Chromatographic Method for Determination of the Amino Acid Content in Dioscorea bulbifera L. Tubers by RP-HPLC

The present study was carried out for determination of amino acid content in tubers of Dioscorea bulbifera using reverse-phase high-performance liquid chromatography. The method involved the vapor phase hydrolysis of the sample, automated derivatisation of the amino acids with the aid of AccQ-Fluor reagent kit, separated on a high performance liquid chromatography equipped with photo diode array (HPLC-PDA) at 254 nm having column temperature of 37 ºC. The proportional molar concentration for each amino acid was calculated based on the concentration of standard amino acids and expressed as μg amino acid/mg sample. Methionine, aspartic acid and leucine were major components while as tyrosine was found minor from the plant on dry weight basis. The method is reliable, simple and economical for determining the amino acid content of Dioscorea bulbifera tubers.