Revista Colombiana de Biotecnología
versão impressa ISSN 0123-3475
COSTA, Marcia et al. Phytase production by Aspergillus ficuum in submerged and solid state fermentation using agroindustrial waste as support. Rev. colomb. biotecnol [online]. 2009, vol.11, n.1, pp. 73-83. ISSN 0123-3475.
Phytase production by submerged fermentation (SmF) and solid state fermentation (SSF) using Aspergillus ficuum DSM 932 in agro-waste-based culture media is described here. Phytase enzyme activity was used for the indirect measurement of enzyme production. Fermentation was carried out in SmF, pH 5.3 at 25 °C with two fermenters having different volumes; the largest one had different levels of aeration and agitation. Petri dishes were used for SSF at 25 °C. A cereal-based medium obtained the best net activity (0.25 FTU mL-1) for SmF on the sixth day at 300 rpm at 0.5 vvm. Canola cake was the best substrate for SSF, having maximum net phytase activity on the third day: 6.79 FTU mL-1 extract, equivalent to 33.96 FTU g-1 solid substrate or 56.43 FTU g-1 dry substrate. A phytase extract was concentrated from an SmF-based medium in cereals by applying membrane technologies. A phytase extract produced in SSF with canola cakes was purified 6.33 times using three consecutive diafiltrations of the 100 kDa retentate. A. ficuum DSM 932 phytase was = 100 kDa in size.
Palavras-chave : phytase; feed enzyme; Aspergillus ficuum; canola cake; solid substrate fermentation.