Abstract
Pure inositol tetra-and hexaphosphate were isolated as the main components of rice phytin by Dowex 1 column chromatography. Phytase of wheat bran was purified more than 1, 500 folds. This phytase preparation showed 1) broad substrate specificity, 2) pH optimum at about 5.0, 3) no activation by magnesium ion, and 4) inhibition by fluoride ion for all the substrates tested; and was concluded as nonspecific acid phosphomonoesterase rather than phytin-specific phosphatase. The effects of metalic ions, thiol reagents, chelating agents, arsenate, alkylarsenate and hydrolysis products for this enzyme were studied. Michaelis constants and activation energy by this enzyme to various substrates were also calculated.
