Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/30/2007
Publication Date: 3/1/2008
Citation: Leytem, A.B., Kwanyuen, P., Plumstead, P.W., Maguire, R., Brake, J. 2008. Evaluation of Phosphorus Characterization in Broiler Ileal Digesta, Manure, and Litter Samples: 31P-NMR vs. HPLC. Journal of Environmental Quality 37:494-500. Interpretive Summary: Evaluation of two different methods, 31-Phosphorus Nuclear Magnetic Resonance (31P-NMR) spectroscopy and High Performance Liquid Chromatography (HPLC), to quantify myo-inositol hexakisphosphate (phytate) in ileal digesta, manure, and litter from broilers was successful. The quantification in all samples was very consistent between the two methods, with a strong linear relationship between the two measurements. This suggests that both 31P-NMR and the conventional HPLC methods are very reliable methods for quantifying phosphorus compounds and phytate respectively in manure/litter samples.
Technical Abstract: Using 31-Phosphorus Nuclear Magnetic Resosonance Spectroscopy (31P-NMR) to characterize phosphorus (P) in manures and litter has become prevalent in the area of nutrient management. To date, there has been no published work evaluating P quantification in manure/litter samples with 31P-NMR compared to more traditional and accepted methods such as high performance liquid chromatography (HPLC). To evaluate the use of 31P-NMR to quantify myo-inositol hexakisphosphate (phytate) in ileal digesta, manure, and litter from broilers, we compared results obtained from both 31P-NMR and a more traditional HPLC method. The quantification of phytate in all samples was very consistent between the two methods, with linear regression ranging from 0.94 to 1.07 and r2 values of 0.84 to 0.98. We compared the concentration of total monoester P determined with 31P-NMR with the total inositol P content determined with HPLC and found a strong linear relationship between the two measurements having slopes ranging from 0.91 to 1.08 and r2 values of 0.73 to 0.95. This suggests that 31P-NMR is a very reliable method for quantifying P compounds in manure/litter samples.