| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
USDA-ARS, Animal Manure and By-Products Laboratory, BARC-East, 10300 Baltimore Ave., Beltsville, MD 20705
* Corresponding author (thdao{at}anri.barc.usda.gov)
Received for publication March 11, 2002. Information is needed on organic polyphosphates such as myo-inositol 1,2,3,5/4,6-hexakis dihydrogenphosphate or phytate (IP6) contribution to the sources and sinks of dissolved phosphorus (PO4–P) in the soil–manure–water system. Effects of Na+, Ca2+, Al3+, and Fe3+ and cation to IP6-P mole ratios on the enzymatic dephosphorylation of IP6 were studied to determine controlling mechanisms of dephosphorylation and persistence in manure. Phytate- and PO4–P were analyzed by high-performance liquid chromatography. Phytate dephosphorylation by Aspergillus ficuum (Reichardt) Henn. phytase EC 3.1.3.8 decreases by 50 ± 3.6 and 40 ± 4% at pH 4.5 and 6, respectively, as Ca2+ concentrations increase and cation to IP6-P mole ratios reach 6:6. Polyanionic IP6 has a high affinity for Al3+ and Fe3+ and reductions in dephosphorylation average 27 and 32% at a cation to IP6-P mole ratio of 1:6 for Al3+ and Fe3+, respectively, while reaching more than 99% at a mole ratio of 6:6. A phytase-hydrolyzable phosphorus (PHP) fraction is native to ruminant animal manure and is proportional to total solids (TS) concentration in 1 to 100 g L-1 suspensions. Added phytase, in effect, increases water-extractable P content of manure and the risk of environmental P dispersion. As the bioavailability and ecological effect of IP6-P appear to be regulated not only by pH-controlled enzyme activity but also by the associated counterions, the differential protective effects of cations influence the accuracy of manure PHP fraction estimates and increase phytate resistance to enzymatic dephosphorylation that may lead to its persistence in manure.
Abbreviations: IP6, phytate • PHP, phytase-hydrolyzable phosphorus • TS, total solids
Related articles in JEQ:
This article has been cited by other articles:
|
|
 |
|
  J. G. Warren, C. J. Penn, J. M. McGrath, and K. Sistani The Impact of Alum Addition on Organic P Transformations in Poultry Litter and Litter-Amended Soil J. Environ. Qual., March 1, 2008; 37(2): 469 - 476. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Z. He, C. W. Honeycutt, T. Zhang, P. J. Pellechia, and W. A. Caliebe Distinction of Metal Species of Phytate by Solid-State Spectroscopic Techniques Soil Sci. Soc. Am. J., May 16, 2007; 71(3): 940 - 943. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. He, T. Ohno, B. J. Cade-Menun, M. S. Erich, and C. W. Honeycutt Spectral and Chemical Characterization of Phosphates Associated with Humic Substances Soil Sci. Soc. Am. J., August 22, 2006; 70(5): 1741 - 1751. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. He, C. W. Honeycutt, T. Zhang, and P. M. Bertsch Preparation and FT-IR Characterization of Metal Phytate Compounds. J. Environ. Qual., July 1, 2006; 35(4): 1319 - 1328. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. S. Toor, B. J. Cade-Menun, and J. T. Sims Establishing a Linkage between Phosphorus Forms in Dairy Diets, Feces, and Manures J. Environ. Qual., July 5, 2005; 34(4): 1380 - 1391. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. H. Dao Ligands and Phytase Hydrolysis of Organic Phosphorus in Soils Amended with Dairy Manure Agron. J., July 1, 2004; 96(4): 1188 - 1195. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. H. Dao Organic Ligand Effects on Enzymatic Dephosphorylation of myo-Inositol Hexakis Dihydrogenphosphate in Dairy Wastewater J. Environ. Qual., January 1, 2004; 33(1): 349 - 357. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Journal of Natural Resources and Life Sciences Education |
Vadose Zone Journal | ||||
| Soil Science Society of America Journal | Journal of Plant Registrations | The Plant Genome | |||
