Determination of 1-deoxynojirimycin in 22 Kinds of Mulberry Leaves Using High-performance Liquid Chromatography with a Fluorescence Detector

[Objective] The contents of 1-deoxynojirimycin( DNJ) in 22 kinds of mulberry leaves were determined by derivatization with 9-fluorenylmethyl chloroformate followed by high-performance liquid chromatography equipped with a fluorescence detector( HPLC-FLD). [Method]DNJ was extracted from mulberry leaves by water bath and ultrasonic extraction,then derivatized using FMOC-Cl in K3BO3 buffer solution( p H =8. 5). The fluorescent product FMOC-DNJ was detected by HPLC-FLD. The mobile phase was acetonitrile and water( containing 0. 1% acetic acid). The elution process was optimized,which was different from the articles reported before. The derivatized DNJ in the extracts of mulberry leaves was separated by a gradient elution.[Result]The linear range of the method is 2. 02- 40. 50 mg / L and the correlation coefficient( R2) is0. 999 1. The limits of detection( LOD) and quantification( LOQ) of the method are 0. 15 and 0. 50 μg / ml,respectively. The range of recoveryis shown to be 93. 73%- 97. 91%.[Conclusion]The effect of quantifying DNJ in mulberry leaves is satisfactory by the optimized HPLC-FLD method.