Evaluation of changes in chemical composition and antioxidant activities from vine tea at different harvest times based on LC-MS, GC-MS, and data fusion algorithms

This study systematically analyzed the chemical composition of vine tea using LC-MS and GC–MS to determine its optimal harvest time and key antioxidant compounds. By employing mass defect filtering (MDF) and a data fusion algorithm, the study examined compositional changes across different harvesting periods. The results identified 62 and 57 compounds through GC–MS and LC-MS, respectively. In vitro antioxidant assays revealed that vine tea harvested in July exhibited the strongest antioxidant activity. Correlation analysis further identified five key antioxidant compounds: myricetin, dihydromyricetin, quercetin, kaempferol, and quercitrin. This research not only clarifies the primary substances responsible for vine tea's antioxidant properties but also provides scientific guidance for optimizing harvest timing. Furthermore, the integrated analytical approach adopted in this study offers a novel strategy for exploring the chemical composition and bioactivity of vine tea and other traditional Chinese herbal medicines, paving the way for further advancements in this field. • GC-MS and LC-MS identified 62 volatile and 57 non-volatile compounds. • Machine learning algorithms and data fusion strategies screened 24 chemical components across different vine tea periods. • The vine tea harvested in late July exhibited the strongest antioxidant activity. • Myricetin, dihydromyricetin, quercetin, kaempferol and quercitrin were confirmed as vine tea's antioxidant components.