Comparison of Methodologies to Quantify Phytate Phosphorus in Diets Containing Phytase and Excreta from Broilers

Abstract

The use of a suitable methodology to quantify the phytate phosphorus (Pphy) content in both the feed and the excreta from broilers is required to enable accurate calculation of the catalytic efficiency of the phytase supplemented in the feed. This study was conducted to compare 2 analytical methodologies (colorimetry and also high-performance liquid chromatography with a refractive index detector) in order to calculate the phytase efficiency by utilizing the results from the methodology that was shown to be the most appropriate. One hundred and twenty broilers were distributed in a (4+1)×2 factorial arrangement, corresponding to 4 diets that were equally deficient in P supplemented with increasing levels of phytase (0, 750, 1,500, and 2,250 units of phytase activity – FTU – per kg of feed) plus 1 positive control diet without phytase, supplied to male and female birds. The result indicated that the colorimetric methodology with an extraction ratio of 1:20 (mass of sample in g:volume of the solvent extractor in mL) was shown to be the most adequate. There was no interaction between the phytase level and the sex of the broilers (p>0.05). Males consumed 12% more Pphy than did females (p<0.01), but the sex of the broilers did not affect (p>0.05) the excretion and retention coefficient of Pphy. The increase in the phytase level of the diet reduced (linear, p<0.01) the Pphy excretion. The greatest Pphy retention was estimated at 87.85% when the diet contained 1,950 FTU/kg (p<0.01), indicating that it is possible to reduce the inorganic P in the formulation at an amount equivalent to 87.85% of the Pphy content present in the feed, which, in this research, corresponds to a decrease in 2.86 g of P/kg of the feed.

Efficiency of microbial phytases in diets formulated with different calcium:phosphorus ratios supplied to broilers from 35 to 42 days of age

“…The phytases evaluated in the present study were added to the feed at a concentration of 1500 units of phytase activity (FTU)/kg because in a previous metabolism assay, Naves et al (2014b) concluded that when the broiler feed was supplemented with increasing levels of 6-phytase (0, 750, 1500 and 2250 FTU/kg), the greatest PP retention coefficient (88.45%) was determined when the feed contained 1500 FTU/ kg. Therefore, the following microbial phytases were added at a concentration of 1500 FTU/kg of feed: phytase A (6-phytase ® expressed by genetically modified Aspergillus oryzae with two synthetic genes derived from the gene encoding phytase ATCC 51113 in Citrobacter braakii), phytase B (6-phytase ® produced by A. oryzae that was genetically modified with the phytase gene from Peniophora lycii), phytase C (6-phytase ® produced by Schizosaccharomyces pombe ATCC 5233 that was genetically modified with the phytase gene from Escherichia coli), phytase D (a second-generation genetic improvement of the 6-phytase ® produced by E.coli), phytase E (the first generation of the genetic improvement of the 6-phytase ® produced by E.coli) and phytase F ('wild-type' 6-phytase ® produced by E. coli).…”

“…Gross energy was determined in a bomb calorimeter (model 1261, Parr Instrument Company, Moline, IL). The concentration of PP was determined by the colorimetric method with a 1:20 extraction ratio as described by Naves et al (2014b). In parallel, three homogeneous aliquots of each experimental diet were collected, ground and stored until the same chemical analyses that were conducted for the excreta were performed.…”

Data on the chemical composition, bioactive compounds, fatty acid composition, physico-chemical and functional properties of a global chickpea collection

“…The mixture was centrifuged at 6000× g and 10 °C, and the absorbance was then read at 500 nm using a Cary 60 UV–Vis spectrophotometer (Agilent Technologies Inc., Santa Clara, CA, USA). A calibration curve was prepared by different concentrations of phytic acid (Sigma-Aldrich Chemical Co., St. Louis, MO, USA) and the results were multiplied by 0.282 (molar ratio of phytate - phosphorus in a molecule of phytate) in order to express the phytate content in the sample as mg g −1 of phytic acid on dry matter [7].…”

Efficiency of microbial phytase supplementation in diets formulated with different calcium:phosphorus ratios, supplied to broilers from 22 to 33 days old

“…At this time, the contents were weighed, homogenized and pre‐dried in an oven at 55 °C for 72 h. After pre‐drying, the excreta were ground and stored at room temperature until that the analyses of dry matter (DM), total P, Ca, nitrogen (N) and gross energy were performed (AOAC, ). The concentration of phytate phosphorus (P phyt ) was determined by the colorimetric method with a 1:20 extraction ratio as described by Naves (). In parallel, three homogeneous aliquots of each experimental diet were collected, ground and stored until the same chemical analyses as the ones that were performed on the excreta were performed.…”