CHARACTERIZATION OF PHYTASES FROM CEREAL GRAINS AS AFFECTED BY SOAKING AND GERMINATION PROCESSES AND SOME METALS IONS
Abdel - Gawad,, A., Ramadan, B., B. Omar, M., E.A. Oraby, R. (2008). CHARACTERIZATION OF PHYTASES FROM CEREAL GRAINS AS AFFECTED BY SOAKING AND GERMINATION PROCESSES AND SOME METALS IONS. EKB Journal Management System, 39(4), 17-35. doi: 10.21608/ajas.2008.270069
A. Abdel - Gawad,; B. Ramadan; Mohamed B. Omar; Refat E.A. Oraby. "CHARACTERIZATION OF PHYTASES FROM CEREAL GRAINS AS AFFECTED BY SOAKING AND GERMINATION PROCESSES AND SOME METALS IONS". EKB Journal Management System, 39, 4, 2008, 17-35. doi: 10.21608/ajas.2008.270069
Abdel - Gawad,, A., Ramadan, B., B. Omar, M., E.A. Oraby, R. (2008). 'CHARACTERIZATION OF PHYTASES FROM CEREAL GRAINS AS AFFECTED BY SOAKING AND GERMINATION PROCESSES AND SOME METALS IONS', EKB Journal Management System, 39(4), pp. 17-35. doi: 10.21608/ajas.2008.270069
Abdel - Gawad,, A., Ramadan, B., B. Omar, M., E.A. Oraby, R. CHARACTERIZATION OF PHYTASES FROM CEREAL GRAINS AS AFFECTED BY SOAKING AND GERMINATION PROCESSES AND SOME METALS IONS. EKB Journal Management System, 2008; 39(4): 17-35. doi: 10.21608/ajas.2008.270069

CHARACTERIZATION OF PHYTASES FROM CEREAL GRAINS AS AFFECTED BY SOAKING AND GERMINATION PROCESSES AND SOME METALS IONS

Assiut Journal of Agricultural Sciences
Article 2, Volume 39, Issue 4, December 2008, Page 17-35  XML PDF (461.46 K)
Document Type: Original Article
DOI: 10.21608/ajas.2008.270069
View on SCiNiTO View on SCiNiTO
Authors
A. Abdel - Gawad,; B. Ramadan; Mohamed B. Omar; Refat E.A. Oraby
Dept of Food Science and Technology Faculty of Agriculture, Assiut University
Abstract
The properties of phytases of raw, soaked and germinated wheat, barley, sorghum and maize were studied. The optimal pH value was 5.0 for wheat, barley and sorghum phytases and 5.5 for maize germ phytase. The optimal temperature of wheat and barley phytases was 55oC while of sorghum and maize germ it was 50oC. Both optimal pH and temperature of phytases of different cereal grains did not affect by soaking or germination processes. Data revealed that maximal activity of phytase was found to be at 2.0 mM sodium phytate concentration from wheat, barley and sorghum and at 1.5 mM from maize germ. The calculated Michael's constant (Km) and their corresponding Vmax values of the extracted phytases from 96 h-germinated studied grains were varied. The enzyme activity was decreased with extending the incubation time more than 2 h for wheat, barley and maize germ phytase, and more than 1 h for sorghum phytase. Ca2+ ions addition caused less reduction of phytase activity of all studied cereals, whereas others metal ions had variable effect on reduction of enzyme activity. Wheat and sorghum showed high increase in their phytase activities after 120 h- germination. The same effect  was observed after 96 h-germination of barley and maize germ. At above germination times, phytase activity increased by 5.4-, 4.6-, 7.3- and 6.9-folds for wheat, barley, sorghum and maize germ, respectively compared with that before germination.
Keywords
Phytase activity; cereal grains; soaking; germination; inactivation factors
Supplementary Files
Statistics
Article View: 95
PDF Download: 81