Table 1_Euglena gracilis-derived β-1,3-glucan as a growth substrate for Lactococcus lactis—a snapshot of accompanying changes in transcriptomic and metabolomic profiles.xlsx

However, its potential to reprogram the metabolic profile of lactic acid bacteria has not been reported previously. In the present study, the effects of insoluble β-1,3-glucan on growth dynamics, gene expression, and the extracellular metabolite profile of Lactococcus lactis DSM20175 were investigated using transcriptomic and untargeted metabolomic approaches.

Real-time growth monitoring combined with flow cytometric cell enumeration showed that β-1,3-glucan supplementation significantly increased both growth rate and final cell density compared with a control group that did not receive any supplementation. Transcriptomic analysis showed a broad downregulation of genes associated with carbon catabolite repression, Rgg/GadR/MutR-family regulators, surface proteins, and membrane transporters, likely indicating an earlier transition from exponential to stationary phase physiology.