| CAT | Catalase |
| GABA | Gamma-aminobutyric acid |
| GABA-AT | GABA aminotransferase |
| GAD | Glutamate decarboxylase |
| GDH | l-glutamate dehydrogenase |
| GRAS | generally recognized as safe |
| LAB | lactic acid bacteria |
| MSG | monosodium glutamate |
| ODHC | 2-oxoglutarate dehydrogenase complex |
| PLP | pyridoxal-5′-phosphate |
| SSA | succinic semialdehyde |
| SSADH | succinate semialdehyde dehydrogenase |
| TCA | tricarboxylic acid |