The difference in metabolite composition between De’ang sour tea and ripe Pu’er tea both made from the Yunnan Daye tea cultivar was investigated by non-targeted metabolomics based on ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS). The results showed that there was a big difference in metabolite composition between De’ang sour tea and ripe Pu-erh tea. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) could clearly distinguish the two kinds of tea according to their metabolite composition. A total of 268 significantly differential metabolites belonging to 21 classes were detected between them, accounting for all metabolites of 63.81% of the total metabolites, including 49 amino acids, 39 fatty acids, 36 nucleotides, 29 organic acids, and 18 sugars. The differential metabolites ergothiine, 3-dimethoxyphenylacetic acid, 3-hydroxymandelic acid, acetylcholine chloride, 2-hydroxy-4-methylvaleric acid, misoglitol, L-proline, 4-dioxyheptanoic acid, propanediol, proanthocyanidin B₂, N-acetylglycine may have important contributions to the formation of the taste quality of the two kinds of tea. Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis showed that there were significant differences in the metabolism levels of amino acids and nucleotides in De’ang sour tea and Pu’er tea, and that the pathways related to amino acid metabolism and nucleotide metabolism had an important impact on the taste and quality of both kinds of tea.

Delaying aging has become a hot spot of social concern and research. Our previous studies have shown that ripe Pu-erh tea can delay aging in mice by regulating the intestinal flora, but the metabolites in response to endogenous substances in mice are not clear. In this paper, the Morris water maze test was used to detect learning and memory capacity in control, D-galactose-induced aging, and ripe Pu-erh tea-treated mice. Non-targeted metabolomics was used to detect metabolites in the brain tissue and serum of mice from each group for the purpose of exploring the anti-aging effect of ripe Pu-erh tea on D-galactose-induced aging mice, screening differential metabolites among the three groups and analyzing the related metabolic pathways. The results showed that ripe Pu-erh tea improved learning capacity, and regulated 26 differential metabolites in the brain tissue of aging mice, mainly involved in the glycerophospholipid metabolism, vitamin B₆ metabolism, histidine metabolism and purine metabolism pathways, among which the glycerophospholipid metabolism and histidine metabolism pathway were the most significant. A total of 11 differential metabolites were identified in serum, mainly involved in the metabolism of vitamin B₆ and arachidonic acid, among which vitamin B₆ metab olism pathway was the most significant. After the intervention with ripe Pu-erh tea, the contents of glycerophospholipid metabolites including phosphatidylcholine [PC (20:5/20:4)], phosphatidyl ethanlamine [PE (22:2/14:0)], phosphatidylserine [PS (20:5/18:1)] and lysophosphatidylcholine [LysoPC (18:2)], the histidine metabolite carnosine, and the vitamin B₆ metabolite pyridoxal 5’-phosphate were significantly increased in aging mice. These results suggest that ripe Pu-erh tea can delay aging by regulating lipid and amino acid metabolism.