Screening of phytase producers and optimization of culture conditions for submerged fermentation

• Published in: Bioprocess and biosystems engineering Vol. 37; no. 4; pp. 609 - 616
• Main Authors: Coban, Hasan B., Demirci, Ali
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2014; Springer Nature B.V
• Subjects: 6-Phytase - biosynthesis; Aspergillus - growth & development; Aspergillus ficuum; Bioengineering; Biotechnology; Chemistry; Chemistry and Materials Science; Environmental Engineering/Biotechnology; Enzymes; Fermentation; Food Science; Fungal Proteins - biosynthesis; Hydrogen-Ion Concentration; Industrial and Production Engineering; Industrial Chemistry/Chemical Engineering; Microbiology; Original Paper; Phytase; Submerged; Growth parameters; Optimization
• ISSN: 1615-7591; 1615-7605
• DOI: 10.1007/s00449-013-1028-x

Phytase (myo-inositol-hexakisphosphate phosphohydrolase) is an enzyme, which breaks down phytate to inositol and orthophosphoric acid. Phytase has been used as feed additive, and in some medical applications for years. To date, phytase production has been usually performed as a solid-state fermentation with small production volumes. Therefore, the aim of this study was to increase the phytase activity in submerged fermentations by screening several microorganism strains based on the literature to select the most productive phytase producer and optimizing growth parameters such as temperature, pH, and aeration level using response surface methodology (RSM). As a result, among the four different microorganisms evaluated, Aspergillus ficuum (NRRL 3135) was selected as the most productive strain. Optimum temperature, pH, and aeration values were determined as 33 °C, 4.5, and 0.9 vvm, respectively, for A. ficuum in 2-l batch submerged phytase productions. Under these conditions, phytase activity was measured as 2.27 U/ml. Therefore, this is a unique study showing the production of phytase with A. ficuum successfully in submerged fermentation as opposed to the traditional solid-state fermentation.