High-performance liquid chromatographic (HPLC) analysis of a crossbred brown rice variety (UKMRC-9) shows high GABA content

Abstract

The neurotransmitter γ-aminobutyric acid (GABA) is a functional food ingredient of growing importance in the preparation of GABA-enriched germinated brown rice (GBR). Quantification of GABA levels during germination in a locally developed high yielding red rice variety (UKMRC-9) was carried out via high-performance liquid chromatography (HPLC) analysis using pre-column chemical derivatisation with 2-hydroxynaphthaldehyde (HN) using a UV detection system. Factors that influence rice germination such as soaking time and temperature were also studied. The results of this study showed that the UKMRC-9 rice variety soaked in water for 6 hours at 35 °C yielded the highest value for both germination percentage (95.4±1.2%) and GABA content (411 μg g-1). This suggests that long soaking times of 1-4 days can be substituted by short soaking times to produce high GABA levels in germinated brown rice.