ABSTRACT
Objective: A high performance liquid chromatography-ultraviolet-fluorescence (HPLC-UV-FLD) derivative system was established and the anti-oxidant activity of the extract of Gongcheng Tea was preliminarily evaluated by using a micro-injector imaging system combined with a fluorescent probe. Methods: Hydrogen peroxide assay and hydroxyl radical scavenging ability experiments were carried out on the anti-oxidant activity of Gongcheng Tea. The anti-oxidant components of Gongcheng Tea were screened by HPLC-UV-FLD post column derivation system and analyzed by an ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF MS). At the same time, the hydrogen peroxide scavenging activity of tea and active components were tested by a micro-injector imaging system combined with a hydrogen peroxide fluorescent probe (NBCD) in living Drosophila melanogaster. Results: The method was simple and rapid, and three main anti-oxidant compounds, epigallocatechin, epigallocatechin gallate, and epicatechin gallate were found in Gongcheng Tea. And it was found that they could significantly reduce the level of hydrogen peroxide in D. melanogaster. Conclusion: It laid a material basis for the further study of the anti-oxidant activity of Gongcheng Tea, and provided a reference for the screening of anti-oxidants in natural products.