Abstract
The phytases (EC 3.1.3.26) and acid phosphatases (EC 3.1.3.2) of rice bran were purified. Four acid phosphatases were purified from rice bran: F1 and F2 had phytase activity, but F3 and F4 did not. The optimum pH of F1 and F2 for phytic acid were 4.4 and 4.6, respectively, and those of F1, F2, F3, and F4 for p-nitrophenyl phosphate were 5.1, 5.2, 5.4, and 6.0, respectively. Their molecular weights were estimated to be about 59-70K by SDS polyacrylamide gel electrophoresis, velocity density gradient centrifugation, and gel filtration on Ultrogel. The isoelectric points of F1, F2, F3, and F4 were 5.1, 5.1, 5.6, and 5.9, respectively. F1, F2, F3, and F4 had a violet color and F2 showed an absorption maximum peak at 560 nm. They had broad substrate specificities.
