Increase　of　pectinase　activity　is　especially　important　in　fermentation　industry.　Understanding　of　the　metabolic　mechanisms　can　find　metabolic　modulation　approach　to　promote　high　yield　of　pectinase.　Higher　activity　of　pectinase　was　detected　in　DY1　than　DY2,　two　strains　of　Bacillus　licheniformis.　GC–MS-based　metabolomics　identified　differential　metabolome　of　DY2　compared　with　DY1,　characterizing　the　increased　TCA　cycle　and　biosynthesis　of　fatty　acids.　Elevated　activity　of　pyruvate　dehydrogenase　(PDH),　α-ketoglutaric　dehydrogenase　(KGDH)　and　succinate　dehydrogenase　(SDH)　showed　global　elevation　of　carbon　metabolism,　which　is　consistent　with　the　result　that　lowers　glucose　in　DY2　than　DY1.　Inhibitors　malonate,　furfural　and　triclosan,　of　PDH,　SDH　and　biosynthesis　of　fatty　acids,　promoted　pectinase　activity,　where　triclosan　increased　pectinase　activity　by　179%.　These　results　indicate　that　functional　metabolomics　is　an　effective　approach　to　understand　metabolic　mechanisms　of　fermentation　production　and　provides　clues　to　develop　new　methods　for　changing　bacterial　physiology　and　production.　©　2018,　Society　for　Industrial　Microbiology　and　Biotechnology.