Differential Analysis of Five Chinese Fresh Peach Metabolites Based on Non-target Metabolomics

Objective: To investigate the differences in metabolites of Chinese nectarine, peento, yellow peach, Yangshan honey peach and Xinyi honey peach by using non-target metabolomics. Methods: 250 Fresh peaches of comparable maturity were used as test materials, and the fresh peach pulp was determined by high performance liquid chromatography-quadrupole tandem time-of-flight mass spectrometry (UPLC-QTOF-MS), and the metabolites of different varieties of fresh peaches were investigated by principal component analysis and metabolite variability analysis. Results: A total of 74 metabolites were detected, mainly phenolic acids, flavanols, flavonols, anthocyanins, amino acids, glycosides, iridoid glycosides, B vitamins, etc. PCA analysis revealed that compared with the other 4 fresh peaches, Yangshan honey peach had higher contents of 7-hydroxycoumarin, pinocembrin, chlorogenic acid, neochlorogenic acid, epicatechin, procyanidin A₂, cryptochlorogenic acid, plantagoside, procyanidin B₂, and lower levels of vitamin B₂, kaempferol, rutin. Based on OPLS-DA analysis, 4 fresh peaches were screened for differential metabolites with Yangshan honey peach respectively. Nectarine had 18 species of procyanidin B₃ and other metabolites, peento had 12 species of procyanidin B₂ and other metabolites, yellow peach had 18 species of procyanidin A₂ and other metabolites, and Xinyi honey peach had 15 species of procyanidin C₁ and other metabolites, which could be used as a potential biomarker to differentiate between Yangshan honey peach and the other 4 fresh peaches. In this study, the differential metabolites of the 5 fresh peaches were mainly plant polyphenolic compounds, and chlorogenic acid and procyanidin metabolites were high in Yangshan honey peach, which were the key differential metabolites. Conclusion: The non-target metabolomics technology can effectively distinguish the five fresh peaches, which is feasible for the identification of fresh peaches, and can be used to assist the qualitative identification of fresh peaches and deep-processed fresh peaches as an important basis for the identification of true and false Yangshan honey peaches, and it is of great significance to protect the development of Yangshan honey peach speciality industry.