Objective To investigate the effects of different types of vinegar as processing excipients on the main components and antioxidant activity of Qingpi (Citri Reticulatae Pericarpium Viride, CRPV), aiming to provide a basis for optimizing the vinegar stir-frying processing technology and establishing quality standards for vinegar used as a processing excipient in traditional Chinese medicine. Methods The influence of 20 batches of vinegar as processing excipients on the main components of CRPV was studied using HPLC combined with chemical pattern recognition. The antioxidant activity of CRPV processed with different vinegars was determined by DPPH and ABTS assays. A comprehensive score was calculated by weighting averaging of principal component scores based on their contribution rates. Orthogonal partial least squares-discrimination analysis (OPLS-DA) was employed to identify differential markers for distinguishing different vinegar-processed products. Results A total of 15 common peaks were calibrated in the HPLC of vinegar-processed CRPV, and six flavonoids, including narirutin, hesperidin, didymin, hesperetin, sinensetin, and nobiletin, were identified. Principal component analysis (PCA) indicated that CRPV processed with mature vinegar achieved the highest comprehensive score, followed by those processed with white vinegar, rice vinegar, and balsamic vinegar, respectively. Hesperetin and hesperidin can serve as differential markers to distinguish the different vinegar-processed CRPV products. In vitro antioxidant assays showed that CRPV processed with white vinegar exhibited the strongest DPPH radical scavenging ability, while raw CRPV possessed the optimal ABTS radical scavenging capacity. The antioxidant potency composite (APC) index was highest for the white vinegar-processed product ranked the highest, followed by those processed with aromatic vinegar, rice vinegar, and aged vinegar. Conclusions The type of vinegar excert selective effects on the dissolution and transformation of flavonoid components in CRPV and modulate its antioxidant activity. Mature vinegar is more conducive to the retention of flavonoid components, while white vinegar can significantly enhance its antioxidant capacity. In practical applications, the selection should be tailored according to specific therapeutic objectives.

vinegar  /  Citri Reticulatae Pericarpium Viride  /  HPLC content determination  /  chemical pattern recognition  /  antioxidant activity  /  narirutin  /  hesperidin  /  didymin  /  hesperetin  /  sinensetin  /  nobiletin