Determination of γ-glutamyl-S-ethenyl-cysteine in narbon vetch (Vicia narbonensis L.) seeds by high performance liquid chromatography

A new method for fast and easy determination of γ-glutamyl-S-ethenyl-cysteine (GEC) in narbon vetch (Vicia narbonensis L.) seeds was developed as a tool for the selection of low GEC varieties. Samples (n = 20) were analyzed by reverse-phase HPLC, using isocratic elution and monitoring at 215 nm. Calibration curve showed very good linearity of the response between 2.5 and 20 μg GEC. The limits of detection and quantification were 0.013 and 0.049 mg/mL, respectively. The repeatability (average coefficient of variation (CV) = 0.023) and reproducibility (average CV = 0.016) of the method were within the recommendations for the validation of HPLC methods. The method yielded similar results in comparison with a previously established method.