Determination of γ-aminobutyric Acid in Sea Rice by HPLC-UV Method with 2,4-Dinitrofluorobenzene Pre-column Derivatization

2, 4-dinitrofluorobenzene (FDNB) was used as the derivatization reagent in this study to establish a method for the determination of γ-Aminobutyric acid (GABA) of polished rice, corn, sea rice, germinated sea rice for 24 h, germinated sea rice for 48 h, germinated sea rice for 72 h. The effect on the retention time of GABA derivatives of FDNB volume, ammonium acetate solution-acetonitrile as mobile phase and the pH value of the sample were studied using an HPLC-UV analyzer. The precision, repeatability and stability of the method and the recovery rate of the standard were also investigated, the result was that the content of GABA in the germinated sea rice was the highest which was 34.35 μg/mg, and the content of GABA in corn, ungerminated sea rice, germinated sea rice for 48 h and germinated sea for 72 h were 3.74, 3.63, 17.03 and 9.54 μg/mg, respectively. while the GABA content in polished rice was almost zero;When the FDNB dosage was up to 0.3 mL, the reaction is guaranteed to be complete;Using 0.5% ammonium acetate aqueous solution:acetonitrile (V:V)=85:15 as the mobile phase to overcome the instability of pump pressure;After diluted 1, 5, 10, 15, 20 and 40 time by borate buffer the pH value of samples was aroud 9.0 which ensure that the retention time of GABA derivatives hardly drifts. The precision, repeatability and stability of the method was high and the relative standard deviation values were 0.08%, 0.66% and 0.60%, respectively. The sample was stable within 24 h and the recovery rate was 99.29%~101.35%. The method was simple and reliable, it could be used for quality control of high content GABA functional foods.germination (p<0.05). Sea rice is a plant resource with high GABA content, and the time of germination was shown to had a significant effect on the content of GABA. The sea rice with high content of GABA may be potentially applied in functional food. The simple and reliable method can be used for the quality control of functional food with high GABA content.