Journal of Biotechnology & Biomaterials
Open Access

Abstract

Th e solid state culture supernatant of Rhizopus oryzae containing phytase was purifi ed using ammonium sulphate precipitation and subsequent ion-exchange and gel fi ltration chromatography. Molecular size estimated by SDS-PAGE and Gel fi ltration, was found to be ~34 kDa and ~34-36 kDa, respectively. Kinetic studies manifested a signifi cant low Km, high catalytic effi ciency (kcat/Km) and low activation energy values of 2.42 x 10-4mM, 2.38 x 106 M-1s-1 and 28.99 kJmol-1, respectively. An uncompetitive inhibition was observed in presence of tested inhibitors (Fluoride > Phosphate > Vanadate). An in vitro study in milieu of physiological conditions revealed an unusual stability of this phytase with a degradation upto 50% of phytate content. Further, the ability of this phytase to completely degrade the phytate to its lower derivative (inositol tris-phosphate) was assessed by an improved method of HPLC analysis. Phytase showed optimum temperature at 45ºC and bihump pH optima of 1.5 and 5.5. Additionally, isolated phytase showed broad substrate specifi city, strong pepsin-resistant ability and insensitivity toward heavy metal ions.

Biography

Richa Rani (M. Tech (Biotechnology), Gold Medallist) has submitted her Ph. D. Thesis in 2011 to Department of biotechnology, Indian Institute of Technology Roorkee, Roorkee. She is currently involved in designing an easily scalable lab scale fermentor meant for solid state fermentation. A part of the work has been sent for patenting in April 2010 only. She has published important publication in a reputed journal ‘Bioresource Technology’.