# Analysis of Fingerprint Profiles of Flavonoid Compounds in Rock Tea of Different Ages

## TL;DR

This study uses advanced chemical analysis to classify aged rock tea and shows its flavonoids can reduce oxidative damage and improve cognitive function in mice.

## Contribution

A UPLC–MS method was developed to classify aged rock tea and evaluate its flavonoid compounds' antioxidant and neuroprotective effects.

## Key findings

- Aged rock tea contains over 30 identifiable chemical components, enabling classification into three categories.
- Flavonoids from aged tea reduced oxidative stress and improved cognitive function in Alzheimer’s disease mice.
- The method supports quality evaluation and classification of traditional Chinese medicinal materials like aged tea.

## Abstract

This study established a chromatographic fingerprint analysis method for aged rock tea using ultra‐high performance liquid chromatography–mass spectrometry (UPLC–MS) technology to profile its chemical components. The chromatographic separation showed excellent performance, with more than 30 chemical components of common peaks identified. Comparative analysis of fingerprint profiles from different vintage‐aged teas revealed significant differences in similarity, allowing classification into three distinct categories based on similarity indices. This method facilitates the classification of aged teas and quality evaluation of traditional Chinese medicinal materials. Component analysis of aged tea demonstrated that tea extracts are rich in flavonoid compounds, both in content and diversity, serving as a primary dietary source of total flavonoids. In subsequent animal experiments, functional flavonoids derived from aged tea extracts exhibited positive regulatory effects against multiple free radicals, including ·OH, H2O2, DPPH−, and ABTS, in vitro. In vivo studies showed that these flavonoids reduced malondialdehyde (MDA) levels in the cerebral cortex of Alzheimer’s disease (AD) mice, enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), mitigated oxidative damage, and improved cognitive dysfunction in AD mice. This research provides crucial references for future studies on traditional Chinese medicines aimed at ameliorating cognitive dysfunction.