OBJECTIVE: To establish the simultaneous determination method for flavonoids contents of narirutin

naringin

rhoifolin

hesperidin

neohesperidin and nobiletin in immature fruit of citrus aurantium

and to probe into the effects of different storage time on the quality of immature fruit of citrus aurantium. METHODS:（ 1） Ultra-high performance liquid chromatography（ UPLC） was used to detect the flavonoids contents of narirutin

naringin

rhoifolin

hesperidin

neohesperidin and nobiletin in immature fruit of citrus aurantium. The WATERS ACQUITY UPLC HSS T3 chromatographic column（ 2. 1 mm × 100 mm

1. 8 μm） was used. Water（ containing 0. 2% acetic acid）-acetonitrile was used as mobile phase

with gradient elution. The detection wavelength was 330 nm

the column temperature was 30 ℃

with flow rate of 0. 3 ml/min.（ 2） High-performance liquid chromatography（ HPLC） was used to detect the content of synephrine in immature fruit of citrus aurantium. The Agilent TC-C18 chromatographic column（ 4. 6 mm × 250 mm

5 μm） was used

methanol-water（ 0. 06% potassium dihydrogen phosphate in water

0. 1% sodium dodecylsulfonate

0. 1% glacial acetic acid）（ V∶ V = 1∶ 1） was used as the mobile phase

the flow rate was 1. 0 ml/min

the column temperature was 30 ℃ and the detection wavelength was 275 nm. RESULTS: UPLC can be used to detect flavonoids compounds

and HPLC can be used to detect synephrine. The method has better precision

repeatability

stability and sample recovery

and can be used for the determination of the content of the sample. There is no obvious regularity in the contents of narirutin

rhoifolin

hesperidin

nobiletin and synephrine in immature fruit of citrus aurantium. With the prolonged storage time

the naringin content increased and the neohesperidin content decreased. CONCLUSIONS: The UPLC method of simultaneous determination about the flavonoids contents of narirutin

naringin

rhoifolin

hesperidin

neohesperidin and nobiletin in immature fruit of citrus aurantium was developed. According to the samples of different origin and storage time within 7 years

there was no significant difference in the quality of citrus aurantium with flavonoids and synephrine content as evaluation indicators.