Determination of biogenic amines in licorice (Glycyrrhiza glabra) by ion-pair extraction and liquid chromatography-tandem mass spectrometry

BACKGROUND: Ion-pair extraction combined with liquid chromatography-tandem mass spectrometry method has been proposed for the determination of biogenic amines in licorice samples. RESULTS: Limit of detection and limit of quantitation for the biogenic amines were 1.4-2.7 and 4.7-9.1 ng mL(-1), respectively. Relative standard deviations based on five replicate extraction of 100 ng mL(-1) of each biogenic amine were <4.7% for intra-day and 7.4% for inter-day precision. The method described in this study has been shown to be in accordance with satisfactory accuracy and good reproducibility for the quantitative determination of biogenic amines in licorice samples. Nine biogenic amines (putrescine, cadaverine, histamine, spermine, spermidine, tyramine, tryptamine, agmatine and phenylethylamine) were detected in licorice samples and total biogenic amine concentrations were determined at 369 ng mL(-1) in fresh and 3532 ng mL(-1) in non-fresh licorice samples. Putrescine was found at the highest concentrations to be up to 704 ng mL(-1) in all the analyzed samples, followed by tyramine (675 ng mL(-1)) and tryptamine (282 ng mL(-1)). Putrescine, tyramine and spermine concentrations were dramatically increased, whereas agmatine concentration was significantly decreased, in non-fresh licorice samples compared to fresh ones. CONCLUSION: The consumption of freshly prepared licorice is recommended because of the relatively low concentration of total biogenic amines. (C) 2016 Society of Chemical Industry