2.4. Metabolite quantification
The concentration of glucose and acetic acid were determinedby HPLC analysis on a Hitachi LaChrom Elite HPLC system equippedwith a Rezex ROA Organic Acid Column and refractive index detec-tor (RID). Culture samples were centrifuged at 10,000 rpm for15 min, and supernatant aliquots were injected in the column. TheHPLC method was run at a constant flow rate of 0.5 mL/min with5 mM H2SO4as the mobile phase, at 65◦C for 20 min.