of the fermented sesame oil cake revealed a dense growth of the mould with abundant conidia. Glucose, ammonium sulphate and incubation period were identified as the most significant factors by Plackett-Burman design. The optimum values of the critical components determined by central composite design of response surface methodology for the maximum phytase production were glucose 3%, ammonium sulphate 0.5% and incubation period 120 h. An overall 2.6-fold improvement in phytase production was achieved due to optimization. Highest enzyme production (348.76 U/g DMR) was attained at a substrate bed depth of 1.5 cm in enamel coated metallic trays. The enzyme liberated inorganic phosphate from wheat flour and soymilk with concomitant dephytinization and liberation of soluble inorganic phosphate. (c) 2007 Elsevier Ltd. All rights reserved.