Objective Targeted terpenoids metabolome detection and analysis were carried out to provide references for further analysis of terpenoids metabolism pathway in segment membrane at different fruit development stages.

Method UPLC-MS/MS was used to detect terpenoids in segment membrane at four fruit development stages (Green, yellowish-green, greenish-yellow and yellow fruit stages), and the qualitative and quantitative analysis of metabolites, sample quality control analysis, principal component analysis (PCA), cluster analysis, OPLS-DA, KEGG functional annotation and enrichment analysis of differential metabolites were used to explore the differences of terpenoids metabolites at four fruit development stages.

Result A total of 215 metabolites were detected, including 90 monoterpenes, 51 triterpenes, 49 sesquiterpenes, 16 diterpenes, 4 triterpenoid saponins, and 5 other terpenoids. The content of limonin and nomilin was relatively high. Terpenoids accumulated relatively more at the green fruit stage, but their accumulation exhibits specificity at different fruit development stages. A total of 79 significantly different metabolites were identified, not including limonin and nomilin. The enrichment degree of monoterpenes and diterpenes biosynthesis was high and significant at four development stages.

Conclusion The content of terpenoids is relatively high at the green fruit stage, with a high degree of enrichment in the biosynthesis of monoterpenes and diterpenes.