Title:	Orthophosphate, phytate, and total phosohorus determination in cerals by flow injection analysis.
Authors:	VIEIRA, E. C. NOGUEIRA, A. R. de A.
Affiliation:	EDIVAN CARVALHO VIEIRA, UFSCAR; ANA RITA DE ARAUJO NOGUEIRA, CPPSE.
Date Issued:	2004
Citation:	Journal of Agricultural and Food Chemistry, v.52, p.1800-1803, 2004.
Description:	A flow injection spectrophotometric procedure with enzymatic hydrolysis was developed for determination of orthophosphate, phytate and total phosphorus in cereal samples. Phosphorus species were extracted from cereals with 0.05 mol L-1 potassium hydrogen phthalate buffer solution at pH 5.7. Orthophosphate was directly determined in the extracts by molybdenum blue spectrophotometric method. The phytate was hydrolyzed by the enzyme phytase coupled to a solid phase packed into an enzymatic reactor, and the resulting hydrolyzed orthophosphate was also determined by spectrophotometry at 650 nm. After optimization for phosphorus species extraction and enzymatic hydrolysis, a linear calibration graph was obtained up to 196 × 10-6 mol L-1 orthophosphate (P conc) -2.67 + 0.52x, r ) 0.9998). Measurements are characterized by relative standard deviation of 1.6% for a standard of 72 × 10-6 mol L-1 orthophosphate and no baseline drift was observed during 4 h operation periods. It provides 72 measurements per hour, with 2.4 × 10-6 mol L-1 and 7.9 × 10-6 mol L-1 as detection and quantification limits, respectively.
Keywords:	Enzymatic hysrolysis Immobilization Phytase Phytic Acid Spectophometry
DOI:	https://doi.org/10.1021/jf034467f
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CPPSE)