University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Vegetable -> peanut -> meal

Citations 2

"Amino-acid Analysis Of Feedstuff Hydrolysates By Pre-column Derivatization With Phenyl Isothiocyanate And Reversed-phase High Performance Liquid Chromatography"
Cereal Chem. 1987 Volume 64, Issue 4 Pages 226-229
R. G. Elkin and A. M. Wasynczuk

Abstract: Maize, peanut meal, two sorghum varieties and a maize - soya-bean meal-based complete mixed feed were either untreated or oxidized with performic acid before hydrolysis with HCl. Amino-acids in the hydrolysate were derivatized with phenyl isothiocyanate and the resulting phenylthiocarbamoyl derivatives were analyzed by HPLC on a column (15 cm x 3.9 mm) of Pico-Tag operated at 33°C. Elution was effected with a gradient from 90 to 0 to 90% of 0.14 M Na acetate containing 0.7 mL L-1 of triethanolamine in aqueous 60% acetonitrile and detection was at 254 nm. Amino-acids were also determined in hydrolysates by cation-exchange chromatography (J. Assoc. Off. Anal. Chem., 1985, 68, 1028) and post-column derivatization with ninhydrin. Amino-acid values by HPLC generally agreed with those by cation-exchange chromatography. Complete separation of 17 hydrolysate amino-acids plus methionine and cysteic acid was achieved in 25 min by HPLC and, thus, use of modular HPLC equipment provides a viable alternative to the use of amino-acid analyzers.
Amino Acids HPLC Spectrophotometry Heated reaction Post-column derivatization Pre-column derivatization

"Amino-acid Analysis Of Feedstuff Hydrolysates By Cation-exchange High Performance Liquid Chromatography"
J. AOAC Int. 1985 Volume 68, Issue 5 Pages 1028-1032
Elkin RG, Griffith JE

Abstract: Corn, peanut and soya-bean meals were either untreated or oxidized with performic acid before hydrolysis with 6 M HCl containing phenol and L-aminohexanoic acid. The amino-acids were determined by HPLC on a column (25 cm x 3 mm) of cation-exchange material (Na+ form; 10 µm) with post-column derivatization with ninhydrin, and by conventional cation-exchange liquid chromatography by using a Beckman Model 119CL amino-acid analyzer.. The HPLC data were more precise than those of the second method (respective mean coefficient of variation of 0.22 and 0.67%) for amino-acid retention times, but more variable (respective mean coefficient of variation of 2.39 and 0.89%) for peak areas. Although some significant differences between the methods were noted, the amino-acid values found by both methods in general agreed very well. However, for each feed sample analyzed, the HPLC method gave consistently lower phenylalanine and tyrosine values. The results suggest that modular HPLC instrumentation can be used for the accurate and precise analysis of amino-acids in feed hydrolysates. The advantages of derivatization by ninhydrin rather than phthalaldehyde or dansyl chloride are discussed.
Amino Acids HPIC Spectrophotometry Post-column derivatization