The GBR sprouts were freeze-dried and ground to powder prior
to analysis for the GABA content. The freeze-dried powder sample
(0.500 g) was mixed with 5 mL 10% trichloroacetic acid, and the
samples extracts were shaken on an oscillator for 1 min and then
held at 40 C for 2 h to extract the GABA. The extracts were
centrifuged at 10,000 rpm for 15 min and the supernatants were
filtered through a 0.45 mm filter. The GABA content of the filtrate
was determined by high performance liquid chromatography
(HPLC).