Chemical fingerprint and metabolic profile analysis of Citrus reticulate ‘Chachi’ decoction by HPLC-PDA-IT-MSn and HPLC-Quadrupole-Orbitrap-MS method

• Twenty-seven constituents in Citrus reticulate ‘Chachi’ decoction (CRCD) were identified or tentatively assigned.
• Forty-three compounds were detected in dosed SD rat plasma sample.
• The chemical fingerprint of CRCD by HPLC-PDA-IT/MSn was established.
• The metabolic profile of CRCD in SD rat plasma was elucidated.

A method incorporating HPLC-PDA-IT-MSn with HPLC-Quadrupole-Orbitrap-MS was developed for the investigation of chemical fingerprint of Citrus reticulate ‘Chachi’ decoction (CRCD) and metabolic profile of SD rat plasma sample after oral administration of CRCD (1.5 g herb/kg). A total of 27 chemical constituents of CRCD were identified from their MW, UV spectra, MSn data and retention behavior by comparing the results with those of the reference standards or literature. And 43 compounds were detected in dosed SD rat plasma samples, including 9 prototypes which were identified as hesperetin, isosinensetin, sinensetin, tetramethyl-O-isoscutellarein, nobiletin, tetramethyl-O-scutellarein, HMF (3,5,6,7,8,3′,4′-heptamethoxyflavone), tangeretin and 5-demethylnobiletin and 34 metabolites underwent metabolic process of demethylation, glucuronide conjugation, sulfate conjugation or mixed modes. This is the first research for the metabolic profile of CRCD in SD rats, which could lay a foundation for the further studies of CRC or its formulation.