Phenolic profile and antioxidant activity of Jasonia glutinosa herbal tea. Influence of simulated gastrointestinal in vitro digestion

Abstract

In order to value J. glutinosa DC (rock tea), we characterised its phenolic profile and antioxidant activity. The study was performed in aqueous extracts before and after a simulated in vitro digestion to obtain data regarding phenolics bioavailability. Methanolic extracts were also analysed for comparison purposes. Phytochemical profiles were determined by high-performance liquid chromatography with mass spectrometric detection, whereas total phenolic content (TPC) and antioxidant assays were performed by conventional spectro-photometric methods. The most abundant compounds were dicaffeoylquinic acids, representing more than 90%of phenolics in tea infusions. Statistically significant differences were observed for all parameters except for TPC in methanol and aqueous extracts. Both phenolics amount and antioxidant activities were lower after the in vitro digestion of the infusions. However, although phenolics were lost during the simulated digestion, rock tea is still a good source of bioactive compounds with potential applications in the pharmaceutical or nutraceutical industries.