Thermostable phytase production by Thermoascus aurantiacus in submerged fermentation.
Phytases act on phytic acid, an antinutrient factor present in animal feeds, and release inorganic phosphate. We optimized the production parameters for phytase production using Thermoascus aurantiacus (TUB F 43), a thermophilic fungal culture, by submerged fermentation. A semisynthetic medium containing glucose, starch, peptone, and minerals supplemented with 3.75% (w/v) wheat bran particles was found to be the best production medium among the various combinations tried. Further supplementation of this medium with surfactants such as Tween-20 and Tween-80 considerably enhanced the enzyme yield. A maximum phytase activity (468.22 U/mL) was obtained using this production medium containing 2% (v/v) Tween-20 after 72 h of fermentation at 45 degrees C in shake-flask cultures with a rotation of 150 rpm. Herein we present details of a few of the process parameter optimizations. The phytase enzyme was found to be thermostable, and the optimal temperature for phytase activity was found to be 55 degrees C. However, 80% of the activity still remained when the temperature was shifted to 70 degrees C.
Biotechnology Division, Regional Research Laboratory, CSIR, Trivandrum 695 019, India.
K Madhavan
KM
Nampoothiri
G Jino
GJ
Tomes
Krishnan
K
Roopesh
George
G
Szakacs
Viviana
V
Nagy
Carlos Ricardo
CR
Soccol
Ashok
A
Pandey
D010832:6-Phytase / Q000096:biosynthesis*; D003470:Culture Media; D004043:Dietary Fiber / Q000378:metabolism; D004795:Enzyme Stability; D005658:Fungi / Q000187:drug effects / Q000201:enzymology*; D006358:Hot Temperature; D010710:Phosphates / Q000378:metabolism; D013501:Surface-Active Agents / Q000494:pharmacology
D003470:Culture Media; D004043:Dietary Fiber; D010710:Phosphates; D013501:Surface-Active Agents; D010832:6-Phytase