Metabolomics Analysis Reveals Dynamic Accumulation of Sugar and Acid during Stem Development of Brassica juncea

The composition and content of sugar acid are important indicators organ development the quality horticultural products. B. juncea is an vegetable in cruciferous family, with a swollen fleshy stem as edible organ. Elucidating characteristics accumulation during expansion mustard its regulatory mechanism could enhance quality. In this study, physiological such dry matter content, sugar–acid related enzyme activities were measured eight stages tumorous stem. results showed that sucrose contents initially increased then decreased development: Sucrose exhibited positive correlation synthase phosphate synthase, while was highly positively correlated malate dehydrogenase. Further analysis dynamic patterns metabolite using metabolomics 1097 metabolites detected, including 229 organic acids derivatives, 109 lipids, other metabolites. Metabolic pathway enrichment significantly enriched acids, amino glycolysis/gluconeogenesis, starch, metabolism. Analysis tricarboxylic cycle revealed obvious differences type metabolites, most upregulated S3 S4. expression genes associated biosynthesis found based on differentially expressed at different developmental stages, gene levels verified by qPCR, which consistent accumulation. These suggest sugars, play critical role regulating stems. Results present study offer theoretical basis to improving approach determine dynamics enzymes between these levels, provides novel insights into potential mechanisms underlying