GC-IMS was employed to analyze volatile components in Forsythia suspensa at different harvesting stages and in various parts.

This study investigated the volatile oil extraction yield of Forsythia suspensa (F. suspensa) at different fruit developmental stages. For the first time, gas chromatography-ion mobility spectrometry (GC-IMS) coupled with chemometrics was employed to construct Gallery Plot characteristic fingerprints of volatile organic compounds (VOCs), revealing the impact of fruit developmental stages (young fruit stage, expansion stage, and maturation stage) and organ parts (pericarp vs. seed) on VOC profiles. A total of 120 VOCs were identified, with 83 compounds defined, including: aldehydes (28.9 %), ketones (18.1 %), esters (9.6 %), and terpenoids (19.3 %). Key findings included:(1) Regarding oil yield across developmental stages, the expansion stage exhibited the highest volatile oil content, while the young fruit stage showed the lowest;(2) In organ-specificity, seeds contained higher terpenoid levels (γ-Terpinene, α-Phellandrene, etc.), whereas pericarps were dominated by aldehydes and ketones (Benzaldehyde, Furfural, Methyl 5-hepten-2-one, etc.). Besides, mature fruits (laoqiao) pericarps had elevated esters (Butyl acetate, Ethyl Acetate, etc.) compared to immature fruits (qingqiao);(3) Developmental dynamics analysis indicated relatively minor differences in VOC composition in different stages. However, certain components exhibited linear changes with increasing maturity, demonstrating positive regulation of specific compound accumulation during fruit development. This research confirms distinct compositional profiles between F. suspensa pericarps and seeds warranting separate investigation, while fruit development stages influence characteristic VOC regulation. The established GC-IMS-chemometrics integrated approach provides a novel methodology for the quality assessment of traditional Chinese medicinal materials.