Determination of free amino acids in propionibacterium fermentation broth by HPLC

A determination method of 18 amino acids with RP-HPLC was established.The detection conditions were as follows:2,4-dinitrofluorobenzene(DNFB)as pre-column derivatization reagent,TIANHE Kromasil C18(4.6mm 250mm,5 m) as the reversed-phase column,gradient elution and mobile phase A:0.05mm sodium acetate buffer solution(pH 5.3);phase B:acetonitrile:water by 1 ∶ 1(v/v),Under the above conditions,correlation coefficients of linear regression equations of amino acids could reach above 0.9991,and recovery of 18 kinds of amino acids determination was in between 95%103%.The method was quick and reliable.Moreover,it was used to detect amino acids in Propionibacterium fermentation broth.