Determination of Spermidine and other 10 Biogenic Amines in Radix astragali (Huang qi) by HPLC-DAD with Precolumn Derivatization

Background: Radix astragali (a Tonic-Qi traditional Chinese medicine) can enhance cellular metabolism and increase the lifespan of cells. Spermidine can markedly extend the lifespan. On the basis of these considerations, we assumed whether any relationship existed between the anti-aging activity of Radix astragali and spermidine. Methods: In this research, spermidine and 10 other kinds of biogenic amines in Radix astragali samples were identified and determined using high performance liquid chromatography-diode array detector (HPLC-DAD) with precolumn derivatization. Biogenic amines were extracted with hydrochloric acid, purified by n-butyl alcohol-dichloromethane extraction, and reacted with dansyl chloride for derivatization before HPLC analysis. Results: The method had good repeatability and reproducibility for the quantitative determination of biogenic amines in Radix astragali samples. Putrescine, spermidine, and spermine were detected in 10 batches of Radix astragali samples. The total biogenic amines concentration was 48.09±2.22 mg/kg. Spermidine (22.84±2.59 mg/kg) was the highest amine in Radix astragali samples, followed by putrescine and spermine. This is the first report that Radix astragali contains biogenic amines, especially high content spermidine. Conclusion: The high content of spermidine might be the one reason for Radix astragali with Tonic- Qi and anti-aging effect.