Evaluation of antioxidant properties of the different tissues of vine tea (Ampelopsis grossedentata) in stripped canola oil and sunflower oil.

The leaves of Ampelopsis grossedentata have a long history of use as a health tea and herbal medicine. Data on the distribution of active metabolites in, and antioxidant capacities of, different vine tea tissues remain incomplete. The aim of this work was to investigate the content of metabolites from A. grossedentata different tissues and evaluate the antioxidant capacities of the extraction of the species in vitro and in oil systems: canola oil and sunflower oil. To evaluate the degree of lipid oxidation, the peroxide value (POV) and thiobarbituric acid-reactive substance value (TBARS) were determined, and proton nuclear magnetic resonance (¹ H-NMR) was performed. The results revealed a high total flavonoid content in each of the four extractions (>580 mg/g dried weigh). Leaf extractions exhibited higher antioxidant ability, followed by fruit extract and butylated hydroxytoluene (BHT). The POVs of oils bearing extracts of A. grossedentata and BHT maintained less than 21.08 meq/kg oil against to control with 1,406.33 ± 52.63 meq/kg oil on day 32 in canola oil, and 27.87 meq/kg oil comparing to 1,892.96 ± 48.63 meq/kg oil in control on day 24 in sunflower oil. Concurring results were also obtained in TBARS and ¹ H-NMR analysis. Our results indicated that these different tissues of A. grossedentata could be a potential antioxidant resource, and this work may contribute to the comprehensive utilization of this species. PRACTICAL APPLICATION: Leaf extracts of Ampelopsis grossedentata showed effective antioxidant properties, followed by the fruit extract, which showed similar activity to that of the synthetic antioxidant of BHT. Moreover, the investigation of different tissues within the plant may contribute to the comprehensive utilization of this species.