Multiplatform Metabolomic Analysis Reveals Metabolic Reprogramming of Burkholderia cepacia During Polyhydroxyalkanoate Production from Oleic Acid

Polyhydroxyalkanoates (PHA) have emerged as biodegradable alternatives to conventional polymers. However, their high production cost remains the main limitation to large-scale commercialization. Metabolic engineering strategies have been implemented to optimize PHA quality and enhance process productivity, yet a comprehensive understanding of the intracellular metabolic regulation is still needed. In this study, an untargeted metabolomic analysis using GC–MS and LC–MS platforms was performed to characterize the endometabolome of Burkholderia cepacia during batch fermentation with oleic acid as the carbon source. A total of 24 significant metabolites were identified by GC–MS and 223 by LC–MS, mainly organic acids and lipids. These metabolites were associated with key pathways such as β-oxidation, the tricarboxylic acid cycle, and the pentose phosphate pathway. The results revealed a clear metabolic reprogramming driven by acetyl-CoA flux redistribution, reflecting a regulatory mechanism responsive to nutrient availability. This dynamic reorganization of the metabolic network supports the transition from growth to PHA accumulation. The integrative metabolomic approach applied here provides insights valuable for guiding future Design–Build–Test–Learn (DBTL) strategies in the rational optimization of PHA-producing bioprocesses.