Abstract: This study determined the content of synephrine and ethanol-extract in Citrus aurantium using near-infrared spectroscopy.The determination results were reconfirmed with HPLC analysis and hot dip assay.The near-infrared spectroscopy was combined with chemometrics to establish the quantitative model of synephrine and ethanol-extract in C.aurantium. The correlation coefficients (R²) of synephrine and ethanol-extract were 0.98052 and 0.98489,respectively.The root mean-square error of calibration (RMSEC) were 0.00915 and 0.153,respectively.The root-mean-square error of predication (RMSEP) were 0.0119 and 0.188, respectively. The validation coefficients (r) were 0.9106 and 0.9484,respectively.The developed method was convenient,fast and accurate.It was feasible to determine the content of synephrine and ethanol-extract in C.aurantium.

Key words: near-infrared spectroscopy, Citrus aurantium, determination