seed culture was prepared in a 100 mL flask with 10 mL MRS broth incubated at 30 and 150 rpm for 24 h. A 4% volume of seed culture was used as its inoculum for the flask culture. In order to investigate the GABA production by L.brevis OPY-1, the flask cultures were carried out in a 250 mL flask with 50 mL of MRS broth with 1% (w/v) of monosodium glutamate (MSG) at 30 and 150 rpm for 24 h.