Fermentation　conditions　affect　pectinase　production.　Among　these　conditions,　fermentation　period　is　one　of　the　important　parameters　to　be　optimized　for　saving　the　process　costs.　However,　information　regarding　whether　metabolic　regulation　plays　a　role　is　not　available.　Here,　a　Bacillus　licheniformis　strain　DY2　was　incubated　in　submerged　fermentation　for　pectinase　production　for　48　h.　The　pectinase　activity　was　assayed　every　4　h　from　8th　h　of　fermentation.　The　pectinase　activity　was　low　at　8　h,　middle　at　28　h,　and　peak　at　44　h.　Consistently,　metabolomics　analysis　showed　that　the　metabolic　shift　is　related　to　the　fermentation　period.　The　metabolomes　exhibited　almost　of　differential　metabolites　in　the　enriched　metabolic　pathways,　which　were　decreased　at　28　h　and　44　h　compared　to　8　h　in　a　time-dependent　manner.　Furthermore,　reduced　palmitic　acid　and　stearic　acid　in　a　time-dependent　manner　were　identified　as　crucial　biomarkers　at　48　h.　These　findings　in　our　work　reveal　that　the　reduced　fatty　acid　biosynthesis　is　required　for　pectinase　yield,　which　was　further　demonstrated　by　addition　of　inhibitors　furfural　and　triclosan　to　inhibit　pyruvate　dehydrogenase　and　fatty　acid　biosynthesis,　respectively.　Our　work　reveals　a　potential　possibility　to　elevate　pectinase　yield　through　metabolomics　modulation.　©　2020　Elsevier　Ltd